FREQUENCY OF CLINICAL FEATURES AND CYTOGENETIC DEFECTS IN DOWN SYNDROME DIAGNOSED AT AFIP

Objective: To determine the frequency of clinical features and cytogenetic abnormalities in patients of down syndrome and correlation of cytogenetic abnormalities with clinical features. Study Design: Cross sectional study. Place and Duration of Study: Department of Haematology, Armed Forces Institute of Pathology, Rawalpindi, from Feb 2017 to Feb 2018. Methodology: Total 163 patients with clinical suspicion of Down syndrome were selected by non-probability convenient sampling and diagnosis was confirmed by conventional cytogenetic analysis using Giemsa trypsin banding technique. Clinical features were assessed and frequency of different cytogenetic abnormalities were noted. Results: Out of total 163 patients, 96 (59%) were male and 67 (41%) were female. Median age of the patients was 11 months. Trisomy 21 was detected in 158 (96.9%), Robertsonian translocation in 4 (2.4%) and mosaicism in 01 (0.6%) patient. The predominant clinical features observed were slaunted with eyes, epicanthic folds, depressed nasal bridge and protruding tongue. Conclusion: Trisomy 21 is the most common cytogenetic abnormality observed in patients of down syndrome.