Abstract
Screening for metabolic abnormalities of Trp has been introduced using SPE pretreatment, TLC and/or two HPLC procedures. The excretory pattern in urine (occasionally also plasma and CSF levels) has been followed in a group of 390 children showing various symptoms of a metabolic defect and in 195 patients with skin diseases, namely those associated with photosensitivity, such as porphyria, vitiligo, alopecia, psoriasis, erythematodes, and others.
Excretory abnormalities of either indican, kynurenine, 3-hydroxyanthranilic acid or indolylacryloylglycine have been occasionally combined with myopathy, seizures, liver and intestinal symptoms. Several indoles and kynurenine derivatives present changes in the alopecia group and the vitiliginous patients.