Phase 1 · Understand the Body — Why the disease behaves the way it does.
The One-Line Truth
The whole disease in one chain
Everything on this page exists to explain this line.
The immune system mistakes the patient's own red blood cells for foreign invaders and destroys them faster than the bone marrow can replace them.
Security System Gone Rogue
Imagine a warehouse where security guards (B lymphocytes) are supposed to check ID badges on delivery trucks (red blood cells) and only stop the broken or expired ones. One day, the guards start seeing the legitimate company logo (self-antigens like Rh proteins) as a threat and begin sticking 'DESTROY' labels (IgG antibodies) on every truck with that logo. The warehouse's cleanup crew (splenic macrophages) sees these labels and immediately crushes the marked trucks in the loading dock (spleen), removing them far faster than the factory (bone marrow) can build new ones. Meanwhile, the delivery network starts failing because there are fewer trucks available, and the factory is working overtime trying to replace them—but it's falling further and further behind. The remaining trucks are forced to make faster deliveries, and the whole operation is straining under the pressure.
American Society of Hematology (ASH) 2022 guidelines for the diagnosis and management of autoimmune hemolytic anemia · British Society for Haematology 2017 guidelines on the diagnosis and management of warm and cold autoimmune haemolytic anaemias · UpToDate: Diagnosis and treatment of warm autoimmune hemolytic anemia (2023) · Blood (journal): Consensus recommendations for the diagnosis and treatment of autoimmune hemolytic anemia (Hill et al., 2023) · reviewed 2026-08-29