Amino acid metabolism( General & Phenyketonuria PKU)

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Valine is essential amino acid
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A one year old boy born to consanguineous parents is brought to your clinic with history of seizures.The child had normal birth weight and cried after birth.On examination, child is alert and no proper eye to eye contact, fontanelle are closed, microcephalic, mild spasticity in lower limbs and moving all his limbs, raised planter reflex, depigmented scalp hair. Child has peculiar mousy odor.Previous medical records show his outpatient visit for global developmental delay and he did not achieve social smile and head control by 2 months of age. MRI shows cerebral atrophy and bilateral diffuse white matter changes. Urine and serum amino acid levels , TSH, CPK levels are awaited. Guthrie test is positive. Which enzyme( s) deficiency could cause this disorder?
Which ketones are formed increased in urine and serum of a patient with PKU or what is the fate of Phenylalanine in PKU ?Phenylacetate, phenylpyruvate, phenyllactateYes/NO Early detection and treatment of PKU can prevent mental retardation in childrenyes.Yes/no Mental retardation seen in PKU is irreversible?YesWhy is brain atrophy seen in PKU? Which transporter is responsible for brain atrophy/ MR/Neurological signs in PKULNAAT Large neutral amino acid transporterClassical PKU is due to deficiency of ...............Phenyalanine a screening test for PKUGuthrie testWhich non essential amino acid becomes an essential amino acid in PKUTyrosineWhy should aspartame be avoided in PKU patientsAspartame contains phenylalanine and aspartic acid.A 20-year-old female with history of PKU conceives pregnancy.She is non complaiant with low phenylalanine diet.Which clinical manifestations can be seen in her child?Maternal PKU presents as congenital heart disease Growth retardation microcephaly and mental retardation in babies.Non classical PKU ( Malignant hyperphenylalaninemia) is caused by deficiency of ..............-DHPR- Dihydropteridine reductase -Defect in synthesis of BH4 from GTPA 2 year-old child with malignant PKU dies at 2 years of age besides being on strict low phenylalanine diet.Malignant pKU is due to deficiency of BH4, which is also required by tryptophan hydroxylase and tyrosine hydroxylase leading to synthesis of 5HT and L-dopa ( neurotransmitters ). Strict low phenylalanine diet only corrects hyperphenylalaninemia but NT deficiency still persists.What are screening methods for PKUGuthrie Bacterial Inhibition Assay (BIA), automated fluorometric assay, tandem mass spectrometry.A newborn tests positive for screening test for PKU.What is next step in management?1) Implement low phenylalanine diet immediately to prevent neurodevelopmental effects of PKU 2) Confirmatory test for PKUWhen is new born metabolic screening performed?It should be performed 24 hours after birth. If a new born recieves a screening befor 24 hours, it should be repeated in 2 weeks.( Current Practice guidelines 2020) ( infant presents with rigidity of his limbs.His serum and urinary phenylketone levels are elevated but the level of phenylalanine hydroxylase is normal in liver. Urinary metabolites of serotonin and catecholamines are reduced and donot respond to low phenylalanine diet. The rigidity respond to tetrahydrobiopterin. What is the diagnosis?Malignant hyperphenylalanemia /Non Classical PKU