Carlos Penalillo Pimentel: Detection of Rare Blood Donor Phenotypes During Investigation of Serologic Discrepancies
Carlos Penalillo Pimentel, Affiliate member of the Peruvian Association for Quality in Health, shared a post on LinkedIn:
“Immunohematology
That is why this science is exciting and takes us to totally unexpected, unsuspected and statistically unthinkable destinations.
I arrive at my Service having scheduled to study some modification to the acid elution technique so that it is not so aggressive with red blood cells, we have 3 patients with autoimmune hemolytic anemia (AHAI) and we need to ensure that the units of blood we send them are as accurate as possible in compatibility and with identical phenotype.
One proposes and God disposes, I arrive and find on the work table a strong discrepancy of globular and serum group from the routine of the previous day, I focused on solving it while controlling the 3 autoanalyzer equipment that we manage. It was solved with the enzymatic method.
We also needed to perform phenotype extended to blood units, I selected from the previous day 12 R1R1 and 12 R2R2, from all of them, we are separating those special ones that serve us in cases of incompatibilities known as Anti M, Anti s, Anti Fy a, etc.
The usual thing is to find 2 or 3 negative Fy from the group of 24, today we had 5 and with great surprise two of them were Fy null, that is to say Fya – Fyb – (the ones in the photo)
In all these years that we have been looking for donors with an uncommon phenotype, we have only managed to genotype 2.
Something incredible, we will proceed to carry out molecular biology to enter them on the Peruvian list. These donors will one day save the life of a patient with that same uncommon phenotype, that is the supreme purpose of our work area, to provide solutions in a safe and timely manner.”

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