Lumbar vertebral osteomyelitis and psoas abscess caused by Actinomyces israelii after an operation under general anesthesia in a patient with end-stage renal disease: a case report

BACKGROUND: Actinomycosis is a chronic, slowly progressive infection caused by the Actinomyces species. Lumbar vertebral involvement of Actinomyces israelii is extremely rare; this is the first case report of lumbar vertebral osteomyelitis and psoas abscess caused by Actinomyces israelii after an operation under general anesthesia. CASE PRESENTATION: A 66-year-old Japanese man with end-stage renal disease was admitted to our hospital for an operation for cervical canal stenosis. After the operation under general anesthesia, during which tracheal intubation and nasogastric tube insertion were performed, he developed low back pain. During a second hospitalization, computed tomography revealed osteolysis of the lumbar endplates of L2 and L3, swelling of the intervertebral disk of L2/L3, and swelling of the left psoas major muscle. Percutaneous drainage of the intervertebral disc was performed, and the culture of the aspirate grew Actinomyces israelii. Based on the susceptibility, ampicillin was administered but his condition did not improve. We changed the antibiotics to ampicillin-sulbactam for coverage of unidentified oral commensals, and his symptoms and signs finally improved. CONCLUSION: Our patient’s long-term end-stage renal disease had made the oral and gastrointestinal mucosal barriers very fragile. Under these conditions, even mildly invasive procedures such as tracheal intubation and nasogastric tube insertion could be the cause of infectious complication by oral commensals, including Actinomyces.