Distribution of Kell phenotype among pregnant women in Sokoto, North Western Nigeria

Abstract

IntroductionKell antigen is highly immunogenic and is the common cause of antibody production in mismatched blood transfusions, haemolytic transfusion reaction (HTR) and maternal alloimmunization, which causes severe anaemia in neonates. The aim of this study is to determine the prevalence and ethnic variation of the Kell phenotype among pregnant women in Sokoto, Nigeria.MethodsKell antigen status of 150 pregnant women aged 18-45 years and mean age 27.19 ±4.69 years attending antenatal clinic in UDUTH Sokoto Nigeria was determined using the conventional tube method and anti-Kell reagents (Lorne Laboratories, UK).ResultsAmong the 150 subjects studied, 3 (2.0%) of subjects were positive and 147 (98.0) were negative for K antigen. Of the 150 pregnant subjects; 32 (21.3%) were primigravidae while 118 (78.7%) were multigravidae. Kell phenotype was more prevalent among primigravidae (3.1%) compared to multigravidae (1.7%) women. The distribution of Kell phenotype among the pregnant subjects was compared based on ethnicity. The prevalence of Kell antigen was significantly higher among the Hausa ethnic group (3.2%) compared to other ethnic groups which indicated zero prevalence (p = 0.001). Kell negative phenotype was ≥ 96.8% among all the ethnic groups.ConclusionOur observed prevalence of Kell phenotype is consistent with previous studies among Blacks and Asians but significantly lower than values observed in previous studies among Caucasians. We recommend that all pregnant women should be screened for the presence clinically significant red cell antigens including Kell antigen on their first antenatal visit. Kell negative red cell should be routinely provided for all pregnant women and women with child bearing potential to reduce the risk of Kell-associated HDFN. There is need to introduce routine screening of pregnant women for clinically significant red cell antibodies to facilitate the effective management of HDFN as well as prevent HTR. There is also need for sustained health education of pregnant women in the area to encourage early booking for antenatal care.

Rh and Kell blood group antigen prevalence in a multi-ethnic cohort in Nigeria: implications for local transfusion service

“…Unlike the Rh antigens, there are minimal reports on the distribution of K in Nigeria and no reports on the prevalence of other clinically significant Kell antigens. In our study cohort, no participants were positive for K. This finding is in agreement with the two existing studies of K in Nigeria (reported prevalence of 1% 15 to 2% 12,13 ) and what is reported for black populations in the United States. Notably, in our study cohort, the prevalence of all RBC antigens was not statistically correlated with ethnicity.…”

Red blood cell alloimmunization in pregnancy during the years 1996‐2015 in Iceland: a nation‐wide population study

“…The Kell antigen is a very immunogenic antigen, and anti‐K often appears after transfusion with Kell‐positive RBCs . Of 98 pregnancies in which anti‐K was detected in our study, 65 (66%) involved women who had previously received transfusions.…”

Evaluation and Frequency of Kell Erythrocyte Antigen in Blood Donors of Regional Blood Center of Passo Fundo, Brazil

“…For this reason Osaro et al (2015) conducted a research to know the KELL distribution in pregnant women in Sokoto, point out that there is a need for routine screening for clinical significance antibodies in pregnant women, as well as recommend that in the first prenatal visit must be held research to the most immunogenic antigens (24). The study also suggested to stock up negative K1 erythrocytes units for use in all pregnant women and women of childbearing age who require transfusion.…”