Abstract Body (Do not enter title and authors here): Introduction:
Austrian Syndrome is a rare, life-threatening triad of pneumonia, meningitis, and endocarditis caused by Streptococcus pneumoniae, typically in immunocompromised or alcoholic patients. Though it accounts for ~14% of S. pneumoniae endocarditis cases, purulent pericarditis is exceptionally rare. We present a case complicated by purulent pericarditis with tamponade, highlighting the need for early recognition and multidisciplinary care.

Case Description:
A 63-year-old unhoused woman with tobacco and fentanyl use was found unresponsive by her son and brought to the emergency department by EMS. She presented with acute hypoxic respiratory failure, altered mental status, and abdominal pain. Vitals: BP 172/96 mmHg, HR 132 bpm, and hypoxia on 3 L oxygen via nasal cannula. Exam showed Kussmaul respirations, jugular venous distention, and cool extremities. Labs showed leukocytosis, lactic acidosis, acute kidney injury, and elevated troponin suggesting demand ischemia. ECG demonstrated electrical alternans; chest CT revealed a moderate-to-large pericardial effusion. Point-of-care ultrasound confirmed tamponade with right ventricular diastolic and right atrial systolic collapse; pulsus paradoxus was 27 mmHg. Emergent pericardiocentesis drained 465 mL of turbid fluid; cultures of pericardial fluid and blood grew S. pneumoniae, confirming purulent pericarditis. Transthoracic echocardiogram showed fibrinous strands along the right ventricular septum, suggesting endocarditis. Bronchoscopy confirmed pneumonia, completing Austrian Syndrome. Follow-up chest CT showed loculated pericardial fluid with mediastinal abscess, requiring urgent surgical washout, window creation, and drain placement. Despite intensive antibiotics and multidisciplinary care, she developed septic shock, respiratory failure requiring intubation, and renal failure managed with CRRT, the patient died from multiorgan failure.

Discussion:
Purulent pneumococcal pericarditis with tamponade is a rare, often fatal complication of Austrian Syndrome. Early recognition via bedside imaging and clinical signs like pulsus paradoxus and electrical alternans is critical. Due to the purulent loculated effusion, surgical washout, pericardial window, and mediastinal drains are typically required, as medical therapy alone is inadequate. Mortality remains high, particularly with shock and multiorgan failure. Rapid diagnosis and coordinated care are essential in invasive pneumococcal infections.