Hydropneumothorax masking a dual pathological challenge: Ruptured pulmonary hydatid cyst co-existing with active tuberculosis

Introduction: The co-infection of pulmonary hydatid cyst (PHC) and tuberculosis (TB) represents a major diagnostic challenge in endemic regions. This association can be complex to identify when acute signs of a complication mask an underlying chronic process.
Case report: We report the case of a 16-year-old patient admitted for the assessment of an acute hydropneumothorax, occurring after a two-month history of chronic cough, night sweats, and constitutional symptoms. While initial pleural investigations—including biopsy and pleural fluid GeneXpert—showed no evidence of a bacillary process at the serosal level, the systematic search for scolex in the pleural fluid and the results of bronchial aspirates allowed for the final diagnosis to be established. The identification of scolex in the pleural fluid confirmed the cyst rupture, while systematic bronchial aspirates revealed positive GeneXpert and Koch's bacillus (BK) results, confirming a concurrent active pulmonary tuberculosis, despite negative bronchial scolex results.
Conclusion: This case highlights the crucial importance of direct scolex identification and systematic bronchoscopy with aspirates to unmask an occult parenchymal pathology during an acute pleural complication, especially when serological and pleural biopsy results are non-contributory.