In a pregnant woman with raised phenylalanine in blood, offspring is most likely to have:
Ans: a (Mental retardation) Ref: Nelson, 17th ed, 400; 18th ed, p. 531Question is about pregnancy with hyperphenylalaninimea.Pregnant women with hyperphenylalaninimea who are not receiving phenylalanine restricted diet cany a very high risk of having an offspring with mental retardation, microcephaly and congenital heart disease.These complications are related to high levels of maternal plasma phenylalanine during pregnancy.Prospective mothers who have been treated for hyperphenylalaninimea should be maintained on a phenylalanine restricted diet before and during pregnancy, and should be made to keep blood phenylalanine level below 6 mg/dl throughout pregnancy.PHENYLKETONURIA~ Deficiency of phenylalanine hydroxylase~Normal at birth~ Progressive MR- loses 4 points in IQ/month in 1 st year~Purposeless movements- rocking / athetosis~ Fair skin and blue eyes~ Rash eczematoid / seborrheic~ Mousy/ musty odour~ Hypertonia with hyper rellexia~ 25% shows seizures 50% will have EEG abnormalities~ Microcephaly~Enamel hypoplasia~ FIT -growth retardationDiagnosis:At birth urine test is negative, blood phenylalanine may be increased.Estimation is better done after protein challenge (breast feed).Guthrie test (Bacterial inhibition test) is used to detect level of phenylalanine in blood.Ideally done 48-72 hours after protein feed.Treatment:Low phenylalanine diet (level 3-15 ng/dl)FeCk testPhenylketonuriaGreen colourMaple syrup urine diseaseNavy blue colour
Mental retardation
Lighter complexion
Microcephaly
Reduction of limb growth
Inborn Errors of Metabolism