Comparative evaluation of Ziehl-Neelsen staining, Fluorescent staining and Culture with Polymerase Chain Reaction in the diagnosis of Genital Tuberculosis in infertile women - One year cross sectional study at Tertiary Care Hospital,Belagavi

Abstract

Background: Tuberculosis is a chronic infectious disease caused by Mycobacterium Tuberculosis (Mtb).Female Genital tuberculosis (FGTB) is associated with infertility. Still, the true epidemiology of this disease remains unknown due to lack of highly sensitive and specific tests. Genital tuberculosis not only causes tubal obstruction and dysfunction but also impairs implantation due to endometrial involvement and ovulatory failure from ovarian involvement. Clinical diagnosis of FGTB is challenging due to varied clinical presentation. Microscopy and Culture to detect Mycobacteria though specific have low detection rate due to paucibacillary nature of FGTB.Molecular detection of Mtb DNA by Polymerase chain reaction (PCR) is rapid and sensitive being immensely employed to diagnose FGTB. Objective: To compare the diagnostic ability of Ziehl-Neelsen staining, Fluorescent staining and Culture with Polymerase Chain Reaction in the diagnosis of Genital Tuberculosis in infertile women. Methodology: The Cross-sectional study for one year duration (Jan-Dec 2015) was conducted on eighty cases of female infertililty at KLE’S Dr. Prabhakar Kore Hospital and Research Center,Belagavi who met the inclusion and exclusion criteria, after obtaining their informed consent. Institutional Ethical Clearance (MDC/DOME/318) was sought.Endometrial tissue sample was collected in a sterile universal container containing normal saline.The sample was homogenised and subjected for Ziehl-Neelsen staining, Culture(Lowenstein-Jensen media) and DNA TB-PCR .The samples were processed in Biosafety cabinet II , adhering to Universal safety precautions in the department of Microbiology, JNMC, Belagavi. Results and Discussion: Out of 80 Samples, 39 cases were clinically suspected to have Genital TB and the remainder had no clinical suspicion. Out of 80 samples tested , Acid-fast bacilli was not detected in the microscopy.No organisms were grown in culture.DNA TB-PCR was positive in 4 of the 39 clinically suspected cases of FGTB while no Mtb DNA was detected in other 51 infertile cases who did not have clinical suspicion. Conclusion: FGTB being paucibacillary, diagnosis by Conventional methods (Microscopy and Culture) have limitations and low detection rate.Culture (8 weeks) is gold standard test. Molecular test like PCR which is rapid and more sensitive may help in early diagnosis of FGTB and can be a chief tool to confirm diagnosis in clinically suspected cases. False negative PCR was a limitation in this study.