Bochdalek diaphragmatic hernia masquerading as pneumonia--a rare cause of non-traumatic hemothorax

Hemothorax is defined as collection of blood in the pleural cavity. Massive hemothorax may result in severe respiratory distress. We present an extremely rare cause of non-traumatic hemothorax in a 3 1/2-year-old girl by Bochdalek diaphragmatic hernia (BDH), and that was initially misdiagnosed as pneumonia with massive pleural effusion. Hemothorax masks the clinical and X-ray findings of BDH that makes the diagnosis even more difficult. Delayed or incorrect diagnosis of BDH complicated with respiratory distress leads to the wrong decision-making and the subsequent management, which may result in significant morbidity and mortality. Accordingly, emergency physicians need to be aware of this extremely rare etiology when evaluating pediatric hemothorax in a busy emergency department.