Exam 3 Hematologic Slide Set 2 Flashcards
1
Q
Diagnosis of Autoimmune Hemolytic Anemia (AIHA) (Extrinsic Hemolytic Anemia)
A
Coomb’s & Indirect Coombs antiglobulin test
- detection of antibodies or complement is required to dx.
2
Q
Warm Ab AIHA
A
- Mot common form of AIHA
- 50% idiopathic
- 50% secondary to SLE or neoplastic dz (eg lymphoma)
- IgG* is most common (IgA second)
3
Q
Cold agglutinin AIHA
A
- IgM Abs bind to RBCs at low temperatures (0-4 C)
- IgM agglutinates & fixes Complement to the surface of the RBC
- 15-30% of these anemias
- Abs appear acutely during recovery from infections (Mono, HIV, Flu, etc) -> self-limiting & rarely causes clinical manifestations
- Will occur chronically idiopathically or in response to some lymphoid neoplasms
- > Raynaud phenomenon
4
Q
Hemolytic Anemias (Extrinsic) resulting from Trauma
A
Causes: cardiac prosthesis, narrowing of microasculature (DIC), SLE, malignant HTN, TTP, HUS, cancer.
- Mechanical injury to RBC
- Peripheral smears show RBC fragments (schistocytes, burr cells, helmet cells
- TTP and HUS are the only conditions that cause major clinical problems associated with hemolysis
5
Q
Anemias of Diminished Erythropoiesis
A
- Megaloblastic (deficiency) anemias
- Iron Def Anemia
- Anemia of chronic dz
- anemia of renal failure
- marrow stem cell failure (aplastic anemias)
6
Q
Megaloblastic (macrocytic) anemias
A
- B-12/folate deficiency (leads to inadequate thymidine) -> megaloblastic changes in all rapidly dividing cells -> b/c RNA synthesis is unaffected
- Inadequate diet & alcoholism
- Impaired DNA synthesis & distinctive morphological changes in the blood & bone marrow*
- TPN/PPN, Azotemia/Uremia, Bacteremia/Septicemia?
7
Q
Causes of Folic Acid Deficiency
A
-Alcoholism
-Phenytoin Sodium (anti-seizure medication)
-Anti-Metabolites (cancer drugs)
-HIV/AIDS drugs
(So… only things we do on purpose)
8
Q
Morphological presentation in Megaloblastic anemia
A
- RBC size & MCV increased
- Anisocytosis (increased RDW)
- Eosinophils & Neutrophils have hypersegmented nuclei
- Low reticulocytes, some nucleated RBCs present in severe cases
- Marrow is hyper cellular with increase in all myeloid precursors.
9
Q
Pernicious anemia (cause, associations, populations affected, dx)
A
- Lack of Intrinsic Factor leads to inadequate absorption of B-12
- Assoc. w/gastric atrophy & achlorhydria, both often
- Assoc. w/H pylori infection has NOT been proven yet
- Pernicious anemia pts have 2-3x increase incidence of gastric carcinoma
- Coexisting iron deficiency common b/c achlorhydria prevents getting ferric iron from food
- Adult pernicious anemia most common in Celtic (English, Irish, Scottish) or Scandanavian origin
- 10-20 cases/100,000 people/year
- Does it all begin with auto reactive T-cell response that targets gastric mucosa???
- *Gold standard dx = biopsy of gastric mucosa showing depleted parietal cells.
10
Q
Antibodies found in pernicious anemia
A
- Type 1 blocks binding of B-12 to IF
- Type 2 blocks binding of IF/B-12 combo to its ileal receptor
- Type 3 binds to proton pump, found in 50% of elderly patients with chronic gastritis
- Anti-parietal cell Abs occur in 90% of pts with pernicious anemia and only 5% of healthy individuals
- *Gold standard dx = biopsy of gastric mucosa showing depleted parietal cells.
11
Q
Pernicious anemia morphology
A
- Changes in marrow, alimentary tract, and NS
- Alimentary tract = stomach & tongue: glossitis, intestinization (gastric epithelium replaced by goblet cells ie metaplasia)
12
Q
General/other sx of B12 deficiency
A
- NS sx in absence of anemia (more common in its taking folic acid or high-folate diet)
- Older pts may present with dementia/Alzheimers sx: memory loss, irritability, personality changes
- Megaloblastic madness: delusions, hallucinations, outbursts, paranoid schizophrenic ideation (myelin los in nerves of the posterior column)
13
Q
Diagnostic features of B12 deficiency
A
-low serum RBC & B12, hgb, hct
-MCV elevated
WBC & platelets decreased
Increased homocysteine & methylmalonic acid (risk factors for atherosclerosis & thrombosis)
-Mild jaundice from ineffective erythropoesis & hemolysis
-**Inability to absorb oral B12 supplementation*
14
Q
How does one become deficient in folate?
