Detection of Mycobacterium Tuberculosis among Infertile Patients Suspected with Female Genital Tuberculosis

Abstract

Female genital tuberculosis (FGTB) is a symptomless disease that evidences itself only when it is investigated for infertility. Demonstration of the etiologic agent by H & E staining or Z-N staining for acid fast bacilli, smear microscopy, culture of menstrual blood, urine and sputum were often unsuccessful. We therefore, proposed to use the endo-ovarian tissue biopsies and pelvic aspirated fluids for the detection of FGTB among infertile women by conventional versus genotypic methods. A prospective case-control study was undertaken. A total of 302 specimens were collected from 202 infertile women highly suspected of having FGTB on laparoscopic examination and from 100 control women of reproductive age. Out of these 302 specimens, 150 (49.67%) were premenstrual endometrial tissue biopsies (ETBs), 95 (31.46%) were ovarian tissue biopsies (OTBs) and 57 (18.87%) were pelvic aspirated fluids (PAFs). All specimens tested by conventional/ phenotypic methods were later compared with multi-gene/ multi-primer PCR (multi-gene PCR) method using four sets of primers for the detection of Mycobacterium tuberculosis (MTB) DNA in a single tube-single step reaction and correlated with laparoscopic findings. The presence of MTB DNA was observed in 49.5% of ETBs, 33.17% of OTBs and 5.44% of PAF specimens collected from highly suspected FGTB patients. All control women were confirmed as negative for tuberculosis. The conventional methods showed 99% to 100% specificity with a low sensitivity, ranging from 21.78% to 42.08% while H & E staining showed a sensitivity of 51.48%. Multi-gene PCR method was found to have a much higher sensitivity of 70.29% with MTB64 gene, 86.63% with 19kDa antigen gene at species and TRC4 element at regional MTB complex level and 88.12% with 32kDa protein gene at genus level (Pearson χ2 =214.612, 1df, McNemar's test value <0.0001). The specificity of multi-gene PCR was 100%. We suggest site specific sampling, irrespective of sample type and amplification of the 19kDa antigen gene in combination with TRC4 element as a successful multi-gene PCR method for the diagnosis of FGTB and differentiation of mycobacterial infection among endo-ovarian tissue biopsies and PAFs taken from infertile women.