Introduction. Urolithiasis and nephrotuberculosis, due to the similarity of the radiographic patterns, share the same differential diagnosis list. The study aimed to analyze the incidence of co-occurrence of nephrotuberculosis and urolithiasis and to determine the impact of urolithiasis on the clinical course of renal tuberculosis.
Material and methods. This open cohort retrospective study comprised 843 patients with renal tuberculosis and 245 patients with urolithiasis. 1088 medical records were analyzed to identify cases with co-occurrence of these two diseases and determine the clinical presentation of renal tuberculosis, urolithiasis, and the comorbid state. Also, patients with pulmonary tuberculosis (44), urogenital tuberculosis (17), and chronic nonspecific pyelonephritis (12) were tested for serum concentration of total calcium and phosphorus.
Results. Of 843 patients with renal tuberculosis, 39 (4.6%), had concomitant nephrolithiasis. The combination of urolithiasis with nephrotuberculosis manifested by more severe symptoms; these patients had a more than two-fold risk of tuberculosis recurrence. Except for the incidence of renal colic and dysuria, the clinical manifestations of urolithiasis and nephrotuberculosis did not differ statistically significantly. Prolonged infectious and inflammatory process in the kidneys resulted in an increase in the excretion of oxalates, which was more pronounced in patients with nonspecific pyelonephritis (p<0.05). A three-month course of antituberculosis chemotherapy resulted in a 36.2% increase in the excretion of oxalates in patients with urotuberculosis (p<0.05). Excretion of uric acid also significantly increased after a three-month intake of antituberculosis drugs.
Conclusion. In our study, the incidence of concomitant urolithiasis and urogenital tuberculosis was low (4.6%), but comorbidity significantly complicated the clinical course of the disease and worsened the prognosis of nephrotuberculosis. Antituberculosis polychemotherapy increases the risk for formation of urinary stones. Prevention of urolithiasis in patients with urogenital tuberculosis warrants further investigation.

Keywords: urogenital tuberculosis, nephrotuberculosis, urolithiasis, diagnosis, clinical presentation, features