A 10-year-old girl is referred for further evaluation of short stature and inadequate weight gain. Her birth weight was within the normal range and she is an active and lively child. While all developmental milestones were achieved within the expected time periods, her dentition has been delayed. There is no history of systemic illnesses such as recurrent infections, malabsorption disorders, or childhood malignancies, and she is not on any medications currently. She has not been exposed to radiation, and has not experienced cranial trauma. Both parents are of average height. A detailed dietary assessment reveals an appropriately balanced diet. All vaccinations are up to date. All basic investigations, including a complete blood count, serum electrolyte assay, stool analysis, and liver and renal profiles are within normal parameters. However, x-rays of her left hand and wrist are suggestive of a bone age of 7 years.
Her karyotype is 46,XX
IGF-1: 10 ng/mL (49-289); a follow-up insulin tolerance test shows a rise < 10 μg/L. The thyroid profile is within normal parameters.
No structural abnormalities observed.
There are no intracranial masses.