CONSTRICTIVE PURULENT PERICARDITIS DUE TO STREPTOCOCCUS PNEUMONIAE: CASE REPORT

Pericarditis is an inflammation of the pericardium that can be acute or chronic. The most common causes are viral and autoimmune, followed by bacterial infections, neoplasms, trauma and others. Clinical manifestations vary according to severity and etiology. We present a case of acute purulent pericarditis due to Streptococcus pneumoniae. A 54-year-old male, previously healthy, sought care on 06/12/25 with precordial pain and a syncopal episode after mild exertion. On examination, he was tachycardic, with no other abnormalities. ECG showed ST-segment elevation in V2 to V4. Coronary angiography revealed no obstructive lesions. Laboratory tests: leukocytosis (19,500), elevated troponin, normal renal function. Initial transthoracic echocardiogram (TTE) was unremarkable. On 06/14/25, he evolved with clinical and laboratory worsening, increased tachycardia and hypotension. A sepsis protocol was initiated, cultures were collected, and ceftriaxone plus azithromycin were started. TTE showed a moderate pericardial effusion. The patient underwent urgent pericardial drainage, with 450 mL of purulent fluid removed, which was sent for culture; vancomycin was added. Chest CT showed bilateral pleural effusion and bibasilar consolidations, and laboratory tests continued to show elevated inflammatory markers associated with respiratory worsening. Left thoracostomy was performed, with drainage of 400 mL of turbid fluid. Culture of pericardial fluid isolated Streptococcus pneumoniae; guided therapy with ceftriaxone was maintained, initially planned for 4 weeks. Analysis of pleural fluid revealed an exudate, with negative cultures. The patient experienced gradual clinical and laboratory improvement; after 3 weeks of treatment, TTE and cardiac MRI still showed pericardial thickening and a small loculated collection with purulent aspect. The cardiac surgery team decided on expectant management given the favorable evolution, and antibiotic therapy was extended. This case illustrates the diagnostic complexity of pericarditis, which may mimic myocardial infarction or pulmonary diseases. Diagnosis requires integration of clinical evaluation, laboratory tests and imaging (TTE and cardiac MRI). Treatment depends on etiology, ranging from anti-inflammatory drugs and colchicine to antibiotics and surgery. Culture of pericardial fluid was essential to guide management, highlighting the importance of etiologic diagnosis for a personalized and effective approach.