Acute Pericarditis as an Initial Presentation of Neoplastic Disease: A Case Report.

Acute pericarditis is the most common pericardial disease, presenting with varied manifestations and potentially indicative of systemic disease. A 56-year-old male with a history of hypertension, dyslipidemia, type 2 diabetes, and a former smoker presented with chest pain relieved by leaning forward, fever, elevated inflammatory markers, and electrocardiographic changes consistent with acute pericarditis. Initial treatment with acetylsalicylic acid and colchicine resulted in a favorable clinical response with improvement in inflammatory markers. However, symptoms later worsened, accompanied by night sweats and weight loss. Imaging revealed a nonspecific pulmonary lesion in the right upper lobe and consolidation in the left lower lobe with associated pleural effusion. Pleural fluid analysis indicated an exudate, predominated by mononuclear cells, with negative cytology. A guided biopsy confirmed lung adenocarcinoma. This case underscores the importance of a holistic approach to acute pericarditis, with an emphasis on etiological investigation in atypical presentations.