Cold Agglutinin Clue
Patient says fingers turn blue in the cold?
Think Cold Agglutinin Disease — an autoimmune hemolytic anemia
Triggered by cold temps → antibodies agglutinate RBCs
Causes:
• Mycoplasma pneumoniae
• EBV
• Lymphoma
Clue: RBC clumping on blood smear
Cold outside, clumped inside — the blood chills too!