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Patients with tuberculous meningitis commonly present with stiff neck, headache, fever, and vomiting; these symptoms are also frequently observed with bacterial meningitis
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tuberculous meningitis accounted for about 1 percent of tuberculosis (TB) cases and 4 percent of extrapulmonary TB disease [1]. CLINICAL MANIFESTATIONS Signs and symptoms Typical presentation — <span>Patients with tuberculous meningitis commonly present with stiff neck, headache, fever, and vomiting; these symptoms are also frequently observed with bacterial meningitis. Features that may help distinguish tuberculous meningitis from bacterial meningitis include: ●Subacute presentation; in one study including 160 patients with tuberculous meningitis, th




Features that may help distinguish tuberculous meningitis from bacterial meningitis include:

● Subacute presentation; in one study including 160 patients with tuberculous meningitis, the time between the onset of symptoms and clinical presentation was less than one week in 7 percent of cases, 1 to 3 weeks in 57 percent, and more than 3 weeks in 36 percent. In contrast, bacterial meningitis typically presents within one week of symptoms; potential exceptions include meningitis due to listeriosis or brucellosis. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".)

● Presence of neurologic symptoms; in the above study including 160 patients with tuberculous meningitis, altered consciousness, personality changes, and coma were observed in 59, 28, and 21 percent of cases, respectively [2]. Such symptoms are not typical of bacterial meningitis. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".)

● Presence of cranial nerve palsies (most frequently involving cranial nerve II and VI) are common; other cranial nerves are infrequently involved. In one study including 158 patients with tuberculous meningitis, cranial nerve palsies were observed in almost one-third of cases. Cranial nerve palsies are uncommon with bacterial meningitis, exceptions include meningitis due to listeriosis or meningitis associated with intracranial abscess [3].

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pical presentation — Patients with tuberculous meningitis commonly present with stiff neck, headache, fever, and vomiting; these symptoms are also frequently observed with bacterial meningitis. <span>Features that may help distinguish tuberculous meningitis from bacterial meningitis include: ●Subacute presentation; in one study including 160 patients with tuberculous meningitis, the time between the onset of symptoms and clinical presentation was less than one week in 7 percent of cases, 1 to 3 weeks in 57 percent, and more than 3 weeks in 36 percent. In contrast, bacterial meningitis typically presents within one week of symptoms; potential exceptions include meningitis due to listeriosis or brucellosis. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".) ●Presence of neurologic symptoms; in the above study including 160 patients with tuberculous meningitis, altered consciousness, personality changes, and coma were observed in 59, 28, and 21 percent of cases, respectively [2]. Such symptoms are not typical of bacterial meningitis. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".) ●Presence of cranial nerve palsies (most frequently involving cranial nerve II and VI) are common; other cranial nerves are infrequently involved. In one study including 158 patients with tuberculous meningitis, cranial nerve palsies were observed in almost one-third of cases. Cranial nerve palsies are uncommon with bacterial meningitis, exceptions include meningitis due to listeriosis or meningitis associated with intracranial abscess [3]. Patients with tuberculous meningitis typically progress through three discernible phases [4-7]: ●The early prodromal phase, lasting one to three weeks, is characterized by the insidious




Patients with tuberculous meningitis typically progress through three discernible phases [4-7]:

● The early prodromal phase, lasting one to three weeks, is characterized by the insidious onset of malaise, lassitude, headache, low-grade fever, and personality change.

● The meningitic phase follows with more pronounced neurologic features, such as meningismus, protracted headache, vomiting, lethargy, confusion, and varying degrees of cranial nerve and long-tract signs.

● The paralytic phase supervenes as the pace of illness accelerates rapidly; confusion gives way to stupor and coma, seizures, and often hemiparesis. For the majority of untreated patients, death ensues within five to eight weeks of the onset of illness.

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almost one-third of cases. Cranial nerve palsies are uncommon with bacterial meningitis, exceptions include meningitis due to listeriosis or meningitis associated with intracranial abscess [3]. <span>Patients with tuberculous meningitis typically progress through three discernible phases [4-7]: ●The early prodromal phase, lasting one to three weeks, is characterized by the insidious onset of malaise, lassitude, headache, low-grade fever, and personality change. ●The meningitic phase follows with more pronounced neurologic features, such as meningismus, protracted headache, vomiting, lethargy, confusion, and varying degrees of cranial nerve and long-tract signs. ●The paralytic phase supervenes as the pace of illness accelerates rapidly; confusion gives way to stupor and coma, seizures, and often hemiparesis. For the majority of untreated patients, death ensues within five to eight weeks of the onset of illness. Clinical presentation with central nervous system (CNS) manifestations in the absence of prior history of pulmonary symptoms is common; in one series including 61 patients with tubercul




Clinical presentation with central nervous system (CNS) manifestations in the absence of prior history of pulmonary symptoms is common; in one series including 61 patients with tuberculous meningitis, history of tuberculosis (TB) disease was elicited in only 10 percent of cases [8].
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erates rapidly; confusion gives way to stupor and coma, seizures, and often hemiparesis. For the majority of untreated patients, death ensues within five to eight weeks of the onset of illness. <span>Clinical presentation with central nervous system (CNS) manifestations in the absence of prior history of pulmonary symptoms is common; in one series including 61 patients with tuberculous meningitis, history of tuberculosis (TB) disease was elicited in only 10 percent of cases [8]. In children, headache is less common than in adults; irritability, restlessness, anorexia, and protracted vomiting are prominent symptoms. Seizures are more common in children and tend




Patients may present with atypical features that mimic other neurologic conditions. These include an acute, rapidly progressive meningitic syndrome suggesting pyogenic meningitis, or with slowly progressive dementia over months characterized by personality change, social withdrawal, loss of libido, and memory deficits. Less commonly, patients may present with an encephalitic course manifested by stupor, coma, and convulsions without overt signs of meningitis [11].
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le 1). ●Stage III – Advanced illness with delirium, stupor, coma, seizures, multiple cranial nerve palsies, and/or dense hemiplegia (Glasgow coma score ≤10) (table 1). Atypical manifestations — <span>Patients may present with atypical features that mimic other neurologic conditions. These include an acute, rapidly progressive meningitic syndrome suggesting pyogenic meningitis, or with slowly progressive dementia over months characterized by personality change, social withdrawal, loss of libido, and memory deficits. Less commonly, patients may present with an encephalitic course manifested by stupor, coma, and convulsions without overt signs of meningitis [11]. Uncommonly, tuberculous meningitis may present with concomitant tuberculoma or radiculomyelopathy. (See "Central nervous system tuberculosis: An overview", section on 'Tuberculoma' and




