GENITAL TUBERCULOSIS

The incidence of genital tuberculosis varies widely with the social status of the patient and her environment. The incidence is about 1 per cent amongst the gynecological patients attending the outpatient department in the developing countries. Incidence is high (5–10%) amongst the patients with infertility. With the prevalence of HIV infection incidence of genital tuberculosis is rising. About 10 per cent of women with pelvic tuberculosis, have urinary tract tuberculosis.

The causative organism is Mycobacterium tuberculosis of human type. Very rarely the bovine type may affect the vulva. Genital tuberculosis is almost always secondary to primary infection elsewhere in the extragenital sites such as lungs (50%), lymph nodes, urinary tract, bones and joints. The fallopian tubes are invariably the primary sites of pelvic tuberculosis from where secondary spread occurs to other genital organs.

From any of the primary sites, the pelvic organs are involved by hematogenous spread in about 90 per cent cases. If the post-primary hematogenous spread coincides with the growth spurt of the pelvic vessels, the genital organs, the tubes in particular, are likely to be affected. Thus, the pelvic organs are infected during puberty. If the spread precedes the growth phase, the genital organs are spared. The infection remains dormant for a variable period of time (4–6 years) until clinical manifestations appear

The commonest site of affection is the fallopian tubes (100%). Both the tubes arection is in the submucosal layer (interstitial salpingitis) of the ampullary part of the tube. The infection may spread medially along the wall causing destruction of the muscles which are replaced by fibrous tissue. The walls get thickened, become calcified or even ossified. The thickening may at time become segmented. The infection may spread inwards; the mucosa gets swollen and destroyed. The fimbria are everted and the abdominal ostium usually remains patent. The elongated and distended distal tube with the patent abdominal ostium gives the appearance of “tobacco-pouch”. Occlusion of the ostium may however occur due to adhesions.The tubercles burst pouring the caseous material inside the lumen producing tubercular pyosalpinx, which may adhere to the ovaries and the surrounding structures. Often the infection spreads outwards producing perisalpingitis with exudation, causing dense adhesions with the surrounding structures— tubercular tubo-ovarian mass. Rarely, military tubercles may be found on the serosal surface of the tubes, uterus, peritoneum or intestines. These are often associated with tubercular peritonitis

Microscopic picture of the lesion is very characteristic irrespective of the organ involved. Typical granuloma consists of infiltration of multinucleated giant cells (Langhans), chronic inflammatory cells and epithelioid cells, surrounding a central area of caseation necrosis. Caseation may not be a constant feature.

The infection is restricted mostly (80%) to childbearing period (20–40 years). There may be past history of tubercular affection of the lungs or lymph glands. Genital tuberculosis occurs in 10–20 per cent of patients who have pulmonary tuberculosis in adolescence. A family history of contact may be available. Onset is mostly insidious. A flare up of the infection may occur acutely either spontaneously or following diagnostic endometrial curettage or hysterosalpingography.