Therapeutic failure in scabies : An observational study

Background. - Several sources suggest an escalation of scabies in ă France. ă Aim. - To describe a population of patients continuing to present with ă scabies despite multiple treatments in order to identify factors ă associated with persistence of infection. ă Patients and methods. A descriptive cross-sectional study in adults and ă children consulting for persistent scabies despite at least one previous ă treatment. A standardized questionnaire explored potential sources of ă treatment failure. ă Results. - Thirty-one patients were analyzed. Initial symptoms were ă noted to have started between two and 52 weeks earlier (mean: 19 weeks). ă The mean number of prior consultations with a general practitioner was ă 3.1 (0-10) and 1.7 with a dermatologist (0-7). The mean number of ă patients per household was 3.5 (1-9). At least one dose of oral ă ivermectin (maximum of 6 doses per household) was prescribed for 84% of ă patients (29% of whom were not fasted at the time). Further, 74 % of ă patients received at least one local application of esdepallethrin and ă piperonyl butoxide (maximum: 5 courses), four received benzyl benzoate ă and two received permethrin; however, 58 % did not reapply the ă substance after hand washing. All households bought the prescribed ă treatments despite the costs. Close contacts of patients were treated in ă 58% of households. Decontamination of bedding and clothing was carried ă out properly in 90% of households. ă Discussion. - Persistence of infection appears to be linked to: (1) ă insufficient treatment of close contacts; (2) absence of a second ă treatment between days 7 and 14; (3) insufficient efficacy of the ă available treatments, doubtless due to multiple factors (intrinsic ă resistance of Sarcoptes, failure to repeat treatment, poor explanation ă of methods for dosing and application, and oral intake of treatments). ă Access to non-reimbursed treatments was not identified as a problem and ă decontamination of bedding and clothing was correctly performed in most ă cases. ă Conclusion. Though certain fundamental aspects of scabies treatment must ă be better known, longer consultations and provision of efficacious ă treatments are also a priority. (C) 2015 Elsevier Masson SAS. All rights ă reserved.