Hydrocephalus occurs in up to 80 percent of patients with tuberculous meningitis, and is often accompanied by signs of raised intracranial pressure. Hydrocephalus should be suspected when patient has features of elevated intracranial pressure, deteriorating vision, and/or deteriorating consciousness. In such cases, neuroimaging should be performed urgently [12]
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s with tuberculous meningitis may present with symptoms characteristic of complications, as discussed in the following section. Complications — Complications of tuberculous meningitis include: ●<span>Hydrocephalus occurs in up to 80 percent of patients with tuberculous meningitis, and is often accompanied by signs of raised intracranial pressure. Hydrocephalus should be suspected when patient has features of elevated intracranial pressure, deteriorating vision, and/or deteriorating consciousness. In such cases, neuroimaging should be performed urgently [12]. Head computed tomography may demonstrate hydrocephalus, but magnetic resonance imaging is a more sensitive modality for detection of findings associated with tuberculous meningitis [13




Hyponatremia is a potentially serious complication of tuberculous meningitis. Hyponatremia may develop at any point of time during course of tuberculous meningitis. In one study including 76 cases, hyponatremia was observed in approximately 45 percent of cases [14]. The onset and progression can be insidious with nonspecific symptoms (nausea, confusion, delirium, seizure) that may be mistakenly attributable to other pathologic features of the infection or its treatment.
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ngitis [13]. (See "Normal pressure hydrocephalus" and "Evaluation and management of elevated intracranial pressure in adults" and "Hydrocephalus in children: Clinical features and diagnosis".) ●<span>Hyponatremia is a potentially serious complication of tuberculous meningitis. Hyponatremia may develop at any point of time during course of tuberculous meningitis. In one study including 76 cases, hyponatremia was observed in approximately 45 percent of cases [14]. The onset and progression can be insidious with nonspecific symptoms (nausea, confusion, delirium, seizure) that may be mistakenly attributable to other pathologic features of the infection or its treatment. (See "Manifestations of hyponatremia and hypernatremia in adults" and "Diagnostic evaluation of adults with hyponatremia".) Assessment of volume status is important to differentiate pat




Assessment of volume status is important to differentiate patients with the syndrome of inappropriate anti-diuretic hormone secretion (SIADH) from patients with central salt wasting; in general, patients with SIADH are euvolemic, while patients with central salt wasting are hypovolemic.
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table to other pathologic features of the infection or its treatment. (See "Manifestations of hyponatremia and hypernatremia in adults" and "Diagnostic evaluation of adults with hyponatremia".) <span>Assessment of volume status is important to differentiate patients with the syndrome of inappropriate anti-diuretic hormone secretion (SIADH) from patients with central salt wasting; in general, patients with SIADH are euvolemic, while patients with central salt wasting are hypovolemic. (See "Diagnostic evaluation of adults with hyponatremia".) ●Vision loss – Vision loss, a severely disabling complication of tuberculous meningitis, occurs in approximately one-quarter o




Vision loss – Vision loss, a severely disabling complication of tuberculous meningitis, occurs in approximately one-quarter of patients [15,16]. Mechanisms of vision loss include optochiasmatic arachnoiditis (encasement of optic nerves and optic chiasma by thick tuberculous exudates), compression of the optic chiasma by the dilated third ventricle from above, elevated intracranial pressure, endarteritis of vessels supplying the optic nerves and optic chiasma, and direct M. tuberculosis invasion of the optic nerves. Many survivors of tuberculous meningitis have permanent blindness.
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s with central salt wasting; in general, patients with SIADH are euvolemic, while patients with central salt wasting are hypovolemic. (See "Diagnostic evaluation of adults with hyponatremia".) ●<span>Vision loss – Vision loss, a severely disabling complication of tuberculous meningitis, occurs in approximately one-quarter of patients [15,16]. Mechanisms of vision loss include optochiasmatic arachnoiditis (encasement of optic nerves and optic chiasma by thick tuberculous exudates), compression of the optic chiasma by the dilated third ventricle from above, elevated intracranial pressure, endarteritis of vessels supplying the optic nerves and optic chiasma, and direct M. tuberculosis invasion of the optic nerves. Many survivors of tuberculous meningitis have permanent blindness. (See "Tuberculosis and the eye".) Management of complications is discussed separately. (See "Central nervous system tuberculosis: Treatment and prognosis", section on 'Management of com




Among patients with HIV infection, the presentation of tuberculous meningitis is the same as in patients without HIV infection; however, concurrent TB outside the CNS and lung occurs more commonly. In addition, initiation of antiretroviral therapy in patients with HIV infection and no prior CNS symptoms may precipitate onset of new symptoms, reflecting progression of underlying TB infection as a manifestation of immune reconstitution inflammatory syndrome.
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anagement of complications is discussed separately. (See "Central nervous system tuberculosis: Treatment and prognosis", section on 'Management of complications'.) Patients with HIV infection — <span>Among patients with HIV infection, the presentation of tuberculous meningitis is the same as in patients without HIV infection; however, concurrent TB outside the CNS and lung occurs more commonly. In addition, initiation of antiretroviral therapy in patients with HIV infection and no prior CNS symptoms may precipitate onset of new symptoms, reflecting progression of underlying TB infection as a manifestation of immune reconstitution inflammatory syndrome. (See "Immune reconstitution inflammatory syndrome".) Routine test findings — Routine blood counts and chemistries are relatively nonspecific; mild anemia is common. Hyponatremia may be




Routine blood counts and chemistries are relatively nonspecific; mild anemia is common. Hyponatremia may be observed in the context of inappropriate antidiuretic hormone or cerebral salt wasting [14,17]. Central diabetes insipidus resulting in hypernatremia has also been described [18]
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reflecting progression of underlying TB infection as a manifestation of immune reconstitution inflammatory syndrome. (See "Immune reconstitution inflammatory syndrome".) Routine test findings — <span>Routine blood counts and chemistries are relatively nonspecific; mild anemia is common. Hyponatremia may be observed in the context of inappropriate antidiuretic hormone or cerebral salt wasting [14,17]. Central diabetes insipidus resulting in hypernatremia has also been described [18]. Chest radiograph abnormalities may be seen in up to half of patients with CNS TB, ranging from focal lesions to a miliary pattern [9,18]. (See "Diagnosis of pulmonary tuberculosis in a




