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Cardiology in the Young Nov 2023Myhre syndrome is a rare disease secondary to pathogenic variants in gene. It is a multisystem disease characterised by short stature, deafness, joint stiffness,...
Myhre syndrome is a rare disease secondary to pathogenic variants in gene. It is a multisystem disease characterised by short stature, deafness, joint stiffness, craniofacial dysmorphism, and potential cardiac manifestations. Herein, we report two new paediatric cases of Myhre syndrome who, additionally, presented with mid-aortic syndrome. This confirms and extends the scarce reports describing the association between these two entities.
Topics: Male; Humans; Child; Mutation; Intellectual Disability; Growth Disorders; Hand Deformities, Congenital
PubMed: 37325812
DOI: 10.1017/S1047951123001592 -
Journal of Clinical Medicine Jul 2023Disorders of immunity are poorly recognised in some rare multisystem genetic conditions. We aim to describe syndromic features and immunological defects in children with...
BACKGROUND
Disorders of immunity are poorly recognised in some rare multisystem genetic conditions. We aim to describe syndromic features and immunological defects in children with syndromic primary immunodeficiencies (sPIDs).
METHODS
This is a retrospective descriptive study of children aged 0-18 years with sPIDs under the care of the paediatric immunology service at the Bristol Royal Hospital for Children, United Kingdom, from January 2006 to September 2021.
RESULTS
sPIDs were identified in 36 patients. Genetic diagnoses which are not commonly associated with PIDs and not included in the International Union of Immunological Societies classification were present in 7/36 (19%): Trisomy 22, Arboleda-Tham syndrome, 2p16.3 deletion syndrome, supernumerary ring chromosome 20 syndrome, Myhre syndrome, Noonan syndrome, and trichothiodystrophy/Cockayne syndrome complex. Recurrent and/or severe infections were the most common clinical features (n = 33, 92%). Approximately half had combined immunodeficiency or antibody deficiency. The most common extra-immunological manifestations include dysmorphism (72%), disorders of nervous (78%), musculoskeletal (69%), haematology/lymphatic (58%), and gastrointestinal, hepatic/pancreatic (58%) systems.
CONCLUSIONS
Patients with sPIDs often have multiorgan involvement and some are non-immunologically mediated. There should be a low threshold to clinically assess and investigate for disorders of immunity in any patients with syndromic features especially when they present with recurrent/severe/opportunistic infections, features of immune dysregulation, autoinflammation or lymphoproliferation.
PubMed: 37568366
DOI: 10.3390/jcm12154964 -
Hereditary Cancer in Clinical Practice Dec 2023Juvenile polyposis syndrome (JPS), a rare autosomal dominant syndrome, affects one per 100 000 births, increasing lifetime cancer risk by 9 - 50%. Around 40-60% of JPS... (Review)
Review
BACKGROUND
Juvenile polyposis syndrome (JPS), a rare autosomal dominant syndrome, affects one per 100 000 births, increasing lifetime cancer risk by 9 - 50%. Around 40-60% of JPS cases are caused by disease-causing variants (DCV) in SMAD4 or BMPR1A genes, of which SMAD4 accounts for 20-30%.
OBJECTIVES
To characterise genotype-phenotype correlations between sites and types of variants within SMAD4 to JPS phenotypes, to inform diagnosis, screening, and management of JPS.
SEARCH METHODS
Online search databases utilised included Ovid MEDLINE, Embase Classic + Embase and PubMed, using search terms classified by MeSH on Demand. Adjacency operators, word truncation and Boolean operators were employed. 110 articles were included in the review, collating 291 variants from the literature.
RESULTS
In SMAD4 + JPS patients, most variants are located around SMAD4's MH2 domain (3' end). Extracolonic involvement, massive gastric polyposis and a more aggressive phenotype have been associated with SMAD4 + JPS, predisposing to gastric cancer. This has contributed to an overall higher incidence of GI cancers compared to other genes causing JPS, with DCVs mostly all within the MH2 domain. Genetically related allelic disorders of SMAD4 also have variants in this region, including hereditary haemorrhagic telangiectasia (HHT) alongside SMAD4 + JPS, and Myhre syndrome, independent of JPS. Similarly, with DCVs in the MH2 domain, Ménétrier's disease, hypertrophic osteoarthropathy and juvenile idiopathic arthritis have been seen in this population, whereas cardiac pathologies have occurred both alongside and independently of SMAD4 + JPS with DCVs in the MH1 domain.
CONCLUSION
Truncating and missense variants around the MH2 region of SMAD4 are most prevalent and pathogenic, thus should undergo careful surveillance. Given association with extracolonic polyposis and higher GI cancer risk, endoscopic screening should occur more frequently and at an earlier age in SMAD4 + JPS patients than in patients with other causative genes, with consideration of Ménétrier's disease on upper GI endoscopy. In addition, HHT should be evaluated within 6 months of diagnosis, alongside targeted clinical examination for extraintestinal manifestations associated with SMAD4 + JPS. This review may help modify clinical diagnosis and management of SMAD4 + JPS patients, and aid pathogenicity classification for SMAD4 DCVs through a better understanding of the phenotypes.
