# Atypical ulcerative cutaneous tuberculosis revealing disseminated mycobacterial infection: case report with diagnostic and therapeutic challenges

## TL;DR

A rare case of ulcerative cutaneous tuberculosis with disseminated infection is reported, emphasizing the need for early diagnosis and long-term treatment to prevent complications.

## Contribution

This case report highlights the diagnostic challenges of atypical ulcerative cutaneous tuberculosis and its potential for disseminated infection.

## Key findings

- Ulcerative cutaneous tuberculosis can present with disseminated mycobacterial infection without recent exposure.
- Standard anti-tuberculosis therapy showed partial improvement but not complete resolution after 8 months.
- Early recognition and prolonged treatment are essential to prevent long-term complications.

## Abstract

Cutaneous tuberculosis (CTB) is an unusual manifestation of extrapulmonary tuberculosis, accounting for only 1.0%–1.5% of cases. It presents with a wide range of clinical morphologies, often mimicking other dermatoses such as fungal infections, leprosy, or sarcoidosis. Among its different variants, the ulcerative form is particularly rare and clinically deceptive. Reporting rare presentation is important to raise awareness among physicians, as early recognition and prompt treatment are essential to prevent complications such as scarring, contractures, or malignant transformation.

We report the case of a 24-year-old Malian male admitted to the National Institute for Infectious Diseases Lazzaro Spallanzani. The patient presented with a 4-month history of ulcerative skin lesions on the chest, neck, and left leg, accompanied by systemic symptoms including asthenia, cachexia, and generalized lymphadenopathy. Imaging revealed extensive bilateral psoas abscesses, vertebral involvement consistent with spondylodiscitis, and signs of empyema necessitans. Polymerase chain reaction (PCR) testing of drained abscess fluid confirmed Mycobacterium tuberculosis complex. Skin biopsy histology and PCR further supported the diagnosis of CTB. The patient was treated with standard anti-tuberculosis therapy (isoniazid, rifampicin, ethambutol, pyrazinamide) alongside broad-spectrum antibiotics. After 30 days, partial improvement of skin lesions was observed, although complete resolution was not achieved after 8 months of follow-up.

This case highlights the diagnostic challenge and chronicity of CTB, particularly in the ulcerative presentation. The patient developed disseminated tuberculosis with cutaneous involvement without any recent travel or known tuberculosis exposure, and the probable etiology is latent reactivation. There should be a high index of suspicion for CTB in patients presenting with indolent, atypical skin lesions, particularly those from an endemic region. Early diagnosis and prolonged therapy are crucial to avoid long-term sequelae.