How Much do we Know About the Findings of 22q11.2 Deletion Syndrome?: A Single-Centre Study with 11-Year Follow-Up

Abstract

Purpose: 22q11.2 deletion syndrome is a contiguous gene deletion syndrome with multisystem involvement characterized by cardiac defects, immunodeficiency and hypocalcemia. Variable expression and a wide range of clinical findings make it difficult for clinicians to decide on the test. Methods: Evaluation was made of the clinical findings of patients who underwent the FISH test for 22q11.2 deletion syndrome between 2006 and 2017. Results: Of the 180 patients, 152 84.45% had cardiac defects, 5 2.78% had immune defects, 132 73.4% had dysmorphic findings and 52 28.89% had growth / developmental delay. Ten patients had 22q11.2 deletion syndrome 5.56% and 9 of these had cardiac defects. Hypocalcemia was present in 5 50% patients and only one patient had immunodeficiency. Conclusion: In this study, the accuracy of the indication was evaluated retrospectively based on the clinical findings of patients who underwent FISH analysis for 22q11.2 deletion syndrome. In cases with congenital cardiac defects, although 22q11.2 deletion syndrome is one of the possible diagnoses of the clinician, a detailed examination of the defect type before testing will increase the diagnosis rate. It should be kept in mind that this syndrome should be considered in the presence of major findings such as immunodeficiency or hypocalcemia

Keywords

• 22q11.2 deletion syndrome, congenital cardiac defect, immunodeficiency, hypocalcemia

References

1. 1. DiGeorge AM. Congenital absence of the thymus and its immunologic consequences: concurrence with congenital hypoparathyroidism. In: Birth defects: immunologic deficiency diseases in man. 4. National Foundation–March of Dimes, White Plains (NY); 1968:116 (Original Article Series, vol. IV:116-21).
2. 2. McDonald-McGinn DM EB, Zackai EH. 22q11.2 Deletion Syndrome 1999. 1993–2019. In: GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle.
3. 3. Wilson DI, Cross IE, Goodship JA, et al. A prospective cytogenetic study of 36 cases of DiGeorge syndrome. Am J Hum Genet 1992;51:957– 963. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1682842/
4. 4. McDonald-McGinn DM, Sullivan KE. Chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome). Medicine (Baltimore) 2011;90:1–18. [CrossRef]
5. 5. McDonald-McGinn DM, Sullivan KE, Marino B, et al. 22q11.2 deletion syndrome. Nat Rev Dis Primers 2015;1:15071. [CrossRef]
6. 6. Kobrynski LJ, Sullivan KE. Velocardiofacial syndrome, DiGeorge syndrome: the chromosome 22q11.2 deletion syndromes. Lancet 2007;370:1443–1452. [CrossRef]
7. 7. Shprintzen RJ. Velo-cardio-facial syndrome: 30 Years of study. Dev Disabil Res Rev 2008;14:3–10. [CrossRef]
8. 8. Fomin AB, Pastorino AC, Kim CA, Pereira CA, Carneiro-Sampaio M, Abe-Jacob CM. DiGeorge Syndrome: a not so rare disease. Clinics (Sao Paulo) 2010;65:865–869. [CrossRef]

9. 9. Goodship J, Cross I, LiLing J, Wren C. A population study of chromosome 22q11 deletions in infancy. Arch Dis Child 1998;79:348– 351. [CrossRef]
10. 10. Peyvandi S, Lupo PJ, Garbarini J, et al. 22q11.2 deletions in patients with conotruncal defects: data from 1,610 consecutive cases. Pediatr Cardiol 2013;34:1687–1694. [CrossRef]
11. 11. Morsheimer M, Brown Whitehorn TF, Heimall J, Sullivan KE. The immune deficiency of chromosome 22q11.2 deletion syndrome. Am J Med Genet A 2017;173:2366–2372. [CrossRef]
12. 12. Fujii S, Nakanishi T. Clinical manifestations and frequency of hypocalcemia in 22q11.2 deletion syndrome. Pediatr Int 2015;57:1086–1089. [CrossRef]
13. 13. Sgardioli IC, Monteiro FP, Fanti P, Paiva Vieira TP, Gil-da-Silva-Lopes VL. Testing criteria for 22q11.2 deletion syndrome: preliminary results of a low cost strategy for public health. Orphanet J Rare Dis 2019;14:123. [CrossRef]
14. 14. Bahamat AA, Assidi M, Lary SA, et al. Use of Array Comparative Genomic Hybridization for the Diagnosis of DiGeorge Syndrome in Saudi Arabian Population. Cytogenet Genome Res 2018;154:20–29. [CrossRef]
15. 15. Monteiro FP, Vieira TP, Sgardioli IC, et al. Defining new guidelines for screening the 22q11.2 deletion based on a clinical and dysmorphologic evaluation of 194 individuals and review of the literature. Eur J Pediatr 2013;172:927–945. [CrossRef]