Blocking of fetal K antigens on cord red blood cells by maternal anti-K.
A 26-year-old Caucasian female in her second pregnancy grouped as A, D+ R(1)R(1) K- with anti-K (titre: 256) at booking. Her partner was typed as K1 positive. Baby was born with Hb 23.1 g/dl. Cord samples were referred to our laboratory for investigation and were found to be DAT 5+, IgG and anti-K was eluted from the red cells. Cord samples typed as A, R(1)r K- by DiaMed DiaClon Rh subgroups & K card. We report a case of false negative K1 phenotyping due to blocking with maternal anti-K.
Lee
E
E
Red Cell Immunohaematology, NHS Blood, West Middlesex University Hospital, London, UK. edmond.lee@nhsbt.nhs.uk
Redman
M
M
Owen
I
I
D000328:Adult; D001789:Blood Group Antigens / Q000097:blood*; D001788:Blood Grouping and Crossmatching; D004912:Erythrocytes; D005188:False Negative Reactions; D005260:Female; D005312:Fetal Blood; D006801:Humans; D007518:Isoantibodies / Q000097:blood*; D008297:Male; D011237:Predictive Value of Tests; D011247:Pregnancy
D001789:Blood Group Antigens; D007518:Isoantibodies