This clinic is for children and young people who have 22q11 deletion syndrome and their families. The role of the clinic is to bring together affected children, families with a specialist multi-disciplinary team to help coordinate and guide care of these patients across Wales. For effective care, local community services are essential, and early involvement of a community paediatrician is strongly encouraged. The following content is intended as an aid to healthcare workers involved in the care of patients with this common condition, and gratefully acknowledges the Max Appeal consensus document from clinicians’ relevant summaries on 22q11 deletion syndrome as a key source.
When referring a patient to the 22q11 deletion syndrome MDT clinic, please consider including the information in the following document:
In 1965, ‘DiGeorge Syndrome’ was first described as a triad of cardiac defects, hypocalcaemia and immunodeficiency (1, 2). In the 1990s, fluorescence in situ hybridization identified a deletion at band 11.2 on the long arm of chromosome 22 as the cause of this and overlapping syndromes, such as velo-cardio-facial syndrome, DiGeorge Syndrome and Shprintzen syndrome (3). Now it is recognised the features are due to the same deletion, the syndrome is classified as the “22q11.2 deletion syndrome”.
Array comparative genomic hybridisation is now widely used in children with learning disabilities, providing more accurate information on 22q deletions and duplications. Children with subtle features are increasingly being tested, possibly leading to more 22q11 deletion syndrome diagnoses (4, 5, 6). It is the commonest deletion syndrome, with incidence estimates range from 1/1000 - 1/6000 births, with the most common being 1/4000 (1-4, 7-8).
Inheritance follows an autosomal dominant fashion. However, approximately 90% of cases are spontaneous mutations (1, 3). It is recommended that parental chromosomes are checked as they may have undiagnosed 22q11.2 deletion syndrome, being asymptomatic or having mild features. Parents may wish to use prenatal testing on future pregnancies (1, 5, 9). The heterogeneity of 22q11.2 deletion syndrome results in diverse presentations, both in type and severity of difficulties and the age at which they develop, meaning children present to a number of different specialities. Not every child is severely affected, and many will grow up to have a normal life expectancy (1, 6, 8). Some of the core features are shown in the diagram below.
Max Appeal is a registered charity, offering support to those affected by 22q11 Deletion Syndrome, their families, carers and friends. They can offer a listening ear, useful literature and help in finding further information. Where possible, a representative of the charity will also be available on the day of the MDT clinic.
Contact Details: www.maxappeal.org.uk
Please see referral information document above.
There is increasing recognition of the importance of mental health. Consider Child and Adolescent Mental Health Services referral for assessment if autistic-spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD) and behavioural issues in the preschool and school age child cause dysfunction.
1. McDonald-McGinn DM, Sullivan KE, Marino B, Philip N, Swillen A, Vorstman JAS, et al. 22q11.2 deletion syndrome. Nat Rev Dis Primers. 2015;1:15071. doi:10.1038/nrdp.2015.71
2. Max Appeal. A Bit of Background History. [accessed 25 Mar 2018]. Available from: http://www.maxappeal.org.uk/knowledge/a_bit_of_background_history
3. The International 22q11.2 Foundation Incorporated. 22q11.2 Deletion. 2018 [accessed 24 Mar 2018]. Available from: http://www.22q.org/about-22q/faqs/22q11-2-deletion/#1
4. Bassett A, McDonald-McGinn D, Devriendt K, Digilio M, Goldenberg P, Habel A, et al. Practical Guidelines for Managing Patients with 22q11.2 Deletion Syndrome. J Pediatr. 2011; 159(2):332-339. doi:10.1016/j.peds.2011.02.039
5. Wentzel C, Fernström M, Ohrner Y, Annerén G, Thuresson AC. Clinical variability of the 22q11.2 duplication syndrome. Eur J Med Genet. 2008;51(6):501-510. doi:10.1016/J.ejmg.2008.07.005
6. Habel A, Herriot R, Kumararatne D, Allgrove J, Baker K, Baxendale H, et al. Towards a safety net for management of 22q11.2 deletion syndrome: guidelines for our times. Eur J Pediatr. 2014;173(6):757-765. doi:10.1007/s00431-013-2240-z
7. Fung WL, Butcher NJ, Costain G, Andrade DM, Boot E, Chow EWC, et al. Practical guidelines for managing adults with 22q11.2 deletion syndrome. Genet Med. 2015;17(8):599-609. doi:10.1038/gim.2014.175
8. Oskarsdóttir S, Vujic M, Fasth A. Incidence and prevalence of the 22q11 deletion syndrome: a population-based study in Western Sweden. Arch Dis Child. 2004;89(2):148-151