Exam 3 - Hem/Onc Flashcards
What is the definition of hematocrit?
Amount of space in the blood that is occupied by RBCs
What is the definition of MCV?
Average size of RBCs
What is the definition of MCH?
Average amount of hemoglobin in each RBC (color)
What does a reticulocyte count indicate?
Number of young RBCs → RBC production
- Higher reticulocyte count = more production
What does a red cell distribution width (RDW) indicate?
Measurement of variation in RBC size
- Higher RDW = more variation (young vs old RBC)
What is the definition of anemia? Is anemia a diagnosis?
Decreased RBC and hemoglobin or hematocrit
- NOT a diagnosis → s/s of an underlying disorder
- Identify source and treat it appropriately
Causes of anemia → RBC production disorders
- IDA
- Anemia of chronic disease (ACD)
- Vitamin B12 and folate deficiency
- Aplastic anemia
Causes of anemia → RBC destruction disorders
- Sickle cell anemia
- Hereditary spherocytosis and elliptocytosis
- G6PD deficiency
- Autoimmune hemolytic anemia
Causes of anemia → blood loss (acute or chronic)
Trauma, hemorrhage, menorrhagia, hematuria, GI bleeding
Normal RBC levels in men and women
Men: >13.6 g/dL
Women: >12 g/dL
Anemia clinical manifestations
- If healthy, few s/s until hemoglobin falls below 7.5 g/dL → Fatigue, malaise, HA, dyspnea, irritability, mild decrease in exercise tolerance
- Moderate to severe anemia: wide pulse pressure, midsystolic or pansystolic murmur, confusion, lethargy, brittle nails, glossitis, angular cheilitis, spoon shaped nails
- Pallor of mucous membranes, lips, conjunctivae, nail beds, palmar creases
- Forceful apical pulse, tachycardia with exertion, systolic murmur
Anemia diagnostics
- CBC w/ diff
- Reticulocyte count
- Peripheral blood smear
What diagnostic labs are most sensitive for anemia?
- Serum bilirubin
- Lactate dehydrogenase
What labs should be collected for suspected microcytic anemia or IDA?
Iron profile
What is the definition of microcytic anemia?
Small RBCs → less hemoglobin, less volume
- Due to iron deficiency (without iron RBCs cannot grow or be produced)
Microcytic anemia lab results
- Low MCH, low MCV
- Low/normal reticulocyte count (low RBC production)
- Increased RDW (newer cells are smaller than old cells)
- High TIBC (RBCs really want iron)
What is the definition of macrocytic anemia?
Large RBCs → more hemoglobin, more volume
- Due to folate or vitamin B12 deficiency (without either RBCs cannot divide/undergo mitotic division)
Macrocytic anemia lab results
- High MCH, high MCV
- Low/normal reticulocyte count (low RBC production)
- Increased RDW
- Normal TIBC (RBCs have enough iron)
Possible causes of normocytic anemias
- Congenital → sickle cell disease, G6PD deficiency
- Hemolysis
- Acute/large volume blood loss
- Anemia of chronic disease (ACD)
Types of microcytic anemia
- IDA
- Thalassemia
Types of macrocytic anemia
Megaloblastic (vitamin B12/folate deficiency)
IDA peripheral smear findings
- Hypochromia
- Microcytosis
- Mild anisocytosis
- Poikilocytosis
Are microcytic and macrocytic hypo proliferative or hyper proliferative?
Hypo proliferative = lack nutrient for proper RBC production
- Low reticulocyte count
Iron profile findings for IDA
- Low serum iron
- Low ferritin
- Low % transferrin saturation
- Elevated TIBC (looking for iron to bind to)
What is the most sensitive test to assess IDA?
Ferritin
- Levels decline when iron storage depletes
- Ferritin = storage of iron (body will use this when levels of iron are low)
Causes of IDA
- MCC: chronic blood loss (GI bleed, menorrhagia)
- Inadequate nutrition in children and pregnant women
- Malignancy
IDA treatment for adults
Iron supplementation (150-200 mg elemental iron daily)
Iron supplementation side effects
- N/D/C (prescribed with stool softeners)
- Heartburn
- Upper GI discomfort
- Black stools
How to best take iron for maximum absorption
Taken 30 minutes before meals with ascorbic acid (vitamin C)
- Decreased with ingestion of MV with calcium or diary products
When should the provider consider parenteral administration of iron supplementation?
- Referral to hematologist for IV administration
- Severe anemia
- Iron malabsorption problem
- Oral iron not tolerated
IDA treatment during pregnancy
Prenatal vitamins with iron
IDA treatment for full term healthy infants (breast-feeding considerations)
Babies have adequate iron stores for up to 4-6 months of life
- Exclusively breastfed babies over 4 months or lack iron fortified foods by 6 months need iron supplementation
What is the Mentzer index?
Used to differentiate between IDA and beta thalassemia minor
What is hemoglobin electrophoresis?
Measures different types of hemoglobin in the blood
- Screens for genetic conditions
- Can differentiate between IDA and thalassemia
What is thalassemia?
