Clinical, hematological and genetic features of sickle-cell anemia and sickle cell-β thalassemia in a Brazilian population

Clinical, hematological and genetic studies were carried out on 40 patients with symptomatic sickle-cell disease, selected on the basis of a predominant HbS fraction and absence of other abnormal hemoglobin variants. Family studies showed they included 26 homo-zygotes for the sickle-cell gene (SS) and 14 double heterozygotes for both the sickle-cell and the β°-thalassemia genes (Sβ°-thalassemia). Comparison of the two groups revealed the more common occurrence of splenomegaly, lower MCV and MCH, and higher HbAa in Sβ°-thalassemia. Total hemoglobin was slightly lower in SS disease but the difference was not significant. Fetal hemoglobin (HbF) was moderately elevated to similar levels in both groups. These results suggest a high incidence of Sβ°thalassemia in certain Brazilian mixed populations and confirm the severity of the double heterozygous state. The distinction between the two disorders is often difficult, but can be made on the basis of the hematological data taken together with family studies.     

A rapid whole blood solubility test to differentiate the sickle-cell trait from sickle-cell anaemia

A simple and rapid screening test which differentiates sickle-cell trait and sickle-cell anaemia is described. The test utilizes 0.1 ml of whole blood and is based on the low solubility of reduced sickle haemoglobin. Results intermediate between the sickle-cell trait and sickle-cell anaemia are obtained in unusual cases of sickle-cell anaemia with high foetal haemoglobin.The need to supplement the results with haematological and electrophoretic techniques is discusses.     

Leg ulcer in a case of thalassemia minor (a case report)

A rare case of leg ulcer in a 28 years old woman with thalassemia minor is reported.     

Unusual bone marrow hyperplasia in a case of thalassemia intermedia

A case of beta thalassemia intermedia is described. Beside the typical hematologic picture and extramedullary erythropoiesis in the liver always present in such a clinical form, atypical masses due to foci of erythropoiesis were found at paravertebral, parasternal and subcostal sites. The size of these masses caused problems in differential diagnosis; they have been solved by computerized axial tomography.     

Coagulation fibrinolysis in sickle-cell disease

A study of fibrinolytic activity in sickle-cell patients during asymptomatic periods has shown a normal fibrinolytic response to exercise and local heat to the arm. During vasoocclusive crises there was no significant decrease in fibrinolytic activity. These results contrast with earlier reports of decreased fibrinolysis during crisis and a suggestion that fibrinolytic activators might be of value in preventing vasoocclusive episodes.Patients in painful crisis showed a significant rise in fibrinogen concentration and fall in platelet count. The former may contribute to localized vascular sludging by increasing whole-blood viscosity, while the latter probably results from local trapping of platelets in areas of sickling or from subsequent splenic sequestration of damaged platelets. There was no evidence of disseminated, as opposed to localized, intravascular coagulation during crisis.     

β-地中海贫血合并δ β-地中海贫血一个家系的产前诊断

目的对1例β-地中海贫血合并δβ-地中海贫血的家系进行产前诊断。方法用PCR-反向点杂交和长链PCR技术对胎儿进行产前基因诊断。结果母亲为β-珠蛋白基因密码子41/42（？TTCT）突变杂合子,父亲为缺失型Gγ＋（Aγδβ）0突变杂合子,胎儿基因型正常。结论对一个家系中出现重型β-地中海贫血患者,但用常规方法只能找到一个基因突变时,应考虑缺失突变的可能,并用合适的方法验证,然后才能产前诊断。