Doctors from Mangaluru's KMC identify rare bloodgroup ‘P null’ phenotype

Samples were referred to the International Blood Group Reference Laboratory (IBGRL), Bristol, U.K., for serological test.

Example of a superbug Electron micrograph of methicillin-resistant Staphylococcus aureus (in yellow) and a dead human neutrophil, a type of white blood cell. MRSA is a bacterium that causes skin infections in humans. It's tougher to treat than most strains of staphylococcus aureus because it's resistant to some commonly used antibiotics. Photo: Wikimedia Commons

A team of doctors, led by Shamee Shastry from the Blood Bank of Kasturba Medical College (KMC) here, has identified a rare blood group called “pp” or “P null” phenotype.

A press release issued by the Manipal Academy of Higher Education (MAHE) here recently said that 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 fewer than one in 1,000 people have it. A person is said to have 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 urgent blood transfusion. The doctors were unable to find a compatible blood unit even after cross-matching it with more than 80 units.

Extensive immunohaematology work-up was performed by the team and further for confirmation, samples were referred to the International Blood Group Reference Laboratory (IBGRL), Bristol, U.K., for serological test.

With the help of the reference laboratory, it was confirmed that the patient’s cells had the rare “pp” phenotype.

Poornima Baliga, Pro-Vice Chancellor, MAHE, said that it was for the first time that the “P blood group null phenotype has been detected in India”. She said that she supported the Blood Bank’s initiative to build rare donor registry for the region.

Dr. Shastry, Head, Department of Immunohaematology and Blood Transfusion, said, “The patient has the very rare ‘P null’ blood group and anti-PP1Pk antibody in his blood that has the potential to cause acute intravascular haemolytic 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.

Kiran Acharya, professor of Orthopaedics and his team, performed blood-less surgery (Femur fracture repair) once the patient’s haemoglobin was increased to the desired level using other medications.

Pragna Rao, Dean, KMC, congratulated the team, the release said.