CT of the chest is an important diagnostic modality to evaluate for concomitant pulmonary tuberculosis (image 1). In one study including 81 patients with tuberculous meningitis, chest CT thorax abnormalities were observed in two-thirds of patients; centrilobular nodules were the most common lung parenchyma abnormality, and asymptomatic miliary lung lesions were observed in 10 percent of tuberculous meningitis cases [19]
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g' and "Clinical manifestations and complications of pulmonary tuberculosis" and "Clinical manifestations, diagnosis, and treatment of miliary tuberculosis", section on 'Radiographic imaging'.) <span>CT of the chest is an important diagnostic modality to evaluate for concomitant pulmonary tuberculosis (image 1). In one study including 81 patients with tuberculous meningitis, chest CT thorax abnormalities were observed in two-thirds of patients; centrilobular nodules were the most common lung parenchyma abnormality, and asymptomatic miliary lung lesions were observed in 10 percent of tuberculous meningitis cases [19]. The tuberculin skin test (TST) or an interferon-gamma release assay (IGRA) is frequently positive [4,5]; however, a negative result does not exclude TB. In one report including 118 Eur




The diagnosis may be definitively established in the setting of cerebrospinal fluid (CSF) with positive smear for acid-fast bacilli (AFB), CSF culture positive for M. tuberculosis, or CSF with positive nucleic acid amplification test (NAAT) [21]. However, definitive diagnosis can be challenging, given suboptimal sensitivity and specificity of diagnostic tests [20,22]
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ic health risk for transmission should be admitted and isolated with airborne precautions. (See "Tuberculosis transmission and control in health care settings", section on 'Clinical triaging'.) <span>The diagnosis may be definitively established in the setting of cerebrospinal fluid (CSF) with positive smear for acid-fast bacilli (AFB), CSF culture positive for M. tuberculosis, or CSF with positive nucleic acid amplification test (NAAT) [21]. However, definitive diagnosis can be challenging, given suboptimal sensitivity and specificity of diagnostic tests [20,22]. A presumptive diagnosis of tuberculous meningitis may be made in the setting of relevant clinical and epidemiologic factors and typical CSF findings (lymphocytic pleocytosis, elevated




A presumptive diagnosis of tuberculous meningitis may be made in the setting of relevant clinical and epidemiologic factors and typical CSF findings (lymphocytic pleocytosis, elevated protein concentration, and low glucose concentration).
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is, or CSF with positive nucleic acid amplification test (NAAT) [21]. However, definitive diagnosis can be challenging, given suboptimal sensitivity and specificity of diagnostic tests [20,22]. <span>A presumptive diagnosis of tuberculous meningitis may be made in the setting of relevant clinical and epidemiologic factors and typical CSF findings (lymphocytic pleocytosis, elevated protein concentration, and low glucose concentration). Diagnostic tools for patients with suspected tuberculous meningitis include CSF examination and radiographic imaging [23]: ●CSF examination – At the time of lumbar puncture (LP), the op




CSF examination – At the time of lumbar puncture (LP), the opening pressure should be measured. CSF should be sent for total cell count with white blood cell differential, protein concentration, and glucose concentration (with serum level for comparison), NAAT, and AFB smear and culture; in patients with HIV infection, CSF testing should also include cryptococcal antigen. Additional fluid should be saved in case additional studies are warranted
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osis, elevated protein concentration, and low glucose concentration). Diagnostic tools for patients with suspected tuberculous meningitis include CSF examination and radiographic imaging [23]: ●<span>CSF examination – At the time of lumbar puncture (LP), the opening pressure should be measured. CSF should be sent for total cell count with white blood cell differential, protein concentration, and glucose concentration (with serum level for comparison), NAAT, and AFB smear and culture; in patients with HIV infection, CSF testing should also include cryptococcal antigen. Additional fluid should be saved in case additional studies are warranted. The diagnostic yield may be increased by submitting multiple CSF specimens (at least three) from repeated LPs and greater volumes (at least 5 mL); however, empiric antituberculous ther




The diagnostic yield may be increased by submitting multiple CSF specimens (at least three) from repeated LPs and greater volumes (at least 5 mL); however, empiric antituberculous therapy should not be delayed while obtaining serial CSF specimens [24]. The sensitivity of AFB smear and culture is maintained for a few days after starting treatment, and the sensitivity of CSF NAAT is maintained for up to one month after starting treatment [17,25]
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NAAT, and AFB smear and culture; in patients with HIV infection, CSF testing should also include cryptococcal antigen. Additional fluid should be saved in case additional studies are warranted. <span>The diagnostic yield may be increased by submitting multiple CSF specimens (at least three) from repeated LPs and greater volumes (at least 5 mL); however, empiric antituberculous therapy should not be delayed while obtaining serial CSF specimens [24]. The sensitivity of AFB smear and culture is maintained for a few days after starting treatment, and the sensitivity of CSF NAAT is maintained for up to one month after starting treatment [17,25]. (See 'Spinal fluid examination' below.) ●Radiographic imaging – Radiographic tools for evaluation of patients with suspected CNS TB include computed tomography (CT) and magnetic resona




For patients with mild-to-moderate hydrocephalus in the absence of signs of elevated ICP, LP may be pursued. For patients with contraindications to immediate LP in the setting of characteristic clinical, epidemiologic, and radiographic features of CNS TB, empiric therapy should be initiated promptly (and not be deferred pending LP).
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tant in the setting of papilledema or other signs that may be indicative of elevated intracranial pressure (ICP; such as altered mental status, new-onset seizure, or focal neurologic deficits). <span>For patients with mild-to-moderate hydrocephalus in the absence of signs of elevated ICP, LP may be pursued. For patients with contraindications to immediate LP in the setting of characteristic clinical, epidemiologic, and radiographic features of CNS TB, empiric therapy should be initiated promptly (and not be deferred pending LP). Patients with suspected TB should undergo chest radiography; in the setting of relevant signs or symptoms, diagnostic evaluation for pulmonary TB should be pursued. In addition, for pat




Patients with suspected or proven tuberculous meningitis should always be tested for HIV infection.
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agnosis of pulmonary tuberculosis in adults", section on 'Radiographic imaging' and "Tuberculous lymphadenitis" and "Clinical manifestations, diagnosis, and treatment of miliary tuberculosis".) <span>Patients with suspected or proven tuberculous meningitis should always be tested for HIV infection. (See "Screening and diagnostic testing for HIV infection".) Bedside evaluation — Among patients with suspected CNS TB, a careful neurologic examination should be undertaken, including a




