71 terms

HemOnc Anemias

RBC maturation in Blood
reticulocyte and erythrocyte
RBC Studies
RBC count, Hemoglobin, Hematocrit (packed cell volume)
RBC indices
Reticulocyte count
indication of hematopoetic/bone marrow activity, norm range 0.5-1.5%
RBC distribution width, measurement variation in size of RBCs, normal 11-14%, Increased in Vit B12 deficiency, folate deficiency, IDA, Normal in acute blood loss
Basophilic stippling
lead poisoning
T/F anemia is a disease of blood delivery to O2
False. Not a disease or diagnosis in itself but a manifestation of underlying disease
Anemia problem
A decrease in ability of blood to deliver O2 to peripheral tissues resulting in tissue hypoxia
Adequate RBC production requirements
iron, vit B12, and folic acid; hemoglobin synthesis must also function normally
Causes of anemia
Acute bleeding, decrease production of RBCs, increased destruction of RBCs
Normocytic, normochromic anemia
anemia of chronic dz, acute blood loss
Microcytic, hypochromic
Iron deficiency anemia, thalassemias, sickle cell, chronic blood loss
Macrocytic (megaloblastic) anemias
Vit B12 deficiency/pernicious anemia, Folate deficiency, chemotherapy, liver dz
Most common anemia in US
Iron deficiency anemia
Iron absorption
In duodenum and proximal jejunum, enters bloodstream and binds to transferrin, taken to bone marrow to be incorporated into hgb, Stored in liver as ferritin and hemosiderin
Iron Deficiency anemia definition
A decreased total body iron content
Etiologies of IDA
Bleeding, dietary, malabsorption, sources of loss include GI, gyne, urinary tract, lung & skin
IDA clinical findings
fatigue, pallor or mucus membranes, glossitis, angular stomatitis, atrophic gastritis, spooning of nails, pica in severe disease
Lab studies in IDA
Decreased H/H, MCV and MCHC, iron and ferritin levels, transferrin saturation, reticulocytes early, increased TIBC
Most sensitive way to diagnose IDA
Serum ferritin level more sensitive and reliable way to diagnose IDA than serum Fe and TIBC
Treatment of IDA
Iron replacement FeSO4 325mg PO TID or IV, IM. Usually need to continue tx 3-6months after improvement to replete Iron stores and prevent relapse
Pernicious anemia
A megaloblastic anemia from low vit B12 levels (cyanocobalamin), Intrinsic factor is necessary to absorb B12, autoimmune disease due to abs directed against parietal cells or intrinsic factor
Other etiologies of Vit B12 Deficiency
dietary deficiency, gastrectomy, pancreatic insufficiency, Zollinger-Ellison dz, Bacterial overgrowth in intestine, Fish tapeworm, blind loop syndrome
Pernicious anemia Findings
Fatigue, pallor, anorexia, smooth/beefy red/sore tongue, diarrhea or constipation; neuro- paresthesias and balance problems. Severely low B12 levels lead to dementia and neuropsychiatric disturbances
Pernicious anemia lab studies
Decreased H/H, increased MCV, Howell-Jolly bodies in RBCs, may see hypersegmented neutrophils on smear, low Vit B12 level, parietal cell or intrinsic factor antibodies, Positive Schilling's test
Howell-Jolly bodies
Pernicious Anemia
TX of pernicious anemia
Give Vit B12 100-1000mcg IM QD 1wk, then Qwk 5-6wks, then Qmo; usually better in days and hematologically normal in ~2mos
Folic Acid deficiency
megaloblastic anemia, most frequently caused by inadequate intake (especially alcoholics)
Folic acid sources
green, leafy vegetables, liver, meats & some fruits, esp oranges and their juice
Etiologies of Folic acid deficiency
dietary deficiency, malabsorption, dialysis, folate antagonists, chronic hemolysis
Sx of Folic acid deficiency
Same as Vit B12 except NO neurological symptoms
Anemia of chronic disease
Mild normochromic/normocytic anemia initially, if persists become microcytic/hypochromic, most common type of anemia encountered among hospitalized pts
Etiologies of ACD
Chronic infection or inflammation, malignancies, chronic liver dz, ETOHism, chronic renal disease, endocrinopathies
ACD Labs
Normal MCV, MCHC, decreased Fe, Normal or increased ferritin, decreased or normal TIBC; new test hepcidin level increased
Hemolytic anemia
Congenital or acquired causes damage to RBC membrane leading to destruction of RBCs intravascularly or in macrophages of spleen or liver
Hemolytic anemia causes
immune system, chemicals, drugs, burns, venoms, thermal injury, RBC membrane defects, RBC enzymopathies, microorganisms and RBC destruction by passing thru fibrin threads
Autoimmune hemolytic anemia (AIHA)
due to cold agglutinins or warm-reactice Abs, Cold AIHA may be caused by infections, B cell malignancies; Warm AIHA may be caused by leukemias, lymphomas, myeloma, SLE and other autoimmune dzs, UC, viral infxns
Labs for Hemolytic anemia
Positive Coomb's test; increased retics, bilirubin, and urobilinogen; decreased haptoglobin, increased LDH; may see bizarre shapes and nRBCs on smear
Tx for hemolytic anemia
Treat underlying condition, steroids may be effective, RBC transfusion if markedly anemic, if cold AIHA avoid cold, if warm AIHA and no response to tx may need splenectomy
Microangiopathic hemolytic anemia
Mechanical chewing of RBCs, see abnormal RBC shapes on smear, caused by DIC, TTP, HUS, disseminated CA, PVD, scleroderma and collagen vascular dz and eclampsia or from mechanical heart valves and external trauma
RBC membrane defects
Hereditary spherocytosis, hereditary elliptocytosis, stomatocytosis, and xerocytosis
Hereditary spherocytosis
autosomal dominant D/O more common in northern Europeans caused by spectrin/ankyrin deficiency of RBC membrane causing fragility then spherocytes and hemolytic anemia
Glucose-6-Phosphate dehydrogenase Deficiency (G6PD)
X-linked recessive hereditary dz; G6PD important enzyme in RBC metabolism. More common in African, middle eastern, and south asians. Develop non-immune Hemolytic anemia to triggers.
