Anaemia

Question 1

what is anaemia?

Answer 1

Reduced levels of haemoglobin (Hb) concentration in the blood. It’s a symptom (not disease) of conditions including extensive blood loss, excess blood cell destruction & decreased blood cell formation

Question 2

how else can anaemia occur other than reduced levels of haemoglobin?

Answer 2

anemia can also occur if the haemoglobin is of poor quality or if there are structural abnormalities in the red blood cells (RBCs), as seen in conditions like sickle cell disease or thalassemia.

In these cases, while the total amount of hemoglobin may be within the normal range, the hemoglobin may not function properly or may not carry oxygen effectively. This can still lead to symptoms and complications associated with anemia, even if the hemoglobin concentration is not below the WHO-defined thresholds.

Question 3

what are the values for anaemia according to WHO?

Answer 3

Male: hb < 130g/l

Female: hb < 120 g/l

Pregnant: hb < 110 g/l

Question 4

acronym for symptoms of anaemia

Answer 4

LIP SHAPED (leg cramps, insomnia, pale skin, shortness of breath, headaches, apathy/lethargy, palpitations, exhaustion, dizziness/faint)

Question 5

what are the various mechanisms that can lead to anaemia?

Answer 5

Low rate of production of RBCs:

Low levels of erythropoietin (Epo) due to kidney disease, which affects the stimulation of red blood cell production.

Hormone deficiency diseases that impact the production of red blood cells.

RBCs produced are of poor quality:

Vitamin B12 deficiency anemia and folate deficiency anemia, which affect DNA synthesis and ultimately RBC production.

Inherited conditions like sickle cell disease and thalassemias, which result in abnormal hemoglobin and RBC structure.

RBCs do not survive 120 days:

Chronic hemorrhaging (bleeding), which can lead to a constant loss of red blood cells, ultimately causing anemia

Question 6

what are the potential causes of anaemia in infants and children categorised by the underlying mechanisms?

Answer 6

Impaired Red Cell Production:

Red cell aplasia: Parvovirus B19 infection
Diamond-Blackfan anemia (congenital red cell aplasia)
Transient erythroblastopenia of childhood
Rare conditions like Fanconi anemia, aplastic anemia, and leukemia

Ineffective Erythropoiesis:

Iron deficiency anemia
Folic acid deficiency anemia
Chronic inflammation (e.g., juvenile idiopathic arthritis)
Chronic renal failure
Rare conditions like myelodysplasia and lead poisoning

Increased Red Cell Destruction (Hemolysis):

Red cell membrane disorders: Hereditary spherocytosis

Red cell enzyme disorders: Glucose-6-phosphate dehydrogenase (G6PD) deficiency

Hemoglobinopathies: Thalassemia, Sickle cell disease

Immune-Mediated Hemolysis:

Hemolytic disease of the newborn (HDN)
Autoimmune hemolytic anemia

Blood Loss:

Fetomaternal bleeding
Chronic gastrointestinal blood loss (e.g., Meckel diverticulum)
Inherited bleeding disorders: Von Willebrand disease

Question 7

what are the two main categories of anaemia based on the underlying factors?

Answer 7

1) Absolute Anemia (Low Red Cell Volume):

Absolute anemia is characterized by a decrease in the actual number or volume of red blood cells (RBCs) in the bloodstream.

It can result from various mechanisms, including:

Low Red Cell Production: When the bone marrow fails to produce an adequate number of red blood cells. This can occur due to factors such as nutritional deficiencies (e.g., iron, vitamin B12, folate), bone marrow disorders, or chronic diseases that affect erythropoiesis.

High Red Cell Destruction (Hemolysis): When RBCs are destroyed at a rate that exceeds their production. Hemolysis can be caused by various factors, including inherited conditions (e.g., hereditary spherocytosis), acquired conditions (e.g., autoimmune hemolytic anemia), or infections.

Blood Loss: When there is significant bleeding, whether acute (e.g., trauma) or chronic (e.g., gastrointestinal bleeding), leading to a loss of RBCs.

Blood Redistribution: In some cases, anemia can result from the redistribution of blood within the body, where RBCs are concentrated in one area (e.g., spleen) rather than circulating in the bloodstream.

2) Relative Anemia (High Plasma Volume):

Relative anemia occurs when there is a dilutional effect on the concentration of red blood cells in the bloodstream due to an increase in plasma volume (the liquid portion of blood).

This type of anemia does not involve a decrease in the actual number or volume of RBCs. Instead, it gives the appearance of anemia because the ratio of RBCs to plasma is lower than normal.

