autoimmune, immunologic, and hereditary

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autoimmune hemolytic anemia

antibodies directed against a person’s own RBCs cause them to lyse

autoimmune hemolytic anemia pathophys

acquired destructive disorder in which IgG autoantibody is formed that binds to RBC membrane protein

autoimmune hemolytic anemia causes

usually idiopathic, can be infective, autoimmune, pregnancy, lymphoproliferative, immunodeficiency

autoimmune hemolytic anemia diagnosis requirement

must distinguish from drug induced hemolytic anemia

autoimmune hemolytic anemia CP/PE

anemia of RAPID onset, fatigue, dyspnea, jaundice, splenomegaly

maybe angina pectoris, hepatomegaly

autoimmune hemolytic anemia dx labs

low hgb, haptoglobin

high reticulocytes, indirect bilirubin, LDH

positive coombs test

coombs test

detects antibodies that attack red blood cells

haptoglobin

binds free hemoglobin and prevents toxicity, acute phase protein, would be low in hemolytic anemia

autoimmune hemolytic anemia medications tx

1st line - predisone 1-2mg/kg/day for several weeks with slow taper

rituximab IV x4 weeks, danazol, folic acid

autoimmune hemolytic anemia non meds tx

packed cells (hard to match, don’t survive well), plasmapheresis, splenectomy, treat underlying condition

autoimmune hemolytic anemia pt ed

hematology referral, likely to relapse, prognosis is good long term

immune thrombocytopenic purpura

autoimmune condition with pathogenic antibodies binding platelets and accelerating their clearance from circulation

immune thrombocytopenic purpura populations

(MC) kids - follows infection

adults - underlying disorder triggers it

immune thrombocytopenic purpura categories

primary idiopathic and secondary

secondary immune thrombocytopenic purpura causes

many autoimmune conditions, MMR vax, h. pylori, HIV, HCV, CMV, VZV, covid

platelet lifespan

1 week

immune thrombocytopenic purpura patho

immune mediated destruction of platelets

antiplatelet ab targets some glycoproteins on platelet membrane

immune thrombocytopenic purpura CP/PE

bruising, epistaxis, petechiae, bleeding gums

maybe mucocutaneous bleeding (plt <10-20)

immune thrombocytopenic purpura dx

CBC with low plt, all else normal

evaluate for secondary causes (viruses, etc)

immune thrombocytopenic purpura tx threshold

plt <25-30 or significant bleeding

immune thrombocytopenic purpura tx

prednisone 1 mg/kg x10-14d then taper

immune thrombocytopenic purpura alternative tx

IVIG 1-2g/kg IV - EXPENSIVE

plt transfusions, rituximab

immune thrombocytopenic purpura outpatient tx indication

no significant bleeding/signs of impending bleeding, plt >5

immune thrombocytopenic purpura inpatient tx indication

bleeding, plt <5

immune thrombocytopenic purpura pt edu

treat underlying infxn, good response to steroids, hematology referral, BE CAUTIOUS

pernicious anemia

rare autoimmune disorder with fundic glands with achlorhydria (little to no HCl prod), decreased IF secretion, and B12 malabsorption

pernicious anemia pathophys

autoab target IF and gastric parietal cells

pernicious anemia population

northern europeans, mostly 70-80 y/o, MC in pts with other autoimmune diseases

pernicious anemia CP/PE

fatigue, lightheadedness, pallor, neuro sx, SOB, glossitis, muscle wasting, weight loss

pernicious anemia dx

CBC w/macrocytic anemia (hgb <4), anti IF ab

low B12

high MMA

pernicious anemia gastric biopsy results

atrophy of all layers, loss of glands, absence of parietal/chief cells, maybe h. pylori hx

pernicious anemia screenings

EGD/colonoscopies (3x risk of GI malignancy)

pernicious anemia tx

B12 supplement, usually lifelong

diet mods

pernicious anemia pt edu

elevated risk of gastric cancer

sx: worsening heartburn, bloody/black stool, unexplained weight loss, decreased appetite

pernicious anemia referral

GI for EGD/colonoscopy

what can be transfused

whole blood, packed cells, platelets, FFP, cryoprecipitate

packed cells transfusion indication

hgb <8 in cardiopulmonary pts

hgb <7 all others

packed cells transfusion cautions

volume, speed, consider special orders

packed cells transfusion benefit

1 decimal point bump in hgb

type and hold

blood type and put in file

type and cross

patient needs blood so pt’s blood is tested and cross tested for matching

type and cross length of accuracy

72 hours

type and hold length of accuracy

30 days

expiration time for blood products

4 hours

special transfusion orders

leukocyte poor, irradiated, CMV negative

platelet transfusion indication

if getting invasive procedure - <50

normal pts - <10

priority transfusion - <5

platelet transfusion cautions

truly necessary?

