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Hematologic abnormalities in children with Down syndrome
1Department of Pediatrics, University of Chicago Pritzker School of Medicine, Wyler Children's Hospital, La Rabida Children's Hospital and Research Center, Chicago, Illinois.
Insights
Children with Down syndrome (DS) often exhibit macrocytosis (high MCV) and leukopenia (low WBC counts). Folate levels did not explain these common hematologic findings in DS.
Area of Science:
- Pediatric Hematology
- Genetics
- Down Syndrome Research
Background:
- Down syndrome (DS) is associated with various health complications.
- Hematologic abnormalities are frequently observed in children with DS.
- Understanding these differences is crucial for comprehensive care.
Purpose of the Study:
- To compare hematologic parameters in children with and without Down syndrome.
- To investigate the prevalence of macrocytosis and leukopenia in young children with DS.
- To explore the potential role of folate deficiency in these hematologic findings.
Main Methods:
- A comparative study involving 18 children with DS and 18 age/gender-matched healthy controls (ages 2-6 years).
- Analysis of complete blood counts, including Mean Corpuscular Volume (MCV) and White Blood Cell (WBC) counts.
- Measurement of serum and red blood cell (RBC) folate concentrations.
Main Results:
- Children with DS showed significantly higher MCVs and hematocrits compared to controls.
- A higher percentage of children with DS had MCVs above the 97th percentile (66% vs. 11%).
- Children with DS had significantly lower WBC counts (33% below the 5th percentile vs. 6% in controls).
- No significant differences in serum or RBC folate levels were found between the groups.
Conclusions:
- Macrocytosis and leukopenia are common hematologic findings in children with Down syndrome.
- These abnormalities are not explained by folate deficiency.
- Further research may be needed to elucidate the underlying mechanisms of these hematologic changes in DS.
Abstract:
We compared the hematologic parameters of 18 otherwise healthy children with Down syndrome (DS) in the age range of 2-6 years to those of 18 healthy non-DS controls matched for age and gender. The children with DS had MCVs and hematocrits increased significantly compared to controls and decreased WBCs compared to controls; 66% of the children with DS compared to 11% of non-DS controls had MCVs greater than the 97th percentile for age (P < 0.0001); the mean MCVs were 86.9 and 80.6, respectively. Although hematocrits were within normal limits for age for all DS and non-DS subjects, the DS patients had significantly higher hematocrits (39.1% vs. 36.9%, P < 0.014). We also found that 33% of the children had WBCs < 5% for age compared to 6% of controls. To determine whether folate deficiency contributed to these observations, we measured serum and RBC folate concentrations: these were not significantly different between the 2 groups. We conclude that macrocytosis and leukopenia are common in children with DS.
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