Growth, Puberty, and Endocrine Functions in Patients With Sporadic or Familial Neurofibromatosis Type 1: A Longitudinal Study

This study prospectively evaluates parameters of growth, puberty, and attained adult height in children with sporadic or familial occurrence of neurofibromatosis type 1 (NF-1), followed up longitudinally, to define the most important factors affecting these parameters. The study was made up of 89 patients (55 boys, 34 girls) with sporadic (n = 45) or familial NF-1 (13 affected fathers and 31 affected mothers). The average age at referral was 8.9 years (range 8.5-15 years), and the average follow-up period was 8.5 years (6-15 years). A total of 28 patients attained adult height at the time of the report. Anthropometric measurements and bone age determinations were performed at 6- to 12-month intervals. As indicated, central nervous system (CNS) imaging was performed on 60 patients. Serum levels of thyroid stimulating hormone, free T4, lutheinizing hormone, follicle stimulating hormone, testosterone or estradiol, cortisol, and prolactin were measured in all patients periodically, and the pituitary growth hormone reserve was assessed in 32 short patients. CNS pathology was found in 23 of the 89 patients. A total of 6 patients required neurosurgery, and 2 patients had cranial irradiation. Of these patients, 3 were receiving recombinant growth hormone and thyroxin replacement therapy and 5 patients with precocious puberty were treated with a gonadotropin-releasing hormone analog. All other patients had normal endocrine tests. Precocious puberty was recorded in 5 patients and was more common among the familial cases. The 5 patients with precocious puberty also had CNS pathology. Short stature (90th percentile) was observed in 4 of 89 patients (4.5%), who all had CNS tumors. A highly significant correlation was found among all adult height-predicting parameters (r =.79), and attained adult height was best cor