10 Intrinsic Hemolysis

PNH

Cause

• normally complement does not lyse RBC

• acquired: genetic mutation some point in life

• GPI: anchors that attach DAF/CD59 to membrane

• stem cell: RBC, platelets, WBC also involved

Pathogenesis, Symptoms

• Free plasma Hgb thrombogenic, thrombosis

• platelets lysed: spill granules

• Priapism: sustained prolonged erection

• paroxysmal: sudden

• episodes at night when urine changes color

• hypercoagulable

Diagnosis, treatment

• antibodies not part of problem

Pyruvate Kinase Deficiency

• when levels low, RBC most affected (require pyruvate kinase and glycolysis for anerobic)

• no ATP, membrane fails

• when problem with membrane, eaten in spleen

• disease severity based on how low enzyme activity is

G6PD Deficiency

• especially fava beans

• antimalarials can trigger hemolysis

• know the countries

• Can't make ATP, RBC become rigid, cannot maintain membrane

• most extravascular

• some become so damaged/rigid: intravascular

• Bite and seeds: bite cells and Heinz bodies seen in RBCs

• Broken G6PD-free fruit: hemolytic anemia in G6PD deficiency

• Bite and seeds: bite cells and Heinz bodies seen in RBCs

• Broken G6PD-free fruit: dapsone can cause hemolytic anemia in G6PD deficiency

• "Color queen" - chloroquine, beads join together as polymer, blocking plasmodium heme polymerase. High resistance

• "Primal queen" - primaquine, can cause anemia in G6PD deficiency

• fluorescent spot: screening test

• pts unable to generate NADPH

• normal: generate NADPH, fluoresce

• must test when not having acute attack

Hereditary Spherocytosis

• proteins give RBC biconcave shape and flexibility

• abnormal: rigid membrane

• spectrin for spherocytosis

• problem lies in chronic extravascular hemolysis, not O2 carrying capacity

Diagnosis

• progressive loss of cell membrane as RBC circulate in vasculature

• RDW: red cell distribution width

• normally: narrow, some small/large cells. Most are in middle

• Spherocytosis: large spectrum of RBC sizes

• material density goes up

• MCHC: mean corpuscular hemoglobin concentration

• MCV: mean corpuscular volume: average size of RBCs

• chronic hemolysis: more reticulocytes, high MCV

• viscosity of blood go up with rigid cells

• no spherocytes in G6PD with infection