A child has microcephaly, blue eyes, fair skin, and mental retardation; ferric chloride test is positive. What is the likely diagnosis?
High-Yield Explanation
-The given scenario suggests diagnosis of Phenylketonuria (PKU). -C/F of Phenylketonuria: Blonde hair, Blue iris, Fair skin Musty/ mousy body odour Microcephaly Intellectual disability due to toxic levels of Phenylalanine and insufficient tyrosine Growth Retardation Dental enamel changes Irritability , Tremors , Convulsions, Hypeonia -OTHER OPTIONS : Homocystinuria- seizures, marfanoid features, ectopia lentis, thromboembolism Tyrosinosis- hepatomegaly, peripheral neuropathy Alkaptonuria- ochronosis, urine turns black on standing, ahritis