Comparison of Sensitivity and Specificity of Direct Microscopy and Culture Methods as Diagnostic Tool for for Diagnosing Trichomoniasis among Females of Reproductive Age, Port Harcourt, Nigeria

Abstract

Trichomoniasis is a sexually transmitted parasitic disease caused by Trichomonas vaginalis and is distributed worldwide. This study was a comparison of direct microscopy and culture methods in diagnosis of trichomoniasis in Port Harcourt, Nigeria. A descriptive cross-sectional study was adopted involving the detection of Trichomonas vaginalis using culture and direct microscopy techniques among females attending Rivers State University Teaching Hospital (RSUTH), Port Harcourt after ethical approval was sought and obtained. Samples were analyzed using direct wet preparation and culture technique. Sociodemographic data were obtained using well-structured questionnaires. A total of 650 specimens were examined, 450 were urine samples and 200 were high vaginal swab (HVS) samples which were examined directly under the microscope and cultured in Trichomonas medium (Oxoid CM0161) at 37ºc for 7 days.  Out of 450 urine specimens examined, 4 were positive using direct microscopy with a prevalence of 0.9% (P>0.05), while 22 were positive using culture technique with a prevalence of 4.9% (P<0.05). 5 out of 200 HVS were positive using direct microscopy with a prevalence of 2.5% (P>0.05), while 18 were positive using culture technique with a prevalence of 9% (P<0.05). Direct microscopy and culture techniques recorded a moderate agreement (κ=0.412) and was statistically significant (P<0.05). Culture of HVS recorded the highest sensitivity of 94.44% with specificity of 99.45%, while direct microscopy of HVS recorded a sensitivity of 80% with specificity of 99.49%. Culture of urine recorded a sensitivity of 90.91% with specificity of 99.53%, while direct microscopy of urine recorded a sensitivity of 75% with specificity of 99.78%. Conclusion: It is recommended that culture should be incorporated as an additional method for routine testing of Trichomonas vaginalis in our health care centres for improved monitoring and control of the disease.