A Case Report on the Successful Treatment of Streptococcus pneumoniae-Induced Infectious Abdominal Aortic Aneurysm Initially Presenting with Meningitis

Infectious abdominal aortic aneurysms often present with abdominal and lower back pain, but prolonged fever may be the only symptom. Infectious abdominal aortic aneurysms initially presenting with meningitis are extremely rare; there are no reports of their successful treatment. Cases with Streptococcus pneumoniae as the causative bacteria are even rarer with a higher mortality rate than those caused by other bacteria. We present the case of a 65-year-old man with lower limb weakness and back pain. Examination revealed fever and neck stiffness. Cerebrospinal fluid showed leukocytosis and low glucose levels. The patient was diagnosed with meningitis and bacteremia caused by Streptococcus pneumoniae and treated with antibiotics. Fever, inflammatory response, and neurologic findings showed improvement. However, abdominal computed tomography revealed an aneurysm not present on admission. Antibiotics were continued, and a rifampicin soaked artificial vascular graft was implanted. Tissue cultures showed no bacteria, and histological findings indicated inflammation with high leukocyte levels. There were no postoperative complications or neurologic abnormalities. Physical examination, blood tests, and computed tomography confirmed there was no relapse over the following 13 months. This is the first reported case of survival of a patient with an infectious abdominal aortic aneurysm initially presenting with meningitis caused by Streptococcus pneumoniae.