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Background Plasma concentrations of the anticoagulant dabigatran are correlated with clinical outcomes, and are affected by renal function, intestinal P-glycoprotein (P-gp) activity and stomach acidity. Aims To determine the adherence to dabigatran etexilate renal dosing guidelines, the frequency of co-prescription of potentially interacting drugs in patients on dabigatran, and how these related to dabigatran dosing. Methods A retrospective chart review of 204 patients discharged from a tertiary hospital on dabigatran etexilate over a 12-month period. Creatinine clearance, using the Cockcroft–Gault equation, was used as the surrogate of renal function in the 86 patients where this was calculable. Results Prescribed dabigatran etexilate dose rates in relation to creatinine clearance and the manufacturer's guidelines were classified as ‘standard’, ‘low’ and ‘high’ in 47% (40/86), 49% (42/86) and 5% (4/86) of patients respectively. Co-prescribed drugs that potentially interact with dabigatran etexilate were present in 75% (154/204) of patients and included strong P-gp inhibitors (16%, 32/204), proton-pump inhibitors (46%, 94/204) and anti-platelet drugs (47%, 95/204). Co-prescription of strong P-gp inhibitors was associated with the prescription of ‘low’ dose rates relative to renal function (P = 0.025). Conclusions Few patients were dosed excessively in relation to creatinine clearance. Around 50% was prescribed with ‘low’ dose rates in relation to creatinine clearance, which because of the association with co-prescription of strong P-gp inhibitors may be clinically appropriate. Most patients were co-prescribed with drugs that potentially interact with dabigatran etexilate.

An 83-year-old diabetic man receiving corticosteroids developed a forearm lesion. Histology confirmed the presence of a dematiaceous fungus, with associated granulomatous inflammation. Culture of a biopsy yielded fungal colonies with branching chains of single-celled, melanised, dry, sympodial conidia, which were identified as Cladophialophora devriesii on the basis of morphology and rDNA gene sequencing. To date, C. devriesii has been a relatively rare cause of human disease. To our knowledge, this is only the second case to be described, and the first report of infection in a UK resident.