A female baby was born after a non–‐eventful normal pregnancy.

For the first few days she was healthy but then started to vomit frequently.

Her mother noted that her urine had apeculiar ‘mousy’ smell.

When the infant was a month old she was admitted to hospital where they realised that the genetic screening test after her birth was deficient.

Her blood tests showed that the level of Phenylalanine Was (1.6 Mmol dm–‐3) reference value <0.1 Mmol dm–‐3.

Questions to be considered

1. What is the diagnosis for this baby?

2. Describe why this disease occurs and the mode of inheritance.

3. Explain why her urine smells differently from normal urine.

4. What are the clinical features you would expect to see?

5. How should she be treated?

6. What would happen if this child is not treated?

Filiano JJ. Neurometabolic diseases in the newborn. Clin Perinatol. Jun 2006; 33(2): 411-79.

Gassio R. School performance in early and continuously treated phenylketonuria. Pediatr Neurol. Oct 2005; 33(4): 267-71.