Linked to favism
Sickle Cell Anemia
Autosomal recessive d/o where Hgb S leads to hemolytic anemia and other problems; 8% of African-americans carry the gene
Sickle Cell Patho
when deoxygenated Hgb S forms polymers that damage RBC membrane. Hgb F retards process, Hypoxemia and acidosis worsen sickling
Sickle Cell onset
Onset in 1st year of life when Hgb F falls and Hgb S rises; hypoxemia and acidosis worsen sickling
Sickle Cell symptoms
hemolysis, jaundice, splenomegaly, gallstones and slow healing ulcers on leg; PAIN, Death is from organ failure and infection
Pain in Sickle Cell disease
Sickle cells occlude vessels causing infarction; affects bones, abdomen, chest and brain; priapism may occur
Autosplenectomy in sickle cell
Abnormal RBCs pool in spleen and undergoes repeated infarction that enlarges and function impaired then becomes fibrotic and shrinks, nonfunctioning spleen cannot filter/catch encapsulated organisms
Essentials to Diagnose Sickle Cell
Sickled RBCs on smear, +FH and lifelong hemolytic anemia, recurrent painful episodes, finding Hgb S on electrophoresis
Sickle Cell anemia Labs
Decreased MCV and MCHC, increased reticulocytes, Hemoglobin electrophoresis establishes dx, Howell-Jolly bodies and target cells, Nucleated RBCs
Tx of sickle cell dz
Primarily supportive (pain control, IV fluids, pnumococcal vaccine in childhood), treat complications, blood transfusion in crisis, Hydroxyurea increases Hgb F and decreases vaso-occlusive crises and painful episodes
Sickle Cell Trait
Clinically normal, Have 1 gene for formation of Hgb S & 1 gene for formation of normal Hgb; only symptomatic under extreme conditions (high altitudes, dehydration, extreme heat), Counseling for reproduction is needed, May protect against malaria
Inherited group of anemias caused by absent or defective synthesis of one or more of the globin chains leading to defective Hgb production and damage to RBCs or their precursors by build-up of globin chain produced in excess
Thalassemia names
Named according to chain with reduced or absent synthesis (either alpha or beta of Hgb A)
Beta thalassemia major
AKA Cooley's anemia, most common in Mediterranean descent, no Beta chains produced. Physical growth and development delayed. Severe, transfusion dependent
Beta thalassemia major labs
decreased MCV, MCH and H/H but normal or increased RBC count, severe poikilocytosis and nRBCs on smear
Beta Thalassemia major in childhood
Fatal in late childhood and early adolescence as iron overload results from hypertransfusion and organ toxicity
Tx of Beta Thalassemia major
Need iron chelation (deferoxamine); may extend life to 4th decade, possible bone marrow tx
Beta thalassemia trait
decreased but not absent Beta chains; mild, asymptomatic hemolytic anemia; still have significant microcytosis/hypochromia with some poikilocytosis normal Fe studies
Alpha thalassemia
decreased or absent production of alpha chains, alpha syndromes depend on # of a alpha globin genes that are deleted; more common in chinese and southeast asians
Aplastic anemia
deficiency of hematopietic cells resulting in severe hypoplasia of bone marrow and pancytopenia; cause idiopathic but may be due to hereditary or exposure to drugs, infxns, chemicals, radiation
Aplastic anemia Labs
decreased WBCs, platelets, and RBCs; RBCs usually normocytic/normochromic but may be macrocytic; bone marrow aspirate shows hypocellularity
Anemia of pregnancy
From end of 1st trimester til ~20th week, there is progressive decrease in RBCs and H/H. Dilutional due to increase plasma volume versus a smaller increase in RBC mass. No tx needed
Sideroblastic anemia
Decreased Hgb synthesis secondary failure to incorporate heme into protoporphyrin to from Hgb; iron accumulates in RBC precursors in BM
Causes of Sideroblastic anemia
Often caused by chronic ETOHism, drug toxicity, and lead poisoning
Lead poisoning finding in RBCs
basophilic stippling
Labs of sideroblastic anemia
basophilic stippling of RBCs, increased serum iron, ferritin, and transferrin saturation, decreased TIBC; BM aspirate shows increased erythroid hyperplasia with ringed sideroblasts on Prussian blue stain
Packed RBCs
pRBCs used to correct for significant anemia, some pts require leukocyte-reduced pRBCs as WBCs are most common cause of febrile transfusion rxns
Most common transfusion rxn
Febrile nonhemolytic transfusion rxn due to small amount of WBCs in each unit of pRBCs