unit 2 hem summer

rbc main job

produce ATP, protect hgb, regulate O2 delivery

embden-meyerhof pathway EMP

anaerobic glycolysis using 90-95% of available glucose, producing 2 atp, 2 nadh, 2 pyruvate

pyruvate and NADH in rbc

lactate fermentation generating NAD+ catalyzed by LDH

atp

energy for iron pumps, maintains cell volume, membrane flexibility and deformability

NADH

electron carrier produced during glycolysis, regenerated to NAD+ during lactate fermentation to continue glycolysis

pyruvate

end prodduct of glycolysis, converted to lactate in rbc by lactate fermentation asap

without atp

ion homeostasis disrupted, membrane becomes rigid, hemolysis is likely, can cause pyruvate kinase deficiency

pyruvate kinase deficiency

rigid cells cannot fit through narrow splenic cords, splenic macrophages phagocytose rbc, causes chronic extravascular hemolytic anemia

hexose monophosphate path HMP or PPP

uses 5-10% of available glucose in rbc to produce NADPH, keeps glutathione in its reduced form protecting hgb from oxidative damage, can cause G6PD def

G6PD defic

first enzyme of HMP, low NADPH causing no reduction of glutathione, oxidants denature hgb (Heinz bodies)

Heinz bodies

clumping of denatured hgb stuck to inside of rbc membrane causing low membrane deformability, splenic macrophages BITE, extravascular hemolysis (hemolytic anemia), use Supravital stain

MetHgb reduction pathway

maintains ferrous Fe2 by using cytochrome b5 reductase and NADH to reduce Fe3 to Fe2 (this NADH is from EMP)

cytochrom b5 reductase def

low cytochrome b5 reductase activity, MetHgb accumulates, reduced oxygen delivery to tissues, methemoglobinemia causing cyanosis

Rapoport-Luebering pathway

branch of EMP with less ATP production, produces 2,3-BPG or 2,3-DPG, binds to center deoxyhgb, stabilizes quaternary structure, decreasing hdg affinity for O2, and promoting ox release to tissue RIGHT shift

2,3-BPG increase

low O2 affinity high unloading, right shift, high altitude, anemia, chronic hypoxia COPD

2,3-BPG low

high O2 affinity low unloading, left shift, stored blood (improves after transfusion), hgb F

rbc are removed when

they cannot repair themselves, atp and enzyme levels gradually decline, membrane fragments are lost, cells become less deformable

extravascular hemolysis

abt 90% of destruction of old or abnormal rbc in spleen, liver, bm by macrophages that conserve and recycle post phago components

intravascular hemolysis

abt 10% of destruction of rbcs inside bv by cell lysis in circulation, releases hgb into plasma low hapt, usually pathologic (Hemoglobinuria)

splenic functions

culling- removes old rigid rbc, pitting- removes inclusions, filters ab-coated rbcs, stores 1/3 of the bodys platelets

hgb- globin

broken down AAs, recycled into new proteins

hgb- iron

stored as ferritin or hemosiderin, transported by transferrin, reused for hgb synthesis

hgb- heme

broken down to unconjugated bili binding alb in bloodstream, conjugated in liver, bile duct excretes it into intestines as urobilinogen, excreted by kidneys or stool as urobilin and sterco bilinogen, some returns to liver

haptoglobin

hgb scavenger, binds free hgb, complex recycled in liver, large amounts of hemolysis when hapt is used up increasing free hgb in urine (hemoglobinuria)

routine hem testing types

complete blood count CBC (peripheral smear/ manual differential), reticulocyte count (retic), spun hematocrit (microhematocrit, hct), erythrocyte sedimentation rate ESR

routine testing ref ranges

vary from lab to lab, age, sex, altitude / environment, testing methodology

CBC

most common hemo test (screen diagnose monitor), rbc wbc plt

normochromatic and normocytes

normal staining, normal MCH and MCHC

polychromatic

more purple, longer, rna, anemic, MCV normal to high

hypochromasia

pale, larger central palor, low MCH and MCHC

hyperchromasia

no pallor (spherocyte), deep dye, high MCHC

normocyte

7-8 um (size of nucleus of resting lymphocyte), normal MCV

anisocytosis

variable size, high RDW

microcyte vs macrocyte

small, low MCV vs big high

poikilocytosis

large variation in one shape or many shapes

spherocytes

spherical, no pallor, smaller, if lots high MCHC

elliptocytes vs ovalocyte

skinny oval, hereditary elliptocytosis vs oval , iron def anemia, more common

stomatocytes mouth

uniconcave (only half depressed)

schistocytes and helmet cells

fragment cell vary, smaller

acanthocyes vs echinocytes burr

irregular spikes vs uniform spikes, artifacts

target cells

hgb in pallor, bulls-eye, spleen issue

teardrop or dacrocyte

pear tear shaped, squeezed by spleen

sickle cells

crescent, point ends, drepanocyte

bite cell vs blister cell

bigger than schistocytes vs half ghost looking

nRBC

retained nucleus , blue-purple

howell jolly bodies vs pappenheimer bodies vs basophilic stripping

single round nuclear remnants, show in wrieght-stain, vs lump of iron, blue purple, more than one and less round vs dark inclusions of ribosome remnants cover cell

malaria vs babesia

2 rings vs 1 ring think abt location