[Monitoring pregnant patients from risk countries with sickle cell disease and thalassemia. Clinical aspects, screening and prenatal diagnosis].

At the present time, about 3.5 million people from Turkey, Greece, Italy, the Middle East, Africa and Asia are living in Germany. They are potential carriers of beta-thalassaemia and haemoglobinopathies such as sickle cell disease. These diseases are new for most of us and represent a challenge to physicians, taking care of these patients. Not only do we have to learn about the clinical problems of homozygous patients and how to handle them, we also have to become acquainted with the problems related to the heterozygous carrier stage. The large number of asymptomatic pregnant carriers of beta-globin anomalies is a particular challenge for obstetricians. They need to identify carriers through haemoglobin electrophoresis screening, inform the carrier about the meaning of being a carrier, screen the woman's partner, refer for genetic counselling and suggest and explain prenatal diagnosis in case the partner is also a carrier. There is as yet no cure for thalassaemia and sickle cell disease, except for bone marrow transplantation in a few selected cases. Therefore, prenatal diagnosis presents a valuable method of preventing severe chronic diseases. Screening does not only allow genetic counselling, the information gained has also clinical implications for carriers of beta-thalassaemia. In this paper a summary is given of the pathophysiological and clinical features of thalassaemia and sickle cell disease and molecular biology methods to diagnose thalassaemias and sickle cell disease are discussed. In addition, a screening programme for pregnant women from countries at risk is suggested to enable physicians to give optimal care and initiate prenatal diagnosis.