Haemolytic Anaemia Types and Causes

Study Notes

Definition: Anaemia caused by the premature destruction of red blood cells
Types:
- Intrinsic: defects in red blood cell production (e.g. sickle cell anaemia, thalassemia)
- Extrinsic: destruction of normal red blood cells (e.g. autoimmune haemolytic anaemia, mechanical trauma)
Causes:
- Genetic defects (e.g. G6PD deficiency)
- Infections (e.g. malaria, babesiosis)
- Autoimmune disorders (e.g. lupus, rheumatoid arthritis)
- Medications (e.g. penicillin, quinine)
Symptoms:
- Fatigue
- Jaundice
- Dark urine
- Pale skin
Diagnosis:
- Blood tests (e.g. reticulocyte count, bilirubin level)
- Bone marrow examination
- Coombs test (for autoimmune haemolytic anaemia)

Definition: Anaemia caused by a lack of essential vitamins necessary for red blood cell production
Types:
- Vitamin B12 deficiency (pernicious anaemia)
- Folate deficiency
Causes:
- Poor diet
- Malabsorption (e.g. celiac disease, Crohn's disease)
- Increased demand (e.g. pregnancy, cancer)
Symptoms:
- Fatigue
- Shortness of breath
- Pale skin
- Headaches
Diagnosis:
- Blood tests (e.g. vitamin B12 level, folate level)
- Bone marrow examination
- Schilling test (for vitamin B12 deficiency)

Definition: Anaemia caused by a lack of iron necessary for haemoglobin production
Causes:
- Inadequate dietary iron intake
- Increased iron demand (e.g. pregnancy, menstrual bleeding)
- Chronic blood loss (e.g. ulcer, cancer)
- Malabsorption (e.g. celiac disease, gastric bypass surgery)
Symptoms:
- Fatigue
- Shortness of breath
- Pale skin
- Headaches
- Cold hands and feet
Diagnosis:
- Blood tests (e.g. haemoglobin level, iron level, ferritin level)
- Bone marrow examination

Premature destruction of red blood cells causes anaemia
Intrinsic defects: sickle cell anaemia, thalassemia
Extrinsic destruction: autoimmune haemolytic anaemia, mechanical trauma
Genetic defects: G6PD deficiency
Infections: malaria, babesiosis
Autoimmune disorders: lupus, rheumatoid arthritis
Medications: penicillin, quinine
Symptoms: fatigue, jaundice, dark urine, pale skin
Diagnosis: reticulocyte count, bilirubin level, bone marrow examination, Coombs test

Lack of essential vitamins necessary for red blood cell production causes anaemia
Vitamin B12 deficiency: pernicious anaemia
Folate deficiency
Causes: poor diet, malabsorption, increased demand
Symptoms: fatigue, shortness of breath, pale skin, headaches
Diagnosis: vitamin B12 level, folate level, bone marrow examination, Schilling test

Lack of iron necessary for haemoglobin production causes anaemia
Inadequate dietary iron intake
Increased iron demand: pregnancy, menstrual bleeding
Chronic blood loss: ulcer, cancer
Malabsorption: celiac disease, gastric bypass surgery
Symptoms: fatigue, shortness of breath, pale skin, headaches, cold hands and feet
Diagnosis: haemoglobin level, iron level, ferritin level, bone marrow examination