A49-11 A Killer on the Move: Hypervirulent Klebsiella Pneumonia Causing Widespread Septic Emboli

Introduction Septic pulmonary emboli is a rare, life-threatening complication arising from infectious sources that seed embolic material throughout the pulmonary vasculature. Klebsiella pneumoniae is an uncommon etiology, typically presenting as severe lobar pneumonia, urinary tract infection, or liver abscess. Emerging hypervirulent strains have been reported to cause invasive syndromes with metastatic spread. We present an unusual case of K.pneumoniae bacteremia and multifocal pneumonia complicated by diffuse septic emboli, pericardial effusion, ruptured intraparenchymal abscess, and multifocal cerebral infarctions demonstrating an unusually aggressive disease course. Case Description A 59-year-old woman with diet-controlled type 2 diabetes and chronic back pain presented after a mechanical fall with progressive dyspnea and productive cough. She was intubated for acute hypoxic respiratory failure. CT chest revealed multiple bilateral pulmonary masses concerning for malignancy versus septic emboli, a small pneumomediastinum, and a moderate pericardial effusion. Blood cultures grew K.pneumoniae, confirming bacteremia with multifocal pneumonia. MRI brain demonstrated multiple acute infarcts in the right frontal, parietal, and occipital lobes consistent with septic emboli. Transthoracic echocardiography showed no valvular vegetations and improvement in pericardial effusion without hemodynamic compromise. Despite broad-spectrum antibiotics and supportive management, she developed a left pyopneumothorax with a persistent air leak. Thoracic surgery performed video-assisted thoracoscopic surgery with decortication, pleurodesis, and evacuation of a ruptured intraparenchymal abscess. Operative findings demonstrated extensive intrapleural purulence and friable adhesions between visceral and parietal pleura. The patient was extubated but required reintubation due to worsening hypoxemia. Subsequently, she developed left lower extremity hypoperfusion requiring anticoagulation. Despite maximal medical and surgical interventions, her respiratory status continued to decline. After multidisciplinary discussion and goals-of-care conversations with the family, life-sustaining measures were withdrawn in accordance with patient and family wishes. Discussion This case highlights a fulminant, disseminated K.pneumoniae infection manifesting as septic emboli, multifocal pneumonia, pericardial effusion, and cerebral embolization without a primary hepatic or endocardial source. While classic K.pneumoniae typically causes localized necrotizing consolidation, this case demonstrated hematogenous dissemination mimicking metastatic malignancy. Diabetes and metabolic derangements likely contributed to immune dysfunction and bacterial invasion, consistent with the emerging hypervirulent Klebsiella phenotype. Early recognition, aggressive antimicrobial therapy, and coordinated multidisciplinary care are critical to improving outcomes in such rapidly progressive infections.