Overview
Definition
Acquired stem cell defect causing complement-mediated RBC destruction.
Epidemiology
Varies globally depending on genetics, environment, or exposure.
Etiology & Risk Factors
- Somatic mutation in PIGA gene (absence of CD55/CD59).
Clinical Symptoms
- Episodic dark morning urine (hemoglobinuria)
- fatigue
- venous thrombosis (Budd-Chiari).
Clinical Approach
Diagnosis
- Flow cytometry (absence of CD55/CD59).
Management
- Eculizumab (complement inhibitor).
Complications
- Massive thrombosis
- Leukemia transformation.