Hyperprolinemia type II: identification of the glycine conjugate of pyrrole-2-carboxylic acid in urine.

The urinary organic acids were studied in two cases of hyperprolinemia Type II, using various combinations of chromatographic, electrophoretic and mass spectrometric techniques. In both cases N-(pyrrole-2-carboxylic acid) was idenfitied as a major urinary metabolite. While there was evidence for an additional conjugate of this pyrrolic acid, no free pyrrole-carboxylate could be detected in the urine from either case.