on 12-May-2022 (Thu)

The clinical manifestations of infections caused by all of the Campylo- bacter spp. that cause enteric illnesses appear identical; C. jejuni infection may be regarded as the prototype

Acute enteritis is the most common presentation of C. jejuni infection. Symptoms may last from 1 day to 1 week or longer. Often, there is a prodrome with fever, headache, myalgia, and malaise 12 to 24 hours before the onset of intestinal symptoms. 143 In some patients, the constitutional symptoms may coincide with the intestinal phase or, less often, may follow it. The most common symptoms are diarrhea, malaise, fever, and abdominal pain. 143–14

Diarrhea may range in severity from loose stools to massive watery or grossly bloody stools. In any patient, the entire spectrum of diarrhea may be seen. For most patients, there are 10 or more bowel movements on the worst day of the illness

Abdominal pain is usually cramping and is relieved by defecation; it may be the predominant manifestation of illness.

Cam- pylobacter enteritis is frequently self-limiting, with a gradual resolution of symptoms over several days; however, illness lasting longer than 1 week occurs in 10% to 20% of patients seeking medical attention, and relapse may be seen in another 5% to 10% of patients who do not receive treatment. 44,143–146

Infection also may be manifested as an acute colitis, with symptoms of fever, abdominal cramps, and bloody diarrhea persisting for 1 week or longer. 75,145

Fever may be low grade or consist of daily peaks above 40°C (104°F). Initially, stools may be watery, but as the illness progresses they may become frankly bloody; tenesmus is a common symptom. In the most severe forms, patients appear very ill, and toxic megacolon has been reported. 147

Because of the propensity of Campylobacter infection to affect young adults and the characteristic clinical presentation, it may be readily confused with ulcerative colitis or Crohn disease. 75,143

Because of the often fastidious nature of these organisms, 148,149 a single negative culture does not rule out infection, especially if optimal filtration methods are not used for primary isolation of a pathogen

Occasionally, acute abdominal pain may be the major or only symptom of infection. 150 Although any quadrant of the abdomen may be affected, patients most often complain of pain in the right lower quadrant. As with Yersinia enterocolitica and Salmonella enteritidis, C. jejuni may cause pseudoappendicitis. 44,143

Campylobacter infection occasionally may present solely as a gastrointestinal hemorrhage. 151

Bacteremia has been noted in less than 1% of patients with C. jejuni infection. In part, this low frequency reflects the fact that physicians rarely perceive diarrheal illness as an indication for blood culture, even when fever is present. Nevertheless, bacteremia appears to be more common in infections in people at the extremes of age. 58,155,156

Meningitis and endocarditis are rare manifestations of C. jejuni infection.

In general, three patterns of extraintestinal C. jejuni infection have been noted. 157

First, there may be a transient bacteremia in a normal host with acute Campylobacter enteritis. The bacteremia may be discovered several days after blood cultures are obtained, by which time the patient usually has completely recovered. The course is benign, and no specific treatment based on the positive blood culture result is usually indicated.

Second, there may be a sustained bacteremia or deep focus of infection in a previously normal host; usually the patient has an acute enteritis as well. The C. jejuni isolates are generally relatively or absolutely serum resistant. 157 Bacteremia usually has its origin in the intestinal tract inflammation and responds to antimicrobial therapy

Third, sustained bacteremia or deep infection may occur in an immunocompromised host; many such patients do not have an acute enteritis. C. jejuni isolates are usually serum sensitive. 157 However, as with other gram-negative bacteria, C. jejuni bacteremia may produce fever and shock. 158 Antimi- crobial therapy, which may need to be prolonged, is required for elimina- tion or suppression of this infection

There have been infrequent reports of C. jejuni infections manifesting as acute cholecystitis, 160 pancreatitis, 161 and cystitis. 162

People with immunoglobulin deficiencies often develop prolonged, severe, and recurrent C. jejuni infections, 131,132 often with bacteremia and other extraintestinal manifestations such as erysipelas-like skin lesions or osteomyelitis. 163

