PNEUMOTHORAX EX VACUO AS INITIAL PRESENTATION OF ENDOBRONCHIAL TUBERCULOSIS BY MYCOBACTERIUM BOVIS
Critical Care Medicine
INTRODUCTION: Mycobacterium bovis infection in humans is an extremely rare entity. M. tuberculosis and M. bovis are clinically and radiographically indistinguishable, hence, genotype-based identification is required. Management and outcomes of M. bovis infection are not well described. We present the first case of endobronchial tuberculosis secondary to M. bovis in an immunocompetent host. DESCRIPTION: A 19 year old woman without past medical history presented to the emergency department for sudden onset left-side chest pain and dry cough. A preoccupational evaluation noted a positive tuberculin skin test with normal chest-xray. Physical exam significant for absent breathing sounds in the left upper lung. Laboratory tests include leukocyte count of 9.8 bil/L, hemoglobin of 11 gr/ dL and procalcitonin of 0.02ng/mL. Computed Tomography of the chest showed complete left upper lobe collapse with obstruction of the left main bronchial lumen and left side pneumothorax ex-vacuo. Emergency bronchoscopy revealed a partially obstructed left mainstem bronchus with erythematous, friable mucosa and granular white tissue. Balloon dilation was performed successfully and samples from bronchoalveolar lavage (BAL) and biopsy of the granular tissue were obtained. Acid Fast Bacilli in Sputum and Quantiferon tests resulted negative, but Protein Chain Reaction analysis of BAL came positive for Mycobacterium tuberculosis and the patient was started on rifampicin, isoniazid, pyrazinamide and ethambutol (RIPE) therapy. BAL culture grew Mycobacterium bovis identified by pyrazinamide monoresistance, confirmed by the Michigan Department of Health and Human Services. At 6 months follow up, the patient complained of a lingering cough, wheezing and shortness of breath. Bronchoscopy control showed recurrence of initial lesions that required balloon dilation. Cultures obtained grew Aspergillus spp and the patient was started on voriconazole. DISCUSSION: To our knowledge, ours is the first case report of M. bovis presenting with endobronchial obstruction without parenchymal compromise in an otherwise healthy patient. We aim to highlight the diagnostic challenges of this rare case: extremely low incidence of the disease, nonspecific presentation, absent risk factors and high rate of short term complications despite treatment.
Gomez Rojas OR, Weatherhead M, Hicks M, Dado C, Adam A. Pneumothorax ex vacuo as initial presentation of endobronchial tuberculosis by Mycobaterium bovis. Crit Care Med. 2022 Jan;50(1):358. doi: 10.1097/01.ccm.0000809240.98716.2c.