A
- Poor diet (poor, elderly, those who don’t eat… green leafy vegetables, lemons, bananas, melons, yeast & liver!) or eat too much overcooked food.
- *It’s not stored in the body
- Interfering medications: dilantin, lithium, sulfasalazine, oral contraceptives
- Also: alcoholism, hx of malabsorption, & pregnancy
- US 4/100,000ppl have folate deficiency
15
Q
Morphological presentation of folate deficiency
A
- Megalocytes (circulating) & Megaloblasts (BM)
- Hypersegmented neutrophils
- Decreased serum folate or RBCs
- Elevated serum homocysteine
16
Q
Break it down - 3 major causes of folate deficiency
A
- Decreased Intake: diet/absorption, alchoholism, drugs
- Increased requirement: pregnancy, infancy, hemolytic anemias, cancer
- Impaired use: folic acid antagonists, ie drugs
17
Q
General/other ramifications of Folate deficiency
A
Pregnant women -premature birth -neural tube defects -placenta previa Infants -low birth wt -spina bifida -cleft lip -cleft palate
18
Q
IDF
A
- most common def in world: lack, absorption, requirement, blood loss
- Common in developing countries -> vegetarian diet
- Increased requirement in: infants, children, adolescents, menstruating women & pregnant women. Also when you have multiple/frequent pregnancies.
19
Q
Impaired iron absorption is found in these dz’s/conditions
A
- Celiac
- Other malabsorption causes (helpful!)
- Chronic diarrhea
- **And gastrectomy b/c that’s when the iron absorbing starts HCL + duodenum are really helpful
- Chronic blood loss is the most common cause of IDF in the western world. (Gi, Gu, GYN!)
20
Q
IDA - iron deficiency anemia
A
- microcytic/hypochromic
- In: depleted stores, low serum iron, low serum ferritin, low transferrin saturation
- Presentation: Koilonychia (concave nails), alopecia, atrophic changes to tongue, gastric mucosa, and intestine. Smear shows the lil’ cells & pencil/cigar cells or elliptocytes.
- *disappearance of stainable iron from mononuclear phagocytic cells in the marrow is diagnostically significant.
21
Q
Dx of IDA
A
- low ferritin
- low iron
- Elevated TIBC
22
Q
Anemia of Chronic Dz (ACD) - 3 C’s
A
- Chronic infections (lung abscess, bacterial endocarditis, osteomyelitis)
- Conective tissue dz (RA, SLE, Chron’s)
- Cancer (Hodgkin lymphoma, lung/breast cancer and other CA)
- Shows low iron AND low TIBC with normal or elevated ferritin!! B/c the little pin protein is doing stuff)
- hypoproliferative anemia that is normocytic/normochromic, but if associated w/IDA it can be micro/hypo.
23
Q
Aplastic Anemias
A
- The failure of pluripotent stem cells to produce RBCs, WBCs, and megakaryocytes
- Morbidity/mortality usu from infection & bleeding
- Sx: usual anemia & thrombocytopenia -> mucosal/gingival bleeding, petechial rash. Neutropenia -> infections
- Bone marrow failure syndrome: PB pancytopenia or BM hypoplasia.
- BM devoid of hematopoetic elemetnts, may show fat cells, fibrous stroma, or scattered foci of lymphocytes & plasma cells.
- Result of T cells suppressing STEM cell fxn after exposure to drugs, infectious agents, or environmental toxins
- 80% acquired, 20% congenital
24
Q
Acquired aplastic anemia (80%) causes
A
- Infectious dz (EBV, HIV, hepatitis, etc)
- Toxic exposure (radiation, benzene)
- Drugs (chloramphenicol, sulfa, gold)
- Idiopathic!
25
The microcytic hypochromic anemias
- IDA
- Lead poisoning
- Thalassemia
- Hypothyroidism
- ACD
26
The macrocytic anemias
- B12 def
- Folic acid def
- EOH abuse
- Hyperthyroidism
27
The normochromic normocytic anemias
- acute hemorrhage/lysis
- aplastic anemia
- hypothyroid
- ACD
- vampires!
