Cold agglutinins with the rare anti-Pr specificity were identified in
an adult patient with fresh varicella infection. The antibody was of t
he IgM x type with subspecificity anti-Pr3d and caused a haemolytic ep
isode in the patient. In the only previously reported case in which co
ld agglutinins were associated with varicella infection, the antibody
specificity was also anti-Pr.