Case Presentation: A 57-year-old female with a medical history of uncontrolled diabetes with a hemoglobin A1C of 14, hypertension, and a previous right-sided stroke presented to the emergency department with a four-day history of nausea, vomiting, watery diarrhea, fever and chills. On presentation, the patient was hemodynamic stable with no fevers. Physical examination revealed no significant findings. Laboratory tests showed leukocytosis with an initial white blood cell count of 12.6, elevated creatinine levels of 1.26 mg/dl, and pronounced hyperglycemia with blood glucose levels in the 600s mg/dL. and a significant troponin increase. An EKG showed sinus tachycardia with Q waves in the inferior leads, though it was nondiagnostic for acute ischemia. Chest X-ray and abdominal-pelvic CT showed no abnormalities. To explore potential infectious origins, blood and urine cultures were collected. The patient was admitted and received intravenous fluids and subcutaneous insulin to address acute kidney injury and hyperglycemia. Additionally, aspirin and heparin drip therapy were administered to manage the elevated troponin levels. Empirical antibiotics, including IV Vancomycin and Piperacillin-Tazobactam, were started for treatment for sepsis. Considering the possibility of endocarditis, a transthoracic echocardiogram was done which showed no vegetation. After three days, blood cultures identified Lactobacillus spp, leading to adjustments in antibiotic therapy with IV ampicillin replacing prior agents. Due to the elevated risk of endocarditis associated with Lactobacillus bacteremia, a transesophageal echocardiography (TEE) was conducted, revealing a 0.4 cm by 0.5 cm mass on the thickened aortic valve, indicative of vegetation attached to the aortic side of the non-coronary cusp. Further patient history revealed recently increased consumption of grapes and strawberries, where Lactobacillus can colonize. Otherwise, no additional risk factors for Lactobacillus endocarditis, such as probiotic use, recent dental work, or immunodeficiency, were identified. Given the valve size, the patient was not a candidate for valve surgery and was treated with IV antibiotics. She completed a six-week course of IV penicillin and gentamicin, resulting in negative final blood cultures and clinical improvement. Post-discharge, the CT coronary angiography revealed a 0.5 cm mass on the aortic side of the non-coronary cusp of the aortic valve, which remained stable in size.
Discussion: Lactobacillus jensenii is a gram-positive, non-spore forming, rod-shaped, anaerobic bacteria. Fifty cases of Lactobacillus endocarditis have been reported in the literature, estimated to be responsible for approximately 0.05–0.4% of all cases of infectious endocarditis. and 11 cases of L. jensenii, including our case, have been described thus far. When endocarditis is suspected, the use of transesophageal echocardiography is recommended. Lactobacilli exhibit high sensitivity to penicillin G and synthetic penicillins, but they typically demonstrate resistance to vancomycin. This is significant as vancomycin is a key component in most initial sepsis treatments, as in our case.
Conclusions: Lactobacillus, a gram-positive rod-shaped bacteria, is commonly nonpathogenic in the oral cavity, gut, and female genital tract. Despite its rarity, causing less than 50 reported cases of infective endocarditis globally, we present a unique case of aortic valve endocarditis secondary to Lactobacillus jensenii.