Precocious puberty in children with neurofibromatosis type 1,☆☆,,★★

Presented in part at the Midwest Society for Pediatric Research, Nov. 4, 1992, Chicago, Ill., and the Fourth Joint Meeting of the Lawson Wilkins Pediatric Endocrine Society and the European Society for Pediatric Endocrinology, June 1993, San Francisco, Calif.
https://doi.org/10.1016/S0022-3476(95)70449-3Get rights and content

Abstract

We undertook a comprehensive study of children with neurofibromatosis type 1 (NF-1) cared for in a large multidisciplinary clinic to determine the prevalence of precocious puberty and its relationship to optic pathway tumors (OPTs). Precocious puberty was diagnosed in 7 of 219 children with NF-1 (5 boys and 2 girls) examined between Jan. 1, 1985, and April 20, 1993. All seven children had OPTs involving the optic chiasm; they represented 39% of children with NF-1 and chiasmal tumors (95% confidence interval, 17% to 64%). Eleven prepubertal children (aged 2 to 10 years) with NF-1 and OPTs, and age- and sex-matched NF-1 control subjects without OPTs, underwent luteinizing hormone-releasing hormone (LH-RH) stimulation tests. Two boys with OPTs had pubertal luteinizing hormone (LH) responses, and testosterone levels >10 ng/dl. Basal LH levels were also elevated in these two boys when tested with a very sensitive immunochemiluminometric assay. None of the children without an OPT had either a pubertal response to LH-RH or an elevated basal LH level. We conclude that precocious puberty in children with NF-1 is found exclusively in those who have OPTs involving the optic chiasm; it is a common complication in those children. With the use of a highly sensitive LH assay, biochemical evidence of hypothalamic- pituitary-gonadal axis activation may be demonstrated, even without provocative testing. (J PEDIATR 1995;126:364-7)

Section snippets

METHODS

The Children's Memorial Hospital Neurofibromatosis Clinic is a multidisciplinary clinic that provides consultation services to assist in the diagnosis and management of neurofibromatosis in children. All children are seen at least annually and are examined by a general academic pediatrician, a geneticist, and a pediatric ophthalmologist at each visit. Patients seen in this clinic between Jan. 1, 1985, and April 20, 1993, were the subjects of this study. NF-1 was diagnosed in each subject on the

RESULTS

Two hundred nineteen children with NF-1 were examined during the period of study, and precocious puberty was diagnosed in seven of them (3%). All seven children who had precocious puberty had abnormal LH-RH test results. Of the 219 children, 171 underwent neuroimaging. All the children with precocious puberty had tumors involving the optic chiasm (Table I); they represented 39% of children with chiasmal tumors (95% confidence interval, 17% to 64%). Fifty-seven percent of the children without

DISCUSSION

The main finding of this study is that precocious puberty was found exclusively in those children with NF-1 who had OPTs involving the optic chiasm. Previous reports of this association in the absence of OPTs may have erroneously included children with McCune-Albright syndrome, in whom café au lait spots and precocious puberty may also occur. Saxena3 reported two examples of precocious puberty occurring in NF-1 without tumors of the optic chiasm, but neither computed tomography nor magnetic

References (19)

There are more references available in the full text version of this article.

Cited by (0)

From the Department of Pediatrics, Northwestern University Medical School, and the Divisions of Endocrinology, General Academic and Emergency Pediatrics, and Genetics, Children's Memorial Hospital, Chicago, Illinois

☆☆

Supported in part by the National Center of Research Resources and General Clinical Research Centers Program, RR00078, and a grant from the Children's Memorial Institute for Education and Research.

Reprint requests: Joel Charrow, MD, Division of Genetics-59, Children's Memorial Hospital, 2300 Children's Plaza, Chicago, IL 60614.

★★

0022-3476/95/$3.00 + 0 9/20/60907

View full text