Among patients with suspected CNS TB, a careful neurologic examination should be undertaken, including assessment of mental status, cranial nerves, sensory and motor examination, cerebellar function, and reflexes.
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erculosis".) Patients with suspected or proven tuberculous meningitis should always be tested for HIV infection. (See "Screening and diagnostic testing for HIV infection".) Bedside evaluation — <span>Among patients with suspected CNS TB, a careful neurologic examination should be undertaken, including assessment of mental status, cranial nerves, sensory and motor examination, cerebellar function, and reflexes. (See "The detailed neurologic examination in adults".) In addition, patients should be evaluated for other systemic manifestations of TB. Signs of active TB outside the CNS are of diagn




In addition, patients should be evaluated for other systemic manifestations of TB. Signs of active TB outside the CNS are of diagnostic importance if present. Patients should be assessed for fever, weight loss, jaundice, lymphadenopathy, hepatomegaly, splenomegaly, bone and joint lesions, and dermatologic findings. In patients with miliary TB, careful funduscopic examination often demonstrates choroidal tubercles; these are multiple ill-defined raised yellow-white nodules of varying size near the optic disk (picture 1).
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ld be undertaken, including assessment of mental status, cranial nerves, sensory and motor examination, cerebellar function, and reflexes. (See "The detailed neurologic examination in adults".) <span>In addition, patients should be evaluated for other systemic manifestations of TB. Signs of active TB outside the CNS are of diagnostic importance if present. Patients should be assessed for fever, weight loss, jaundice, lymphadenopathy, hepatomegaly, splenomegaly, bone and joint lesions, and dermatologic findings. In patients with miliary TB, careful funduscopic examination often demonstrates choroidal tubercles; these are multiple ill-defined raised yellow-white nodules of varying size near the optic disk (picture 1). (See "Tuberculosis and the eye".) Spinal fluid examination Routine studies — The opening pressure is usually moderately elevated (180 to 300 mm H2O) [18]. Typical CSF findings in tuberc




Routine studies — The opening pressure is usually moderately elevated (180 to 300 mm H2O) [18]. Typical CSF findings in tuberculous meningitis include lymphocytic pleocytosis, elevated protein concentration, and low glucose concentration (table 2).

● The CSF white blood cell count is typically between 100 and 500 cells/microL, with lymphocyte predominance. Early in the course of illness, a lower cell count and/or neutrophilic predominance may be observed. In addition, neutrophilic predominance may be observed in the setting of spinal block and/or paradoxical worsening.

● The CSF protein concentration is typically 100 to 500 mg/dL. However, in patients with subarachnoid block, the CSF protein concentration may be as high as 2 g/dL [17,18]

● The CSF glucose concentration is <45 mg/dL in most cases.

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rates choroidal tubercles; these are multiple ill-defined raised yellow-white nodules of varying size near the optic disk (picture 1). (See "Tuberculosis and the eye".) Spinal fluid examination <span>Routine studies — The opening pressure is usually moderately elevated (180 to 300 mm H2O) [18]. Typical CSF findings in tuberculous meningitis include lymphocytic pleocytosis, elevated protein concentration, and low glucose concentration (table 2). ●The CSF white blood cell count is typically between 100 and 500 cells/microL, with lymphocyte predominance. Early in the course of illness, a lower cell count and/or neutrophilic predominance may be observed. In addition, neutrophilic predominance may be observed in the setting of spinal block and/or paradoxical worsening. ●The CSF protein concentration is typically 100 to 500 mg/dL. However, in patients with subarachnoid block, the CSF protein concentration may be as high as 2 g/dL [17,18] ●The CSF glucose concentration is <45 mg/dL in most cases. Acid-fast bacilli smear and culture — The sensitivity of acid-fast staining for diagnosis of tuberculous meningitis is 30 to 60 percent [24,26]. The diagnostic yield is increased with v




The sensitivity of acid-fast staining for diagnosis of tuberculous meningitis is 30 to 60 percent [24,26]. The diagnostic yield is increased with volume of CSF (up to 10 to 15 mL) and number of CSF specimens (up to four) [5,24]. AFB smears and cultures may be positive even days after treatment has been initiated
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ients with subarachnoid block, the CSF protein concentration may be as high as 2 g/dL [17,18] ●The CSF glucose concentration is <45 mg/dL in most cases. Acid-fast bacilli smear and culture — <span>The sensitivity of acid-fast staining for diagnosis of tuberculous meningitis is 30 to 60 percent [24,26]. The diagnostic yield is increased with volume of CSF (up to 10 to 15 mL) and number of CSF specimens (up to four) [5,24]. AFB smears and cultures may be positive even days after treatment has been initiated. Organisms can be demonstrated most readily in a smear of the clot or sediment. If no clot forms, addition of 2 mL of 95% alcohol induces a heavy protein precipitate that carries bacill




Organisms can be demonstrated most readily in a smear of the clot or sediment. If no clot forms, addition of 2 mL of 95% alcohol induces a heavy protein precipitate that carries bacilli to the bottom of the tube upon centrifugation
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yield is increased with volume of CSF (up to 10 to 15 mL) and number of CSF specimens (up to four) [5,24]. AFB smears and cultures may be positive even days after treatment has been initiated. <span>Organisms can be demonstrated most readily in a smear of the clot or sediment. If no clot forms, addition of 2 mL of 95% alcohol induces a heavy protein precipitate that carries bacilli to the bottom of the tube upon centrifugation. The centrifuged deposit should be applied to a glass slide (20 mcL in an area not exceeding one centimeter in diameter) and stained by the standard Kinyoun or Ziehl-Neelsen method. Bet




The sensitivity of CSF AFB culture for diagnosis of tuberculous meningitis is often <50 percent, although some studies report positive culture rates of up to 85 percent [5,24].
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had been administered before a positive smear was obtained [5]. In another study including 132 adults with suspected tuberculous meningitis, AFB smear was positive in 58 percent of cases [24]. <span>The sensitivity of CSF AFB culture for diagnosis of tuberculous meningitis is often <50 percent, although some studies report positive culture rates of up to 85 percent [5,24]. Issues related to mycobacterial culture techniques are discussed further separately. (See "Diagnosis of pulmonary tuberculosis in adults", section on 'Mycobacterial culture'.) Nucleic a




