Type 2 diabetic female with vildagliptin associated eczematous eruption

A 54-year-old woman was referred for dermatology consultation with a history of red, severely itchy lesions over the back and upper extremities. She complained of recent onset elevated lesions with dark coloured pigmentation over the same area. There was no personal or family history of atopy. On examination, there were few eczematous papules of variable sizes (maximum up to 1 cm diameter) distributed on the back and upper extremities. Additionally, she had mild lichenification (figure 1). Serum immunoglobulin E was 856 IU/mL and eosinophil count was 8.2%. She was prescribed oral antihistaminics and 0.05% clobetasol propionate cream for local application. However, the lesions were unchanged and pruritus also worsened, interfering with sleep. She was a type 2 diabetic for the past 4 years and currently taking voglibose, metformin and vildagliptin. Notably, vildagliptin was introduced into her regimen 2 months prior to the onset of eczematous skin eruptions. Her glycosylated haemoglobin was 7.9%.