Monitoring Kell antigen levels in pregnancies affected by hemolytic disease of the fetus and newborn (HDFN) secondary to Kell antigen incompatibility could help physicians determine the need for intrauterine transfusions, according to a recently published study in Hematology, Transfusion, and Cell Therapy.
HDFN is caused by blood type incompatibility between the mother and the fetus; this incompatibility leads to the development of antibodies, which, in a second pregnancy, can cross the placental barrier and destroy fetal red blood cells, leading to consequences such as anemia and permanent neurological damage (kernicterus). Blood type incompatibility is due Rh antigen incompatibility and ABO antigen incompatibility in most cases.
Although less common than the previous two, Kell antigen incompatibility is associated with a strong immune reaction that often leads to severe HDFN. Furthermore, Kell proteins play a significant role in red blood cell (RBC) growth, so HDFN, due to Kell antigen incompatibility, can also suppress RBC production.
Learn more about HDFN prognosis
“Maternal Kell alloantibodies cause severe disease in the fetus and newborn in the early weeks of gestation, therefore, early management and proper monitoring are required,” the authors wrote.
The authors aimed to determine whether measured Kell antigen titers could help physicians prognosticate the outcome of the pregnancy and possible sequelae. To this end, researchers performed an extensive search in renowned medical databases identifying over 5000 articles and selecting 10 which met the exclusion criteria.
Results showed no statistically significant correlation between Kell antigen titers and the incidence of complications such as fetal death or massive fetal liquid accumulation (hydrops). However, titers did seem to correlate with the timing of intrauterine blood transfusions.
“The Australian and New Zealand Society of Blood Transfusion (ANZSBT) recommends anti-K1 titre monitoring every four weeks until the 28th week of gestation. After 28 weeks of gestation, weekly antibody titre monitoring is recommended 418 in foeto-maternal units,” the authors concluded.
