|Year : 2015 | Volume
| Issue : 1 | Page : 30-31
Reporting a rare RH phenotype D-
Farzad Molahosseini Foomani1, Seyyede Fatemeh Shams2, Zahra Arian Pour1
1 Blood Transfusion Organization Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
2 Hematology Researcher, Department of Hematology and Blood Banking, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
|Date of Web Publication||15-Apr-2015|
Farzad Molahosseini Foomani
Iran Blood Transfusion Organization. Dr. Shariaati sq. Mashhad
Source of Support: None, Conflict of Interest: None
Of all blood group systems, Rh is one of the most important blood groups, which its compatibility is one of the essential principles of transfusion. Two genes (RhD and RhCE) locate on chromosome 1, which encode the Rh proteins. RhD is an immunogenic antigen. A 49-year-old man was studied in this report, who received two O + packed cells 1-time without molecular compatibility. He was hospitalized for kidney transplantation in hospital and reiterative mismatch crossmatches were seen. Serologic tests of patients show a rare Rh phenotype (D-), with a frequency of 1 in 10,000. Screening between family members was done to find a compatible donor.
Keywords: Antigen, D-phenotype, transfusion, Rh system
|How to cite this article:|
Foomani FM, Shams SF, Pour ZA. Reporting a rare RH phenotype D-. J Appl Hematol 2015;6:30-1
| Introduction|| |
Rh is the most important blood group after ABO, whose compatibility is considered as a basic condition. , Rh antigens have a vital role as ammonium channels on the erythrocyte surface, , and are inherited by two genes D and CE located on chromosome number 1. 
These two genes are taking place in different gene loci, each one having 10 exons, which encode polypeptides with 22-25 amino acids in length.  These polypeptides associate with Rh AG antigen and Rh precursor and form antigenic complex of Rh. 
D antigen has an immunogenic activity and, in fact, determines Rh type.  Pregnancy and transfusion induce alloimmunization against Rh antigens because of different CE haplotypes in the population. 
D-phenotype is one of the rare phenotypes of Rh system that appears as a result of mutation in both alleles of CE locus gene. It was first reported by Race and Sanger in 1950. Persons with this phenotype have no antigen on antigenic complex of Rh, except D. In this report, we describe a patient with renal failure and D-phenotype. 
| Case report|| |
The case of renal failure was diagnosed in a 49-year-old man who was referred to the medical center. Reviewing the patient's medical histories demonstrated that at the age of eighteen, he was suffering from kidney stones which have become chronic kidney disease by over time, and eventually turned into a complete failure. He was under dialysis as a part of treatment. He received two units of O + blood group once.
After referring to the medical center for a kidney transplant, reiterative mismatch cross matches occurred for patients. His clotted blood sample was sent to Mashhad international blood transfusion organization. Serologic tests results and the erythrocyte phenotype are shown in [Table 1] and [Table 2], respectively.
Results of serologic tests reveal D-phenotype in Rh system; it means that there is just D antigen from Rh system, and neither C nor E antigens appear.
Considering the low prevalence (1/10,000) of this phenotype, it was very hard to find compatible blood for this patient, so we looked for a donor among his family members. 20 people of the patient's relatives were demanded and necessary tests of donation were done on their samples, such as: Cell type, back type, and Rh phenotyping, and viral serologic tests were done on their blood samples. Among these 20 people, his son with blood group A had compatible Rh phenotype, but because of the major blood group incompatibility, he was exempted from blood donation.
Following-up with this patient, two units of O + group D-phenotype were prepared by another center and delivered to hospitals for a kidney transplant.
| Discussion|| |
Antibody screening test results reveal a rare erythrocyte phenotype with an incidence of 1/10,000. The first transfusion induced immune stimulation and formed alloantibody against absent antigens (C and E). It was not done with erythrocyte phenotype determination and was only done according to the Rh positive result in cell type. It is a very sensitive and hard work to prepare blood for patients with alloantibody.
In a report of D-phenotype, it has been suggested to prepare and freeze autologous blood units for rare phenotypes, provide nonanemic condition to prevent complication occurrences and save the golden time of treatment.
Rh alloantibodies are one of the frequent causes of hemorrhagic diseases; according to the clinical significance of these antibodies, plasma exchange is recommended in hemolytic disease of new born to reduce the amount of alloantibodies in serum and complications resulting from alloantibodies. 
The best and the most available method to find the compatible blood donor is to look for the person among the relatives. Although preparing and storing antisera for erythrocyte phenotyping is not available for all centers, due to the immunologic role of Rh antigens in transfusion complications, erythrocyte phenotyping is suggested in people with history of rare blood group in their family to lessen these effects.
| References|| |
Westhoff CM. The Rh blood group system in review: A new face for the next decade. Transfusion 2004;44:1663-73.
Westhoff CM. The structure and function of the Rh antigen complex. Semin Hematol 2007;44:42-50.
Salamat N, Bhatti FA, Hussain A. Anti-Rh17 (anti-Hr0): A rare diagnostic and management problem. J Pak Med Assoc 2004;54:215-8.
Huang CH, Peng J, Chen HC, Chen YX, Lin DT, Lin SW, et al.
RH locus contraction in a novel Dc-/D - Genotype resulting from separate genetic recombination events. Transfusion 2004;44:853-9.
Avent ND, Madgett TE, Lee ZE, Head DJ, Maddocks DG, Skinner LH. Molecular biology of Rh proteins and relevance to molecular medicine. Expert Rev Mol Med 2006;8:1-20.
Schenkel-Brunner H. Human Blood Groups: Chemical and Biochemical Basis of Antigen Specificity. 2 nd
ed. Springer, verlag wien, New York; 2000. p. 409-57.
Flatt JF, Musa RH, Ayob Y, Hassan A, Asidin N, Yahya NM, et al.
Study of the D - Phenotype reveals erythrocyte membrane alterations in the absence of RHCE. Br J Haematol 2012;158:262-73.
[Table 1], [Table 2]