Paroxysmal Nocturnal Hemoglobinuria: From Bench to Bed

Area of Science:

• Hematology
• Genetics
• Immunology

Background:

• Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematopoietic stem cell disorder.
• It is characterized by complement-mediated destruction of blood cells due to deficiency of glycosylphosphatidylinositol (GPI)-anchored proteins like CD55 and CD59.
• The genetic basis involves mutations in the PIGA gene, leading to GPI anchor deficiency.

Approach:

• This overview discusses the pathophysiology of PNH, focusing on the role of the complement system.
• It highlights the clinical manifestations, including hemolytic anemia, thrombosis, and organ damage.
• The therapeutic strategy involves inhibiting the terminal complement cascade.

Key Points:

• PNH diagnosis and outcome prediction are challenging due to variable clinical presentations.
• The disease results from a PIGA gene mutation in hematopoietic stem cells, causing GPI-deficient cells.
• Clinical features stem from complement-mediated hemolysis and free hemoglobin release.

Conclusions:

• Understanding PNH pathophysiology is crucial for managing clinical symptoms and complications.
• Inhibition of the terminal complement cascade offers an effective treatment strategy for PNH.
• This review aims to provide a comprehensive overview for clinicians managing PNH patients.