Cauda equina syndrome secondary to lumbar spondylodiscitis caused by Streptococcus milleri

A 79-year-old Afro-Caribbean woman presented with a 5-month history of low back pain and a 2-month history of weakness of the lower limbs associated with cauda equina syndrome. A plain X-ray of the lumbar spine showed a collapse of the L4 body consistent with osteomyelitis. An MRI scan of the lumbar spine showed narrowing of the L3/4 disc space, destruction of the adjacent vertebral bodies and an epidural abscess. She was admitted to hospital and treated with a high dose of i.v. antibiotics followed by radical surgical excision of the lesion through a combined anterior and posterior approach with instrumentation. Tissue culture grew Streptococcus milleri. One week after surgery the patient developed septicaemia. A blood culture grew Pseudomonas aeruginosa, which was successfully treated with antibiotics. She eventually recovered bowel and bladder control and regained muscle power in the lower limbs. Streptococcus milleri is a rare causative organism in osteomyelitis, this being only the eighth reported case in the literature. Aggressive surgical treatment combined with a prolonged antibiotic regime is recommended to achieve a satisfactory result.