# Isolated anal tuberculosis presenting as an anal fistula in an immunocompetent child

## TL;DR

A 13-year-old child with an anal fistula was diagnosed with rare anal tuberculosis and successfully treated with medication.

## Contribution

This case highlights the importance of considering tuberculosis in diagnosing anal fistulas, even in immunocompetent individuals.

## Key findings

- Anal tuberculosis was confirmed through histopathology and GeneXpert testing in a child with an anal fistula.
- The patient showed complete recovery after six months of anti-tubercular treatment with no recurrence after eight months.
- Tuberculosis should be considered in the differential diagnosis of anal fistulas despite its rarity in this location.

## Abstract

Extra‐pulmonary tuberculosis accounts for less than 15% of all tuberculosis cases, while intestinal tuberculosis accounts for less than 1% of extra‐pulmonary forms of the disease. Abdominal organ involvement is more common, but extension to the ano‐perineal region is extremely rare. We report a case of a 13‐year‐old child with an anal fistula without any other signs suggestive of tuberculosis. Diagnosis was confirmed by histopathological examination of the excised fistula and a positive GeneXpert test on fistula material. The initial work‐up ruled out Crohn's disease and other localizations secondary to tuberculosis, so the patient was put on anti‐tubercular drugs. Six months after the start of treatment, the lesion had completely disappeared, and no recurrence occurred after 8 months of follow‐up. Tuberculosis should generally be considered in the differential diagnosis of anal and perianal fistula despite the rarity of this location. In most cases, treatment is primarily medical, with surgical intervention reserved for complications such as abscesses or persistent fistulas.