Common causes of relative anemia include conditions that lead to an expansion of plasma volume, such as excessive fluid intake, certain kidney diseases, or certain medications.

Question 8

what are the different causes of anaemia?

Answer 8

Hypoproliferative Anemia:

Hypoproliferative anemia is characterized by a reduced production of red blood cells (RBCs). It can result from various causes, including:

Marrow Damage: Conditions that damage the bone marrow, such as chemotherapy, radiation therapy, or certain medications.

Iron Deficiency: Inadequate iron levels can impair RBC production.

Low Stimulation: Reduced stimulation of RBC production due to factors like chronic renal disease, inflammation, or metabolic disorders.

Maturation Disorders:

Maturation disorders refer to abnormalities in the maturation of red blood cells. These can be categorized based on cytoplasmic or nuclear defects:

Cytoplasmic Defects: Conditions like thalassemia, iron deficiency anemia, and sideroblastic anemia can lead to abnormalities in the cytoplasm of RBCs.

Nuclear Maturation Defect: Conditions such as folate deficiency, vitamin B12 deficiency, and refractory anemia can affect the nuclear maturation of RBCs.

Hemorrhage/Hemolysis:

Hemorrhage and hemolysis both result in a loss of red blood cells:

Blood Loss: Anemia due to blood loss can occur from various causes, including gastrointestinal bleeding, trauma, or surgery.

Intravascular Hemolysis: Conditions that cause the destruction of RBCs within the bloodstream.

Autoimmune Disease: Autoimmune hemolytic anemia involves the immune system mistakenly attacking and destroying RBCs.

Hemoglobinopathy: Conditions like sickle cell disease or thalassemia involve structural abnormalities in hemoglobin, which can lead to RBC destruction.

Metabolic/Membrane Defects: Certain genetic conditions can affect RBC metabolism or membrane integrity, leading to hemolysis.

Question 9

what are the classification of anaemias based on morphological features?

Answer 9

Microcytic Anemias: These anemias are characterized by smaller-than-normal RBCs. Causes include:

Iron Deficiency Anemia: The most common cause of microcytic anemia, characterized by insufficient iron stores.

Thalassemia: A group of inherited disorders affecting hemoglobin production.

Sideroblastic Anemia: A condition in which the body has difficulty using iron to make hemoglobin.

Anemia of Chronic Diseases (Severe Cases): Chronic illnesses like inflammatory conditions can lead to microcytic anemia when severe.

Normocytic Anemias: In these anemias, RBC size is within the normal range, but the overall number of RBCs or hemoglobin is decreased. Causes include:

Anemia of Chronic Diseases (Most Cases): Chronic inflammatory conditions can result in normocytic anemia.

Iron Deficiency (Early): In the early stages of iron deficiency, before microcytosis develops.

Anemia of Renal Disease: Kidney dysfunction affects erythropoietin production.

Combined Nutritional Deficiencies: Simultaneous deficiencies in iron and other nutrients like folate or cobalamin (vitamin B12).

Marrow Failure: Conditions affecting the bone marrow’s ability to produce RBCs.

Hypothyroidism: An underactive thyroid can lead to normocytic anemia.

Macrocytic Anemias: These anemias are characterized by larger-than-normal RBCs. Causes include:

Megaloblastic Anemia: Typically caused by deficiencies in folate or cobalamin (vitamin B12), resulting in abnormal RBC maturation.

Hemolytic Anemia (Reticulocytosis): Increased production of immature RBCs (reticulocytes) in response to hemolysis.

Liver Disease: Liver dysfunction can affect RBC size.

Hypothyroidism: An underactive thyroid can lead to macrocytic anemia.

Myelodysplasia: A group of disorders characterized by dysfunctional bone marrow.

Question 10

what are the different terms related to chromic characteristics of red blood cells?

Answer 10

Hyperchromic: Hyperchromic means that the red blood cells appear more intensely colored or “hyper” in terms of hemoglobin content. This term is less commonly used in clinical practice, but it can be associated with certain conditions where there is an increased concentration of hemoglobin in each red blood cell. For example, congenital spherocytic anemia can lead to hyperchromic red blood cells due to their characteristic shape and decreased cell volume.

Normochromic: Normochromic means that the red blood cells have a normal or typical hemoglobin content. In other words, they have the usual amount of hemoglobin for their size and appearance. Normochromic anemia indicates that the red blood cells are not abnormally pale (hypochromic) or intensely colored (hyperchromic).

