A Fatal Case of Rat-Bite Fever A Mechanical Circulatory Support Conundrum

BACKGROUND: Rat bite fever is a rare infection that can cause severe complications such as infective endocarditis with a mortality rate of 13% if left untreated. CASE SUMMARY: We present the first reported fatal case of rat bite fever requiring mechanical circulatory support in a 48-year-old woman who presented with diarrhea, syncope, and lower back pain. Echocardiogram revealed tricuspid valve endocarditis, a large aortic root abscess, and a moderate-to-large membranous ventricular septal defect. After empiric antibiotics and extensive cardiac surgery, the patient remained in refractory cardiogenic shock requiring venoarterial extracorporeal membrane oxygenation support. Despite maximal supportive measures, the patient ultimately succumbed to her critical illness. DISCUSSION: Rat bite fever often presents with nonspecific symptoms that can delay presentation to medical attention, diagnosis, and targeted treatment. Most cases are caused by Streptobacillus moniliformis and result from rodent bites or exposure to contaminated food or water. Diagnosis can be challenging as the organism is fastidious, difficult to grow, and has limited diagnostic tests available for early detection. TAKE-HOME MESSAGES: Rat bite fever is a potentially fatal infection that presents with nonspecific symptoms. Late presentation can result in catastrophic complications and high mortality.