megacolon

Mowat-Wilson Syndrome

Clinical Characteristics
Ocular Features: 

Most reports of Mowat-Wilson disorders provide only incomplete ocular findings and the full phenotype remains to be described.  Most of the reported findings are part of the facial phenotype, such as downward slanting palpebral fissures, and 'wedge-shaped' eyebrows with the medial portion visibly wider than the temporal region.  Hypertelorism, strabismus and telecanthus have also been noted.  However, optic nerve atrophyor aplasia, RPE atrophy, microphthalmia, ptosis, and cataracts are sometimes present while strabismus is more common.  Iris and other uveal colobomas may be present and at least one patient has been reported with retinal aplasia.  There may be considerable asymmetry in the features among the two eyes.

Systemic Features: 

This is a highly complex dysmorphic developmental disorder with unusual progression of facial features.  Birth weight and length are usually normal but later there is general somatic and mental growth delay with microcephaly (pre- and post natal), short stature, intellectual disability, and epilepsy (70%).  Hypotonia has been noted at birth.  A significant proportion (~50%) of patients have Hirschsprung disease with megacolon.  Congenital heart defects are common, many involving septal openings.  Hypospadias is often present with or without other genitourinary anomalies.  Teeth are often crowded and crooked.  The earlobes may be flattened and may have a central depression.

The facial features are present in early childhood but as they mature the upper half of the nasal profile becomes convex, while the nasal tip becomes longer and overhangs the philtrum.  The eyes appear more deeply set.  The chin lengthens and prognathism becomes apparent.  IQ levels cannot be determined but many individuals exhibit behavioral or emotional disturbances.

Genetics

Heterozygous mutations in ZEB2 (2q22.3) are responsible for most cases (81%) of this disorder.  A large number of molecular mutations, many of the nonsense type, have been reported. About 2-4% of patients have cytogenetic alterations involving the 2q22 region.

Another disorder with microcephaly, intellectual disability and Hirschsprung disease is Goldberg-Shprintzen syndrome (609460) with mutations in the KIAA1279 gene.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Treatment may be directed at specific defects but there is no treatment for the general disorder. Individuals can live to adulthood. Treatment is largely symptomatic.  Physical and speech treatment can be helpful if initiated early.

References
Article Title: 

Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and

Ivanovski I, Djuric O, Caraffi SG, Santodirocco D, Pollazzon M, Rosato S,
Cordelli DM, Abdalla E, Accorsi P, Adam MP, Ajmone PF, Badura-Stronka M, Baldo C,
Baldi M, Bayat A, Bigoni S, Bonvicini F, Breckpot J, Callewaert B, Cocchi G,
Cuturilo G, De Brasi D, Devriendt K, Dinulos MB, Hjortshoj TD, Epifanio R,
Faravelli F, Fiumara A, Formisano D, Giordano L, Grasso M, Gronborg S, Iodice A,
Iughetti L, Kuburovic V, Kutkowska-Kazmierczak A, Lacombe D, Lo Rizzo C, Luchetti
A, Malbora B, Mammi I, Mari F, Montorsi G, Moutton S, Moller RS, Muschke P,
Nielsen JEK, Obersztyn E, Pantaleoni C, Pellicciari A, Pisanti MA, Prpic I,
Poch-Olive ML, Raviglione F, Renieri A, Ricci E, Rivieri F, Santen GW, Savasta S,
Scarano G, Schanze I, Selicorni A, Silengo M, Smigiel R, Spaccini L, Sorge G,
Szczaluba K, Tarani L, Tone LG, Toutain A, Trimouille A, Valera ET, Vergano SS,
Zanotta N, Zenker M, Conidi A, Zollino M, Rauch A, Zweier C, Garavelli L.
Phenotype and genotype of 87 patients with Mowat-Wilson syndrome and
recommendations for care. Genet Med. 2018 Jan 4. doi: 10.1038/gim.2017.221. [Epub
ahead of print].

