Early diagnosis of female genital TB can reduce morbidity

Dr AG Radhika, CNS Columnist
Photo credit: CNS: citizen-news.org
Tuberculosis (TB) is an important health problem in the low and middle income countries. Pulmonary TB is estimated to have affected about 14 million people in India, most of who are in the reproductive age group. About 12% of women with pulmonary TB also suffer from female genital TB (FGTB). FGTB constitutes almost 9% of extra-pulmonary cases of TB and 13% of gynaecological admissions in India. Infertility is the most frequent clinical presentation of FGTB (43%-74%). 

Other symptoms include increased menstrual cycle length (54%), amenorrhoea (14%), increased menstrual bleeding (19%), abdominal pain (42.5%), pain during sexual contact (5%-12%) and dysmenorrhoea (12%-30%).

In almost all cases of genital TB, fallopian tubes are the initial site of involvement followed by endometrium (79%). 

It is an accepted fact that one of the most important effects of genital TB in women is the physical and mental agony/morbidity caused due to infertility. Even today, it is difficult to establish its diagnosis since it goes largely unsuspected due to lack of classical symptoms and the pauci- bacillary (low bacterial load) nature of the disease. At present hardly 2%-4% of the cases are diagnosed as against expected values of 10%-19%.

Investigations of the infertile couple entail invasive biopsies, radiological investigations for tubal patency and diagnostic/ operative surgical procedures. Tubal and endometrial damage due TB is almost always irreversible affecting the fertility prospects. This leaves one to consider options of in-vitro fertilisation/surrogacy or adoption - each with its own financial and emotional burden.

Early accurate diagnosis of female genital TB would certainly be of great advantage since the morbidity due to tubal and endometrial damage (and the clinical effects thereof) could be largely prevented by early initiation of treatment. As per the existing practice, tissue sample is required for establishing diagnosis. Obtaining sample of endometrium is the least invasive technique of obtaining sample for investigation. Samples of peritoneal lesions can also be obtained through laparoscopy.

A spectrum of clinical presentations add to varying outcomes at imaging, laparoscopy, histopathology, bacteriological and serological tests, and result in the diagnostic challenge of FGTB. The diagnosis is confirmed by the following tests - AFB smear, histology, BACTEC and/or Lowenstein-Jensen culture. Result is considered positive if any one of the tests is positive for AFB. The bacilli are rarely demonstrable in this pauci-bacillary disease; histopathology showing granulomatous lesions is non-specific and cultures take anytime from 2-6 weeks. 

A lot of research has taken place in the direction of tests for diagnosis and treatment of pulmonary TB. However, there is still a large lacuna in research for diagnosis of genital TB. Molecular diagnostic methods seem to hold the key to the future of better and efficient diagnosis of genital TB. In order to obtain faster results, nucleic acid amplification tests are being increasingly used worldwide for the rapid diagnosis of TB. Cartridge based nucleic acid amplification testing (CB-NAAT) is a rapid molecular beacons based Xpert MTB/RIF assay technology and endorsed by RNTCP as a rapid molecular diagnostic tool for pulmonary TB. It provides results within 2 hours enabling same day diagnosis and prompt treatment initiation. Based on a  systematic review and meta-analysis to assess the accuracy of Xpert for the detection of extrapulmonary TB published in 2014, the World Health Organization now recommends Xpert over conventional tests for diagnosis of TB in lymph nodes and other tissues, and as the preferred initial test for diagnosis of TB meningitis.

Studies addressing the role of biomarkers and cytokines in diagnosis of TB have also been conducted.  Cytokines are small protein molecules that regulate immunological responses at cellular level. They stimulate and recruit wide range of cells involved in immunity and inflammation. Identification of a characteristic profile or panel of biomarkers could assist in improved diagnosis of FGTB also.

Women seeking treatment for infertility form a large chunk of the gynaecological patients. Availability of faster and cheaper tests would ensure better coverage of patients for diagnosis and treatment. Other than establishing an early diagnosis, it is important to also ensure treatment availability and adherence. In our clinical experience, women with established diagnosis of genital TB and its implications, face social stigma and isolation.

Genital TB amongst women still remains an under-addressed issue, especially in India. There is a pressing and urgent need for encouraging good quality, dedicated research in the direction of early diagnosis and treatment adherence of this condition. Determining a good and sensitive diagnostic test would go a long way in reducing the financial, physical and psychological impacts of this disease.

It  may be worth considering also to change from the old established tracks and make the strategies more inclusive, encouraging participation of lesser known names in the field including clinicians and laboratory researchers who sincerely feel for this cause.

Dr AG Radhika, Citizen News Service - CNS
(The author is a senior specialist in department of obstetrics and gynaecology, University College of Medical Sciences (UCMS) and Guru Teg Bahadur (GTB) Hospital, Delhi)
29 September 2014