C. jejuni infections have been associated with multiple postinfec- tious sequelae, especially GBS but also reactive arthritis, irritable bowel syndrome, and immunoproliferative disorders of the small intestine

GBS is a strongly associated but uncommon consequence of C. jejuni infection (estimated at 1 case per 2000 infections) that usually occurs 2 or 3 weeks after the diarrheal illness. 166,167 From 20% to 50% of GBS cases follow C. jejuni infections, reflecting in part the high incidence of these infections. 166–170

A particular group of C. jejuni organisms marked by LPS serotype O:19 is overrepresented among people who develop GBS. 170–172 A recent study demonstrated that C. jejuni O:19 chaperone proteins share high primary sequence homology with heat shock proteins found on human peripheral nerves; these structures as well as capsular and LPS glycolipids may be involved in the molecular mimicry trigger- ing GBS. 173 Serotype O:41 has also been implicated, and other sporadic cases may be due to specific C. jejuni strains with sialylation of their LPS molecules. 174–176

Postinfectious reactive arthritis may occur up to several weeks after infection, and prolonged rheumatic symptoms have also been reported. The relation of this phenomenon to the presence of HLA-B27 histocompatibility antigens is not clear. 177–179

Myopericarditis, 181,182 hepatitis, 183 cellulitis, 184 interstitial nephritis, the hemolytic-uremic syndrome, and IgA nephropathy 185 are other reported complications

Although C. fetus may occasionally cause diarrheal disease, it has the propensity to cause dissemination, including bacteremia, endovascular infections, and cellulitis, and may do so in the absence of intestinal symptoms. 141,186

C. fetus infections may cause intermittent diarrhea or nonspecific abdominal pain without localizing signs. The diarrheal illness may manifest exactly like C. jejuni infection and is more common than was suspected several years ago. Clinical manifestations are similar and sequelae uncommon. Nearly all affected patients survive the infections when appropriate antibiotic treatment is given and usually do well without antibiotic treatment.

C. fetus also may cause a prolonged relapsing illness characterized by fever, chills, and myalgias, in which a source of infection cannot be demonstrated. 142,187 Occasionally, secondary seeding of an organ will occur, leading to a more complicated infec- tion 187,188 and sometimes to a fulminant, fatal course

C. fetus infections appear to have a predilection for vascular sites; vascular necrosis occurs in patients with endocarditis and pericarditis resulting from this organism. 189–191 Mycotic aneurysms of the abdominal aorta and, rarely, peripheral arteries also occur. 192 Thrombophlebitis may be associated with C. fetus bacteremia, but whether it is the primary event or a secondary manifestation of the infection is uncertain. Patients with a bacteremic illness without localization should be carefully evaluated for the presence of septic thrombophlebitis, because the response is good when this condition is treated with appropriate antibiotics

Central nervous system (CNS) infections with C. fetus occur in neonates and adults. The prognosis is poor for premature infants, but five of six full-term neonates in one series survived infection. Infection is manifested as a meningoencephalitis with a cerebrospinal fluid polymorphonuclear pleocytosis

Meningoencephalitis is also the most common CNS manifesta- tion of C. fetus infection in adults. 194 Cerebrovascular accidents, sub- arachnoid hemorrhages, and brain abscesses also occur. The prognosis is better in adults than in neonates, with a survival rate of approximately 67%, although neurologic sequelae are frequent.

Antibiotic resistance to fluo- roquinolones may develop in immunocompromised patients who receive monotherapy regimens. 197 Nevertheless, in other patients, self-limiting bacteremia without any sequelae has been observed. Hypogammaglobu- linemic patients may have persistent bacteremia and local symptoms unless given chronic suppressive therapy with antibiotics.

C. fetus is found in multiple animals and animal products, mainly cattle and sheep, which are probably the main source of human infection. 198

Foodborne sources of infection likely include raw milk products, raw liver, and raw meat of such animals. 199 Similarly, reptiles may carry a different group of C. fetus strains, 200,201 and human infections with these organisms have been reported as well. 198,202 Reports of a cluster of C. fetus cases among men who have sex with men suggest the possibility of person-to-person transmission. 20