Pseudotumoral form of primary progressive tuberculosis: a diagnosis to be considered

Area of Science:

• Pediatrics
• Infectious Diseases
• Radiology

Background:

• Primary progressive tuberculosis (TB) diagnosis is challenging due to diverse clinical presentations and paucibacillary forms, often delaying treatment.
• The nodal pseudotumoral form of TB is a rare manifestation, particularly in immunocompetent children, and can mimic neoplastic conditions.

Observation:

• A 10-year-old child presented with chest pain and progressive upper mediastinal widening, with calcifications detected by CT scan but not X-ray.
• Mediastinoscopy biopsy suggested tuberculosis, but mycobacterial cultures, direct examination, and PCR failed to identify the etiologic agent.
• Tuberculin conversion occurred during follow-up, coinciding with lesion resolution after anti-TB therapy (isoniazid, rifampicin, pyrazinamide).

Findings:

• Diagnosis of paucibacillary tuberculosis was confirmed indirectly through clinical response and tuberculin conversion, despite negative microbiological tests.
• Computerized tomography (CT) imaging revealed calcifications missed by initial X-rays, aiding in diagnosis.
• The case highlights the diagnostic challenges of atypical tuberculosis presentations in pediatric patients.

Implications:

• The nodal pseudotumoral form of tuberculosis should be considered in the differential diagnosis of anterosuperior mediastinal masses in children.
• Advanced imaging like CT is vital for detecting subtle signs of tuberculosis in pediatric mediastinal masses.
• This case underscores the importance of considering tuberculosis even when initial microbiological investigations are inconclusive, especially in endemic areas.