Which of the following blood group systems is associated with an increased risk of hemolytic disease of the newborn (HDN)?

A Kell blood group system ✓
B Duffy blood group system
C MNS blood group system
D All of the above

Explanation

The Kell blood group system is associated with an increased risk of HDN, as anti-Kell antibodies can cause severe hemolysis in the newborn.

Source

National Institute of Child Health and Human Development (NICHD) guidelines
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Medium MEDICAL Confidence: high