Infections of the spine in patients with human immunodeficiency virus.

Background: Musculoskeletal infections in patients with the human immunodeficiency virus (HIV) have been described. However, the prevalence, specific characteristics, and outcomes of spinal infections in these patients have not been studied in a large group of patients to our knowledge.

Methods: The computerized records of all patients discharged with the diagnosis of spinal osteomyelitis, discitis, epidural abscess, or tuberculosis from our institution from October 1994 through September 2000 were reviewed. Patients with the diagnosis of HIV were identified, and the charts were examined in detail.

Results: During the six-year period, 7338 unique patients who were HIV positive were admitted. Seventeen (0.23%) of them were treated for a spinal infection. The prevalence of spinal infection was 23.2 per 10,000 admissions of HIV-positive patients and 7.1 per 10,000 admissions of HIV-negative patients (p < 0.0001). Eight patients who had discitis and/or osteomyelitis had a mean CD4 T-cell count of 339.6 cells/mm(3), and all eight had clinical resolution of the infection after six to twelve weeks of appropriate antibiotic therapy. In contrast, six patients who had spinal tuberculosis had a mean CD4 count of 75.7 cells/mm(3) (p = 0.005), and one of them died during the hospitalization. The remaining three patients, who had epidural abscesses, had a mean CD4 count of 20.67 cells/mm(3) (p = 0.001), and two of them died.

Conclusions: Discitis and/or osteomyelitis occurs in HIV-positive patients with a mild-to-moderate decrease (>/=200 cells/mm(3)) in the CD4 T-cell count, and the infection responds to appropriate antibiotics. Patients with a more severely decreased CD4 count (50 to 200 cells/mm(3)) may have spinal tuberculosis develop, and patients with the lowest CD4 counts are more likely to have epidural abscesses develop. The three fatalities in this study occurred in these two groups of patients. As a group, HIV-positive patients are significantly more likely to have a spinal infection develop than are HIV-negative patients (p < 0.0001). Although the CD4 count can be used as a predictor of the clinical course, identification of the organism remains paramount in the treatment of this complex patient population.