SINCE Gunther's original description of acute porphyria as a clinical entity was published in 1911, a number of reviews1have appeared on the subject. Although porphyria and porphyrinuria have been associated with many toxic states and with other disease entities,1a,fthe only reference in the literature to an association of acute porphyria with diabetes mellitus seems to be the statement, "... it has also been found in diabetes mellitus," appearing in the section on porphyria in Duncan's textbook.2 At the Albert Merritt Billings Hospital there are, at the time of this report, records of a total of 8 proved cases of acute porphyria, in 3 of which the diagnosis of diabetes mellitus was also substantiated. In each case, the diabetes had been present for some years before symptoms of porphyria appeared. The apparently complete dissociation of pigment metabolism and carbohydrate metabolism makes it difficult to suggest an