To describe the chromosomal alterations found in peripheral blood karyotypes performed at the Genetics and Genomics Laboratory of the Hospital del Niño of Panama, Dr. José Renán Esquivel, during the years 2015 to 2019. A descriptive, cross-sectional study with a quantitative approach was conducted. During this period, a total of 835 chromosomal analyses were performed on peripheral blood lymphocytes. Of these, 336 patients presented some type of chromosomal alteration. Among them, 85% (285 patients) had numerical chromosomal alterations, while 15% (51 patients) had structural chromosomal alterations, with numerical alterations being the most frequent. Among numerical alterations, Trisomy 21 (Down Syndrome) was the most common, representing 85% of these cases. Other alterations included Turner Syndrome (5%), Trisomy 13 (4%), Trisomy 18 (3%), and less frequently, Klinefelter Syndrome and mosaicism cases (1%). Regarding structural chromosomal alterations, the most frequent were Robertsonian translocations (31%), followed by heterochromatin+ (20%), deletions (16%), and inversions (12%). Less common alterations included duplications, isochromosomes, additional material, insertions, and fragile sites. The findings of this study partially align with previous research conducted in Argentina (Aiassa and Gorlat, 2010) and Chile (Estay et al., 2007). These studies also reported a predominance of numerical alterations, particularly Trisomy 21. However, differences were observed in the frequency of structural alterations: deletions were more common in Argentina, whereas translocations were more frequent in Chile and Panama. Numerical chromosomal alterations, particularly Trisomy 21, were the most common in the studied population, highlighting the importance of early cytogenetic diagnosis in pediatric patients.
Sadith O. Aldrette C. (Thu,) studied this question.