TNF and diabetes mellitus: Based on conditional logistic regression, anti-TNF use was not significantly associated with SSSTI (OR 1.1, 95% CI: 0.61-2.03, p = 0.92) but patients with diabetes mellitus (OR 2.5, 95% CI: 1.53-4.13, p < 0.01) or a history of skin infection (OR 5.7, 95% CI: 2.87-11.43, p < 0.01) were more likely to have SSSTI.