Candida parapsilosis vertebral Ooomyelitis: a rare complication of spinal cord stimulation

Spinal cord stimulation (SCS) has grown increasingly popular as a treatment option for pain refractory to pharmacotherapy and to conventional interventional pain management. Complications from permanent SCS implantation are most commonly due to hardware malfunction and electrode displacement, but also include serious deep tissue and spinal infections and abscess formation. We report a case of a 56 year-old male with history of intravenous drug abuse and chronic low back pain with a history of decompressive laminectomy, who presented with fever, chills, and worsening back pain three months after permanent spinal cord stimulator lead implantation. MRI of the lumbar spine revealed marked osseous destruction of the L1 and L2 vertebrae, and the contiguous intervertebral disc. CT-guided needle aspiration grew Candida parapsilosis. Subsequently, the patient underwent explantation of the neuromodulation system and was treated with high-dose fluconazole for six months. Follow-up MRI demonstrated stable osseous destruction and decreased enhancement. Invasive Candida parapsilosis osteomyelitis is an extremely rare disease. Vertebral osteomyelitis is most commonly secondary to hematogenous spread of a contagion, with direct inoculation from surgery or trauma as the next most common cause. Unlike Candida albicans which is an obligate human pathogen, Candida parapsilosis has been isolated from non-human sources including domestic animals and soil. In our case, intravenous drug abuse was the most likely cause of infection, although it is possible that inoculation occurred during surgical implantation. Co-morbidities associated with this infection include prior surgery, injection drug users, immune-compromised status, long-term central venous catheters, and broad-spectrum antibiotic use. Published rates of infection confirmed by culture after spinal cord stimulation approximate 2.5%. To our knowledge this is the first reported case of vertebral Candida parapsilosis osteomyelitis after permanent spinal cord stimulator implantation. In our case, pre-surgical screening for risk factors including intravenous drug abuse may have prevented this catastrophic infection.