Neisseria sicca Endocarditis Complicated by Intracranial and Popliteal Aneurysms in a Patient with a Bicuspid Aortic Valve

We report a case of infective endocarditis due to Neisseria sicca complicated by intracranial and popliteal aneurysms and hepatic and splenic infarcts in a patient with a bicuspid aortic valve. No predisposing factor other than poor dental condition was found. The patient fully recovered after antibiotic therapy, aortic and mitral valve replacement, endovascular occlusion of the middle-cerebral artery aneurysm, and surgical treatment of the popliteal artery aneurysm. 1. Background The Neisseria genus includes a wide range of species, N. meningitidis and N. gonorrhoeae being the two most frequently involved in infections in humans. Other species, which are part of normal oropharyngeal flora, are often referred to as “nonpathogenic Neisseria” although they may be responsible for serious conditions such as endocarditis, meningitis, osteomyelitis, vertebral osteomyelitis, and pneumonia. We report the case of a patient with Neisseria sicca endocarditis, complicated with mycotic aneurysms of the middle cerebral and popliteal arteries. 2. Case Presentation A 41-year-old male patient with a known history of bicuspid aortic valve was admitted to hospital for persisting fever and flu-like syndrome. He had smoked 40 cigarettes a day for 10 years and denied any illicit drug use. Twenty days prior to admission, he had developed myalgia, anorexia, intermittent fever and fatigue. He had been evaluated by his general practitioner whose findings were unremarkable. One week later, laboratory test results were as follows: whole white blood cell count 16.7？G/L and C-reactive protein 336？mg/L. Urine culture was positive for E. coli (103？CFU/ml) and the patient was given amoxicillin/clavulanate. Because his symptoms did not abate he was admitted to hospital. On admission, temperature was 38.5°C, heart rate was 98？bpm, and blood pressure was 100/80？mmHg. Cardiac examination revealed a systolic murmur, maximal at the aortic area. Breath sounds were normal. The liver was moderately enlarged. There was no pedal edema. Neurological examination was unremarkable. Dental condition was poor. The WBC count was 19.4？G/L. Serum ALT and AST levels were 184？U/L and 216？U/L, respectively;？？γ-GT was 146？U/L; alkaline phosphatase was 133？U/L and C-reactive protein was 278？mg/L. Brain natriuretic peptide level was 217？pg/mL (0–100？pg/mL). Chest X-ray was normal. Electrocardiogram showed a sinus rhythm and a heart rate of 100？bpm. Transesophageal echocardiography showed a bicuspid aortic valve with a ？mm vegetation attached on the ventricular leaflet, associated with a grade 2 aortic