In one meta-analysis including 63 studies comprising more than 1300 patients with tuberculous meningitis (confirmed by culture), the specificity and sensitivity of NAATs were 99 percent (95% CI 98-99) and 82 percent (95% CI 75-87 percent), respectively [27].
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tuberculosis in adults", section on 'Mycobacterial culture'.) Nucleic acid amplification tests — NAATs on CSF are an important diagnostic tool due to rapid turnaround time and high specificity. <span>In one meta-analysis including 63 studies comprising more than 1300 patients with tuberculous meningitis (confirmed by culture), the specificity and sensitivity of NAATs were 99 percent (95% CI 98-99) and 82 percent (95% CI 75-87 percent), respectively [27]. NAATs may be used in combination with (but not as a substitute for) AFB smear and culture. NAAT on CSF has not been approved by the US Food and Drug Administration in the United States;




A negative Xpert MTB/RIF test result should not be used to exclude tuberculous meningitis, given variable sensitivity [22]. Mycobacterial DNA may remain detectable in CSF for up to a month after initiation of treatment [25].
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AFB smear and culture. NAAT on CSF has not been approved by the US Food and Drug Administration in the United States; however, some laboratories offer laboratory-developed and validated NAATs. <span>A negative Xpert MTB/RIF test result should not be used to exclude tuberculous meningitis, given variable sensitivity [22]. Mycobacterial DNA may remain detectable in CSF for up to a month after initiation of treatment [25]. In high prevalence settings, patients with suspected tuberculous meningitis should have CSF sent for NAAT if feasible; this tool is particularly useful in the setting of negative AFB sm




In low-prevalence settings, the Xpert MTB/RIF assay may be used as diagnostic tool if the assay has been validated by the laboratory for this indication [40]. In one systematic review and meta-analysis including 18 studies, the sensitivity and specificity for this assay in CSF (compared with culture) were 81 and 98 percent, respectively [34]. In addition, the positive predictive value of NAATs is limited in low-prevalence settings [35]
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Xpert MTB/RIF for diagnosis of tuberculous meningitis in adults with or without HIV infection [38], and some have cautioned against use of Xpert Ultra to ‘rule out’ tuberculous meningitis [39]. <span>In low-prevalence settings, the Xpert MTB/RIF assay may be used as diagnostic tool if the assay has been validated by the laboratory for this indication [40]. In one systematic review and meta-analysis including 18 studies, the sensitivity and specificity for this assay in CSF (compared with culture) were 81 and 98 percent, respectively [34]. In addition, the positive predictive value of NAATs is limited in low-prevalence settings [35]. Quantitative NAAT results may be a useful prognostic tool; a high bacterial load correlates with cycle threshold (Ct) <16, medium load with Ct 16 to 22, low load with Ct 22 to 28, a




Quantitative NAAT results may be a useful prognostic tool; a high bacterial load correlates with cycle threshold (Ct) <16, medium load with Ct 16 to 22, low load with Ct 22 to 28, and very low load with Ct >28. A high CSF M. tuberculosis bacterial load prior to treatment (measured using the Xpert MTB/RIF assay) has been associated with higher disease severity and higher likelihood of new neurologic events after initiation of therapy [41].
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cificity for this assay in CSF (compared with culture) were 81 and 98 percent, respectively [34]. In addition, the positive predictive value of NAATs is limited in low-prevalence settings [35]. <span>Quantitative NAAT results may be a useful prognostic tool; a high bacterial load correlates with cycle threshold (Ct) <16, medium load with Ct 16 to 22, low load with Ct 22 to 28, and very low load with Ct >28. A high CSF M. tuberculosis bacterial load prior to treatment (measured using the Xpert MTB/RIF assay) has been associated with higher disease severity and higher likelihood of new neurologic events after initiation of therapy [41]. Issues related to NAATs for diagnosis of pulmonary TB are discussed further separately. (See "Diagnosis of pulmonary tuberculosis in adults", section on 'NAA testing'.) Adenosine deamin




Measurement of the CSF adenosine deaminase (ADA) level may be a useful adjunctive test for diagnosis of tuberculous meningitis [23,42]. However, elevated CSF ADA level may also be observed in the setting of bacterial infections and neurobrucellosis [42,43], and there is no clear threshold to distinguish tuberculous meningitis from meningitis caused by other infectious agents.
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]. Issues related to NAATs for diagnosis of pulmonary TB are discussed further separately. (See "Diagnosis of pulmonary tuberculosis in adults", section on 'NAA testing'.) Adenosine deaminase — <span>Measurement of the CSF adenosine deaminase (ADA) level may be a useful adjunctive test for diagnosis of tuberculous meningitis [23,42]. However, elevated CSF ADA level may also be observed in the setting of bacterial infections and neurobrucellosis [42,43], and there is no clear threshold to distinguish tuberculous meningitis from meningitis caused by other infectious agents. One meta-analysis included 10 studies and more than 350 with tuberculous meningitis (most of which defined an elevated ADA as 9 or 10 U/L) estimated the sensitivity and specificity of A




One meta-analysis included 10 studies and more than 350 with tuberculous meningitis (most of which defined an elevated ADA as 9 or 10 U/L) estimated the sensitivity and specificity of ADA for diagnosis of tuberculous meningitis to be 79 and 91 percent, respectively [44]. Another meta-analysis including 13 studies and more than 1000 patients with tuberculous meningitis noted the sensitivity and specificity of ADA for diagnosis of tuberculous meningitis depended on the definition of an elevated ADA level [45]. For ADA threshold of 4 U/L, the sensitivity and specificity were >93 and <80 percent, respectively; for ADA threshold of 8 U/L, the sensitivity and specificity were <59 and >96 percent, respectively.
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ved in the setting of bacterial infections and neurobrucellosis [42,43], and there is no clear threshold to distinguish tuberculous meningitis from meningitis caused by other infectious agents. <span>One meta-analysis included 10 studies and more than 350 with tuberculous meningitis (most of which defined an elevated ADA as 9 or 10 U/L) estimated the sensitivity and specificity of ADA for diagnosis of tuberculous meningitis to be 79 and 91 percent, respectively [44]. Another meta-analysis including 13 studies and more than 1000 patients with tuberculous meningitis noted the sensitivity and specificity of ADA for diagnosis of tuberculous meningitis depended on the definition of an elevated ADA level [45]. For ADA threshold of 4 U/L, the sensitivity and specificity were >93 and <80 percent, respectively; for ADA threshold of 8 U/L, the sensitivity and specificity were <59 and >96 percent, respectively. Radiographic imaging — Radiographic modalities for evaluation of patients with suspected CNS TB include brain CT or brain MRI [46,47]. Brain MRI is superior to CT in defining lesions of




