Parasitic infections in sickle cell crisis: Nigerian experience

Data collected on 150 sickle cell patients in Nigeria were analyzed to determine the frequency of parasitic infections in clinical and hematologic crisis. Fifty-three adult and 97 pediatric patients (mean age: 27.6 years and 9.7 years, respectively) were studied. Of these patients, 82 were males and 68 females. One hundred thirty-nine had the SS and 11 the SC genotype. Blood samples collected from patients on admission for sickle cell-related illnesses were examined microscopically for evidence of Plasmodium sp, and stool samples were analyzed for presence of any helminth. A total of 102 parasitic infections associated with clinical cases of sickle cell crisis were recorded (malaria, 36[35.3%]; helminths, 49 ([48%]; and malaria and helminths together, 17 [16.7%]). Of the 49 helminthic infections, 26 (53.1%) were due to Ascaris lumbricoides, 15 (30.6%) were due to hookworms, 7 (14.3%) were due to Trichuris trichiura, and 1 (2%) was due to Strongyloides stercoralis. The mean hemoglobin levels during clinical crisis were 7.1 g/dL for helminths, 6.4 g/dL for malaria, and 6.1 g/dL for malaria and helminths together. Reticulocyte counts were 1.4% for helminths, 1.5% for malaria, and 1.2% for both malaria and helminths together. Severity and duration of the clinical crisis were longer for events associated with a single parasitic organism infection than for those with multiple organisms. Routine blood smear examination for malaria and stool analysis should be included in the laboratory evaluation of individuals with sickle cell anemia in developing countries as these infestations could play an important role in precipitating a crisis.