MANCHESTER, ENGLAND — Levels of fusidic acid-resistant Staphylococcus aureus have not fallen despite efforts to limit the use of this topical antibiotic, which suggests that a community reservoir of resistance has developed, Dr. Angana Mitra said at the annual meeting of the British Association of Dermatologists.
High levels of fusidic acid-resistant S. aureus (FRSA) have been reported in the United Kingdom previously, particularly in dermatology patients. In an audit done over a 4-month period in 2001, resistant isolates were identified in 50% of dermatology patients, in 9% of primary care patients, 10% of hospital inpatients, and 10% of nondermatology outpatients, said Dr. Mitra of the department of dermatology, Dewsbury District Hospital, West Yorkshire, England. An active education program was undertaken on the appropriate use of topical antibiotics, and a repeat audit was done over the same 4-month period in 2004.
The total number of S. aureus isolates was much higher in 2004, at 604, than in 2001, at 349. This is likely to reflect an increased awareness of antibiotic resistance in general, with more swabs being taken, she said.
In 2001, the level of FRSA in primary care, hospital inpatients, and nondermatology outpatients was similar, at 10%. In comparison, at that time, 50% of dermatology patients had FRSA. The level in dermatology fell slightly and not significantly by 2004, to 41%. However, the level had doubled among hospital inpatients and almost tripled in primary care and nondermatology outpatients.
Topical fusidic acid use within the previous 6 months was reported by 63% of dermatology patients in 2001 (Br. J. Dermatol. 2003;148:1018–20). This fell to 15% in 2004.
Hospital prescriptions for topical fusidic acid also fell, from an average of 42 per month to 1–2 per month, and the number of community prescriptions also decreased significantly, but there was no corresponding drop in FRSA, Dr. Mitra said. Persistence of FRSA suggests the presence of a reservoir in the community, and there may be a lag period before this clears. “We therefore advocate continued control on topical fusidic acid use,” she said.
The drug should be used for short periods and for appropriate indications. In 2001 and 2004, the most common reason for using fusidic acid was not staphylococcal skin infection but atopic eczema, said Dr. Mitra, adding that, for the first time, FRSA also resistant to methicillin was identified in 11% of patients.