Indian Pediatrics 1998; 35:768-770 

Campylobacter jejuni Diarrhea

Diarrhea is an important cause of mortality and morbidity in infants and young children in the developing countries. Continuous monitoring of acute diarrheal disease led to the discovery of new enteropathogens. Listed among these is Campylobacter jejuni(1). C. jejuni has been established as an agent of bacterial enteritis. The pathogenic mechanism of Campylobacter enteritis is not yet clear, though the production of enterotoxin, cytotoxin and other virulence factors have been reported(2). The present study was undertaken to find out; (i) the prevalence of C. jejuni and C. coli in children  < 5 years) in subjects with diarrhea and without diarrhea in northern part of Karnataka, and (ii) determine the enterotoxin production and antibiotic sensitivity pattern of the isolates.

Subjects and Methods

Patients with acute diarrhea (defined as passage of at least 3 liquid stools/day) either hospitalized or attending the Out Patient Department were included in the study. The patients were so selected that the specimen was obtained prior to any antibiotic therapy and within 72 hours of onset of diarrhea. Children attending hospital with problems other than gastrointestinal served as nondiarrheal controls. A total of 697 children under 5 years age suffering from acute diarrhea attending the District Hospitals, Bijapur and Gulbarga were selected for the study. The stool samples from diarrheal cases and controls were processed immediately or in case of possible delay, samples were brought in Carry-Blair transport medium.

The samples were inoculated on Mueller-Hinton agar supplemented with Butzler's antibiotics (Oxoid SR 85 and H: media Lab, Bombay) and 10% defibrinated sheep blood. The plates were incubated at 42^oC for 48 hours under microaerophilic condition which was achieved by burning few drops of alcohol or burning candle in candle jar.

The typical colonies appearing on plates were subjected to morphological and biochemical studies. The colonies were subjected to Gram's staining (using Carbol fuchsin as counter stain) and motility testing. Pleomorphic (5, comma, girdle shaped) organisms showing darting or corkscrew. type of motility were further identified and confirmed as Campylobacters if they were catalase, oxidase positive, sensitive to nalidixic acid (30 µg) and grew in 1% glycine. Hippurate hydrolysis test was employed to differenetiate C. jejuni (positive) from C. coli (negative).

All the stool samples were smeared and stained by Gram's staining using Carbol fuchsin as counter stain to detect pleomorphic Campylobacters. The stool samples were also screened for other enteropathogens and parasites as per standard procedures(3).

All C. jejuni isolates were subjected to antibiotic sensitivity test using standard disc diffusion method. Twelve strains of C. jejuni isolated from patients were tested in ligated ileal loops of albino rats for the production of enterotoxin(4).

Results and Discussion

Of the 697 diarrheal stool samples processed for Campylobacters, C. jejuni was isolated from 22 cases (3.2%) (Table I). Isolation was found to be more in 1-5 years age group (4.7%) in comparison to infants (1.6%). In all cases C. jejuni was isolated in pure culture. It was observed that when campylobacters were seen in direct smear examination, they always grew upon culture. C. coli was not encountered in the study. In C. jejuni caused diarrhea cases, apart from watery diarrhea, other clinical features were abdominal pain (55%) and fever (36%). One patient had moderate degree of dehydration.

The studies conducted in other parts of India, show variable isolation rates ranging from 1.5% to 16.4%(5,6). There are conflicting reports about the prevalence of C. jejuni in healthy children. In studies conducted in Bangalore(5), Vellore(7) and Calcutta(8), C. jejuni was found in similar numbers in both diarrheal and nondiarrheal children. In the present study, C. jejuni was not isolated . from any of the controls. A similar observation was made by other workers(6,9). The number of healthy children screened for C. jejuni in this study were less when compared to the number of diarrheal cases.

The susceptibility of C. jejuni isolates to various antibiotics is given in Table II. All the isolates were sensitive to erythromycin, gentamicin, nalidixic acid and norfloxacin. Ten isolates were resistant to ampicillin and tetracycline, while 16 isolates exhibited resistance to cotrimaxozole. The antibiotic sensitivity pattern of C. jejuni was similar to the earlier reports(10-11).

The pathogenesis of C. jejuni is under study for many years. The standard animal models used for other enteropathogens have yielded negative or inconsistent results(2). Some workers have reported that C. jejuni caused fluid accumulation in rat ilealloops(4,12). In the present study, 12 C. jejuni strains were tested in rat ileal loop. Of these, 10 produced fluid accumulation in the range of 0.25-0.45 ml/cm of gut, while 2 strains failed to produce fluid accumulation. It seems that in addition to enterotoxin, other factors (cytotoxin) also contribute towards pathogenicity.

Like any other enteropathogen, the clinical picture of Campylobacter enteritis varies from asymptomatic secretion or mild symptoms to severe disease. Enteritis due to C. jejuni is usually mild and self limiting in most cases. Antibiotic therapy may be needed in severe cases or in patients with prolonged illness. In cases of clinical urgency, rapid presumptive diagnosis can be made by direct stool examination. In the absence of culture facilities, gentamicin, norfloxacin or nalidixic acid can be used for treatment.

 

The present study shows that C. jejuni is prevalent in northern part of Karnataka and enterotoxin production is one of the pathogenicity factors resulting C. jejuni diarrhea.

Acknowledgement

The authors thank the Director and Dr. G. Balakrish Nair, NICED, Calcutta for providing training and assistance during the study.

 

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