An Unusual Case of Post-Operative Spondylitis Caused byMycobacterium Intracellularein an Immunosuppressed Patient

Abstract

A 75-year-old female with low back pain and paraparesis after a fall presented to our hospital for evaluation. On the neurologic examination, motor function in both legs were decreased to a grade of 3/5 and severe low back pain was associated with localized tenderness over the lumbar region. She had received medications of steroids for rheumatoid arthritis for 2 years. No previous surgeries had been performed except for removal of fibromyoma in both wrists. Laboratory testing showed that the erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and white cell count were normal. The radiologic examination revealed osteoporotic compression fractures of L1, L3 and L4 bodies and an epidural hematoma compressing the spinal cord along the dura mater of the L2 to L4 spine ( Fig. 1, 2). She underwent urgent decompressive laminectomies of L2, L3 and L4 and removal of the dark-red epidural mass with multiple tissue cultures. She was treated with cefazolin for prevention of postoperative infection and the steroids for rheumatoid arthritis were discontinued. She was symptom-free after surgery and ambulated well with braces. The histopathologic results showed that the stains of the biopsy specimens were all negative for bacteria, fungi and acid-fast bacilli (AFB). Ten days post-operatively, even though the ESR and CRP were elevated to 50 mm/hr INTRODUCTION Post-operative spondylitis is an undesirable complication of spinal surgery. Staphylococcus aureus has been reported as the most frequently isolated organism in patients with post-operative spondylitis 8) . Recently, infections with methicillin-resistant S. aureus (MRSA) and gram-negative organisms have increased dramatically 14) . However, there are only few reports of post-operative spondylitis by non-tuberculous mycobacterium (NTM). In patients with spondylitis, the degree of immunosuppression is as high as 51.5% 11). However, there are no consensus treatment guidelines for the treatment of spondylitis 11) . In a case, due to multi-drug resistance, prolonged anti-mycobacterial medications in combination with radical debridement with or without fusion are essential for spondylitis by NTM 5). We report an unusual case of post-operative spondylitis by Mycobacterium intracellulare in a immunosuppressed patient. Department of Neurosurgery, School of Medicine, Pusan National University, Yangsan Hospital, Yangsan, KoreaThere are few reported cases of post-operative spondylitis caused by Mycobacterium intracellulare. A 75-year-old female presented to our hospital with low back pain and paraparesis after a fall. The radiologic examination revealed compression fractures of L1, L3 and L4 and an epidural hematoma compressing the spinal cord. The dark-red epidural hematoma was urgently evacuated. Four weeks post-operatively, neurologic deficits recurred with fever. On magnetic resonance image, an epidural abscess and osteomyelitis were detected in the previous operative site. Five weeks post-operatively, revision was performed with multiple biopsies. The specimen were posi...