Autosomal recessive inheritance
- Causes microcytic and hypo chromic anemia similar to IDA
Thalassemia lab findings
- Low MCV and MCH
- High RBC (different from IDA)
Thalassemia pregnancy and newborn considerations
- Alpha thalassemia can be diagnosed during routine newborn screening
- Women of childbearing age should be referred to genetic counseling if considering conceiving
Thalassemia clinical manifestations
- Minor (mild) → no hematologic effects or mistaken for IDA
- Intermedia (moderate) → moderate microcytic and hypochromic anemia that is not transfusion dependent
- Major (severe) → developmental problems, decreased life expectancy, lifelong chronic RBC transfusions
- Short stature, abnormal facies (cranial marrow expansion)
- Diagnosed as early as 3 months of age: severe anemia, pallor, jaundice, enlarged spleen, liver, heart
Thalassemia management
- Regular blood transfusions to maintain adequate hemoglobin level to allow normal growth and development
- Iron chelation therapy to prevent complications of transfusion-dependent iron overload
Causes of vitamin B12 deficiency (macrocytic anemia)?
- Strict vegetarian
- Pernicious anemia → loss of intrinsic factor, unable to absorb B12 from diet
- Chronic use of PPIs
- Other malabsorption problem
Vitamin B12 deficiency symptoms
- Neurological deficits (if severe): decreased vibratory sensation, loss of proprioception, peripheral neuropathy, ataxia, spasticity, hyperactive reflexes, positive Romberg sign
- Beefy red tongue
Vitamin B12 deficiency lab findings
- Low hemoglobin
- Elevated MCV
- Elevated RDW
- Low reticulocyte count
What is a Schillings test?
Previous way of diagnosing pernicious anemia
- Now use anti-IF or anti-parietal cell antibodies
Causes of folate deficiency
- Dietary
- Alcoholism
- Malabsorption
- Increased requirements during pregnancy
Folate deficiency lab findings
- Low hemoglobin
- Elevated MCV
- Elevated RDW
- Low reticulocyte count
Folate deficiency pregnancy considerations
Deficiency during pregnancy can lead to neural tube defects in the fetus
Anemia of chronic disease (ACD) definition
Mild to moderate anemia that results from inflammatory disorders, infection, or malignancy
Causes of anemic of chronic disease (ACD)
- Malignancy
- Chronic infection
- Autoimmune conditions (RA, SLE, IBD)
- Chronic kidney disease
Anemia of chronic disease (ACD) clinical manifestations
- Mild and asymptomatic
- Have symptoms associated with underlying diseases (gradual onset)
- Fatigue, pallor, tachycardia, dyspnea with exertion
Anemia of chronic disease (ACD) treatment
- Manage underlying condition
- Recombinant human erythropoietin or darbepoetin alfa → EPO triggers production of RBC
- Blood transfusions
Sickle cell disease (SCD) vs sickle cell trait
Sickle cell trait: only carry one copy of the altered hemoglobin gene (do not have clinical symptoms)
Sickle cell disease: carry two copies of altered hemoglobin gene
- Autosomal recessive inheritance
SCD (hemolytic anemia)- moderate to severe clinical manifestations
- Jaundice
- Systolic flow murmur (grade 1 or 2)
- Scleral icterus
- Cardiomegaly
At what age do symptoms of SCD emerge?
Around 6 months of age
Multisystem symptoms of SCD
- Fatigue
- Pain
- Bacterial infections (functional asplenia)
SCD lab findings
- Low HCT and Hgb
- High reticulocyte count
- Elevated LDH and bilirubin
Gold standard method of diagnosis for SCD
Hemoglobin electrophoresis
Triggers that lead to SCD vaso-occlusive crisis
- Physical stresses → infection, change of weather (exposure to cold), dehydration, fatigue, overexertion
- Emotional stress
Nonpharmacologic management of SCD
- Oral analgesics (NSAIDs)
- Hydration
- Rest, heat, gentle massage
- Illness prevention (immunizations), monitor growth and development
Pharmacologic management of SCD
- ER admission (work with pediatric hematologist)
- IV narcotic analgesics and fluids
- Antibiotic prophylaxis for infants and young children
SCD complications
- Chronic pain → confused for narcotic dependence
- Infants and toddlers → dactylitis
- Children → acute splenic sequestration (higher risk of infection, life threatening)
- Adults → pulmonary HTN, renal failure, priapism, skin ulcerations, stroke
What is aplastic anemia?
Life threatening condition resulting from bone marrow stem cell failure → pancytopenia
- Sudden onset
Causes of aplastic anemia
Secondary to infection, exposure to toxins or medications, immune mediated
Aplastic anemia - clinical presentation and physical examination
Clinical presentation → abnormal bleeding, infection, anemia
Physical exam → petechiae, ecchymosis, purpura, pallor of skin and mucous membranes, lymphadenopathy (late stages)
True/false: The early stages of aplastic anemia may show no significant changes on physical exam
True
Aplastic anemia CBC findings
- Pancytopenia with normocytic and normochromic RBCs
- Normal reticulocyte count
Gold standard diagnosis of aplastic anemia
Bone marrow biopsy
Aplastic anemia management
- Referral to hematologist
- Non severe cases can be observed with supportive care
- Avoid infections → hand hygiene, avoid ill contacts, immunizations
What is the definitive treatment of aplastic anemia?