In patients with tuberculous meningitis, classical neuroimaging findings include hydrocephalus, basilar exudates, periventricular infarcts, and cerebral parenchymal tuberculomas (image 2 and image 3 and image 4 and image 5 and image 6) [18,22]. Presence of basilar meningeal enhancement along with presence of hydrocephalus is strongly suggestive of tuberculous meningitis (image 6) [50-53].
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es for evaluation of patients with suspected CNS TB include brain CT or brain MRI [46,47]. Brain MRI is superior to CT in defining lesions of the basal ganglia, midbrain, and brainstem [48,49]. <span>In patients with tuberculous meningitis, classical neuroimaging findings include hydrocephalus, basilar exudates, periventricular infarcts, and cerebral parenchymal tuberculomas (image 2 and image 3 and image 4 and image 5 and image 6) [18,22]. Presence of basilar meningeal enhancement along with presence of hydrocephalus is strongly suggestive of tuberculous meningitis (image 6) [50-53]. In the setting of stage I disease, the CT scan is normal in approximately 30 percent of cases. In the setting of stage III disease, CT findings may include hydrocephalus as well as basi




In the setting of stage I disease, the CT scan is normal in approximately 30 percent of cases. In the setting of stage III disease, CT findings may include hydrocephalus as well as basilar enhancement. Marked basilar enhancement has been correlated with presence of vasculitis and risk for basal ganglia infarction
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and image 4 and image 5 and image 6) [18,22]. Presence of basilar meningeal enhancement along with presence of hydrocephalus is strongly suggestive of tuberculous meningitis (image 6) [50-53]. <span>In the setting of stage I disease, the CT scan is normal in approximately 30 percent of cases. In the setting of stage III disease, CT findings may include hydrocephalus as well as basilar enhancement. Marked basilar enhancement has been correlated with presence of vasculitis and risk for basal ganglia infarction. In two large community-based series, hydrocephalus was observed in approximately 75 percent of cases, basilar meningeal enhancement in 38 percent, cerebral infarcts in 15 to 30 percent




In two large community-based series, hydrocephalus was observed in approximately 75 percent of cases, basilar meningeal enhancement in 38 percent, cerebral infarcts in 15 to 30 percent, and tuberculomas in 5 to 10 percent [50,51]
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disease, CT findings may include hydrocephalus as well as basilar enhancement. Marked basilar enhancement has been correlated with presence of vasculitis and risk for basal ganglia infarction. <span>In two large community-based series, hydrocephalus was observed in approximately 75 percent of cases, basilar meningeal enhancement in 38 percent, cerebral infarcts in 15 to 30 percent, and tuberculomas in 5 to 10 percent [50,51]. In a case series from Hong Kong including 31 patients with tuberculous meningitis, hydrocephalus was observed on presentation in 9 cases; among 22 patients without initial hydrocephalu




Optochiasmatic arachnoiditis, an important cause of vision loss, is characterized radiographically by presence of tuberculous exudates in the region of interpeduncular, suprasellar, perimesencephalic, and Sylvian cisterns [54].
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is, hydrocephalus was observed on presentation in 9 cases; among 22 patients without initial hydrocephalus, hydrocephalus developed after the start of antituberculous therapy in 1 patient [52]. <span>Optochiasmatic arachnoiditis, an important cause of vision loss, is characterized radiographically by presence of tuberculous exudates in the region of interpeduncular, suprasellar, perimesencephalic, and Sylvian cisterns [54]. Periventricular brain infarcts are seen in up to half of patients and are common in advanced disease. Most infarcts are observed in the basal ganglia. In many patients, infarcts are asy




Periventricular brain infarcts are seen in up to half of patients and are common in advanced disease. Most infarcts are observed in the basal ganglia. In many patients, infarcts are asymptomatic and not associated with focal neurologic deficits [55,56].
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mportant cause of vision loss, is characterized radiographically by presence of tuberculous exudates in the region of interpeduncular, suprasellar, perimesencephalic, and Sylvian cisterns [54]. <span>Periventricular brain infarcts are seen in up to half of patients and are common in advanced disease. Most infarcts are observed in the basal ganglia. In many patients, infarcts are asymptomatic and not associated with focal neurologic deficits [55,56]. Radiographic manifestations of tuberculoma and spinal arachnoiditis, with may occur in patients with tuberculous meningitis, are described below. (See "Central nervous system tuberculos




Fungal meningitis (cryptococcosis, histoplasmosis, blastomycosis, coccidioidomycosis) – As with tuberculous meningitis, fungal meningitis often presents subacutely and may be associated with cranial neuropathies. Immunosuppression (due to HIV infection or other causes) is an important risk factor. In patients with cryptococcal meningitis, the CSF profile classically demonstrates elevated opening pressure, low white blood cell count with a mononuclear predominance, slightly elevated protein concentration, and low glucose concentration. Definitive diagnosis is made by CSF culture; a positive cryptococcal antigen in the CSF or serum strongly suggests the presence of infection.
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(subacute or chronic meningitis syndrome with cerebrospinal fluid [CSF] characterized by a lymphocytic pleocytosis, lowered glucose concentration, and elevated protein concentration) includes: ●<span>Fungal meningitis (cryptococcosis, histoplasmosis, blastomycosis, coccidioidomycosis) – As with tuberculous meningitis, fungal meningitis often presents subacutely and may be associated with cranial neuropathies. Immunosuppression (due to HIV infection or other causes) is an important risk factor. In patients with cryptococcal meningitis, the CSF profile classically demonstrates elevated opening pressure, low white blood cell count with a mononuclear predominance, slightly elevated protein concentration, and low glucose concentration. Definitive diagnosis is made by CSF culture; a positive cryptococcal antigen in the CSF or serum strongly suggests the presence of infection. (See "Epidemiology, clinical manifestations, and diagnosis of Cryptococcus neoformans meningoencephalitis in patients with HIV" and "Clinical manifestations and diagnosis of Cryptococcu




