Multicenter Evaluation of Clinical Diagnostic Methods for Detection and Isolation of Campylobacter spp. from Stool

Abstract

The use of culture-independent diagnostic tests (CIDTs), such as stool antigen tests, as standalone tests for the detection of Campylobacter in stool is increasing. We conducted a prospective, multicenter study to evaluate the performance of stool antigen CIDTs compared to culture and PCR for Campylobacter detection. Between July and October 2010, we tested 2,767 stool specimens from patients with gastrointestinal illness with the following methods: four types of Campylobacter selective media, four commercial stool antigen assays, and a commercial PCR assay. Illnesses from which specimens were positive by one or more culture media or at least one CIDT and PCR were designated "cases." A total of 95 specimens (3.4%) met the case definition. The stool antigen CIDTs ranged from 79.6% to 87.6% in sensitivity, 95.9 to 99.5% in specificity, and 41.3 to 84.3% in positive predictive value. Culture alone detected 80/89 (89.9% sensitivity) Campylobacter jejuni/Campylobacter coli-positive cases. Of the 209 noncases that were positive by at least one CIDT, only one (0.48%) was positive by all four stool antigen tests, and 73% were positive by just one stool antigen test. The questionable relevance of unconfirmed positive stool antigen CIDT results was supported by the finding that noncases were less likely than cases to have gastrointestinal symptoms. Thus, while the tests were convenient to use, the sensitivity, specificity, and positive predictive value of Campylobacter stool antigen tests were highly variable. Given the relatively low incidence of Campylobacter disease and the generally poor diagnostic test characteristics, this study calls into question the use of commercially available stool antigen CIDTs as standalone tests for direct detection of Campylobacter in stool. Campylobacter infection continues to be a major public health problem. Campylobacter jejuni and Campylobacter coli are pathogens transmitted commonly through food, causing an estimated 1.3 million cases of illness per year in the United States (1), and yet diagnosis can be challenging because the organism is difficult to isolate, grow, and identify. Recent reports describing clinical laboratory practices for Campylobacter diagnostics in Pennsylvania (2) and the Foodborne Diseases Active Surveillance Network (FoodNet) sites (3) highlight the wide range of testing practices in use; currently, no best-practice clinical or public health laboratory guidelines exist for laboratory diagnosis of Campylobacter infections. Direct plating onto a Campylobacter selective medium, followed by incubation at 42°C under microaerobic conditions for 72 h, has long been considered the "gold standard" for diagnosis (4).The use of culture-independent diagnostic tests (CIDTs) for Campylobacter testing on stool samples is increasing, which may have important implications for both patient management and public health surveillance efforts (5). Stool antigen tests to directly detect Campylobacter in fecal samples are fast and generate sameday results, but concerns regarding speci...

MALDI-TOF identification of Campylobacter isolated from patients consulted in private laboratories in France

“…Our study also showed that Campylobacter infections were more prevalent in male (59.4%) than in female (40.6%) patients. This is corroborated by previous studies, which reported high campylobacter prevalent in male patients compared to female patients (Friedman et al, 2000;Fitzgerald et al, 2011). However, some studies found that females have higher risk of getting infected by Campylobacter than males (Gillespie et al, 2006;Karikari et al, 2017).The isolated strains in our study showed considerable resistance to ampicillin (26.4%), to tetracycline (30.5%) whereas the resistances to ciprofloxacin, erythromycin and gentamicin were relatively low (0.5-1%).…”

Evaluation of the Diagnostic Accuracy of Two Immunochromatographic Tests Detecting Campylobacter in Stools and Their Role in Campylobacter Infection Diagnosis

“…The C-reactive protein was logically increased in the majority of the patients. The prevalence of infection in this study is quite high compared to other studies described in the literature (14). This is most certainly due to our recruitment of only emergency unit patients, reflecting a community recruitment compared to other studies in which the stools of patients hospitalized in all departments of the hospital were included (9, 10).…”

New Developments in Rapid Diagnostic Testing for Children

“…Unfortunately, a large multicenter study evaluated 4 Campylobacter antigen assays and found that despite relatively high specificity (>95%), the positive predictive value was only 36% to 51%. 21 Based on these results, the use of Campylobacter antigen assays as stand-alone tests is not recommended. Antigen testing has also been used for detection of viral and parasitic causes of gastroenteritis, including adenovirus 40/41, rotavirus, Giardia lamblia, and Cryptosporidium.…”