Acanthosis nigricans – a potentially useful clue to the presence of significant occult disease at autopsy

A 19-year-old male was found dead in his apartment. At autopsy he was morbidly obese (Body mass index; BMI – 40.5) with multiple areas of velvety pigmented thickening of the skin in folds around the neck, in the axillae, in the inframammary regions, over the anterior waistline and groin regions and over the dorsal aspects of the feet. These had the typical appearance of acanthosis nigricans. Internal examination revealed aspiration of gastric contents into the airways. Vitreous humour biochemistry showed markedly elevated levels of both glucose (62.9 mmol/L) and β-hydroxybutyrate (13.54 mmol/L). Death was, therefore, due to aspiration pneumonia complicating diabetic ketoacidosis on a background of morbid obesity. The initial indicator of underlying diabetes, in conjunction with obesity had been acanthosis nigricans.