Not a feature of Hartnup's disease:
c. Mental retardation(Ref: Nelson's 20/e p 636-642, Ghai 8/e p 653-655)Clinical features of Hartnup disease:Most children with Hartnup defect remain asymptomaticMajor clinical manifestation in symptomatic patient is cutaneous photosensitivity: pellagra-like rash on sun exposureSome patients may have intermittent ataxia & Psychological disturbances, but mental development is usually normal.
Pellagroid skin lesion
Cerebellar ataxia
Mental retardation
Psychological disturbances
Inborn Errors of Metabolism