- Immunosuppressive therapy
- Bone marrow transplant
What is von willebrand disease (vWD)?
Deficiency or abnormality of vWF (coagulopathy) → most common congenital bleeding disorder
- Autosomal dominant inheritance
vWD clinical manifestations
- Epistaxis
- Menorrhagia
- Excessive bruising
- Prolonged bleeding with cuts or dental extractions and in intraoperative or immediate postoperative period
vWD management
- Hematology consultation → interdisciplinary
- Treatment for bleeding episodes
- Prophylaxis for invasive procedures
- DDAVP or plasma-derived factor VIII concentrate
What is hemophilia?
X-linked recessive bleeding disorder → low factor VIII or IX → defective fibrin clot formation
Hemophilia diagnostic lab findings
- Normal PT, thrombin time, PFA-100
- Prolonged aPTT
- Diagnosis requires finding of low level of factor VIII (A) or factor IX (B)
Hemophilia management (mild and severe cases)
- Mild → coagulation factor replacement (DDAVP)
- Moderate/severe → replacement of coagulation factor via infusions
Hemophilia patient education
- Avoid high contact sports, aspirin and NSAIDs
- Evaluate coagulation status before dental procedures or surgeries
- Genetic counseling for family planning
Hemophilia complications
- Bleeding into joints can lead to joint swelling, joint immobility, and limb contractures
- Anemia
- Bleeding into various organs
What is idiopathic thrombocytopenia purpura?
Most common thrombocytopenic purpura in childhood (ages 1-4 years)
- Believed to be autoimmune response in which circulating platelets are destroyed
- Usually preceded by a viral illness
Acute vs chronic ITP
Acute: most cases resolve within 6 months
Chronic: >12 months
ITP clinical manifestations
Symptoms do not present until platelet count is <20,000
- Acute onset petechiae, purpura, bleeding/bruising (usually over legs)
- Recent viral illness 1-4 weeks ago
- Nosebleeds
- Hemorrhage of gums and lips
Lab findings in ITP
- Low platelet count
- Normal PT and aPTT
- Normal WBC and RBC count
- Megathrombocytes on peripheral smear
- Severe thrombocytopenia
- Decreased Hgb with normal MVC
ITP management - mild cases
If platelet count >20,000 and no bleeding observed → avoid contact sports, aspirin and NSAIDs, other agents that could interfere with platelet function
ITP management - severe cases (platelets <20,000)
- Short course corticosteroid therapy
- IVIG - for active severe bleeding and those with contraindications for steroid therapy
- Thrombopoiesis stimulants → romiplostim, eltrombopag
What is the function of neutrophils?
Bacterial or fungal infections (most common)
- Neutrophilia (elevated) → “left shift”
What is the function of eosinophils?
Parasitic infections and allergic reactions (inflammatory)
What is the function of basophils?
Allergic and antigen response (release histamines)
- Rare, but should be concerned about malignancy
What is the function of lymphocytes?
Include B cells, helper T cells, cytotoxic T cells
- Operate in lymphatic system (viral illnesses)
What is the function of monocytes?
Phagocytosis of pathogens
- Presentation of antigens to T cells
- Eventually become macrophages
What is leukemia?
Hematologic malignant neoplasms that affect the bone marrow and lymphatic tissue
What is acute leukemia?
Abnormal production of immature WBC (blasts) with rapid disease progression → AML, ALL
What is chronic leukemia?
Overabundance of mature appearing but ineffective WBCs with slow disease progress → CML, CLL
Leukemia red flags
- WBC 500-30,000 cells/mm3
- Leukopenia with >20% blasts
- Enlarged, non tender lymph nodes present for >1 month
Diagnostic tests for leukemia
- CBC w/ differential
- Bone marrow biopsy
- Blood smear → will see increased blasts
- CT scan or PET scans
Leukemia management
- Hematology/oncology referral
- Chemotherapy, immunotherapy, targeted therapy
- Stem cell transplantation for high risk disease
What is lymphoma?
Clonal disorder that arises from lymphocytes (B or T cells) → Hodgkins or Non Hodgkin’s lymphoma
Lymphoma clinical manifestations
- Lymphadenopathy → lymph nodes persisting for more than 4 weeks or larger than normal (up to 1.5 cm)
- Fever higher than 38 degrees C
- B symptoms: drenching night sweats, unintentional weight loss or more than 10% body weight, fatigue
- Absence of palpable liver and spleen
Hodgkin vs Non Hodgkins lymphoma clinical presentation
Hodgkins → Reed-Steinberg cells, adenopathy in neck (usually involves mediastinum)
Non Hodgkins → cytopenia, can have rapid or insidious onset of symptoms
