Endocrine Abstracts

Patient Demographics: 22-month-old female, severe failure to thrive.

Past History: Birth weight 5 lb 11 oz at term, grew well for 4 months and then deviating progressively below the curve in height and weight.

Physical exam: Length 66 cm (−5.1 SD), weight 6.6 kg (−6.7 SD). Prominent forehead and midfacial hypoplasia noted. Muscle mass decreased.

Family history: Mother’s height of 5 ft 3 inches with menarche at age 13. Father, – 4 SD, diagnosed with isolated growth hormone deficiency at 7 years of age, and treated (5 ft 4 inches). Siblings included a 6-year-old brother who was very small at age 22 months during an endocrine evaluation and a 3-year-old sister with height and weight at both −4 SD below the mean.

Evaluation (studies/assessment): Free T4 1.28 ng/dL (normal 1.1−1.7), TSH 1.8 uU/mL. IGF-1 <25 ng/mL (44–174) and IGFBP-3 <0.5 ug/mL (1.3–3.5) were both very low. Growth hormone stimulation testing peak 1.1 ng/mL. DNA sequencing of the GH-1 gene found a heterozygous sequence variance.

Interventions (physiologic or psychosocial): Growth hormone therapy started at 0.27 mg/kg/week and headaches began 5 days later, likely due to increased intracranial pressure, GH stopped and dose reduced by 1/3 which was tolerated. She has grown about 12 cm (first 10 months) but is still −3.5 SD.

Discussion/recommendations: Failure to thrive in the first 2 years of life rarely has an endocrine etiology. In this case, recognizing the importance of the family history and better compliance with follow-up care of the older siblings might have resulted in earlier diagnosis and treatment of these patients. In addition, the headaches likely due to benign intracranial hypertension in the first case suggests that this rare complication of GH therapy might be more common in children with this rare and severe form of GH deficiency, so starting GH at lower doses than usual would be prudent.