A team of doctors, led by Dr Shamee Shastry of the blood bank of Kasturba Medical College, Manipal, has identified a rare blood group called ‘pp’ or ‘P null’ phenotype.
ABO and Rh D are the commonly typed blood group systems. However, there are more than 200 minor blood group antigens known besides A, B and Rh.
A blood type is considered rare if there are fewer than 1 in 1,000 people who have it. A person is said to have a rare blood group when he lacks the high-frequency antigen or multiple common antigens.
The blood bank at Kasturba Hospital received samples from a patient who required an 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 a reference laboratory, it was confirmed that the patient’s cells had the rare ‘pp’ phenotype.
Dr Poornima Baliga, pro vice-chancellor of the faculty of health sciences, MAHE, said that it is for the first time that P blood group null phenotype was detected in India and she supported the blood bank’s initiative to build rare donor registry for the region.
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 an acute intravascular hemolytic reaction to incompatible blood transfusion.”
“Rare donor registry will be of great help in managing such cases. This antibody is also known to cause recurrent abortions in women. 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 bloodless surgery (Femur fracture repair) once the patient’s haemoglobin was increased to the desired level using other medications.