more transfusions = more sensitized

HLA match

human leukocyte antigen matching

identifying compatible tissue types between a donor and recipient

FFP transfusion indications

factor deficiencies, liver disease

FFP transfusion contraindications

to reverse warfarin

cryoprecipitate transfusion indication

fibrinogen disorders, von willebrand disease (VWD), disseminated intravascular coagulation (DIC), uremic bleeding

transfusion reaction

adverse event that can occur during or after blood product transfusion, more common with platelets

transfusion reaction common types

allergic, febrile nonhemolytic transfusion reaction (FNHTR), transfusion associated circulatory overload (TACO)

febrile nonhemolytic transfusion reaction

cytokine release from wBC in unit

chills, rigor, fever

febrile nonhemolytic transfusion tx

acetaminophen, stop transfusion

allergic transfusion reaction

plasma from donor reacts with pre-existing IgE ab

urticaria

allergic transfusion reaction tx

benadryl, continue transfusion

uremic bleeding populations

renal/dialysis pts

anaphylactic transfusion reaction

product contains substance to which the pt is allergic

dyspnea, coughing, N/V, hypotension, respiratory arrest

anaphylactic transfusion reaction tx

stop transfusion ASAP, epi, steroids

acute hemolytic transfusion reaction

ABO mismatch

hypotension, tachypnea, tachycardia, fever, chills, chest/flank pain

acute hemolytic transfusion reaction tx

stop transfusion ASAP, IV fluids

not really transfusion reactions

fluid overload, hypothermia, electrolyte issues, iron overload

transfusion associated circulatory overload

respiratory distress, evidence of pulmonary edema, elevated BNP, other unexplained cards changes

transfusion associated circulatory overload population

CHF patients and increased transfusion

transfusion associated circulatory overload tx

oxygen, diuresis, ventilatory support

transfusion related acute lung injury

MC with platelets

hypoxia, bilateral infiltrates, some with fever/hypotension

transfusion related acute lung injury tx

stop transfusion, supportive care

progression of transfusion reactions over time

anaphylaxis → allergic → acute hemolytic tfn rxn → febrile non hemolytic tfn rxn → tfn related acute lung injury

calcium citrate in blood consequence

numbness/tingling around mouth

hemochromatosis

autosomal recessive disorder leading to iron overload

who to call with transfusion reaction

lab/blood bank

hemochromatosis genes

MC HFE gene homozygous for C282Y mutation

homozygote C282Y hemochromotosis population

up to 50% devel iron overload, usually men since women rid iron with menses, typically over 30 y/o

hemochromatosis pathophys

HFE protein plays role in which duodenal crypt cells sense iron body stores leading to increased iron absorption from duodenum, decreased synthesis/expression of hepcidin, iron accumulates

hemochromatosis iron accumulation locations

liver, pancreas, heart, adrenal glands, testes, pituitary gland, kidneys

hemochromatosis CP/PE

typically age 50+, fatigue, arthralgia, arthropathy, hepatomegaly, bronze skin, cardiomegaly, diabetes, ED, jaundiced especially in eyes

vital sign interval for transfusion

time 0, 15 mins, and at end

hemochromatosis dx labs

mildly abnormal liver tests

high iron, ferritin, % saturation

low TIBC

positive HFE mutation

hemochromatosis dx non labs

MRI, liver biopsy for cirrhosis

hemochromatosis tx

phlebotomy, supportive care to damaged organs, liver transplant, chelation (?) with deferoxamine

hemochromatosis phlebotomy tips

1 unit of blood = 250mg Fe, need to remove 25g

done weekly x1-2 years or less often for maintenence

PPI can reduce iron more

hemochromatosis pt edu

avoid iron rich food, screen family members

hemoglobin A

normal adult hemoglobin, tetramer of 2 alpha globin chains and 2 beta globin chains

95-98% of circulating hgb

hemoglobin A2

2-3% of circulating hgb

hemoglobin F

50-80% in newborn

8% in 6 month old

0.8-2% of adults

hemoglobin S

not normally present, can indicate sickle cell

sickle cell disease

inherited RBC disorders that cause RBCs to become misshapen and break down

autosomal recessive disorder with hgb SS leading to chronic hemolytic anemia

sickle cell anemia gene

homozygous for hgb S

sickle cell trait gene

heterozygous for hgb S

sickle cell trait

benign carrier state of SCD, usually don’t show manifestations of disease

theoretically protective against malaria due to RBC shape

sickle cell disease mutation causes…?

hfb molecule stacks and forms polymer when deoxygenated and RBCs become rigid

RBC changes in sickle cell disease

membrane changes, interaction with WBC, hemolysis, nitric oxide depletion, release of inflammatory proteins, coagulation

hemochromatosis liver transplant benefit

previous liver is reason for disease due to lack of hepcidin so new liver means very low likelihood of recurrence

sickle cell disease severity

varies a lot

hgb F causes antisickling

alpha thalassemia decreases severity

sickle cell disease population

8% of Black americans

homozygous sickle cell disease prognosis

life expectancy <50, very morbid disease manifests as sickle cell crisis

sickle cell disease CP/PE

chronically ill appearing, hemolytic anemia, jaundice, pigment gallstones, poorly healing skin ulcers over tibia, EXTREME PAIN, hepatomegaly, maybe splenomegaly, cardiomegaly

hemochromatosis screening

unexplained liver disease, chondrocalcinosis, ED, T1D

sickle cell crisis types

veno occlusive, aplastic, sequestration, hyperhemolytic