Menstrual Blood versus Endometrial Biopsy in Detection of Genital Tuberculosis by Conventional Microbiological Diagnosis in An Endemic Region

Background: India has a high Tuberculosis (TB) burden, amounting to one-fourth of the global TB prevalence.Genitourinary TB is the second most common type of Extra-pulmonary tuberculosis (EPTB).Female genital tuberculosis (FGTB) often leads to infertility; effective and early diagnosis is therefore very crucial.The objective of this study was to find out the correlation between microscopy and culture positivity in menstrual blood and endometrial biopsy samples for the diagnosis of FGTB.Methodology: In this retrospective study, all endometrial biopsy and menstrual blood specimens from clinically suspected cases of FGTB, received in the Mycobacteriology lab during six months duration (November 2022 to April 2023), were analysed.These were screened for acid fast bacilli (AFB) by Ziehl Neelsen staining (ZN staining) and subjected to culture for Mycobacterium tuberculosis on Lowenstein Jensen medium.Results: Of the total 194 menstrual blood samples received during this period, 22 (11.34%) were positive for AFB.Of these, 77/194 were subjected to culture, of which 17 (13.09%) were positive.Of the 598 endometrial biopsy samples, only 2 (0.33%) were positive for AFB and 2 (0.33%) were positive on culture.Only one sample was positive by both staining and culture.The rate of confirmation of the diagnosis of FGTB by microscopy and/or culture of menstrual blood samples or endometrial biopsy samples was found to be 23/194 (~11%) and 3/598 (0.5%), respectively.Microscopy and culture results were found to be correlated for 99.66% and 90.90% for endometrial biopsy and menstrual blood samples, respectively.Limitations of this study included reliance on retrospective data.Data would have been more definitive if menstrual blood and endometrial biopsy samples were obtained from the same patients, but this was not feasible in the current hospital setting.Conclusions: This study indicates a reliable correlation between microscopy and culture in both samples, signifying that either technique can be used to support clinical diagnosis and hence effective management.