BACKGROUND: The present report illustrates a case with rare "P null" phenotype due to a large deletion in chromosome 22q13.2 and with clinically significant anti-PP1P<sup>k</sup> antibody. Patient blood management in such cases is challenging. CASE REPORT: The transfusion center supporting the tertiary care referral center in the southern part of India received a blood sample from a trauma case for pre-transfusion testing. An antibody to a high-frequency blood group antigen was initially suspected. Following extensive immune-hematological workup, the patient was diagnosed to have naturally occurring anti-PP1P<sup>k</sup> antibody and a rare "P null" phenotype. The genomic DNA of the patient was analyzed by exome sequencing followed by Sanger's sequencing. Molecular diagnostics revealed a large 21-bp deletion in chromosome 22q13.2 which encodes the A4GALT gene, resulting in truncation of seven amino acids I245-251P and resulted in rare "P null" phenotype. Patient blood management strategies were adopted to manage the patient conservatively without blood transfusion. CONCLUSION: A large deletion in chromosome 22q13.2 had resulted in a rare "P null" phenotype in the present case. The patient was a victim of a road traffic accident, required emergency hospitalization, as well as surgical intervention, and his plasma had antibodies to high-frequency antigens. A rare donor registry plays a major role in providing transfusion support to such cases.
BACKGROUND: The present report illustrates a case with rare "P null" phenotype due to a large deletion in chromosome 22q13.2 and with clinically significant anti-PP1P<sup>k</sup> antibody. Patient blood management in such cases is challenging. CASE REPORT: The transfusion center supporting the tertiary care referral center in the southern part of India received a blood sample from a trauma case for pre-transfusion testing. An antibody to a high-frequency blood group antigen was initially suspected. Following extensive immune-hematological workup, the patient was diagnosed to have naturally occurring anti-PP1P<sup>k</sup> antibody and a rare "P null" phenotype. The genomic DNA of the patient was analyzed by exome sequencing followed by Sanger's sequencing. Molecular diagnostics revealed a large 21-bp deletion in chromosome 22q13.2 which encodes the A4GALT gene, resulting in truncation of seven amino acids I245-251P and resulted in rare "P null" phenotype. Patient blood management strategies were adopted to manage the patient conservatively without blood transfusion. CONCLUSION: A large deletion in chromosome 22q13.2 had resulted in a rare "P null" phenotype in the present case. The patient was a victim of a road traffic accident, required emergency hospitalization, as well as surgical intervention, and his plasma had antibodies to high-frequency antigens. A rare donor registry plays a major role in providing transfusion support to such cases.
Authors: Hollie M Reeves; Victoria Cary; Mary Ann Mino; Claire McGrath; James A Westra; Connie Piccone; Katharine A Downes Journal: J Pediatr Date: 2016-11-14 Impact factor: 4.406
Authors: Radoslaw Kaczmarek; Katarzyna Mikolajewicz; Katarzyna Szymczak; Maria Duk; Edyta Majorczyk; Anna Krop-Watorek; Anna Buczkowska; Marcin Czerwinski Journal: Glycoconj J Date: 2016-08-18 Impact factor: 2.916
Authors: Ashish N Kanani; Snehal B Senjaliya; Manisha M Rajapara; Judith Aeschlimann; Connie M Westhoff; Sanmukh R Joshi Journal: Transfus Med Hemother Date: 2021-02-25 Impact factor: 3.747