Metabolic

Question 1

What are differences between Tay Sachs and Niemann Pick Type A?

Answer 1

• Tay Sachs - hyperreflexia whereas Niemann Pick hyporefexia.
• Tay Sachs - macrocephaly, not a feature of Niemann Pick.

Question 2

What is the best way to determine a urea cycle defect on blood?

Answer 2

• Alkalosis due to build up of ammonia which is alkali.
• Infants appear normal initially but rapidly develop cerbral oedema and related signs of lethargy, anorexia, hyper/hypoventilation, hypothemia, seizures, neurologic posturing and coma.

Question 3

In what condition is extensive dermal melanocytosis seen?

Answer 3

• Hurler syndrome.

Question 4

What are the clinical manifestations of Zellweger syndrome?

Answer 4

• Disorder of peroxisomal biogenesis (Cerebrohepatorenal syndrome).
• Considered an adrenoleukodystrophy.
• Spectrum of disorders caused by mutation in PEX genes.
• Neurologic manifestations include - neuronal migration disorders, white matter abnormalities and lipid storage.
• High levels of plasma VLCFA is characteristic.

Question 5

What are the features of biotin deficiency?

Answer 5

• Absence of biotinidase, results in biotin deficiency.
• Atopic or seborrheix dermatitis, alopecia, ataxia, myoclonic seizures, hypotonia, developmental delay, sensorineural hearing loss and immunodeficiency (T cell abnormalities) may ooccur.
• Lab findings include: metabolic acidosis, ketosis, hyperammoniaemia and presence of organic acids.