Neurobrucellosis – Brucellosis typically presents with insidious onset of fever, malaise, night sweats, and arthralgias. It may be complicated by neurobrucellosis; manifestations include meningitis, encephalitis, brain abscess, myelitis, radiculitis, and/or neuritis (with involvement of cranial or peripheral nerves). CSF findings include a pleocytosis (10 to 200 white blood cells, predominantly mononuclear cells), mild to moderately elevated protein levels, hypoglycorrhachia, and elevated adenosine deaminase. The diagnosis may be established via antibody or agglutination testing of spinal fluid; uncommonly, the organism may be recovered in CSF culture.
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s of Cryptococcus neoformans meningoencephalitis in patients with HIV" and "Clinical manifestations and diagnosis of Cryptococcus neoformans meningoencephalitis in HIV-seronegative patients".) ●<span>Neurobrucellosis – Brucellosis typically presents with insidious onset of fever, malaise, night sweats, and arthralgias. It may be complicated by neurobrucellosis; manifestations include meningitis, encephalitis, brain abscess, myelitis, radiculitis, and/or neuritis (with involvement of cranial or peripheral nerves). CSF findings include a pleocytosis (10 to 200 white blood cells, predominantly mononuclear cells), mild to moderately elevated protein levels, hypoglycorrhachia, and elevated adenosine deaminase. The diagnosis may be established via antibody or agglutination testing of spinal fluid; uncommonly, the organism may be recovered in CSF culture. (See "Brucellosis: Epidemiology, microbiology, clinical manifestations, and diagnosis".) ●Neurosyphilis – Meningitis and meningovascular disease are manifestations of early neurosyphili




Neurosyphilis – Meningitis and meningovascular disease are manifestations of early neurosyphilis. Clinical manifestations of syphilitic meningitis include headache, confusion, nausea, vomiting, and stiff neck; in addition, cranial neuropathies may occur. Visual acuity may be impaired if there is concomitant uveitis, vitreitis, retinitis, or optic neuropathy. In addition, an infectious arteritis affecting the vasculature of the subarachnoid space may occur, result in thrombosis, ischemia, and stroke involving the brain or spinal cord. Diagnostic testing includes serum treponemal and nontreponemal tests and spinal fluid examination to assess for presence of pleocytosis, elevated protein concentration, and CSF Venereal Disease Research Laboratory tests.
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ody or agglutination testing of spinal fluid; uncommonly, the organism may be recovered in CSF culture. (See "Brucellosis: Epidemiology, microbiology, clinical manifestations, and diagnosis".) ●<span>Neurosyphilis – Meningitis and meningovascular disease are manifestations of early neurosyphilis. Clinical manifestations of syphilitic meningitis include headache, confusion, nausea, vomiting, and stiff neck; in addition, cranial neuropathies may occur. Visual acuity may be impaired if there is concomitant uveitis, vitreitis, retinitis, or optic neuropathy. In addition, an infectious arteritis affecting the vasculature of the subarachnoid space may occur, result in thrombosis, ischemia, and stroke involving the brain or spinal cord. Diagnostic testing includes serum treponemal and nontreponemal tests and spinal fluid examination to assess for presence of pleocytosis, elevated protein concentration, and CSF Venereal Disease Research Laboratory tests. (See "Neurosyphilis".) ●Bacterial meningitis – Bacterial meningitis presents acutely with fever, nuchal rigidity, and altered mental status. Typical CSF findings include white blood cel




Bacterial meningitis – Bacterial meningitis presents acutely with fever, nuchal rigidity, and altered mental status. Typical CSF findings include white blood cell count of 1000 to 5000/microL (neutrophil predominance), protein concentration 100 to 500 mg/dL, and glucose concentration <40 mg/dL. The diagnosis may be established via isolation of a bacterial pathogen from CSF or blood cultures. In patients with partially treated meningitis, there is usually minimal effect on the CSF chemistry and cytology findings, but the yield of Gram stain and culture may be diminished.
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ntreponemal tests and spinal fluid examination to assess for presence of pleocytosis, elevated protein concentration, and CSF Venereal Disease Research Laboratory tests. (See "Neurosyphilis".) ●<span>Bacterial meningitis – Bacterial meningitis presents acutely with fever, nuchal rigidity, and altered mental status. Typical CSF findings include white blood cell count of 1000 to 5000/microL (neutrophil predominance), protein concentration 100 to 500 mg/dL, and glucose concentration <40 mg/dL. The diagnosis may be established via isolation of a bacterial pathogen from CSF or blood cultures. In patients with partially treated meningitis, there is usually minimal effect on the CSF chemistry and cytology findings, but the yield of Gram stain and culture may be diminished. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".) ●Focal parameningeal infection (brain abscess, spinal epidural abscess, sphenoid sinusitis) – Clinical m




Focal parameningeal infection (brain abscess, spinal epidural abscess, sphenoid sinusitis) – Clinical manifestations of parameningeal infection may be subacute and nonspecific. Initial evaluation should consist of radiographic imaging (of the brain and/or spinal cord). LP is contraindicated in patients with papilledema or focal symptoms or signs; if it is feasible to obtain CSF, findings may demonstrate elevated protein concentration, low glucose concentration, and pleocytosis. A microbiologic diagnosis may be established culture of material obtained via stereotactic-guided aspiration or surgery.
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l effect on the CSF chemistry and cytology findings, but the yield of Gram stain and culture may be diminished. (See "Clinical features and diagnosis of acute bacterial meningitis in adults".) ●<span>Focal parameningeal infection (brain abscess, spinal epidural abscess, sphenoid sinusitis) – Clinical manifestations of parameningeal infection may be subacute and nonspecific. Initial evaluation should consist of radiographic imaging (of the brain and/or spinal cord). LP is contraindicated in patients with papilledema or focal symptoms or signs; if it is feasible to obtain CSF, findings may demonstrate elevated protein concentration, low glucose concentration, and pleocytosis. A microbiologic diagnosis may be established culture of material obtained via stereotactic-guided aspiration or surgery. (See "Pathogenesis, clinical manifestations, and diagnosis of brain abscess" and "Spinal epidural abscess" and "Chronic rhinosinusitis: Clinical manifestations, pathophysiology, and dia




Viral meningitis (herpes simplex, mumps) – Viral CNS infection usually presents acutely, in contrast to tuberculous meningitis, which is typically subacute. In the setting of viral meningitis, the CSF also typically demonstrates a lymphocytic pleocytosis, elevated protein but normal glucose, and negative Gram stain and culture. Definitive diagnosis of viral meningitis is established via CSF polymerase chain reaction.
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ee "Pathogenesis, clinical manifestations, and diagnosis of brain abscess" and "Spinal epidural abscess" and "Chronic rhinosinusitis: Clinical manifestations, pathophysiology, and diagnosis".) ●<span>Viral meningitis (herpes simplex, mumps) – Viral CNS infection usually presents acutely, in contrast to tuberculous meningitis, which is typically subacute. In the setting of viral meningitis, the CSF also typically demonstrates a lymphocytic pleocytosis, elevated protein but normal glucose, and negative Gram stain and culture. Definitive diagnosis of viral meningitis is established via CSF polymerase chain reaction. (See "Aseptic meningitis in adults".) ●Neoplastic meningitis – Leptomeningeal metastases (LM) are diagnosed in approximately 5 percent of patients with advanced cancer; the most common




