A 5 day old child presents with intractable seizures. He had rashes all over the body. Blood examination showed hyperammonemia and lactic acidosis. The probable diagnosis is -

Ans. is 'a' i.e., Organic aciduria Organic aciduria (organic acedimial o Organic aciduria is a term used to classify a group of metabolic disorders which disrupt normal amino acid metabolism, paicularly branched chain amino acids (isoleucine, leucine, valine) causing a build of acids which are usually not present. o The main types of organic acidemia are : - i) Methylmalonic acidemia ii) Propionic acidemia iii) Isoavleric acidemia iv) Maple syrup urine disease vi) Glutaric acidemia v) Combined (multiple) carboxylase deficiency Clinical manifestations o Neurological damage --> Mental retardation, Seizures, Lethargy, Vomiting. o Developmental delay o Malnutrition o Poor feeding and slow growth o Hypoglycemia o Hypotonia o Metabolic acidosis (Lactic acidosis) o Ketoacidosis o Hyperammonemia o Rash, alopecia and ataxia in some organic aciduria. Mitochondrial encephalopathv (MELAS) o Encephalopathy o Lactic acidosis o Stroke like episodes Blindness, paralysis, vomiting. Disorders of the urea cycle o Ammonia is mostly derived from the catabolism of aminoacid and is coveed to an amino group in urea by enzymes of urea cycle. So, defects in enzymes of urea cycle cause --> i) Hyperammonemia ii) Encephalopathy iii) Vomiting