Hematology 1 Flashcards
What are 4 possible mechanisms of developing anemia?
Blood loss (acute or chronic)
Decreased absorption
Deficient erythropoesis
Excessive Hemolysis
What are some risk factors of anemia?
dietary deficiencies, menstruation, gastric ulcer, blood in stool, pregnancy, lactation, hemoglobinopathies, alcoholism, prescription drugs, cancer, rheumatic disorders, chronic inflammatory disease, COPD, CHF, heart disease heart valve, marathon running
What are symptoms of anemia?
most occur only if anemia is severe
Weakness, fatigue, seeing spots, drowsiness, syncope, angina, SOB, DOE. May also see vertigo, HA, tinnitus, pica, restless leg syndrome, amenorrhea or menorrhagia, loss of libido, and GI complaints.
What are important signs in PE to assess for anemia?
Blood pressure - supine, seated and standing (orthostatic)
Inspect conjunctiva, lines of palms, mucus membranes, skin color - pallor
Inspect nails for blueness, ridges, spooning, poor nutrition
Cardiovascular exam - increased heart rate, murmurs,
Splenomegaly
peripheral neuropathy
abdominal distention
petechiae
What are some tests that could be done to assess anemia?
Stool occult blood test
CBC with peripheral smear to help differentiate deficient RBC production from excessive RBC destruction
Iron, ferritin, TIBC if CBC or sxs warrant
TSH, free T4 (fatigue, menstrual complaints)
Serum bilirubin, LDH (elevated in hemolysis); if anemia is present
What is microcytic anemia? Some causes?
MCV <80 fL
Altered heme or globin synthesis from:
Iron deficiency, thalassemia, and Hb-synthesis defects, copper deficiency, zinc poisoning, lead poisoning, alcohol.
MB seen in anemia of chronic disease
What is macrocytic anemia? Causes?
MCV > 95 fL
Impaired DNA synthesis from:
B12, folate deficiencies, chemotherapeutic agents, alcoholism, HIV anti-retroviral agents, myelodysplastic disorders
What could cause normocytic anemia?
deficient EPO, hemorrhage
What do elevated reticulocytes indicate? What about decreased reticulocytes?
elevated = excessive RBC destruction decreased = low RBC production
Why would you see RBC fragments, ovalocytes, or schistocytes in smear?
RBC injury
What is meant by anisocytosis? Poikilocytosis?
Anisocytosis: RBCs of excessive variation in size are present
Poikilocytosis: RBCs of excessive variation in shape are present
What would be some indications for ordering bone marrow aspiration and biopsy?
Unexplained anemias Other cytopenias Unexplained leukocytosis Thrombocytosis Suspected leukemia, multiple myeloma, or myelophthisis
What lab result would indicate deficient erythropoesis? What are examples of anemias caused by deficient erythropoesis?
Seen by decreased reticulocytes (Reticulocytopenia)
Microcytic - iron deficiency anemias - iron-transport deficiency anemias - iron-utilization anemias - thalassemias Normocytic - bone marrow failure Macrocytic - B12, folate deficiencies
What is the most common anemia?
Iron deficient anemia
What are some symptoms of severe iron deficient anemia?
pica, glossitis, cheilosis, concave nails, increased heart rate, dyspnea, restless leg syndrome, glossal pain, reduced salivary flow leading to dry mouth, atrophy of tongue papillae, cheilosis, and occasionally, alopecia
Where is the GI is iron absorbed?
What percentage of iron is absorbed?
What is the daily requirement of iron?
How is non-heme iron absorbed?
Absorbed in stomach, duodenum and upper jejunum
about 1mg of every 15mg is absorbed
daily requirement - 25 mg/day
Absorbed best as heme iron (meat products)
Non-heme iron must be reduced and unbound from other food molecules (gastric secretions)
What helps iron absorption? What hinders iron absorption?
Ascorbic acid increases non-heme iron absorption
Reduced absorption by antacids, plant phytates (wheat, cereals), tannins (black tea), lead and malabsorption disorders such as achlohydria, atrophic gastritis, Helicobacter pylori gastritis, SIBO, gastric bypass, and celiac disease
How is iron stored in the body?
Ferritin – liver, bone marrow, spleen, RBCs, and serum
Hemosiderin – Liver, marrow
What are the causes of iron deficient anemia in men? in women? and in children?
MEN - chronic bleed (colon cancer, colitis, PUD, ASA use)
WOMEN - menstruation, repeated pregnancy
CHILDREN - growth spurts
Also due to chronic vascular hemolysis, post gastrectomy, malabsorption, under nutrition
What are some labs that would help diagnose iron deficient anemia?
- Stool Occult blood (Men, post-menopausal women, women with normal menses)
- Iron absorption test (fasting serum iron level is compared to a second serum iron level obtained one to four hours following oral ingestion of one 325 mg tablet of iron sulfate - Should increase at least 100 microg/dL if absorption is normal
- CBC with peripheral smear - LOW Hb, Hct, RBC, MCV, and HIGH RDW
- serum iron - LOW
- iron-binding capacity - HIGH
- serum ferritin - LOW
What is sideroblastic anemia?
- Inadequate or abnormal utilization of marrow iron, in spite of adequate stores
- Usu part of myelodysplastic syndrome, hereditary or secondary to drugs or other toxins. Reversibly if dt alcoholism, copper deficiency (zinc excess), drugs or hypothermia
- Also may occur in hemoglobinopathies (thalassemia)
How is sideroblastic anemia diagnosed (lab results)?
- CBC - microcytic, high RDW
- serum iron - HIGH
- transferrin - HIGH
- ferritin - HIGH
- peripheral smear - anisocytosis,
- BM biopsy - erythroid hyperplasia
*Check serum lead concentration if cause is unknown
What are some causes of anemia of chronic disease?
infectious inflammatory neoplastic disease severe trauma heart failure diabetes mellitus anemia of the elderly acute/chronic immune activation
What are labs done to diagnose anemia of chronic disease?
CBC - (Hb usually 10-11, normo/microcytic, normo/hypochromic, RDW normal early)
peripheral smear
Iron values are normal unless underlying deficiency
ESR and CRP if underlying cause is unknown
EPO maybe depressed
What is hypoproliferative anemia?
Low marrow activity due to lack of EPO or inability of marrow to respond to it
Associated with renal disease
Also associated with hypo metabolic/endocrine deficiency states: hypothyroidism, hyperthyroidism, panhypopituitarism, and primary or secondary hyperparathyroidism
What are some causes of aplastic anemia?
genetic or acquired
- Chemical exposure: drugs, pesticides, industrial chemicals, benzenes, anti-cancer agents (unknown mechanisms)
- Infections such as Parvo-B19, HIV, hepatitis, EBV
- Genetic inability to clear toxicity via glutathione S-transferase
- Fanconi’s anemia – rare type of inherited aplastic anemia
- Pure red cell aplasia due to infections, thymomas, immune system injury, fertilizer exposure, B2 deficiency, CLL
What would be some SSxs of aplastic anemia?
- Anemia: pallor, tachycardia, fatigue, dizziness
- Thrombocytopenia: petechiae, ecchymosis, bleeding from gums, ocular fundi, other tissues
- Agranulocytosis: life-threatening infections
- Suspect in (particularly young) pts with pancytopenia (WBCs <50,000/µL)