Risk factors for fluconazole-resistant candidiasis in human immunodeficiency virus-infected patients

In a case-control study to identify risk factors for fluconazole-resistant oroesophageal candidiasis in human immunodeficiency virus-infected patients, 25 patients with clinical and in vitro fluconazole-resistant candidiasis were paired with controls who had treatment-responsive candidiasis and who had been observed for similar time periods. After their first episode of candidiasis, patients who later developed fluconazole resistance had more treated episodes than did matched controls (cases, 3.1; controls, 1.8; P = .004), lower median CD4 cell counts (11/mm3 vs. 71/mm/3; P = .004), and greater median durations of all antifungal therapy (419 vs. 118 days; P < .001) and of systemic azole therapy (272 vs. 14 days; P < .001). When paired with a second set of controls matched by CD4 cell count as well as first diagnosis of candidiasis, cases continued to show greater median exposure to azoles (272 vs. 88 days; P = .005). These data indicate that advanced immunosuppression and exposure to oral azoles are risk factors for the development of fluconazole resistance.