Medicos identify a rare blood group P null' phenotype

CHENNAI: A team of doctors led by Dr Shamee Shastry from the blood bank of Kasturba Medical College, Manipal, has identified a rare blood group called ‘pp’ or ‘P null’ phenotype recently.

The blood bank at the hospital received samples from a patient who required urgent blood transfusion. The doctors were unable to find a compatible blood unit even after cross matching with more than 80 units.

Extensive immunohematology workup was performed by the blood bank team and further for confirmation, samples were referred to the International Blood group Reference Laboratory (IBGRL), Bristol, UK for serological testing. 

With the help of reference laboratory, it was confirmed that the patient’s cells had the rare ‘pp’ phenotype. There are more than 200 minor blood group antigens known besides A, B and Rh. A blood type is considered rare if fewer than 1 in 1,000 people have it.  Dr Shamee Shastry, professor and head of the department of immunohematology and blood transfusion said, “The patient had a very rare ‘P’ null blood group and anti PP1Pk antibody in his blood that has a potential to cause acute intravascular hemolytic reaction to incompatible blood transfusion”.

“Rare donor registry will be of great help in managing such cases. Finding compatible unit for such case is a near impossible task without a well-established rare donor panel,” she said. Dr. Kiran Acharya, professor of orthopedics and his team performed blood less surgery once the patient’s hemoglobin was increased to the desired level using other medications.