J Clin Res Pediatr Endocrinol. Ahead of Print: JCRPE-84803 | DOI: 10.4274/jcrpe.galenos.2022.2021-12-24

A Novel Heterozygous NF1 Variant in a Neurofibromatosis-Noonan Syndrome Patient with Growth Hormone Deficiency: A Case Report

Si Qin, Yindi Zhang, Fadong Yu, Yinxing Ni, Jian Zhong
Department of Endocrinology, The Third Affiliated Hospital of Chongqing Medical University

Neurofibromatosis-Noonan syndrome (NFNS), a rare autosomal dominant hereditary disease, shows the manifestations of both neurofibromatosis type 1 (NF1) and Noonan syndrome. We present a case of NFNS with short stature due to the heterozygous nonsense variant of the NF1 gene. A 12-year-old boy was admitted for short stature, numerous café-au-lait spots, low-set and posteriorly rotated ears, sparse eyebrows, broad forehead and inverted triangular face, and nodular abnormal lesions revealed by cranial and spine magnetic resonance imaging. A novel heterozygous c.6189C > G (p.Tyr2063*) variant in NF1 gene was identified by the molecular analysis. Because exogenous growth hormone (GH) may enlarge nodular abnormal lesions, the patient did not receive GH treatment. During the follow-up, Lisch nodules were found in ophthalmologic examination. NFNS, a variant form of NF1, is caused by heterozygous mutations in the NF1 gene. The mechanism of GH deficiency caused by NF1 is still unclear. Whether NFNS patients should be treated with exogenous GH is still controversial.

Keywords: Neurofibromatosis Noonan syndrome, growth hormone deficiency, NF1 gene

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