Circulating Blasts and Associated Hematologic Disorders in Neonates with Down Syndrome

Abstract

We analyzed complete blood count (CBC) data obtained from neonates with Down syndrome (DS) in a primarily Hispanic population over a 10-year period to determine the incidence of hematologic abnormalities and the relationship of abnormalities to the presence of circulating blasts (CB). Hematologic values obtained during the first 10 days were analyzed. Definitions were: CB, ≥ 1% blasts manually counted on peripheral smear; elevated white blood cell count (WBC), >30,000 cells/mm(3); thrombocytopenia, platelet count < 150,000/mm(3); polycythemia, hematocrit >65%. Two hundred thirty-two neonates (88% Hispanic) with DS had 692 CBCs available for analysis. The presence of CB (11.6%) and the incidence of thrombocytopenia (60.2%) were significantly higher in DS neonates than in the reference group. Elevated WBC (33.3%) and thrombocytopenia (84.6%) were more common in DS neonates with CB versus those with no CB. No relationship between thrombocytopenia and polycythemia was observed. Unlike previous reports, we did not observe a male predominance in those DS neonates with CB. Thrombocytopenia occurred frequently in DS neonates and was significantly more likely in those with CB than in those with no CB. CBC screening should be performed routinely in DS neonates.

Descriptive study of the complete blood count in newborn infants with Down syndrome

“…This confirms the importance of obtaining a CBC during the first days of life in all infants with DS, as recommended by the American Academy of Pediatrics Committee on Genetics [Bull and Committee on Genetics, ]. The hematological findings in newborns with DS in previous studies [Miller and Cosgriff, ; Henry et al, ; Kim et al, ; Jackson et al, ], compared to our findings are summarized in Table : Red blood cells : (i) Polycythemia ranged in frequency from 10.8% to 34.4% depending the definition used (generally hematocrit ≥65%). Using this definition, the frequency of polycythemia in our study was markedly lower than other studies (Table ).…”

“…Abnormal values of MCV, MCH concentration (MCHC, g/L), RDW, WBC (10 3 /µl), and basophils (10 3 /µl) were defined according the postnatal day of life using their respective reference ranges or intervals [Matoth et al, ; De Alarcón and Werner, ; Christensen et al, ]. We also used the following operational definitions [Henry et al, ; Kim et al, ; Jackson et al, ; Henry and Christensen, ]: polycythemia—hematocrit ≥65%; anemia—low hemoglobin and/or hematocrit; macrocytosis—high MCV; microcytosis—low MCV; anisocytosis (red blood cells of unequal size)—high RDW; thrombocytopenia—platelet count (<150 × 10 3 /µl) divided into mild (100–149 × 10 3 /µl), moderate (50 to <100 × 10 3 /µl), and severe (< 50 × 10 3 /µl); thrombocytosis—high platelet count, and elevated WBC count ( ≥ 30 × 10 3 /µl).…”

“…In previous studies, at least one abnormality in one or more of the hematopoietic cell lines evaluated by the CBC has been observed in approximately half of all infants [Miller and Cosgriff, ]. Hematological anomalies most frequently reported in newborns and infants with DS include polycythemia, thrombocytopenia, neutrophilia, elevated white blood cell (WBC) count, and the presence of peripheral circulating blasts [Weinberger and Oleinick, ; Miller and Cosgriff, ; Starc, ; Hord et al, ; Kivivuori et al, ; Massey, ; Henry et al, ; Kim et al, ; Jackson et al, ]. On the other hand, thrombocytosis, anemia, macrocytosis, and neutropenia are rarely seen in neonates with DS [Ibarra et al, ; Starc, ; Henry et al, ; Kim et al, ].…”

“…The usefulness of the CBC during the first week of life in infants with DS has been recognized; however, studies are limited and have evaluated only some of its parameters [Miller and Cosgriff, ; Henry et al, ; Kim et al, ; Jackson et al, ]. In addition, most of these studies do not include a reference group, with the exception of the Jackson et al [] study.…”

“…The usefulness of the CBC during the first week of life in infants with DS has been recognized; however, studies are limited and have evaluated only some of its parameters [Miller and Cosgriff, ; Henry et al, ; Kim et al, ; Jackson et al, ]. In addition, most of these studies do not include a reference group, with the exception of the Jackson et al [] study. Comparing the results from these studies is difficult because of differences in operative definitions and the diversity of reference ranges used to interpret the different CBC parameters [Matoth et al, ; Manroe et al, ; Mouzinho et al, ; Christensen, ; De Alarcón and Werner, ; Joplin et al, ].…”