Identification of mycobacterium tuberculosis in genitourinary tract using in sity hybridization polymerase chain reaction

Tuberculosis infection in genitourinary tract is not uncommon. The outcome for the patient could be improved if fast, simple, and reliable tests could be developed. Herein, we have established the technique of in situ hybridization PCR (ISH-PCR) examination of resected or biopsied tissues from genitourinary tract for rapid detection of Mycobacterium tuberculosis existence. Totally 35 cases were enrolled in this study. Among them, 5 patients were diagnosed to be TB infection definitely by positive Mycobacterial culture or histological finding. The five patients consisted of 2 of TB kidney, 1 of TB bladder, 1 of TB prostate (BCG-intravesical therapy induced), and 1 of TB epididymitis. The other 30 patients were clinically suspicious of TB infection with 3 of retroperitoneal abscess, 6 of epididymal abscess, 4 of xanthogranulomatous pyelonephritis (XGPN), 5 of renal stone associated with pyelonephritis, 3 of testicular granuloma, 6 of chronic cystitis, 1 of suspected TB cystitis, 1 of chronic ureteritis, and 1 of retroperitoneal fibrosis. Representative tissue blocks were processed according to standard procedure of PCR-ISH. The results were read under microscope. The total detection rate of ISH-PCR for TB infection in these patients was 46% (16/35). The positive diagnosis rate of PCR-ISH in clinically diagnosed five TB patients was 100%. In clinically suspected 30 patients, 11 cases (37%) demonstrated positive TB stain under PCR-ISH procedure. Among the 11 patients, 4 were of epididymal abscess (4/6, 67%), 2 were of retroperitoneal abscess (2/3, 67%), 2 were of XGPN (2/4, 50%), 2 were renal stone with pyelonephritis (2/5, 40%), and 1 was testicular granuloma (1/3, 33%). The ISH-PCR can prompt us in the early diagnosis and identify obscure disease entities of M. tuberculosis infection in genitourinary tract and improve the treatment outcome of patients.