Cleft palate and hypopituitarism in a patient with Noonan-like syndrome with loose anagen hair-1

Noonan syndrome (NS), the most common of the RASopathies, is a developmental disorder caused by heterozygous germline mutations in genes encoding proteins in the RAS-MAPK signaling pathway. Noonan-like syndrome with loose anagen hair (NSLH, including NSLH1, OMIM #607721 and NSLH2, OMIM #617506) is characterized by typical features of NS with additional findings of macrocephaly, loose anagen hair, growth hormone deficiency in some, and a higher incidence of intellectual disability. All NSLH1 reported cases to date have had an SHOC2 c.4A>G, p.Ser2Gly mutation; NSLH2 cases have been reported with a PPP1CB c.146G>C, p.Pro49Arg mutation, or c.166G>C, p.Ala56Pro mutation. True cleft palate does not appear to have been previously reported in individuals with NS or with NSLH. While some patients with NS have had growth hormone deficiency (GHD), other endocrine abnormalities are only rarely documented. We present a female patient with NSLH1 who was born with a posterior cleft palate, micrognathia, and mild hypotonia. Other findings in her childhood and young adulthood years include hearing loss, strabismus, and hypopituitarism with growth hormone, thyroid stimulating hormone (TSH), and gonadotropin deficiencies. The SHOC2 mutation may be responsible for this patient's additional features of cleft palate and hypopituitarism.

Moyamoya syndrome in a patient with Noonan-like syndrome with loose anagen hair

BACKGROUND

Noonan-like syndrome with loose anagen hair is one of the RASopathies characterized by Noonan syndrome-like features with unique ectodermal abnormalities. This syndrome is caused by mutations in the SHOC2 gene. We encountered a patient with moyamoya syndrome associated with Noonan-like syndrome with loose anagen hair presenting with transient ischemic attacks.

PATIENT DESCRIPTION

A 6-year-old girl was diagnosed with Noonan-like syndrome with loose anagen hair because of profound short stature and ectodermal anomalies such as sparse and easily pluckable hair. A heterozygous mutation of c.4A>G (p.S2G) in the SHOC2 gene was identified, and recombinant human growth hormone therapy was initiated at 8 years of age. At age 10, she manifested recurrent left hemiplegia. Moreover, cerebrovascular imaging revealed occlusion or narrowing of both internal carotid arteries and both middle cerebral arteries with distal moyamoya-like vessels. She is treated with aspirin and calcium channel blocker.

CONCLUSIONS

We describe the first case of Noonan-like syndrome with loose anagen hair associated with moyamoya syndrome, although it has been reported to be associated with a few cases of other RASopathies, including Noonan, cardiofaciocutaneous, and Costello syndromes. This report emphasizes the associations between cerebrovascular anomalies and Noonan-like syndrome with loose anagen hair.

Behavioral profile in RASopathies

Here, we describe neurobehavioral features in patients with RASopathies (i.e., Noonan syndrome, LEOPARD syndrome, Costello syndrome, and cardiofaciocutaneous syndrome), developmental disorders caused by mutations in genes coding transducers participating in the RAS-MAPK signaling cascade. Parents of 70 individuals with a RASopathy were asked to fill out the following questionnaires: Child Behavior Checklist (CBCL), Social Communication Questionnaire version lifetime (SCQ-L), and Modified Checklist for Autism in toddlers (M-CHAT). Data analysis indicated high rates of internalizing (37%) and externalizing problems (31%) on CBCL. Scores over the cut-off were documented in 64% of patients with cardiofaciocutaneous syndrome, 44% with Costello syndrome, and 12% with Noonan syndrome on SCQ-L/M-CHAT. Our findings indicate that mutations promoting dysregulation of the RAS-MAPK cascade mark an increased psychopathological risk and highlight that autistic-like behavior could be underdiagnosed in patients with RASopathies.