Comparison of Microscopy, Boeck and Drbolav’s Stool Culture Medium and Bichro-latex Antibody Test with A Reference Elisa Antigen Test for E. histolytica Diagnosis in Calabar, Nigeria

Abstract

Objective: Amoebiasis is a parasitic infection caused by E.histolytica, accurate diagnosis of E. histolytica is important in the treatment of amoebiasis and to avoid preventable costs. The study objective is to compare different diagnostic methods used in the diagnosis of amoebiasis for detection of E.histolytica parasite. Materials and Methods: Faecal and serum specimens of 200 patients defined as symptomatic (diarrhea and dysentery) and asymptomatic (a case history of E.histolytica infection) was used for the study .Stool specimen was examined with microscopy, cultured in Boeck and drbolav’s medium and anti-E. histolytica antibodies were investigated using a latex slide test. Stool samples were also examined by immunoassay methods for specific antigens which is the reference standard for comparison. Result: Two hundred (200) samples examined for E.histolytica parasite 12(6.0%) were positive in in microscopy,34(17%) in bichro-latex antibody test and 6(3.0%) in Boeck and drbolav’s culture medium. The three test methods showed significant detection of E.histolytica parasite(p<0.05). Microscropic method detected 100% of E.histolytica infection in symptomatic patients and Boeck and Drbohlav’s culture medium detected 33.3%. However, the method of diagnosis is not associated with the diagnosis E.histolytica infection in asymptomatic and symptomatic Patients(p>0.05).The diagnostic precision of the microscopy diagnostic method showed that sensitivity was 40.2%, specificity was 82.3%, PPV 39.6% and NPV 70.4% .The sensitivity was 86.6%, specificity was 70.6% PPV 87.6% and NPV 75.6% for bichro-latex antibody test and The sensitivity was 20.6 %, specificity was 50.6 %, PPV 34.6%, NPV 61.2% for Boeck and Drbohlav’s culture medium Conclusion: The result from the comparison of the three diagnostic methods for E.histolytica parasite indicate high sensitivity and specificity for bichro-latex antibody test when compared with the other methods. however, in areas were molecular technology such as Polymerase chain reaction and enzyme linked immunosorbent assay is not available, bichro-latex antibody assay is recommended. although,microscopic examination can be used in diagnosis of amoebiasis in geographical areas with technological limitation in health.