Hypochromic: Hypochromic means that the red blood cells appear paler than normal due to a reduced hemoglobin content. In hypochromic anemia, the cells contain less haemoglobin than they should, which can result from conditions such as iron deficiency anaemia, where there is insufficient iron available to produce normal haemoglobin.

Question 11

what are the key characteristics of iron deficiency anaemia?

Answer 11

Depletion of Iron Stores: Iron deficiency anemia typically develops after the body’s iron stores, which are primarily found in the liver, bone marrow, and other organs, have been depleted. This means that the body has used up its stored iron reserves.

Adequate Erythropoietin: Erythropoietin (Epo), a hormone produced by the kidneys, is responsible for stimulating the production of red blood cells in the bone marrow. In iron deficiency anemia, erythropoietin levels are generally normal or even elevated because the body recognizes the need for more red blood cells.

Insufficient Iron: The primary problem in iron deficiency anemia is a lack of available iron, which is required for the synthesis of hemoglobin. Without sufficient iron, the body cannot produce enough hemoglobin to form functional red blood cells.

Question 12

what are the common causes of iron deficiency anaemia?

Answer 12

Habitual Blood Loss: Chronic or recurrent blood loss can deplete iron stores over time. Common sources of blood loss include:

Long or heavy menstrual bleeding in women, which can be exacerbated by conditions like fibroids.

Gastrointestinal bleeding from various sources, including ulcers, gastrointestinal cancers, or inflammatory bowel diseases.

Dietary Factors: An inadequate or unhealthy diet can lead to iron deficiency if it does not provide sufficient iron intake to meet the body’s needs.

Increased Demand During Pregnancy or Childhood: Iron requirements are higher during periods of rapid growth, such as pregnancy and childhood. If dietary intake is insufficient to meet these increased demands, iron deficiency can occur.

Inability to Absorb Iron: Certain medical conditions can affect the body’s ability to absorb iron from the diet. Conditions like celiac disease or inflammatory bowel disease can interfere with iron absorption in the digestive tract.

Surgery: Surgical procedures that involve the removal of part of the gastrointestinal tract can affect iron absorption, leading to iron deficiency anemia.

Medications: Some medications, such as proton pump inhibitors (used to treat acid reflux) or nonsteroidal anti-inflammatory drugs (NSAIDs), can contribute to gastrointestinal bleeding or interfere with iron absorption.

Question 13

what are the signs of iron deficiency anaemia?

Answer 13

koilonychia, brittle nails, angular stomatitis, lethargy & fatigue, chest pain, pale skin, light headedness, tachycardia, headache, cold hands & feet, dyspnoea, glossitis/smooth tongue

Question 14

what are the unusual signs of iron deficiency anaemia?

Answer 14

eating talc, rock, metal, ice

Question 15

what are the symptoms/characteristics associated with anaemia?

Answer 15

Rectal lesions: Rectal lesions can be a rare but possible symptom of anemia. Anemia can lead to gastrointestinal issues, including bleeding in the digestive tract, which may present as rectal lesions or bloody stools.

Growth impairment: Anemia, especially in children, can affect growth and development. The reduced oxygen-carrying capacity of the blood can hinder normal growth.

Cognitive and behavioral impairment: Severe anemia can lead to reduced oxygen delivery to the brain, which may result in cognitive impairment, difficulty concentrating, and changes in behavior.

Heart failure: Severe anemia can put extra strain on the heart because it has to work harder to deliver oxygen to the body’s tissues. This increased workload can lead to heart failure in some cases.

Recurrent infections: Anemia can weaken the immune system, making individuals more susceptible to infections.

Restless legs: Restless legs syndrome (RLS) is a condition characterized by an uncontrollable urge to move the legs, often accompanied by uncomfortable sensations. Anemia can sometimes exacerbate RLS symptoms.

Hair loss: Anemia can lead to hair loss as a result of reduced blood flow to the hair follicles, which affects their growth and health.

Raised number of platelets: Anemia can sometimes lead to reactive thrombocytosis, where the body produces more platelets in response to the low oxygen-carrying capacity of the blood. This is the body’s attempt to compensate for the anemia.

Question 16

what factors/conditions are associated with anemia?

Answer 16

Pregnancy: Anemia during pregnancy is relatively common and is often due to an increased demand for iron to support the growing fetus and changes in blood volume.

Vegetarian or vegan diet: People following strict vegetarian or vegan diets may be at a higher risk of developing anemia because plant-based sources of iron are less easily absorbed by the body compared to heme iron found in animal products.

