No abstract

Measurements of the coagulation system were carried out in children with sickle cell disease (SCD) in both steady state and on the 1st day of painful crisis and were compared to age- and sex-matched healthy controls. No significant differences were found in prothrombin time, partial thromboplastin time, thrombin time, reptilase time, plasma fibrinogen, antithrombin III, factor VIIL·C, ristocetin-cofactor (Ri-Cof) and platelet aggregation responses to ADP, collagen and adrenaline. Abnormal aggregation responses to ristocetin were noted in all patients with SCD when compared to controls. Daily measurements during the first 4 days of painful crisis showed significant elevation of fibrinogen and Ri-Cof and enhancement of aggregation to ADP and adrenaline by the 3rd day of crisis. It was concluded that the changes noted, rather than being primarily responsible for the onset of crisis, can only be secondary changes arising from the aetiological factors of crisis, i.e. stasis and acute-phase proteins.

A 6-year-old girl with sickle cell disease was admitted to the hospital with the diagnosis of the acute chest syndrome. The laboratory findings and the radionuclear lung scan supported a diagnosis of pulmonary infarction rather than pneumonia. She improved with intravenous fluids, oxygen, penicillin, and theophylline. The most likely explanation for the rapid resolution of the clinical syndrome, the chest x-ray, and lung scan abnormalities is that masses of sickled cells caused transient pulmonary vascular occlusion leading to perfusion defects and ischemia, and that the sickled cell thrombi were dislodged before the infarction occurred. To our knowledge, this phenomenon has not been described as a cause of the acute chest syndrome in sickle cell disease in children.

A cross-sectional study was carried out to determine the prevalence of iron deficiency among healthy Saudi children from birth to 15 months of age. The groups studied were: newborns, 3-4 months, 5-6 months, 7-8 months, 9-10 months and 12-15 months of age. The age groups were dictated by the vaccination schedule. Serum ferritin was measured and transferrin saturation calculated in each subject. The lower limits of normal were taken as a transferrin saturation of less than 10% and a serum ferritin of less than 12 micrograms/l. A total of 333 serum samples was adequate for analysis. None of the newborns or the 3-4-month-old infants had evidence of iron deficiency. At 5-6 months only 3.3% of subjects had iron deficiency. In the subsequent older age groups the prevalence of iron deficiency increased significantly with age from 9.3% to 12.7% and reached 14.5% in the oldest age group. Screening for iron deficiency in children attending well-baby clinics and hospitals at ages of 12-15 months is recommended.

Forty children homozygotes for sickle-cell disease (SCD) aged 2-5 years were enrolled in a study to assess the efficacy of pneumococcal vaccine combined with penicillin prophylaxis in preventing pneumococcal infection. The vaccine was given initially and then every 2 years as a booster. In addition to pneumococcal vaccine, 24 children were prescribed penicillin-V orally twice daily while the remaining 16 were given benzathine penicillin intramuscularly every 4 weeks in the clinic. The study period lasted for 4 years during which the clinic attendance rate of both groups was 90% and 92% respectively. The compliance with oral penicillin intake was checked by random urine testing for penicillin. The test was positive in 128 out of 320 urine samples (40%). The parenteral penicillin was given at every clinic visit and the rate of compliance was 92%. Twelve episodes of bacterial sepsis were documented: 10 of them were caused by Gram-negative organisms. The pneumococcus caused a fatal episode of septicaemia and meningitis in a child who did not comply with penicillin prophylaxis. In a retrospective search, 15 episodes of bacterial sepsis have been documented in 22 children receiving no prophylaxis for 2 years. Eight of those episodes were caused by the pneumococcus. The combination of pneumococcal vaccine with penicillin prophylaxis was effective in preventing pneumococcal sepsis in children with SCD followed up for 153 patients years.