Diffuse Alveolar Hemorrhage as a First Presentation for Acute Mitral Regurgitation: Case Report.

Diffuse alveolar hemorrhage (DAH) is a medical emergency that is known to be caused by systemic vasculitis, autoimmune conditions, coagulation disorders, and toxins. While it can be caused by chronic mitral regurgitation (MR), it has a rare association with acute MR. We report the case of a patient presenting with DAH as the first sign of acute MR. A 58-year-old man with type 2 diabetes mellitus and no cardiac history except for hypertension presented with dyspnea and cough with pink-stained white sputum for two days. On examination, bilateral crepitations and a pansystolic murmur were noticed. N-terminal pro-B-type natriuretic peptide (NT-proBNP) was 165 ng/L, while high-resolution computed tomography (HRCT) showed diffuse bilateral ground-glass opacities with a crazy paving pattern. Transesophageal echocardiography (TEE) showed preserved left ventricular ejection fraction (>60%) and confirmed moderate-to-severe eccentric acute MR due to posterior leaflet prolapse with rupture of marginal chordae tendineae. Bronchoalveolar lavage (BAL) confirmed alveolar hemorrhage and established the diagnosis of DAH, which initially mimicked severe respiratory infection due to the presence of pink-stained sputum and bilateral infiltrates. Following stabilization, the patient was scheduled for mitral valve replacement. This case illustrates the importance of considering cardiac etiologies and performing early echocardiography in patients presenting with unexplained DAH, as these etiologies can mimic common causes of DAH.