PubMed: 38066625
DOI: 10.1186/s13053-023-00267-z -
American Journal of Medical Genetics.... May 2024Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty...
Myhre syndrome is an increasingly diagnosed ultrarare condition caused by recurrent germline autosomal dominant de novo variants in SMAD4. Detailed multispecialty evaluations performed at the Massachusetts General Hospital (MGH) Myhre Syndrome Clinic (2016-2023) and by collaborating specialists have facilitated deep phenotyping, genotyping and natural history analysis. Of 47 patients (four previously reported), most (81%) patients returned to MGH at least once. For patients followed for at least 5 years, symptom progression was observed in all. 55% were female and 9% were older than 18 years at diagnosis. Pathogenic variants in SMAD4 involved protein residues p.Ile500Val (49%), p.Ile500Thr (11%), p.Ile500Leu (2%), and p.Arg496Cys (38%). Individuals with the SMAD4 variant p.Arg496Cys were less likely to have hearing loss, growth restriction, and aortic hypoplasia than the other variant groups. Those with the p.Ile500Thr variant had moderate/severe aortic hypoplasia in three patients (60%), however, the small number (n = 5) prevented statistical comparison with the other variants. Two deaths reported in this cohort involved complex cardiovascular disease and airway stenosis, respectively. We provide a foundation for ongoing natural history studies and emphasize the need for evidence-based guidelines in anticipation of disease-specific therapies.
PubMed: 38779990
DOI: 10.1002/ajmg.a.63638 -
Indian Journal of Psychiatry Oct 2023
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Prenatal Diagnosis Sep 2023Prenatal testing was performed in a 39-year-old Chinese pregnant woman referred for increased nuchal translucency measuring 5.7 mm. Non-invasive prenatal testing and...
Prenatal testing was performed in a 39-year-old Chinese pregnant woman referred for increased nuchal translucency measuring 5.7 mm. Non-invasive prenatal testing and SNP array study on amniotic fluid samples were normal. Whole exome sequencing (WES) was initiated further as the fetus had pericardial effusion of 1.2 mm, thickened myocardium over the right ventricular lateral wall and aberrant right subclavian artery. A detailed fetal echocardiogram also revealed persistent left superior vena cava and dilated coronary sinus at 20 weeks. From whole exome sequencing of the trio, a de novo heterozygous variant NM_005359.5(SMAD4): c.1499T>C (p.Ile500Thr) was detected. This pathogenic variant has been reported in the postnatal case cohort of Myhre syndrome. This condition is characterized by facial dysmorphism, intellectual disability, hearing loss, skeletal abnormalities and potential life threatening respiratory or cardiovascular manifestations. Termination of pregnancy was performed at 23 weeks. Small chins, pre-axial polydactyly, brachydactyly and clinodactyly were noted in the abortus. Ultrasound findings of increased nuchal translucency, thickened myocardium and pericardial effusion prompted further genetic evaluation for the prenatal diagnosis of Myhre syndrome by whole exome sequencing.
Topics: Pregnancy; Female; Humans; Adult; Intellectual Disability; Nuchal Translucency Measurement; Pericardial Effusion; Vena Cava, Superior; Prenatal Diagnosis; Heart Defects, Congenital; Ultrasonography, Prenatal; Smad4 Protein
PubMed: 37529930
DOI: 10.1002/pd.6414 -
Ear, Nose, & Throat Journal Jun 2024Myhre syndrome (MS) is a rare genetic condition that presents with multiple genetic anomalies including cleft lip and palate and Eustachian tube dysfunction. These...
Myhre syndrome (MS) is a rare genetic condition that presents with multiple genetic anomalies including cleft lip and palate and Eustachian tube dysfunction. These patients are at a high risk for airway scarring from intubation and mucosal inflammation. Hearing loss (conductive or mixed, of varying severity) is a common comorbidity in these patients, the exact etiology of which is still unclear. We present the cases of 2 unrelated children with MS who suffered progressive mixed hearing loss from fibrosis and obliteration of the middle ear spaces. Both patients had multiple sets of ear tubes that demonstrated early extrusion. The older patient underwent bone conduction implantation at age 11 which resulted in dramatic improvement of speech recognition and interactive skills. The other younger patient demonstrates a similar trajectory but has not yet undergone implantation. Otolaryngologists should take a cautious approach to surgery of the eardrum and middle ear to avoid unnecessary induction of fibrosis in this susceptible patient population. These cases highlight a newly described etiology for hearing loss and suggest a benefit to bone conduction implantation.
PubMed: 38907583
DOI: 10.1177/01455613241256474 -
American Journal of Medical Genetics.... Jun 2024
PubMed: 38239053
DOI: 10.1002/ajmg.a.63497