Cold Agglutinin Disease

A chronic complement-mediated disease, driven by an IgM-producing clone, where treatment decisions depend more on trajectory and clinical impact than on laboratory thresholds.

Cold agglutinin disease (CAD) is a chronic complement-mediated hemolytic anemia in which the mechanism is relatively clear but management is rarely automatic. Patients may live for years with fluctuating symptoms, seasonal triggers, and variable clinical impact. Understanding CAD requires more than knowing its biology. It requires understanding how an IgM-producing clone drives complement-mediated hemolysis, how that biology appears in clinical practice, and how clinicians decide when to observe, when to intervene, and whether to target hemolysis or the underlying clone.

Start Here

If you are new to CAD, begin with the foundational clinical sequence: definitions, clinical presentation, diagnosis, and treatment strategy. These sections establish the core mechanism and the major decision points. Later sections explore uncertainty, patient experience, evidence interpretation, and applied clinical reasoning.

Recommended starting path
Definitions → Clinical Presentation → Diagnosis → Treatment Strategy