MSFinals-4290
A 6-month-old girl with poor weight gain is brought to see the pediatrician. Her growth has slowed crossing 1 centile but her weight has fallen from 50th to 9th centile in the last two months.
She began weaning at 4 months with a variety of foods. Her mother says she eats well and has no other specific symptoms. On examination she appears emaciated with abdominal distension. She is rolling over and making appropriate cooing sounds.
What is the probable diagnosis?