Answers-5 The following inborn errors of amino acid metabolism are associated with abnormal odours: Glutaric acidaemia type II (sweaty feet), hawkinsinuria (swimming pool), isovaleric acidaemia (sweaty feet), maple syrup urine disease (maple syrup), methionine malabsorption (cabbage), multiple carboxylase deficiency (tomcat urine), oasthouse urine disease (hops-like), phenylketonuria (mousy or musty), trimethylaminuria (rotting fish), tyrosinaemia (rancid, fishy or cabbage-like). In addition, ketones may be smelt in diabetic ketoacidosis, and some intermediary disorders of fatty acid metabolism can result in fishy smells. The general rule is that if a child smells peculiar he requires a metabolic work-up.