Webbed neck

Abstract: The triad, infantilism, webbing of the skin of the neck, and deformity of the elbow (cubitus valgus), occurring in the same individual is unusual, and, to my knowledge, has not been previously reported. It is sufficiently interesting to warrant this report, although the individual signs are perhaps not uncommon. Short neck, due to absence of the cervical spine, was first described by Klippel and Feil (1) in 1912. Only about 40 such cases have been reported to date, and these mostly in the French and German literature. A similar condition (pseudo-Klippel-Feil syndrome) (2) has been reported, in which there was a numerical variation in, and more or less complete fusion of, the cervical vertebrae. Webbing of the neck was first described by Kobylinski (3) in 1882, and its relation to congenital short neck was suggested by Darchter (4) in 1922.

Abstract: Two cases of Noonan syndrome are observed. The Noonan syndrome is a Turner-like syndrome with normal chromosomal constitution. Essential criteria in diagnosing the syndrome are the facial expression (hyper-telorisme, low-set and malformed ears, micrognathie, fish-like mouth). The short webbed neck and the cubitus valgus. These children are rather small and mental retardation can be present, especially in comparison with their siblings. Associated cardiac malformations occur in approximately 50% of the cases. We insist on audiologic findings. One case has a hearing impairment due to a malformation of the middle ear, recognised radiologically. The other has a deafness of perception type. Yet, the familial occurrence of last patient makes it doubtful whether this hearing loss can be linked to the Noonan-syndrome.

Abstract: ▪ Abstract Noonan syndrome is a pleiomorphic autosomal dominant disorder with short stature, facial dysmorphia, webbed neck, and heart defects. In the past decade, progress has been made in elucidating the pathogenesis of this disorder using a positional cloning approach. Noonan syndrome is now known to be a genetically heterogeneous disorder with nearly one half of cases caused by gain-of-function mutations in PTPN11, the gene encoding the protein tyrosine phosphatase SHP-2. Similar germ line mutations cause two related genetic disorders, Noonan-like disorder with multiple giant cell lesion syndrome and LEOPARD syndrome, and somatic PTPN11 mutations can underlie certain pediatric hematopoietic malignancies, including juvenile myelomonocytic, acute lymphoblastic, and acute myelogenous leukemias. A mouse model of PTPN11-related Noonan syndrome was recently generated, providing a reagent for studying disease pathogenesis in greater depth as well as experimenting with novel therapeutic strategies.

Abstract: Noonan Syndrome (NS) is characterised by short stature, typical facial dysmorphology and congenital heart defects. The incidence of NS is estimated to be between 1:1000 and 1:2500 live births. The main facial features of NS are hypertelorism with down-slanting palpebral fissures, ptosis and low-set posteriorly rotated ears with a thickened helix. The cardiovascular defects most commonly associated with this condition are pulmonary stenosis and hypertrophic cardiomyopathy. Other associated features are webbed neck, chest deformity, mild intellectual deficit, cryptorchidism, poor feeding in infancy, bleeding tendency and lymphatic dysplasias. The syndrome is transmitted as an autosomal dominant trait. In approximately 50% of cases, the disease is caused by missense mutations in the PTPN11 gene on chromosome 12, resulting in a gain of function of the non-receptor protein tyrosine phosphatase SHP-2 protein. Recently, mutations in the KRAS gene have been identified in a small proportion of patients with NS. A DNA test for mutation analysis can be carried out on blood, chorionic villi and amniotic fluid samples. NS should be considered in all foetuses with polyhydramnion, pleural effusions, oedema and increased nuchal fluid with a normal karyotype. With special care and counselling, the majority of children with NS will grow up and function normally in the adult world. Management should address feeding problems in early childhood, evaluation of cardiac function and assessment of growth and motor development. Physiotherapy and/or speech therapy should be offered if indicated. A complete eye examination and hearing evaluation should be performed during the first few years of schooling. Preoperative coagulation studies are indicated. Signs and symptoms lessen with age and most adults with NS do not require special medical care.