Garg P, Garg M, Das BR, et al. - Researchers sought to ascertain the best method to diagnose tuberculosis in patients with fistula-in-ano. In addition, they conducted a systematic review to circumscribe the incidence and characteristics of tuberculosis fistula-in-ano. They conducted prospective analysis of patients with tuberculous fistula-in-ano who were treated between 2014 and 2018, and completed a systematic review of studies describing ≥ 3 patients with tuberculosis fistula-in-ano. Testing in 637 samples (410 patients) led to detection of tuberculosis in 49 samples (43 patients). Testing of 106 additional samples in patients with a high index of suspicion yielded positive results in 14 more patients. The analysis revealed that relative to histopathology, a polymerase chain reaction has a significantly higher tuberculosis detection rate. Among polymerase chain reaction, a higher detection rate was evident with pus vs tissue. They observed the association of tuberculosis with more complex and recurrent fistulas.