Cutaneous Mycobacterium chelonae infection in Edinburgh and the Lothians, South-East Scotland, UK

Background We reviewed all cases of Mycobacterium chelonae infection seen in our department between 1 January 2008 and 31 December 2012. Objectives To review the epidemiology, clinical features and management of cutaneous M. chelonae in South-East Scotland, and to compare prevalence data with the rest of Scotland. Methods The Scottish Mycobacteria Reference Laboratory database was searched for all cases of cutaneous mycobacterial infections. Results One hundred and thirty-four cases of cutaneous mycobacterial infection were recorded. Sixty-three were tuberculous; of the remaining 71, M. chelonae was the most common nontuberculous organism (27 cases). National Health Service (NHS) Lothian Health Board was the area with highest incidence in the Scotland (12 cases). Three main groups of patients in the NHS Lothian Health Board contracted M. chelonae: immunosuppressed patients (n = 6); those who had undergone tattooing (n = 4); and others (n = 2). One case is, we believe, the first report of M. chelonae cutaneous infection associated with topical corticosteroid immunosuppression. The majority of patients were treated with clarithromycin monotherapy. Conclusion The most prevalent nontuberculous cutaneous mycobacterial organism in Scotland is M. chelonae. The prevalence of M. chelonae in Edinburgh and the Lothians compared with the rest of Scotland is disproportionately high, possibly owing to increased local awareness and established facilities for mycobacterial studies. Immunosuppression with prednisolone appears to be a major risk factor. The first outbreak of tattoo-related M. chelonae infection in the U. K. has been reported. Clinicians should be aware of mycobacterial cutaneous infection and ensure that diagnostic skin samples are cultured at the optimal temperatures.