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Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
[Down Syndrome--a clinical, cytogenetic and epidemiologic analysis of 165 patients]
1Centro de Genética, Instituto Fernandes Figueira, Fundação Oswaldo Cruz, Ministério da Saúde, Rio de Janeiro, RJ, Brazil.
Abstract:
A clinical follow up of 165 Down Syndrome (DS) patients in an outpatient clinic programme at the Centro de Genética Médica (IFF - FIOCRUZ) was undertaken retrospectively. Clinical and laboratorial investigations were performed, such as cytogenetics and hematological analysis, thyroid hormones survey, abdominal ultrasound and cervical column X Rays. The clinical diagnosis of Down Syndrome was mostly performed during the first year of life, and 70% of all patients were under 4 years of age, being predominantly males. Trisomy 21 derived from non disjunction was found in 85% of the patients. The most common congenital malformation was cardiopathy (37.5%) and among all the clinical complications, repeated pneumonia could be evidenced in 30% of the patients, mainly during the first year of life. Leukopenia was observed in 14% of the patients and abdominal ultrasound scans allowed the early detection of biliary stones in 4.3% of the patients examined, a significative finding in the paediatric population. A prospective clinical programme aiming to anticipate the detection of clinical complications on at risk DS populations will fulfill its objectives and may act as a reducing factor in the infantile mortality rate.
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