Fixed drug eruption caused by fluconazole

Objective: to characterize a group of patients with fixed drug erythema (FDE) caused by fluconazole to determine the sensitivity and specificity of the local provocative application test (LPAT) and to evaluate cross-allergenic reactivity with other antifungal drugs of the azole group.Materials and methods: a prospective study was conducted in the period from 2012 to 2022. 347 patients with delayed drug hypersensitivity (DDH) were consulted, FDE could be suspected in 86 patients (24.8%), of which 23 patients were caused by fluconazole (26.8%). We included patients with suspected fluconazole FDE (n=23). LPAT with fluconazole was performed in 12 patients, drug provocation test (DPT) with ketoconazole – 17, DPT with itraconazole – 15, DPT with fluconazole – 1.Results: the ratio of men and women was 1:6.3, the average age was 30.39±10.23 years. In 1 patient, the diagnosis of FDE caused by fluconazole was withdrawn. Number of reactions: 1 – in 2 patients (9.1%), more than one reaction – in 20 (90.9%). 4 patients (18.2%) had atopy. Sensitivity of LPAT for diagnosing DDH in FDE caused by fluconazole was 41.7%, specificity – 100%, false-negative rate – 58.3%, positive predictive value – 100%. DPT with ketoconazole, itraconazole was negative in 100% of cases.Conclusions: the results obtained allow us to conclude that FDE caused by fluconazole in the vast majority of cases developed in women aged 19 to 30 years. Since patients with FDE caused by fluconazole tolerate ketoconazole and itraconazole well, it is highly likely that they can switch from fluconazole to one of these drugs. LPAT should be used for diagnosing FDE caused by fluconazole, since it was absolutely safe for the patient and allowed avoiding DPT in 42% of patients. Importantly that the timely and correct diagnosis in more than 90% of cases, it was possible to prevent the development of a repeated reaction to fluconazole.