(508) Risk Factors and Prognostic Markers Affecting Outcome in Sickle Cell Crisis

Introduction: The ability to identify patients with sickle cell anemia who are likely to have severe complications later in life would permit accurate prognostication and tailoring of therapy to match disease-related risks and facilitate planning of clinical trials.

Methods: We analyzed the records of 100 infants who received the diagnosis of homozygous sickle cell anemia or sickle cell–β0-thalassemia and for whom comprehensive clinical and laboratory data were recorded cross sectionally; data were available for a mean (±SD) of 18 years and above (maximum 57 years).

Results: Of the 100 patients in the cohort, 18 percent had an adverse outcome, defined as death (4), stroke (4), frequent pain (5), or recurrent acute chest syndrome (5]). Using multivariate analysis, we found three statistically significant predictors of an adverse outcome: an episode of dactylitis (defined as pain and tenderness in the hands or feet) before the age of 18 year (relative risk of an adverse outcome, 2.55; 95 percent confidence interval, 1.39 to 4.67), a hemoglobin level of less than 7 g per deciliter (relative risk, 2.47; 95 percent confidence interval, 1.14 to 5.33), and leukocytosis in the absence of infection (relative risk, 1.80; 95 percent confidence interval, 1.05 to 3.09).

Conclusions: Three easily identifiable manifestations of sickle cell disease that may appear in the early years of life (dactylitis, severe anemia, and leukocytosis) can help to predict the possibility of severe sickle cell disease later in life.