Drépanocytose homozygote chez l'adulte ivoirien de plus de 21 ans

Abstract

Sickle cell disease is a genetic disease characterized by the synthesis of an abnormal haemoglobin called haemoglobin S. It is the most frequent of the hereditary anomalies of haemoglobin and occurs most commonly in individuals of African descent. Various treatments have considerably improved its prognosis, prolonging the survival of patients, especially those with the most severe, homozygous form. The objective of thisstudy is to describe the epidemiologic, clinical, and laboratory characteristics as well as the disease course and available treatments in adults (aged 21 years or older). This retrospective, descriptive, analytic and non-comparative study included 48 adults of both sexes with homozygous sickle cell disease. Their mean age was 26.1 years (range: 21 to 56 years, and sex ratio 1.3. In all, 70.8% had clinical anaemia, 83.3% were subicteric or icteric and 8.3% had hepatomegaly. Spleen size was normal in 41.7% of patients, and atrophic in 37.5%. No case of splenomegaly was noted and 8.3% had been splenectomised. Haemoglobin rates ranged from 4 g/dL to 12.7 g/dL with an average of 9.5 g/dL, haemoglobin S levels from 83 to 93% with an average of 85.3%, and haemoglobin F levels from 3.5 to 17% with an average of 10.6%. The percentage with fewer than three crises (vasooclusive or haemolytic or both) in a year was 68.7%; 27.1% had from three to five crises, and 4.2% more than five. Disease complications included anaemia in 43.7%, infections in 18.8% and ischaemia in 16.7%; 20.8% had no complications. Age at the beginning of treatment was younger than 5 years in 56.25%, from 5 to 10 years in 29.2%, and older than 10 years in 14.6%. Medical follow-up was regular for 68.7% and irregular for 31.2%. Vaccination was up to date in 58.3. Most patients (83.3%) adhered to their maintenance treatment. In all, 41.7% had not had any blood transfusions, 54.2% had had one or two transfusions, and 4.2% three or more. We compared the patients aged 26 years or younger with those older than 26 and studied the influence of age on different disease variables. Age did not affect the frequency of crises (p = 0.368) or of infections (p = 0.116), the rates of haemoglobin (p = 0.221), haemoglobin S (p = 0.44), or haemoglobin F (p = 0.35), or complications (p = 0.56). Nevertheless, we noted that the frequency of crises, infections, and anaemic complications were higher among the younger patients. Early treatment, regular medical follow-up, maintenance treatment and vaccination have all improved the prognosis of homozygous sickle cell disease considerably. These patients have reached adulthood with relatively few chronic complications.