Medicolegal significance of human blood groups.

In blood group serology, a number of recent discoveries is of immense value in modern scientific knowledge. Among these ABO and Rh systems are of major clinical significance. Forensic application of blood group studies is of great value in detection of crime. Determination of paternity is another feather in forensic medicine after studying the blood group serology.

Evaluation of haemotherapy in thalassaemias (20 years of Indian experience).

Two hundred fifty-one patients of beta-thalassaemia ranging from 3 months to 15 years of age were evaluated. They were maintained on hypertransfusion regimen and received periodic transfusions of group specific packed red cells. These multiple transfused patients were subjected to the tests for detection of transfusion malaria, HBsAg and allo-antibodies against red cells. Malaria infection and HBsAg were detected in 6.4% and 15.5% of patients respectively, while allo-antibodies were detected in 15.5% of patients. Thirteen patients (5.18%) developed hypersplenism and associated pressure symptoms due to splenomegaly for which they underwent splenectomy. Postsplenectomy period was uneventful and showed marked decrease in the frequency and quantitative requirements of transfusions and overall improvement in health. The continuing steady improvement of the prognosis in thalassaemia secondary to hypertransfusion regimen required us to transfer attention to other problems involved in thalassaemia management such as problems of hypersplenism and problems of multiple transfusion.

Plasmodial antigen detection by monoclonal antibody as a screening procedure for blood donors in transfusion medicine.

Very little information is available as regards the methods to be advocated to prevent transfusion malaria, especially in endemic countries. Most of the malaria non-endemic countries follow the rule of donor deferral for 3 years after malaria infection. This criterion cannot be followed in endemic areas since the majority of the population is continuously exposed to this infection. Therefore, there was a long felt need for a suitable screening procedure for blood donors to make the transfusion therapy safe. A total of 6,435 blood donors and 3,621 patients who received blood from these donors were studied by blood smears examination and malarial antigen detection by specific monoclonal antibody. Smear examination by Giemsa and acridine orange staining methods showed poor results (0.06% and 0.1% positivity respectively), probably due to low concentration of parasites. However, antigen detection by monoclonal antibody confirmed specific diagnosis in majority of these subjects. Blood smear examination failed to reveal malaria infection in 92.3% of antigen positive blood donors. It is, therefore, recommended that antigen detection by monoclonal antibody should be adopted as a routine screening procedure by the blood transfusion services in malaria endemic countries like India.

Spectrophotometric analysis of amniotic fluid in Rh immunised pregnancies.

A total of 307 amniotic fluid analysis done in 344 Rh negative immunised mothers showed that 46, 83 and 178 delta OD values at 450 millimicrons fell in the upper, middle and lower zones of Liley's charts respectively. The correlation of spectrophotometric analysis with the condition of the baby at birth was about 95 per cent in the upper and lower zones. In the middle zone, however, it was about 75 per cent only. Also, in 7 women in whom the OD at 450 millimicrons fell in the middle zone, the babies were found to be Rh negative; in another baby, the OD difference fell in upper zone. In spite of these limitations amniotic fluid examination seems to be an important single guide to severity, being superior to other parameters like previous obstetric history, antibody titre alone and Liley's charts, which are still widely used.