Diagnosis of Helicobacter pylori infection in a high-prevalence pediatric population: a comparison of 2 fecal antigen testing methods and serology.
OBJECTIVE
Accurate methods for diagnosing active Helicobacter pylori infection in children have been limited to invasive or time-consuming techniques. Recently, fecal antigen testing has been used successfully for the diagnosis of H pylori infection in the pediatric population. We compared 2 monoclonal fecal antigen diagnostic methods in a population of children with a suspected high prevalence of H pylori infection. We also assessed the diagnostic performance of H pylori immunoglobulin G serology.


METHODS
In a cross-sectional study of African refugee children (<16 years) we compared an immunochromatographic technique (ICT) and serology with a monoclonal fecal antigen enzyme immunoassay (MFAT) method for the detection of active H pylori infection. Following the manufacturer's instructions, an optical density of >or=0.190 was used as a cutoff for MFAT. Sensitivity, specificity, and positive and negative predictive values were calculated.


RESULTS
Of the 193 eligible children enrolled, active H pylori infection was detected in 149 of 182 (81.9%) in whom MFAT was performed. The prevalence of active infection increased with age; children with active infection were significantly older, and there were no sex differences. ICT and serology underperformed in comparison with MFAT (ICT sensitivity 74.6%, specificity 63.6%, positive predictive value 89.8%, negative predictive value 36.8%; and serology sensitivity 57.9%, specificity 77.4%, positive predictive value 92.0%, negative predictive value 29.9%).


CONCLUSIONS
Monoclonal enzyme immunoassay fecal antigen testing is a practical and feasible alternative to traditional invasive diagnostic methods in high-prevalence pediatric populations. Neither immunochromatography nor serology is useful for the diagnosis of active H pylori infection in these children.
Cherian
Sarah
S
School of Paediatrics and Child Health, University of Western Australia, Princess Margaret Hospital for Children, Perth, WA, Australia.
Burgner
David P
DP
Carson
Christine F
CF
Sanfilippo
Frank M
FM
Cook
Angus G
AG
Forbes
David A
DA
D000293:Adolescent; D000367:Age Factors; D000942:Antigens, Bacterial / Q000032:analysis*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005243:Feces / Q000382:microbiology*; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000453:epidemiology; D016480:Helicobacter pylori / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods / Q000592:standards; D007074:Immunoglobulin G / Q000097:blood*; D007223:Infant; D008297:Male; D011237:Predictive Value of Tests; D015995:Prevalence; D012036:Refugees; D012680:Sensitivity and Specificity; D012698:Serologic Tests / Q000379:methods / Q000592:standards
D000942:Antigens, Bacterial; D007074:Immunoglobulin G