Quantification of Sickle Cells in the Peripheral Smear as a Marker of Disease Severity

Figures & data

Figure 1.  Peripheral blood smear depicts a reversible (R) sickled cell and two irreversible cells (arrows). There is anisocytosis and target cells.

Table 1.  Sickle Index per Age Category, Genotype, and Treatment.

Category (N)	Mean % Sickled ± SD (95% CI)	Range %
Observed all aged <2 years SS + non-SS (N = 16)	0.60% ± 1.0 (95% CI 0.07–1.13)	0–3.07
Observed Age≥ 2 years SS only (N = 77)	6.16% ± 5.85 (95% CI 4.83–7.49)	0–29.97
Observed Age ≥ 2 years non-SS only (N = 15)	0.77% ± 1.23 (95%CI 0.09–1.46)	0–4.53
Total observed (N = 108)	4.59% ± 5.56 (95%CI 3.53–5.65)	0–29.97
Hydroxyurea treatment (N = 15)	4.84% ± 3.30 (95% CI 3.02–6.67)	0.35–12.37
On transfusions (N = 32)	3.68% ± 3.20 (95%CI 2.52–4.83)	0–11.16

Figure 2.  The plot demonstrates a gradual increase in sickle cell index (SCI) as patient's age progresses.

Figure 3.  Quartile distributions for SCI for all SS patients 2 years and older. TRJV: tricuspid valve jet velocity.