Table 1.

Clinical categories of patients with PNH clones

PNH category	PNH granulocyte clone	Clinical hemolysis	Laboratory markers of hemolysis	PNH symptoms	Risk of thrombosis	Utility of complement inhibitor therapy
Bone marrow failure with an associated PNH clone
Subclinical (majority of patients)	Small (usually <30%)	Absent	May be present, depending on clone size	Absent	Low	Do not benefit from complement inhibitor
Symptomatic	Moderate	May be present	May be present	May be present	Intermediate	Some patients may benefit from complement inhibitor
Classical PNH	Large (usually >50%)	Present	Present	Present	High	Complement inhibitor improves outcomes