Menorrhagia: Excessive menstrual bleeding (menorrhagia) can lead to anemia, as it results in the loss of a significant amount of blood during each menstrual cycle.

Hookworm infestation: Hookworms are parasites that can cause intestinal bleeding, leading to iron deficiency anemia.

Haemodialysis: Individuals undergoing hemodialysis for kidney failure may develop anemia because the kidneys play a crucial role in the production of erythropoietin, a hormone that stimulates red blood cell production.

Coeliac disease: Coeliac disease is an autoimmune disorder that affects the small intestine’s ability to absorb nutrients, including iron. Chronic inflammation in the intestine can lead to anemia.

Gastrectomy: Surgical removal of all or part of the stomach (gastrectomy) can reduce the body’s ability to absorb certain nutrients, including vitamin B12 and iron, potentially leading to anemia.

NSAID use: Long-term or excessive use of nonsteroidal anti-inflammatory drugs (NSAIDs) can irritate the stomach lining and lead to gastrointestinal bleeding, which can result in anemia.

H. pylori infection: Helicobacter pylori (H. pylori) is a bacterium that can infect the stomach lining and cause gastritis or stomach ulcers. Chronic bleeding from these conditions can lead to anemia.

Question 17

how do you manage iron deficiency anaemia?

Answer 17

Packed Red Cell Transfusion: This is necessary in cases where patients with iron deficiency anemia have severe cardiovascular compromise. Transfusion helps quickly increase the oxygen-carrying capacity of the blood and can be a life-saving measure in critical situations.

Oral Iron Pills: Oral iron supplements are commonly used to treat iron deficiency anemia. The response to oral iron can be monitored through various parameters:

Reticulocyte Count: This count measures the number of young red blood cells in the blood and typically peaks within 1 to 2 weeks of starting iron supplementation.

Hemoglobin (Hb) Increase: Hemoglobin levels should start to rise by approximately 20 grams per liter (g/L) within 3 to 4 weeks of treatment.

Iron Stores: It may take up to 6 months of consistent oral iron supplementation for iron stores in the body to become fully replenished.

Dietary Adjustments: To improve the absorption of oral iron supplements, patients are often advised to:

Increase Ascorbic Acid (Vitamin C) Intake: Vitamin C can enhance the absorption of iron from the digestive tract.

Reduce Tea, Coffee, and Wine Consumption: These beverages can inhibit iron absorption, so limiting their intake can be helpful.

Dosage and Compliance: It’s important to ensure patient compliance with iron supplementation. Taking iron supplements twice a day (BD - bis in die) may be more effective than taking them thrice a day (TDS - ter die sumendus) for some individuals. Alternating days can also help improve iron absorption in some cases.

Intravenous (IV) Iron: In certain situations such as malignancy, trauma, and inflammatory bowel disease (IBD), oral iron may not be sufficient. In such cases, IV iron therapy may be recommended as it can provide a more rapid increase in iron levels.

Iron Supplementation During Pregnancy: Iron requirements can change during pregnancy. Typically, there is no need for additional iron supplementation in the first trimester. However, in the second and third trimesters, especially in the case of twin pregnancies, a higher iron dose may be required to meet increased demands.

Question 18

outline a diagnostic and treatment protocol for iron deficiency anaemia (IDA)

Answer 18

Emergency Cardiovascular Compromise: If a patient with suspected or confirmed iron deficiency anemia (IDA) is experiencing emergency cardiovascular compromise due to severe anemia, you would initiate the “Major Hemorrhage Protocol.” This protocol typically involves rapid assessment, stabilization, and the administration of blood products to address the critical situation.

No Emergency Cardiovascular Compromise:

If the patient has heart disease and their hemoglobin (Hb) level is less than 80 g/L, they may require intervention or treatment to manage the anemia in a controlled manner.

If the patient does not have heart disease but has an Hb level less than 70 g/L, they would also require treatment.

Treatment for Patients with Hb < 70 g/L (No Heart Disease): In this case, patients with an Hb level less than 70 g/L would typically receive 2 units of cross-matched blood. This blood transfusion helps to rapidly increase the oxygen-carrying capacity of the blood and improve the patient’s overall condition.

Question 19

what are the causes of microcytic anaemia?

Answer 19

Thalassemia: Thalassemia is a group of inherited blood disorders characterized by reduced or absent synthesis of globin chains, leading to abnormal hemoglobin production. This can result in microcytic and hypochromic RBCs.

