High levels of fusidic acid-resistant Staphylococcus aureus despite restrictions on antibiotic use

High rates of fusidic acid (FA)-resistant Staphylococcus aureus (FRSA) in patients with skin disease have been previously attributed to high usage of topical FA.

To assess whether local community guidelines to restrict topical FA has affected its prescription and use and the level of FRSA in patients with skin disease.

Stapylococcus aureus isolates from microbiology samples received over a 4-month period in 2004 were tested for antibiotic sensitivities. Comparison was then made with the results of a previous study carried out in 2001.

A significant fall was seen in the use of topical FA in dermatology patients. In 2001, 62% of patients had used FA-containing preparations within the previous 6 months, compared with just 15% of patients in 2004 (P < 0.001). The number of topical FA prescriptions in primary and secondary care dropped between 2001 and 2004. The proportion of S. aureus isolates resistant to FA in dermatology patients had not significantly fallen between 2001 (50%) and 2004 (41%) (P = 0.4). However, there was a significant increase in FA resistance within hospital inpatients, nondermatology outpatients and primary-care patients (P < 0.05). The FRSA level had doubled in hospital inpatients (20%) and almost tripled in nondermatology outpatients (28%) and primary care patients (25%).

Persistent high levels of FA resistance may represent the development of an FRSA reservoir in the community. Continued restriction of FA is still recommended.