Inborn errors of metabolism

Question 1

What is biochemical genetics?

Answer 1

The study/investigation of (primarily) genetic disorders that affect the metabolic pathways of cells

Question 2

What are the 3 main categories of inborn errors of metabolism?

Answer 2

• accumulation of toxin
• energy deficiency
• deficient production of essential metabolite/structural component

Question 3

What are the clinical effects of acute hyperammonaemia toxicity?

Answer 3

lethargy, poor feeding, vomiting, tachypnoea, convulsions, coma, death

Question 4

What accumulates in patients with urea cycle defects?

Answer 4

ammonia

Question 5

What causes androgen insensitivity syndrome?

Answer 5

defective receptors

Question 6

How does androgen insensitivity syndrome present?

Answer 6

primary amenorrhoea, infertility

Question 7

What do Leeds test in a basic urine metabolic screen?

Answer 7

spot tests, organic acids, amino acids, sugar chromatography, oligosaccharides, mucopolysaccharides

Question 8

What are the clinical problems of homocystinuria?

Answer 8

mental retardation, marfinoid habitus, ectopia lentis, osteoporosis, thromboembolism

Question 9

defects in branched chain amino acid catabolism are?

Answer 9

classic organic acidaemias