Hematologic and oncologic disorders Flashcards
Normal lab values for RBCs
RBCs: 4-6
MCV: 80-100
-Microcytic <80
-Normocytic 80-100
-Macrocytic >80
MCHC: 32%-36%
MCH: 26-34
Reticulocyte count
Immature red blood cells
Normal: 0.5-2.5
High: Erythropoeitc response to anemia and probable blood loss of hemolysis.
Low: Anemia of marrow failure, most common cause of anemia.
Mean Corpuscular Volume (MCV)
Espression of the average volume and size of individual erythrocytes.
Normal: 80-100
Total iron binding capacity (TIBC)
Normal 250-450
>450 indicates low levels of iron in the blood.
<250 indicates high levels of iron in the blood.
Mean corpuscular hemoglobin conentration (MCHC)
Normal: 32%-36%
-Expression of the average hgb concentration or proportion of each RBC occupied by hgb as a percentage.
-More accurate measure than MCH
-How red the blood cell is.
-Low: less hgb=less red
-High: high hgb=more red
Microcytic, hypochromic anemias
Iron deficiency anemia & Thalassemia
Iron deficiency anemia
Microcytic, hypochromic anemia due to overall deficiency of iron.
Most common cause of anemia (excpet elderly pts which would be anemia of chronic disease)
Caused by: blood loss, inadequate iron intake, impaired absorption of iron.
**S/S: **Usually slow in onset and few symtpoms are seen with hct >30, but as hct falls will see pica, dyspnea, headache, palpitations, weakness, tachycardia, postural hypotension, pallor.
Labs/diagnostics: Low MCV, low MCHC, low ferritin, low serum iron, low hgb/hct, low RBCs, high TIBC, high RDW
Management: Oral ferrous sulfate (300-325mg) 1-2 hours after meals (food decreased iron absorption by 50%).
-Iron shouldn’t be taken with antacids as they decreased absorption
-Iron taken with Vitamin C increases absorption
Thalassemia
Genetically inherited disorders resulting in abnormal hgb production and microcytic, hypochromic anemia.
Found mainly in mediterranean, african, middle eastern, indian and asian populations. Asians with anemia, think thalassemia
**S/S: **general physical findings are unremarkable unless severe thalassemia.
-Beta thalassemia is the most familiar type of thalassemia (reduced or absent production of beta globin chains),
Two forms of beta thalassemia: Minor and major
-Thalassemia minor: Most common. Heterozygous (underproduced beta chains) for beta thalassemia. Minor anemia.
-Thalassemia major: Homozygous (zero beta chains) for beta thalassemia. More severe anemia.
**Labs/diagnostics: **low hgb, low MCV, low MCHC, normal TIBC, normal ferritin.
Management: No treatment for mild to moderate forms. RBC transfusion/splenectomy for more severe forms.
-Iron is contraindicated as iron overload can result.
Macrocytic, normochomic anemia
Folic acid deficiency, pernicious anemia, B12 deficiency
Folic acid deficiency
A macrocytic, normochromic anemia due to folic acid deficiency (<2). Inadequate intake/malabsorption of folic acid.
S/S: fatigue, dyspnea on exertion, pallor, HA, tachycardia, anorexia, glossitis. No neurological signs, which diffierentiates this from B12 deficiency
Lab/diagnostics: Hgb/hct/RBC low, serum folate low, MCV elevated, MCHC normal.
Management: Folate 1mg daily (always give B12 due to potential neurological symptoms)
Could be medication induced by methotrexate, alcohol, phenytoin, oral contraceptives, isoniazid
Pernicious anemia
A macrocytic, normochromic anemia due to deficiency of intrinsic factor(produced by parietal cells in stomach), which results in malabsorption of B12. Autoimmune inflammation in stomach that affects the inability to absorb B12.
**S/S: **Weakness, glossitis, palpitation, dizziness, anorexia, POSITIVE NEURO FINDINGS: paresthesia, loss of vibratory sense, loss of fine motor control, positive romberg and babinski signs.
Lab/diagnostics: Low hgb/hct/RBCs, MCV increased, MCHC normal, low serum B12 (<200), Anti IF and antiparietal cell antibody test is used to affirm a defficiency.
Management: B12 100mcg IM daily x1 week. Maintenance therapy requires continuous lifelong monthly administration. (Watch for hypokalemia)
Anemia of chronic disease
Chronic normocytic, normochromic anemia associated with chronic inflammation, infection, renal failure and malignancy. Most common in elderly. 2nd most common cause of anemia.
**S/S: **Fatigue, weakness, dyspnea on exertion, anorexia.
Lab/diagnostics: Low hgb and hct, low serum iron and TIBC, MCV and MCHC normal, high ferritin.
Management: Treat associated disease and provide nutritional support.
Erythropoetin for pts with chronic diseases such as kidney failure or RA.
Sickle cell anemia
Chronic hemolytic anemia that is genetically transmitted. Typically african americans.
A crisis is periodic exacerbations of vessel obstructions. Cellular hypoxia results in acidosis and tissue ischemia. Pain occurs from tissue ischemia and blood hyperviscocity. Factors which precipitate sickling include hypoxia, infections, high altitudes, dehydration, physical or emotional stress, surgery, blood loss and acidosis.
S/S: Signs of disease develop in infancy or childhood. Deleyed growth development, increased susceptibility to infections. In crisis pts experience: sudden onset of severe pain in extremities/back/chest/abdomen, aching joints, weakness, dyspnea.
Lab/diagnostics: low hgb, peripheral smear shows classic distorted sickle shaped RBCs.
**Management: **Treat both acute and chronic complications of the disease. For acute exacerbation give fluids for dehydration, pain meds, and oxygen for hypoxia.
Von Willebrand Disease
A genetic disorder that results in the reduced ability to create blood clots. Caused by mutation of deficiency in von Willebrand factor and clotting factor 8.
S/S: Frequent, prolonged or severe episodes of bleeding. Easy bruising.
Management: Desmopressin (DDAVP).
Idiopathic thrombocytopenia purpura (ITP)
Thrombocytopenia resulting from autoimmune destruction of platelets with or without suppression of thrombopoiesis.
Normal platelets 150-400
S/S: in adults, ITP is usually chronic and causes mild to severe thrombocytopenia that my be asymptomatic.
Thrombocytopenia may be incuded by: Heparin, sulfonamides, thiazides, quinine, zosyn, gold.
Lab/diagnostics: Bone marrow analysis, low platelet count with other causes of thrombocytopenia ruled out.There may be a history of easy brusing and bleeding (gums and kidneys bleed first).
Management: May not be needed until platelets are <20,000.
-IV steroids and IV gammaglobulin increase platelet count. Platelet transfuion may be beneficial.
IV gammaglobulin is prefered over steroids in HIV-ITP
Splenectomy is highly effective