Outside The Box But All Squeezed In: A 23-year-old Man With Progressive Dyspnea After Overseas Travel

Case Presentation: A 23-year-old previously healthy man presented with progressive dyspnea. Physical examination revealed jugular venous distension and lower extremity edema. Laboratory testing demonstrated elevated B-type natriuretic peptide (193 pg/mL) and normal high sensitivity troponin. Echocardiogram revealed small pericardial effusion, respiratory variation in diastolic flow across the mitral valve, diastolic septal bounce, and annulus reversus ( Figure ). The differential diagnosis for constrictive pericarditis was broadly considered in the context of a recent febrile illness and frequent travel to Hawaii and Vietnam; we included infectious, autoimmune, and malignant etiologies. Cardiac magnetic resonance imaging revealed thickening and diffuse enhancement in the pericardium as well as ventricular interdependence. Chest CT identified hilar and anterior mediastinal lymphadenopathy. Laboratory testing was positive for QuantiFERON gold and negative for COVID-19, HIV, and ANA. Transbronchial biopsy demonstrated non-necrotizing granulomas with negative acid-fast bacilli smear, culture, and polymerase chain reaction for mycobacterial DNA. Re-examination identified a red-brown plaque on the patient’s thigh; biopsy showed granulomatous inflammation and rod-shaped organism with positive FITE staining. A presumed unifying diagnosis was made of extrapulmonary tuberculosis (TB) complicated by constrictive pericarditis. Discussion: Despite being a primarily pulmonary disease, systemic involvement can occur with TB with the heart being one of the most common extrapulmonary sites. This case highlights 1) the utility of extra-cardiac diagnostic testing (e.g., dermatologic biopsy) in the diagnosis of constrictive pericarditis, and 2) the diagnostic challenge associated with extrapulmonary TB, particularly paucibacillary disease that requires a detailed social history with “out-of-the-box” thinking.