Q: We have raised funds for a boy of 4 years for his bone marrow transplantation. The operation is over and he is currently under observation at a hospital in Vellore. He requires a lot of platelet transfusion now, and his father is finding it extremely difficult to find platelet donors as this requires apheresis. Firstly, can you give some contacts at Vellore who will able to help the boy by arranging for platelets? Secondly, is it not possible to take normal blood donation and then use it for apheresis to harvest the platelets? This question came to my mind because today I donated blood for a leukaemia patient, and the purpose was the same. The patient requires platelet and we all donated blood, from different blood groups. On questioning I learnt that this blood will now be put under apheresis and the platelets will be harvested. I do not understand why can they not follow the same at Vellore, since they have a lot of willing donors for normal blood donation but no donor is ready to go through the process of apheresis.

A:When whole blood is donated, the blood is separated into its components usually red cells, platelets and plasma. Apheresis is a process in which only a specific component of the blood is harvested (usually platelets) and the rest of the blood is returned to the donor. One apheresis donation provides as many platelets as 5-6 whole blood units, i.e. platelets from 5 to 6 donors have to be combined to yield the same volume as obtained by apheresis from a single individual. The disadvantage of whole blood platelet concentrates is that a patient is exposed to antigens from each donor, thus sensitising him and decreasing the effectiveness of platelet transfusion over a period of time. The father will need to speak to the doctors & social workers at Vellore who will be able to guide them regarding availability of donors in local NGOs, Red Cross or other organisations.