pulmonic stenosis

Arthrogryposis, Perthes Disease, and Upward Gaze Palsy

Clinical Characteristics
Ocular Features: 

Upward gaze is restricted and attempts to do so are associated with exotropia.

Systemic Features: 

Arthrogryposis with restricted joint mobility is present in both proximal and distal joints, including hips, elbows, hands, and knees.  It is usually evident early in infancy when parents note "tight joints".  Other joint deformities present to some degree are "trigger finger" deformities found in the middle fingers and thumbs.  Hip pain and difficulty walking as early as 3 years of age can be signs of avascular necrosis of the femoral head (Perthes disease).   

Pyloric stenosis can lead to severe, recurrent vomiting.  Pulmonic stenosis is commonly present and there are often cardiac septal defects as well as valvular malfunctions.  Bronchial asthma is a feature.

Genetics

One extended consanguineous Saudi family with three affected females has been reported.  No similar findings are present in the parents and the condition is most likely transmitted as an autosomal recessive.  A homozygous mutation in NEK9 (14q24) has been associated with this condition.

Heterozygous mutations in the same gene have been identified in 3 patients with nevus comedonicus (617025).  

Pedigree: 
Autosomal recessive
Treatment
Treatment Options: 

Flexion deformities may be at least partially alleviated by surgery and is especially beneficial for digital function.  Pyloric stenosis and cardiac valve disease may respond to surgery.

References
Article Title: 

Mutations in NEK9 Cause Nevus Comedonicus

Levinsohn JL, Sugarman JL; Yale Center for Mendelian Genomics, McNiff JM, Antaya RJ, Choate KA. Somatic Mutations in NEK9 Cause Nevus Comedonicus. Am J Hum Genet. 2016 May 5;98(5):1030-7.

PubMed ID: 
27153399

Accelerating matchmaking of novel dysmorphology syndromes through clinical and genomic characterization of a large cohort

Shaheen R, Patel N, Shamseldin H, Alzahrani F, Al-Yamany R, ALMoisheer A, Ewida N, Anazi S, Alnemer M, Elsheikh M, Alfaleh K, Alshammari M, Alhashem A, Alangari AA, Salih MA, Kircher M, Daza RM, Ibrahim N, Wakil SM, Alaqeel A, Altowaijri I, Shendure J, Al-Habib A, Faqieh E, Alkuraya FS. Accelerating matchmaking of novel dysmorphology syndromes through clinical and genomic characterization of a large cohort. Genet Med. 2016 Jul;18(7):686-95.

PubMed ID: 
26633546

Watson Syndrome

Clinical Characteristics
Ocular Features: 

Iris nodules similar to those seen in neurofibromatosis are found in some but not all patients with Watson syndrome.

Systemic Features: 

Short stature and low normal intelligence are the most consistent features.  Pulmonic stenosis and cafe-au-lait spots are also common.   The macrocephaly is relative and not striking.  Neurofibromas have been seen in a minority of patients.

Genetics

Mutations in the NF1(17q11.2) gene have been identified in members of several large pedigrees with an apparent autosomal dominant pattern.

It remains uncertain if this condition is allelic to neurofibromatosis I(162200) or if Watson syndrome is the result of mutations in contiguous genes.

The LEOPARD syndrome(151100) shares some clinical similarities such as short stature, pulmonic stenosis, cognitive deficits and cafe-au-lait spots but is caused by mutations in PTPN11.   The phenotype also resembles Noonan syndrome in some aspects.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

There is no known treatment for this condition but multidisciplinary management is recommended for isolated problems.

References
Article Title: 

Watson syndrome: is it a subtype of type 1 neurofibromatosis

Allanson JE, Upadhyaya M, Watson GH, Partington M, MacKenzie A, Lahey D, MacLeod H, Sarfarazi M, Broadhead W, Harper PS, et al. Watson syndrome: is it a subtype of type 1 neurofibromatosis? J Med Genet. 1991 Nov;28(11):752-6.

PubMed ID: 
1770531

LEOPARD Syndrome

Clinical Characteristics
Ocular Features: 

Ocular hypertelorism is a characteristic of all forms of the LEOPARD syndrome.  The lid fissures may be downward slanting.  Combined with the inverted triangle facies, the appearance is similar to that of the Noonan syndrome (163950).

Systemic Features: 

This is a multisystem disorder manifest in skin, heart, skeletal, genital, neurologic and auditory systems.  Generalized lentiginosis is characteristic but they may not be present until age 4 or 5 years following the appearance of cafe-au-lait spots.  Some patients have patchy scalp hair loss.  The facies bears some resemblance to the Noonan syndrome but usually without the short, webbed neck.  Sensorineural hearing loss is found in 20% of individuals.  Cardiac conduction defects, pulmonic stenosis, and hypertrophic cardiomyopathy are often (85%) present.  Cognitive defects are present in 30% of patients and some individuals have been described as mentally retarded.  Juvenile behavior may be evident in the presence of normal intelligence.  Hypospadias, cryptorchidism, and gonadal infantilism have been seen in some patients.  The ears are often malformed (87%).  Thoracic skeletal anomalies have been described in 75% of patients.  Although somatic growth is described as slow, short stature is present in less than half of patients.

Rare patients without lentigines are said to resemble the Noonan syndrome (163950) in appearance.

Genetics

Heterozygous mutations in the PTPN11 gene (12q24) are most frequently responsible for this autosomal dominant disorder.  The same gene is mutated in more than half of patients with the Noonan syndrome (NS1)(163950) with which it is allelic.  Other mutations that cause what is called LEOPARD syndrome are RAF1 and BRAF.

Other types of LEOPARD syndrome such as LEOPARD syndrome 2 (611554) are far more rare but also share mutations with Noonan syndrome (RAF1 mutations in Noonan syndrome 5) (611553) and LEOPARD syndrome 3 (613707) with mutations in BRAF similar to that seen in NS7 (613706).

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Assistive hearing devices, especially cochlear implants, may be helpful.  Special education can be of value in more mildly affected individuals.Treatment of cryptorchidism is similar to that of other children.

References
Article Title: 
Subscribe to RSS - pulmonic stenosis