Urinary excretion of D-glucaric acid, total glucuronic acid and total porphyrins in porphyria cutanea tarda.

The urinary levels of D-glucaric acid, which is an index of hepatic microsome induction, and the excretion of glucuronic acid and porphyrins were measured in nine patients with Porphyria Cutanea Tarda (PCT) and twelve normal controls. The excretion of D-glucaric acid and glucuronic acid were respectively 3.5 and two times higher in PCT patients compared to controls. A statistical correlation could be demonstrated between urinary excretion of total porphyrins with that of glucaric and glucuronic acids. These findings indicate that microsomal function and porphyrin metabolic derangement are strictly related in PCT.