Hematology #1 Flashcards
MCC of anemia worldwide
Iron deficiency anemia
What is the most common cause of iron deficiency anemia in the US
What is the most common cause of iron deficiency anemia in the world
- Chronic blood loss: menstruation, Colon cancer, Hookworms
- Diet (worldwide)
Risk factors for iron deficiency anemia
- Increased metabolic requirements: children, pregnant, lactating women
- Cow milk ingestion in young children: infants given cow’s milk < 1 year of age
Symptoms of iron deficiency anemia
- Fatigue, weakness, exercise intolerance, dyspnea
- Pasophagia (craving for ice)
- Pica (craving for non-food substances)
- Koilonychia (spooning of nails)
- Angular cheilitis (inflammation of both corners of mouth)
- Glossitis (smooth tongue)
What do iron studies in iron deficiency anemia show?
- Decreased ferritin
- Increased TIBC (transferrin)
- Decreased transferrin saturation
- Decreased serum iron
What gives a definitive diagnosis for iron deficiency anemia?
Bone marrow biopsy: absent iron stores
What is ferritin?
Ferritin stores iron in the blood
What is transferrin?
Transporters of iron in the blood (ferry)
-TIBC is the binding capacity of transferrin, so if they are increased, there is low iron in the blood
Treatment for iron deficiency anemia
-Iron replacement
What are some tips you should give patients when telling them how to take their iron replacement?
-Take iron with vitamin C (ascorbic acid), with water or orange juice and take on an empty stomach
What is the main cause of lead poisoning anemia in the US
-ingestion or inhalation of environmental lead (paint chips or lead dust)
Symptoms of lead poisoning anemia
- Neurologic symptoms: ataxia, fatigue, learning disabilities, wrist or foot drop
- Intermittent abdominal pain, vomiting, loss of appetite
Diagnostic for lead poisoning anemia
-Serum lead level > 10 mcg/dL on venous sampling most accurate
What does a peripheral smear for lead poisoning anemia?
Microcytic hypochromic anemia with basophilic stippling
-Ringed sideroblasts in the bone marrow
Treatment for lead poisoning anemia
- Removal of the source of lead (most important treatment)
- If 45-69 mcg/dL: Succimer (oral) or Calcium disodium (if oral no tolerated)
What is thalassemia?
Decreased production of globin chains
When should you consider thalassemia?
If microcytic anemia with normal serum Fe or no response to Fe treatment
Explain the absorption of B12
B12 is released by acidity of the stomach and combines with intrinsic factor where it is absorbed mainly in distal ileum
B12 deficiency causes ________. It is needed to convert ______ to methionine for DNA synthesis.
- Abnormal synthesis of DNA
- Homocysteine
Etiologies of B12 deficiency anemia
- Pernicious anemia (lack of intrinsic factor)
- Crohn Disease
- Chronic alcohol use
- H2 blockers and PPIs
- Metformin
- Vegan diet
What symptoms differ between B12 deficiency and folate deficiency anemia?
- In B12 deficiency, there are neurologic abnormalities.
- Symmetric paresthesias (MC initial symptom)
- Decreased DTRs
Labs for B12 deficiency
- Macrocytic anemia (Increased MCV)
- Increased homocysteine
- Increased methylmalonic acid (distinguishes B12 from folate)
For symptomatic B12 deficiency anemia or neuro findings, what should be given?
IM B12
-In adults, IM cyanocobalamin injection weekly until deficiency corrected, then monthly
MCC of folate deficiency anemia
-Inadequate intake: alcoholics, unbalanced diet
What do labs for folate deficiency show?
- Increased MCV
- Increased homocysteine
- Normal methylmalonic acid!!!!
MC initial presentation of sickle cell disease
Dactylitis (global swelling of finger or toe, sausage-like appearance)
What is seen on a peripheral smear for sickle cell disease?
- Sickled erthrocytes
- Decreased hemoglobin and hematocrit
- Howell-Jolly bodies
Although DNA analysis is always the definitive diagnostic for sickle cell disease, what is seen on hemoglobin electrophoresis?
Sickle cell disease: HbS, little to no HbA, increased HbF
Sickle cell trait: HbS, decreased HbA
What is the first step in management of pain crisis with sickle cell disease?
IV hydration and oxygen (reverses and prevents sickling)
What else is needed for RBC production and DNA synthesis in a sickle cell patient?
Folic acid supplementation
Hydroxyurea is given to sickle cell patients to reduce episodes. What is the MOA of Hydroxurea?
-Increases production of HbF (which does not sickle and has a higher affinity for oxygen), reduces RBC sickling
What type of osteomyelitis is usually associated with sickle cell disease?
Salmonella Osteomyeltitis
_______ is given as early as 2-3 months of age until at least 5 years old to prevent infectious complications
Prophylactic Penicillin
Thrombotic Thrombocytopenic Purpura (TTP) is due to
ADAMTS13 deficiency
What is the role of ADAMTS13?
Cleaves von Willebrand factor
Therefore, a deficiency in ADAMTS13 leads to
Large vWF multimers that cause small vessel thrombosis
Pentad of symptoms for TTP
- Thrombocytopenia: mucocutaneous bleeding
- Microangiopathic anemia: splenomegaly
- Neuro symptoms: headache, confusion, seizures
- Fever
- Kidney failure or uremia
Initial treatment of choice for TTP
-Plasmapheresis
Triad of symptoms with Hemolytic Uremic Syndrome (HUS)
- Thrombocytopenia
- Hemolytic Anemia
- Renal dysfunction (uremia)
Risk factors for HUS
-Predominantly seen in children with a recent history of gastroenteritis
What do labs show for HUS?
- Thrombocytopenia with normal coagulation studies
- Hemolysis: schistocytes (helmet cells)
- Increased BUN and Creatinine
Treatment for HUS
- Supportive therapy (fluid and electrolyte replacement, dialysis)
- Plasmapheresis
- NO ABX or ANTI-MOTILITY AGENTS
hemophilia A is a deficiency of
Factor VIII
Hemophilia A is an ______ disorder that occurs almost exclusively in _____. Because it is a deficiency of Factor VIII, it leads to failure of ______
X-linked recessive
Males
hematoma formation
Hemophilia B is an ______ disorder. It occurs almost exclusively in _____. It is a lack of factor ____ and therefore, can lead to a failure of hematoma formation.
X-linked recessive
Males
Factor IX (9)
Symptoms of Hemophilia A and Hemophilia B
- Hemarthrosis: delayed bleeding or swelling weight-bearing joints
- Excessive hemorrhage in response to trauma and surgery (tooth extraction, epistaxis)
What is aPTT?
Tells how long it takes for your blood to make a clot
-Tests response to anticoagulant therapies
What is PT?
Tells how long it takes for your blood to form a clot
Treatment for Hemophilia A
- Factor VIII infusion: first-line therapy
- Desmopressin (prior to procedures to prevent bleeding)
Treatment for Hemophilia B
- Factor IX infusion (first line therapy)
- Desmopressin is NOT useful in this type