Neoplastic meningitis – Leptomeningeal metastases (LM) are diagnosed in approximately 5 percent of patients with advanced cancer; the most common primary tumors associated with development of LM are breast, lung, and melanoma. Clinical manifestations include headache, nausea and vomiting, leg weakness, ataxia, altered mental status, diplopia, and facial weakness. Typical MRI findings include linear and nodular leptomeningeal enhancement; thickening and enhancement of cranial nerves or nerve roots, including the cauda equina, and hydrocephalus. CSF findings include elevated opening pressure, mild pleocytosis, elevated protein and decreased glucose concentrations. The diagnosis of LM is definitively established via identification of malignant cells in the CSF.
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rotein but normal glucose, and negative Gram stain and culture. Definitive diagnosis of viral meningitis is established via CSF polymerase chain reaction. (See "Aseptic meningitis in adults".) ●<span>Neoplastic meningitis – Leptomeningeal metastases (LM) are diagnosed in approximately 5 percent of patients with advanced cancer; the most common primary tumors associated with development of LM are breast, lung, and melanoma. Clinical manifestations include headache, nausea and vomiting, leg weakness, ataxia, altered mental status, diplopia, and facial weakness. Typical MRI findings include linear and nodular leptomeningeal enhancement; thickening and enhancement of cranial nerves or nerve roots, including the cauda equina, and hydrocephalus. CSF findings include elevated opening pressure, mild pleocytosis, elevated protein and decreased glucose concentrations. The diagnosis of LM is definitively established via identification of malignant cells in the CSF. (See "Clinical features and diagnosis of leptomeningeal metastases from solid tumors".) Issues related to CNS disease in patients with HIV infection are discussed further separately. (S




Flashcard 6270135438604

Question
Explain what is a neural network, according to 3Blue1Brown.
Answer
.

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Flashcard 6270137273612

Question
Explain what is gradient descent in the context of ANN.
Answer
.

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Flashcard 6270142516492

Tags
#an-integrated-machine-learning-and-finite-element-analysis-framework #has-images
Question
Why ANNs can be interesting in FEA-based optimisation?
[unknown IMAGE 6270141205772]

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#an-integrated-machine-learning-and-finite-element-analysis-framework
The work of Bisagni and Lanzi [23] recognises the efforts made by other authors to perform a minimum weight optimisation of a stiffened composite panel. Boundary conditions and outputs often included minimum panel strength and the critical buckling load. Inputs include the layup definition as well as stiffener count and dimensions, which means both discrete and continuous variables are involved. To cope with such variables as well as a potential non-convex cost function, a genetic algorithm (GA) is chosen as optimisation algorithm. As this approach is computationally expensive, Bisagni and Lanzi propose an optimisation procedure in which the desired outputs of the structural response are predicted by means of a system of ANNs as shown in Figure 2.12. These networks are first trained on a series of FEM simulations, after which the calculation can be omitted in the optimisation process itself. A separate ANN is trained for each output variable: Pre-buckling stiffness, buckling load, collapse load and even the load-displacement curve. Each ANN featured a relatively simple architecture with only one HL and a limited number of nodes. The only ANN with more than 10 nodes is the load-displacement curve predictor which is intuitive due to the various inputs such a curve depends on. The networks consistently predicted the desired results with more than 75% of training and test data within a 4% error margin. The improvement in computational time of this approach in comparison with an FEA-only optimisation is around an order of magnitude.
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Flashcard 6270152477964

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#an-integrated-machine-learning-and-finite-element-analysis-framework #has-images
Question
Discuss about the prediction of experimental results directly with ANNs rather than with a FE model.
Answer


A imagem abaixo foi retirada de Fu et al.



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Flashcard 6270157196556

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#an-integrated-machine-learning-and-finite-element-analysis-framework #has-images
Question
Describe the steps traditionally used to derive the material behaviour and an alternative approach that use ANNs.
Answer


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Flashcard 6270167682316

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#an-integrated-machine-learning-and-finite-element-analysis-framework #has-images
Question
Discuss about the use of ANNs when modelling elasto-plastic behaviour of 2D plane strain shell in the work of Ghaboussi et al..
Answer


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#an-integrated-machine-learning-and-finite-element-analysis-framework
Multiple demonstrations of ANN constitutive models are presented in Javadi et al. [33]. Similar to the work of Ghaboussi et al., the ANN is trained to predict the stress-strain behaviour based on the current state and a given increment size. Javadi et al. implemented a trained ANN in each element in an FE model as a substitution for the conventional constitutive material model. Apart from the computational procedure in each element, the analyses are performed by a conventional FE solver. The approach is tested on a 2-D beam with 10 elements and a transverse end-load, where the ANN is shown to be as accurate as the regular FE analysis. Furthermore, a quarter segment of a 2-D thick cylinder shell with nine 8-node elements subject to a distributed load is investigated. Again, an excellent agreement with both theoretical and FEM results is achieved with the ANN constitutive model. Finally, an analysis is performed involving the more complex
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#an-integrated-machine-learning-and-finite-element-analysis-framework
constitutive behaviour of an embankment consisting of a non-linear Mohr-Coulomb soil material. The ANN, trained on triaxial experimental tests results, is shown to be potentially more robust than an FEA as it is based directly on the experiments instead of a mathematical model that is subject to assumptions.
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Flashcard 6270175808780

Tags
#an-integrated-machine-learning-and-finite-element-analysis-framework #has-images
Question
Discuss about the autoprogressive training algorithm proposed by Ghaboussi et al..
[unknown IMAGE 6270174498060]

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Flashcard 6275107523852

Question
the introduction of new ideas or methods
Answer
innovation n. 2 [U]

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Flashcard 6275109358860

Question
when new or better products are designed and developed, or the new or better product itself
Answer
product innovation [C, U]

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Flashcard 6275111193868

Question
An innovative product, method, process, etc. is new, different and better than those that existed before.
Answer
innovative adj. 1

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Flashcard 6275113028876

Question
using or developing new and original ideas and methods
Answer
innovative adj. 2

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