Inborn error of amino acid and ketone body metobolism a beta keto thiolase defeciency; A rare case report

Abstract

Background : β-ketothiolase deficiency is an organic acid disorder that result from inability to process the amino acid isoleucine and ketone bodies. Its deficiency occurs in less than 1 in 100000 births. Till date around 60cases were reported from over 25 countries. It is inherited as an Autosomal recessive disorder. Mutation in the ACAT1 gene causes β-ketothiolase deficiency. It is characterized by an increased plasma glycine levels, metabolic acidosis and ketosis. Individuals with β-ketothiolase deficiency are at risk of developing metabolic crisis, particularly after fasting, illness/infection or high protein intake. Patients usually present with lethargy, ketosis, metabolic acidosis, feeding difficulty, fever, diarrhea, hypoglycemia /hyperglycemia and sometimes as coma or death. Methods : 6 months male child born out of 3rd degree consanginous marriage presented with Acute gastroenteritis with severe dehydration and high anion gap metabolic acidosis with altered sensorium, schock and without organomegaly not responding fluid management and ionotropes. Subsequently child was found to have hyperglycemia and ketonuria for which child was treated as per protocols of DKA and also added antibiotics empirically suspecting sepsis but child had persistent severe ketoacidosis and poor GCS inspite of normoglycemia which led to suspicion of IEM for which urine for GC-MS which was suggestive of beta keto thiolase defeciency. Results : Inspite of adequate fluid and bicarbonate corrections child repeatedly had metabolic crisis and succumbed to death. Conclusion : An infant with Acute gastroenteritis with severe dehydration and presenting features of DKA if not responding to initial management and having persistent ketosis with altered sensorium could be a possible IEM and ealrly diagnosis of which would result in improved outcome with best possible interventions and also useful in perinatal diagnosis.