A surveillance system for pigbel in Papua New Guinea, based on a clinical case definition and laboratory confirmation
- Author:
Trevor Duke
- Publication Type:Journal Article
- From:
Papua New Guinea medical journal
2019;62(3-4):114-121
- CountryPapua New Guinea
- Language:English
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Abstract:
Summary
AIMS: This study aimed to evaluate a surveillance system for pigbel (enteritis necroticans), an enteric disease caused by Clostridium perfringens type C beta-toxin. Pigbel was formerly endemic in Papua New Guinea. Surveillance was based on a standardized clinical case definition, plus laboratory confirmation using a new assay for Clostridium enterotoxin that may be identified in intestinal secretions or stool. METHODS: Patients admitted to the Nazarene Hospital in the Jiwaka Province were eligible for inclusion if they had severe abdominal pain of less than 2 weeks’ duration. A standardized case definition of pigbel was used to distinguish cases of acute abdominal pain very likely to be due to pigbel from cases likely to be accounted for by other diagnoses. Children enrolled in the study were tested with a new ELISA (enzyme-linked immunosorbent assay) for Clostridium perfringens beta-toxin. The number and types of samples tested depended on the clinical features and illness severity, and included gastric aspirate, stool and intestinal fluid if surgery was required. RESULTS: Between October 2012 and January 2015 105 patients with acute abdominal pain were admitted. The median age (interquartile range) was 5 (2- 6) years. 48 children met the standardized criteria for the clinical diagnosis of pigbel. 34 of 67 children tested with ELISA fulfilled the criteria for clinical pigbel, of whom 12 tested positive and 22 negative. The sensitivity of the ELISA test against the clinical diagnosis was therefore 35%. The test was positive in 4 children with abdominal pain who did not fulfil all the clinical criteria for pigbel, suggesting that they had a mild form of the disease. There were 4 surgically confirmed patients who were ELISA negative. In total, laboratory or surgically confirmed pigbel was found in 20 patients, but it is likely that there were others with pigbel among the 105 patients with acute abdomen. 5 of the study children died. CONCLUSIONS: The ELISA test for Cl. perfringens beta-toxin can be a useful confirmatory test and can help to validate the clinical impression of pigbel. However, the sensitivity is low, even in children who are likely to have pigbel, and therefore a negative test cannot rule out the diagnosis. Because the differential diagnosis of the clinical features of pigbel is broad, having the combination of clinical and laboratory-based surveillance for pigbel would help monitor the true burden of disease, and could be used to guide public health interventions.
