Table 1_Case Report: Severe mixed autoimmune hemolytic anemia associated with acute cytomegalovirus infection in an immunocompetent adult.docx

On hospital day 4, he developed dark brown urine, with hemoglobin falling to 40 g/L and laboratory evidence of acute hemolysis. Extended DAT revealed IgG, IgA, IgM, and C3d coating of erythrocytes, and cold agglutinin testing identified an IgM cold agglutinin with a titer of 1:128 and thermal amplitude extending to 37 °C, supporting severe CMV-associated mixed AIHA. After antiviral therapy, immunomodulatory and supportive treatment, hemolysis was controlled, and hemoglobin stabilized without further transfusion.</p>Conclusions<p>CMV-associated HA may rarely present as severe mixed AIHA in immunocompetent adults.

In severe or atypical cases, comprehensive immunohematologic evaluation beyond routine DAT, including extended DAT, cold agglutinin titration, and thermal amplitude testing, is essential for accurate subtyping. In severe cases, early integrated therapy targeting both CMV replication and immune-mediated hemolysis may be required.</p>