Anemia of Chronic Disease (ACD): Some chronic inflammatory conditions, such as chronic infections, autoimmune disorders, and cancer, can lead to anemia. ACD is typically characterized by microcytic and normochromic RBCs.

Iron Deficiency Anemia (IDA): This is the most common cause of microcytic anemia. It occurs when the body doesn’t have enough iron to produce sufficient hemoglobin. Causes of iron deficiency anemia can include dietary deficiencies, poor iron absorption, chronic bleeding (e.g., from gastrointestinal ulcers, heavy menstrual bleeding), and certain medical conditions.

Lead Poisoning: Exposure to lead can interfere with heme synthesis, leading to microcytic anemia. This is more common in children who are exposed to lead-containing paints or environmental sources.

Sideroblastic Anemia: This rare genetic or acquired condition impairs the incorporation of iron into hemoglobin molecules, resulting in microcytic RBCs. It can be hereditary or caused by factors like certain medications or myelodysplastic syndromes.

Question 20

what is a useful mnemonic to remember the common causes of microcytic anemia?

Answer 20

TAILS (thalassemia, iron deficiency, chronic disease, lead poisoning, sideroblastic anaemia)

Question 21

what is the classification of anaemia based on red blood cell mean volume (MCV)?

Answer 21

Microcytic Anemia (MCV < 80 fl): In microcytic anemia, the average volume of red blood cells is smaller than normal. Common causes of microcytic anemia include iron deficiency anemia, thalassemia, sideroblastic anemia, and some other rare genetic and acquired conditions affecting hemoglobin synthesis or iron metabolism.

Macrocytic Anemia (MCV > 100 fl): Macrocytic anemia is characterized by larger-than-normal red blood cells. This type of anemia is often associated with vitamin B12 deficiency (pernicious anemia), folate deficiency, and certain medications or medical conditions affecting DNA synthesis and red blood cell maturation.

Normocytic Anemia (MCV 80-100 fl): In normocytic anemia, the average volume of red blood cells falls within the normal range. Causes of normocytic anemia can be diverse and include chronic diseases, hemolytic anemias, bone marrow disorders, and conditions affecting red blood cell production.

Question 22

what does normal haematopoiesis require?

Answer 22

Vitamin B12 (Cobalamin): Vitamin B12 is crucial for the production of healthy red blood cells. It is necessary for the maturation of red blood cell precursors.

Folate (Vitamin B9): Folate is another B-vitamin that plays a critical role in DNA synthesis and the maturation of red blood cells.

Amino Acids: Amino acids are the building blocks of proteins, including hemoglobin, which is essential for oxygen transport in red blood cells.

Energy: Adequate energy is required for the various metabolic processes involved in hematopoiesis.

Growth Factors: Various growth factors, such as erythropoietin (EPO), stimulate the production of red blood cells.

Hormones: Normal levels of hormones like growth hormone, thyroxine (T4), steroids, and androgens can influence hematopoiesis.

Copper: Copper is a trace mineral that plays a role in the formation of hemoglobin and is required for normal red blood cell production.

Vitamin C (Ascorbic Acid): Vitamin C enhances the absorption of non-heme iron from plant-based foods, which is important for hemoglobin synthesis.

Vitamin B6 (Pyridoxine): Vitamin B6 is involved in hemoglobin synthesis and the conversion of amino acids.

Vitamin B2 (Riboflavin): Riboflavin is essential for the metabolism of iron, which is a component of hemoglobin.

Question 22

what is erythrocytosis and polycythaemia?

Answer 22

Erythrocytosis: This term specifically refers to an excessive increase in the number of red blood cells (erythrocytes) in the blood. It is a condition where there is an elevated hematocrit (the proportion of blood volume occupied by red blood cells) or an elevated hemoglobin level. Erythrocytosis is primarily associated with an increase in red blood cells and their precursors.

Polycythemia: Polycythemia is a broader term that, as you mentioned, can refer to an excess of any blood cells, not just red blood cells. It can encompass conditions like erythrocytosis (excessive red blood cells), leukocytosis (excessive white blood cells), and thrombocytosis (excessive platelets). Polycythemia is a general term for an abnormal increase in the total number of blood cells.

To further add to the complexity, “Polycythemia Vera” is indeed a specific medical condition. Polycythemia Vera (PV) is a type of myeloproliferative disorder characterized by the overproduction of red blood cells, white blood cells, and platelets in the bone marrow. Despite the name, PV primarily involves erythrocytosis (excessive red blood cell production).