A70-48 When Prevention Fails: Pulmonary Tuberculous Abscess in a Malnourished Unvaccinated Infant

Abstract Introduction Tuberculosis (TB) remains a major global health concern, accounting for approximately 11% of all cases in children worldwide. Pulmonary tuberculous abscess is a rare manifestation, representing less than 0.1% of cases, particularly uncommon in infants. Risk factors such as lack of BCG vaccination and malnutrition significantly increase susceptibility to severe and atypical forms of TB. Case Presentation A 15-month-old boy presented with a one-week history of productive cough and rhinorrhea, and three days of fever and respiratory distress. On admission, he appeared chronically malnourished (weight 8.4 kg, -1.86 SD; length 71 cm, -3.22 SD; weight/length -0.35 SD). Chest X-ray showed a right basal opacity with internal lucencies. Empirical broad-spectrum antibiotics were started, but fever and tachypnea persisted. On hospital day five, chest CT revealed a 4 × 4.2 cm cavitary intraparenchymal lesion with air-fluid levels and necrosis in the right lower lobe, middle-lobe consolidation, ipsilateral pleural effusion, and a mediastinal lymph node mass. A closed thoracotomy drained 600 mL of purulent fluid. Pleural fluid PCR was positive for Mycobacterium tuberculosis, and the Mantoux test showed 30 mm induration. Anti-tuberculous therapy with four drug regimen was initiated with gradual improvement. This patient was born at home to a 25-year-old multigravida mother and had not received the BCG vaccine. Maternal evaluation revealed a 25 mm Mantoux reaction and cavitary lesions on chest imaging with positive sputum PCR for M. tuberculosis. Discussion Pulmonary tuberculous abscesses are rarely reported in children, often mimicking necrotizing bacterial pneumonia and leading to delayed diagnosis. Imaging typically reveals cavitary lesions with air-fluid levels and parenchymal necrosis. Malnutrition compromises cell-mediated immunity, predisposing to extensive necrotizing disease and delayed recovery. Previous reports, such as Aggarwal et al., highlight that M. tuberculosis should be considered even in primary lung abscesses unresponsive to antibiotics. Early identification through molecular testing and initiation of four-drug therapy are critical for recovery, particularly in endemic regions. Conclusion Pulmonary tuberculous abscesses are rarely reported in children. Malnutrition, absence of BCG vaccination, and close exposure to an untreated source case increase vulnerability to severe forms of tuberculosis. This case highlights the devastating consequences of missed vaccination and delayed detection of household tuberculosis. References: 1. WHO Global Tuberculosis Report 2023. 2. Aggarwal A, et al. Afr J Intern Med. 2019;7(5):001-003. 3. ATS/CDC/IDSA Clinical Practice Guidelines: Diagnosis of Tuberculosis in Adults and Children. Clin Infect Dis. 2017;64(2):111-115. This abstract is funded by: None