Haematological change in sickle cell-haemoglobin C disease and in sickle cell-beta thalassaemia: a cohort study from birth

The haematological changes in early years following neonatal diagnosis have been observed in representative groups of children with sickle cell-haemoglobin C (SC) disease, sickle cell-á+ thalassaemia, and in sickle cell-á Thalassaemia. Most haematological indices in SC disease were intermediate between previously published values in SS disease and in AA controls, generally being closer to values in normal children, Eceptions were microcytosis which may be genetically determined and a striking elevation of mean cell haemoglobin cocentration from age 2 months to 4 years. The combination of a raised MCHC and a lowered MCV is unusual and may be characteristic of SC disease. Features in sickle cell-á thalassaemaia generally differed accordingly to the type of á thalassaemia gene. Sickle cell-B degree thalassaemia had lower levels of haemoglobin, MCHC, red cell count, MCV, and higher reticulocytes, most differences being significant before 1 year. No differences between SB degree thalassaemia and Sá+ thalassaemia were apparent in HbF levels (which resembled those in SS disease) or in HbA2 levels (which exceeded those in SS disease by 1 year of age).(AU)

Acute splenic sequestration and hypersplenism in the first five years in homozygous sickle cell disease

A cord blood screening programme initiated in June 1973 had screened 68 000 normal deliveries by February 1979 with the detection of 216 cases of homozygous sickle cell disease. Regular review of these children in the Medical Research Council paediatric clinic has identified acute splenic sequestration as a major cause of morbidity and mortality in the first 5 years of life. In addition to classical episodes characterised by peripheral circulatory failure, minor episodes of increasing anaemia associated with an enlargening spleen and an active marrow were also common. These minor episodes appeared to have predictive value in children who later developed severe life-threatening episodes ofacute splenic sequestration. Sustained hypersplenism was also appreciably more common in children developing minor or major episodes of acute splenic sequestration compared with those without such a history. It is proposed that the classification of acute splenic sequetration be expanded to include these minor episodes, and that consideration be given to prevention of recurrences by splenectomy particularly in patients who also develop sustained hypersplenism (Summary)

Outbreak of aplastic crises in sickle cell anaemia associated with parvovirus-like agent

Since 1952, 112 childen with sickle cell anaemia (SCA) in Jamaica have had an aplastic crisis. Outbreaks occurred in 1956, 1960, 1965-67, 1971-73, and 1979-80. Most cases occurred in children under 10 years of age, and an aplastic crisis in a patient over the age of 15 years is rare. There were 38 cases in 1970-80 and stored serum specimens from 28 of these were available for virus studies. Evidence for infection with a parvovirus-like agent was found in 24 of these 28 cases. Viral antigen was detected in 2 patients, both of whom demonstated seroconversion. Serconversion during 1980 was detected in a further 7, increasing amounts of antibody during the convalescent period were found in 5, antibody was found in 2 of 4 patients from whom only an acute phase specimen was available and the remaining 10 were antibody positive in the only convalescent phase sample available for testing. Antibody was found in 4 of 94 controls with the SS genotype (in retrospect 2 of these may have had an aplastic crisis) and in 17 percent of 48 controls with a normal haemoglobin (AA) genotype. The results accord with the possibility that the parvovirus-like agent is the principal cause of aplastic crisis in SCA (Summary)