Aspergillus terreus spondylodiscitis following an abdominal stab wound: a case report

Aspergillus terreus, a saprophytic fungus, is recognized as an emerging pathogen in various infections in humans. However, bone and joint involvement is uncommon. To the best of our knowledge, only seven cases of spondylodiscitis caused by Aspergillus terreus have been reported previously in humans. We report a case of a patient with Aspergillus terreus spondylodiscitis following an abdominal stab wound.

A 74-year-old Japanese man with no particular medical history fell from a ladder and sustained a left abdominal stab wound from an L-shaped metal peg. Computed tomography showed the trace of the L-shaped metal peg from the left abdomen to the left rib and left kidney. The scan also showed an anterolateral bone avulsion of the left side of the T12 vertebral body, as well as fractures of the L1 left transverse process and the left 10th-12th ribs. He was hospitalized and treated with conservative therapy for 6 weeks. He was readmitted to the hospital with complaints of sudden back pain, numbness of both legs, and inability to walk 13 weeks after the fall. Magnetic resonance imaging findings were typical of spondylodiscitis. Gadolinium-enhanced T1-weighted magnetic resonance imaging indicated increased signal intensity at T11-T12 vertebral bodies and severe cord compression and epidural abscess at T11-T12 associated with infiltration of soft paravertebral tissues. On the seventh day after admission, he underwent partial laminectomy at T11 and posterior fusion at T9 to L2. The result of his blood culture was negative, but Aspergillus terreus was isolated from the material of T11-T12 intervertebral disc and vertebral bodies. His Aspergillus antigen was positive in a blood examination. Histological examination showed chronic suppurative osteomyelitis. On the 35th day after admission, he underwent anterior fusion at T11 and T12 with a rib bone graft. For 5 months, voriconazole was administered, and he wore a rigid corset. Posterior partial laminectomy at T11 and anterior fusion at T11 and T12 resulted in a good clinical course. The patient's neurological dysfunction was completely recovered, and his back pain disappeared. Two years after the operation, computed tomography was performed and showed bone fusion at T11 and T12. Magnetic resonance imaging revealed no evidence of increased signal intensity at T11-T12 vertebral bodies and severe cord compression and epidural abscess at T11-T12.

To our knowledge, this is the first report of spondylodiscitis caused by Aspergillus terreus after an abdominal penetrating injury. The histological finding of chronic suppurative osteomyelitis and the radiological findings strongly suggested direct inoculation of Aspergillus terreus.