Anemia Flashcards
(30 cards)
What is the definition of anemia?
Low hemoglobin (Hb) concentration due either to a low red cell mass or increased plasma volume.
A low Hb is <13.5g/dL for men and <11.5g/dL for women.
What are the common symptoms of anemia?
- Fatigue
- Palpitations
- Angina (if CAD present)
- Dyspnea
- Headache
- Tinnitus
- Faintness
- Anorexia
Symptoms can vary depending on the etiology of anemia.
What are the general signs of anemia?
- Pallor
- Hyper dynamic circulation (compensatory)
- Tachycardia
- Ejection-systolic murmur over apex and aortic valve
- Cardiac enlargement and heart failure (high COP HF)
- Retinal hemorrhage (rarely)
Pallor is not a reliable sign of anemia.
How is anemia classified according to MCV?
- Microcytic
- Normocytic
- Macrocytic
Normal MCV is 76–96 fL per single RBC.
What are the causes of iron deficiency anemia (IDA)?
- Blood loss (most common)
- Decreased intake
- Malabsorption (e.g., coeliac disease)
- Increased demand (infancy, adolescence, pregnancy, lactation)
In the tropics, hookworm is a common cause of GI blood loss.
What are the symptoms specific to iron deficiency?
- Dysphagia
- Pica
- Loss of concentration
These symptoms can indicate the presence of iron deficiency.
What are the signs of iron deficiency anemia?
- Koilonychia (spoon-shaped nails)
- Atrophic glossitis (red glazed tongue)
- Angular cheilosis (ulceration at mouth sides)
- Esophageal webs (Plummer–Vinson syndrome)
Atrophic glossitis and angular cheilosis are also features of vitamin B12 and B2 deficiency.
What does a complete blood count (CBC) show in iron deficiency anemia?
- Decrease in MCV, MCH, and MCHC
- Microcytic, hypochromic anemia with anisocytosis and poikilocytosis
Blood film analysis is crucial for diagnosis.
What is the treatment plan for iron deficiency anemia?
- Oral iron (e.g., ferrous sulfate 200mg)
- Treat the cause and correct anemia
- Replenish iron stores
- Follow-up Hb should rise by 1g/dL/week
Continue treatment for at least 3 months after Hb normalizes.
What characterizes sideroblastic anemia?
A type of microcytic anemia not responding to iron, characterized by ineffective erythropoiesis and increased iron absorption.
Causes include congenital conditions and iatrogenic factors like chemotherapy.
What are the causes of macrocytic anemia?
- B12 deficiency
- Folate deficiency
- Alcohol excess
- Liver disease
- Hemolysis
- Cytotoxic drugs
Macrocytosis may not always indicate anemia.
What are the general causes of anemia?
- Reduced production of RBCs (hypoproliferative)
- Increased destruction/loss of RBCs (hyperproliferative)
These causes can often be distinguished by history and examination.
What is pernicious anemia?
A special kind of B12 deficiency anemia.
It often results from intrinsic factor deficiency, leading to malabsorption.
What are the causes of aplastic anemia?
- Bone marrow failure
- Exposure to toxins
- Certain infections
- Autoimmune diseases
Aplastic anemia leads to pancytopenia due to the failure of hematopoiesis.
True or False: Anemia can be diagnosed solely based on symptoms.
False
Anemia is primarily a laboratory diagnosis, requiring specific blood tests.
Fill in the blank: The mean corpuscular volume (MCV) is a measurement of the _______ of red blood cells.
[average size]
What can interfere with DNA synthesis?
Cytotoxic drugs
Cytotoxic drugs can interfere with DNA synthesis, affecting cell proliferation.
What characterizes non-megaloblastic macrocytic anemia?
Blood film shows no megaloblast
Non-megaloblastic anemia can be caused by factors like alcohol excess, liver disease, and hypothyroidism.
List some causes of folate deficiency.
- Poor diet (e.g., poverty, alcoholics, elderly)
- Malabsorption (e.g., coeliac disease, tropical sprue)
- Increased demand (e.g., pregnancy, hemolysis, malignancy)
- Alcohol
- Drugs (e.g., anti-epileptics, methotrexate, trimethoprim)
Folate is crucial for DNA synthesis and cell division.
What tests are included in the investigation of macrocytic anemia?
- Blood film
- Serum B12 and serum folate
- Red cell folate
- Liver function tests
- Thyroid function tests
- Bone marrow biopsy
Bone marrow biopsy is indicated if the cause is not revealed by other tests.
What are hypersegmented neutrophils and when are they typically seen?
Neutrophils with 6 or more nuclear lobes, typically seen in megaloblastic anemia due to vitamin B12 or folic acid deficiency
They may also be present in myelodysplastic syndromes and rare congenital conditions.
What is the primary source of folate in the diet?
Green vegetables, nuts, yeast, and liver
Folate is synthesized by gut bacteria and absorbed by the duodenum/proximal jejunum.
What are the treatment options for folate deficiency?
- Treat underlying cause (e.g., poor diet, malabsorption)
- Oral folic acid 5mg/day for 4 months
- Prophylactic doses in pregnancy (400mcg/day)
Folic acid should never be given without B12 as it may precipitate subacute combined degeneration of the cord in low B12 states.
What is the role of intrinsic factor (IF) in vitamin B12 absorption?
Intrinsic factor binds B12 in the stomach, enabling its absorption in the terminal ileum
Deficiency in intrinsic factor leads to pernicious anemia.
