A child has microcephaly, Blue eyes, Fair skin, and Mental retardation, Ferric chloride test is positive. What is the likely diagnosis -

Ans. is 'a' i.e., Phenylketonuria Clinical manifestations of phenylketonuria o Normal at bih o Symptoms occur after 1 months - i) Mental retardation ----> Not present at bih, develops gradually. ii) Neurological signs -4 Irritability, tremors, convulsions, hyperkinesis and muscular hypeonia & Exagerated reflex. iii) Blond hair, blue iris, fair skin. iv) Musty or mousy body odour. v) Vomiting vi) Microcephaly vii) Enamel hypoplasia & Growth retardation