Risk Factors for Recurrent Skin and Soft Tissue Infections in HIV-Infected Patients Over a 5-Year Period
Background: Skin and soft tissue infections (SSTIs) due to Staphylococcus aureus and other pathogens are common in human immunodeficiency virus (HIV) infected individuals, who are at high risk of recurrent SSTIs. We assessed risk factors for recurrent SSTI in a cohort of HIV-infected patients in an urban, largely African American population.
Methods: Retrospective cohort study of 511 HIV-infected patients at an academic medical center between 1/1/2005 and 12/31/2009, with medical record review of physician-diagnosed SSTIs, demographics, comorbidities, antibiotic exposure, and sexually transmitted infections (STIs). Patients with one or more SSTI during this period were analyzed. Time-varying variables were coded appropriately, including CD4+ count, HIV viral load (VL) and HAART use. Patients with and without SSTI recurrence were compared using a multivariate Cox regression analysis to assess associations of variables found to be univariate predictors of recurrent SSTI.
Results: 133 SSTIs occurred in 87 individuals, of whom 30 (34.5%) had a recurrent SSTI. 1 individual had 5 SSTIs, 4 had 4 SSTIs, 5 had 3 SSTIs, 20 had 2 SSTIs, and 57 had 1 SSTI. There were 118.3 person-years of follow-up for people at risk of recurrence. The incidence of second SSTI was 253.6 SSTIs/1000 person-years (95% CI 166.8-385.7). The 1-year risk of a second SSTI was 29.2% (95% CI 0.2027-0.4102), while the 5-year risk was 47.0% (95% CI 0.3439-0.6155). Risk factors for recurrent SSTI in the multivariate analysis included lymphedema (HR 6.4, p=0.018, CI 1.369-29.902) and non-viral hepatitis liver disease (HR 6.3, p=0.006, CI 1.709-22.989). The presence of an indwelling catheter (HR 6.2, p=0.055, CI 0.96-39.62) trended towards significance. Hemodialysis, currently taking HAART, CD4+ count, HIV VL, trimethoprim-sulfamethoxazole or azithromycin use, STI history, initial SSTI type, DM, or self-report of being a man who has sex with men were not associated with recurrence.
Conclusion: Of HIV-infected patients with an SSTI, nearly 1/3 had a recurrence within 1 year. Risk factors for recurrent SSTI were chronic lymphedema and non-hepatitis liver disease. CD4 count and HIV VL were not found to be significant risk factors for recurrence in contrast to findings of previous studies.
V. S. Hemmige,
E. Silverman, None
M. Z. David, None