Forget me not': Urine cytology in a male with hematuria
| C A S E HIS TORY• 41-year-old male.• Presented with painless hematuria with occasional passage of clots over the last 2 months. Enigma Portal A Urine culture. B Acid fast bacilli positivity. C Polymerase chain reaction. D All of the above. 4. Acid fast bacilli can be demonstrated on urine cytology in what proportion of these cases? A 80%-100%. B 25%-42%. C 50%-70%. D 1%. Tuberculosis (TB) of the urinary tract, although rare in the west, is still a common disease in developing countries of the world. Urinary tract TB includes infection of the real pelvis, ureters, urinary bladder and/or urethra and invariably occurs as a complication of renal TB. Owing to the variable clinical presentations of the disease, establishing a diagnosis is often challenging and a high index of suspicion is required. Early diagnosis of the disease is the key to better patient outcome as progression of the disease leads to irreversible damage to the affected organs. Urine cytology is an indispensable and the most inexpensive method for establishing a diagnosis of a wide variety of non-neoplastic as well as neoplastic diseases involving the urinary tract. However, the reported sensitivity of urine cytology for diagnosing TB is variable with scattered reports depicting the cytologic findings. 3 Cytologic diagnosis of TB on urine smears requires presence of epithelioid cell granulomas and scattered multinucleated Langhans' type giant cells in an often dirty background with variable numbers of inflammatory cells including neutrophils and lymphocytes along with demonstration of acid fast bacilli (AFB) on Ziehl-Neelson (ZN) staining. However, since the presence of epithelioid cell granulomas in urine is uncommon, the less experienced pathologists fail to identify these on urine smears. Additionally, the frequency of AFB positivity in urine smears is very low. 4 Besides urine cytology, a number of other tests are also available to establish a diagnosis of urinary tract TB, including urine culture (solid as well as liquid culture methods), urine polymerase chain reaction for Mycobacterium tuberculosis, real-time nucleic acid amplification technology, interferon-gamma release assay and antigen detection tests. 5 The present case demonstrates the typical cytomorphologic features of urinary TB and highlights the diagnostic utility of urine cytology and ZN staining in establishing the diagnosis, especially in resourcepoor settings.