A rare case of acute meningitis shortly after lumbar selective nerve root block: a case report.

A 57-year-old man underwent lumbar selective nerve root block (SNRB) for low back pain and lower radiating pain caused by left-sided L4 disc herniation. He presented to the emergency department with fever, headache and aggravated low back pain approximately 3 hours after the procedure. Infection was suspected; hence, blood tests, cerebrospinal fluid (CSF) tests, lumbar magnetic resonance imaging, and brain computed tomography were performed. Imaging findings were not suggestive of infection. The CSF was turbid and yellowish with pleiocytosis; however, the CSF culture was negative. Based on these findings, the patient was diagnosed with acute meningitis. Broad-spectrum antibiotics and steroid therapy were initiated considering the patient's age and general condition. From hospital day (HD) 2, fever and headache were reduced and disappeared completely by HD 5. At the last follow-up, 1 month after discharge, the patient had no symptoms. Acute meningitis is associated with a high mortality and neurologic deficits. Hence, timely tests, diagnosis, and treatment are critical for positive outcomes. Symptoms of meningitis following a nerve block generally occur within 24-48 hours after the procedure. This case is notable, as it involved a quicker and more sudden onset of symptoms; meningitis occurred only a few hours after lumbar selective nerve root block.