PubMed ID: 
29300384

Clinical spectrum of eye malformations in four patients with Mowat-Wilson syndrome

Bourchany A, Giurgea I, Thevenon J, Goldenberg A, Morin G, Bremond-Gignac D, Paillot C, Lafontaine PO, Thouvenin D, Massy J, Duncombe A, Thauvin-Robinet C, Masurel-Paulet A, Chehadeh SE, Huet F, Bron A, Creuzot-Garcher C, Lyonnet S, Faivre L. Clinical spectrum of eye malformations in four patients with Mowat-Wilson syndrome. Am J Med Genet A. 2015 Apr 21. [Epub ahead of print]

PubMed ID: 
25899569

The behavioral phenotype of Mowat-Wilson syndrome

Evans E, Einfeld S, Mowat D, Taffe J, Tonge B, Wilson M. The behavioral phenotype of Mowat-Wilson syndrome. Am J Med Genet A. 2012 Feb;158A(2):358-66. doi: 10.1002/ajmg.a.34405.

PubMed ID: 
22246645

Mowat-Wilson syndrome: facial phenotype changing with age: study of 19 Italian patients and review of the literature

Garavelli L, Zollino M, Mainardi PC, Gurrieri F, Rivieri F, Soli F, Verri R, Albertini E, Favaron E, Zignani M, Orteschi D, Bianchi P, Faravelli F, Forzano F, Seri M, Wischmeijer A, Turchetti D, Pompilii E, Gnoli M, Cocchi G, Mazzanti L, Bergamaschi R, De Brasi D, Sperandeo MP, Mari F, Uliana V, Mostardini R, Cecconi M, Grasso M, Sassi S, Sebastio G, Renieri A, Silengo M, Bernasconi S, Wakamatsu N, Neri G. Mowat-Wilson syndrome: facial phenotype changing with age: study of 19 Italian patients and review of the literature. Am J Med Genet A. 2009 Mar;149A(3):417-26. Review.

PubMed ID: 
19215041

Clinical and mutational spectrum of Mowat-Wilson syndrome

Zweier C, Thiel CT, Dufke A, Crow YJ, Meinecke P, Suri M, Ala-Mello S, Beemer F, Bernasconi S, Bianchi P, Bier A, Devriendt K, Dimitrov B, Firth H, Gallagher RC, Garavelli L, Gillessen-Kaesbach G, Hudgins L, K?SS?SSri?SSinen H, Karstens S, Krantz I, Mannhardt A, Medne L, M?ocke J, Kibaek M, Krogh LN, Peippo M, Rittinger O, Schulz S, Schelley SL, Temple IK, Dennis NR, Van der Knaap MS, Wheeler P, Yerushalmi B, Zenker M, Seidel H, Lachmeijer A, Prescott T, Kraus C, Lowry RB, Rauch A. Clinical and mutational spectrum of Mowat-Wilson syndrome. Eur J Med Genet. 2005 Apr-Jun;48(2):97-111

PubMed ID: 
16053902

Multiple Endocrine Neoplasia, Type IIB

Clinical Characteristics
Ocular Features: 

Corneal nerves are medullated and appear prominent.  Neuromas of the lid margins and sometimes the conjunctiva are common features.  Thickening of the entire eyelids may be present.

Systemic Features: 

Some manifestations may be seen in early childhood.  Prominent physical features include full lips, thickened eyelids, high arched palate and a marfanoid habitus.  Medullary carcinoma of the thyroid is almost always present and can be the cause of death in relatively young individuals. Metastases are usually to the regional lymph nodes or to liver, lungs, or bone. Pheochromocytomas and megacolon secondary to gastrointestinal neuromas are commonly seen.  The esophagus sometimes lacks normal motility for the same reason.  Neuromas often lead to thickening of the lips and tongue and can also appear as pedunculated nodules on these structures.  Cafe-au-lait spots and increased pigmentation of the hands, feet, and circumoral areas are frequently present.  Many patients have dysmorphic features suggestive of Marfan syndrome including a typical habitus, pectus excavatum, scoliosis, and pes cavus. Proximal myopathy and peripheral neuropathy are sometimes seen.

Another form of multiple endocrine neoplasia, called MEN2A, differs in the absence of mucosal neuromas and the marfanoid habitus.  MEN2A patients are more likely to have parathyroid hyperplasia.

Genetics

This is an autosomal dominant disorder caused by mutations in the tyrosine kinase domain of the RET gene (10q11.2). This disorder (MEN2B) may be allelic to MEN2A.  Perhaps half of MEN2B cases occur sporadically and in these the mutant RET allele is usually of paternal origin.

Pedigree: 
Autosomal dominant
Treatment
Treatment Options: 

Treatment of local lesions is sometimes indicated.  Biochemical testing for pheochromocytoma should be done before any surgery.

References
Article Title: 
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