Staphylococcus aureus resistance to topical antimicrobials in atopic dermatitis

Abstract: Background: Topical antimicrobial drugs are indicated for limited superficial pyodermitis treatment, although they are largely used as self-prescribed medication for a variety of inflammatory dermatoses, including atopic dermatitis. Monitoring bacterial susceptibility to these drugs is difficult, given the paucity of laboratory standardization. Objective: To evaluate the prevalence of Staphylococcus aureus topical antimicrobial drug resistance in atopic dermatitis patients. Methods: We conducted a cross-sectional study of children and adults diagnosed with atopic dermatitis and S. aureus colonization. We used miscellaneous literature reported breakpoints to define S. aureus resistance to mupirocin, fusidic acid, gentamicin, neomycin and bacitracin. Results: A total of 91 patients were included and 100 S. aureus isolates were analyzed. All strains were methicillin-susceptible S. aureus. We found a low prevalence of mupirocin and fusidic acid resistance (1.1% and 5.9%, respectively), but high levels of neomycin and bacitracin resistance (42.6% and 100%, respectively). Fusidic acid resistance was associated with more severe atopic dermatitis, demonstrated by higher EASI scores (median 17.8 vs 5.7, p=.009). Our results also corroborate the literature on the absence of cross-resistance between the aminoglycosides neomycin and gentamicin. Conclusions: Our data, in a southern Brazilian sample of AD patients, revealed a low prevalence of mupirocin and fusidic acid resistance of S. aureus atopic eczema colonizer strains. However, for neomycin and bacitracin, which are commonly used topical antimicrobial drugs in Brazil, high levels of resistance were identified. Further restrictions on the use of these antimicrobials seem necessary to keep resistance as low as possible.

Tratamento da doença de Hailey-Hailey com toxina botulínica tipo A / Hailey-Hailey disease treatment with Botulinum toxin type A

Duas irmãs com doença de Hailey-Hailey, com lesões recorrentes - uma em axilas e outra em região inguinal -, e resposta limitada aos tratamentos clássicos. Elas foram tratadas com aplicação de toxina botulínica tipo A. Observamos que houve importante melhora na paciente tratada na região inguinal e remissão completa na paciente em cujas axilas sofreram tratamento. Além disso, foi possível poupar uso de antibióticos sistêmicos e corticoides tópicos. O alto custo é um fator restritivo para uso rotineiro e estudos maiores são necessários para definir eficácia e relação custo-benefício dessa intervenção.

Two sisters with recurrent lesions, one on axillae and other on the groin, and with limited response to classical treatments were treated with injections botulinum toxin type A. We observed marked improvement in the patient treated in the groin and complete remission in the patient treated in the axillae. It was possible to spare the use of systemic antibiotics and topical corticosteroids. The high cost is a restrictive factor to routine use and large studies are necessary to access efficacy and cost benefit profile.