Hemoglobinopathies are a group of diseases caused by structural alterations and/or defects in hemoglobin synthesis. The most frequently described genotypes worldwide are SS, SC, and HbS/β-thalassemia (Sβ). These genotypes present marked clinical heterogeneity and diverse hematological outcomes.

To describe the significant differences in laboratory data among SS, SC, and Sβ genotypes from patients that were at the Amazonas State Hematology and Hemotherapy Foundation (HEMOAM).

This was an observational and descriptive study, with a retrospective analysis of clinical laboratory data obtained from the electronic medical records.

A total of 230 SS patients (83.6%), 23 SC (8.4%) and 22 Sβ+ (8.0%) participated in the study. The mean fetal hemoglobin (HbF) levels were highest in HbSβ+ patients (11.15%), followed by HbSS patients (9.46%) and HbSC patients (3.63%) - (p < 0.001). Mean total hemoglobin levels were similar between the HbSS (8.39 g/dL) and HbSβ+ (8.40 g/dL) groups and were both significantly lower than the HbSC group. These results reflect a pattern of chronic anemia in more severe forms of the disease (p < 0.001). The mean reticulocyte count was highest in the HbSS group (9.16%), followed by the HbSβ+ group (6.11%) and the HbSC group (4.76%). This indicates increased bone marrow activity in response to chronic hemolysis (p < 0.001). Regarding serum iron, the mean was 118.87 µg/dL por HbSS group, while 111.21 µg/dL in HbSβ+ group. The mean ferritin level was higher in HbSS group (824.95 ng/mL) than in those HbSβ+ group (542.83 ng/mL) and HbSC (328.28 ng/mL), however, these differences were not statistically significant (p = 0.210). Discussion: The laboratory findings corroborate the pattern previously described in the literature, the HbSS genotype presents the most altered hematological parameters, which is consistent with greater clinical severity. Conversely, HbSC patients exhibited milder laboratory findings, which corroborates their generally milder clinical presentation. The elevated levels of serum iron and ferritin levels in HbSS and HbSβ+ patients can be attributed to the frequency of transfusions and persistent hemolysis, despite the absence of statistical significance between the groups. Conclusion: These results demonstrate the laboratory differences among sickle cell disease genotypes and the importance of clinical correlations, highlighting the severe profile of HbSS patients. We emphasize the need to expand neonatal screening to enable early diagnosis in this population, improve therapeutic follow-up, prevent severe hemolysis episodes, and, most crucially, optimize clinical outcomes for these patients.