"Anaemia is defined as a decrease in the level of haemoglobin due to loss of a significant amount of red blood cells which decreases the oxygen- transporting capacity of blood."
It can result from either (mnemonic: AID)
- Acute/chronic blood loss as in hemorrhage/trauma cases
- Increased destruction of red cells due to hemolysis
- Decreased production (due to marrow hypoplasia or infection or certain nutritional deficiencies)
Anemia due to blood loss (acute/chronic) causes- (mnemonic- AGING)
- Acute Posthemorrhagic anaemia
- Gastro-Intestinal causes such as gastric ulcers, perforations, gastritis, hemorrhoids, cancer etc.
- NSAIDs such as aspirin and ibuprofen can cause ulcers and inflammation in the stomach lining.
- Gynaecological causes- Menstrual blood loss, childbirth, surgical compilcations, Nutritional deficiency during pregnancy.
Anemia due to increased destruction of red cells (hemolytic anemia)- (mnemonic- MAINS)
- Metabolic disorders such as G-6PD deficiency, Pyruvate kinase deficiency etc.
- Autoimmune diseases (auto-antibodies against red cell membrane)
- Inherited conditions such as Sickle cell anemia, thalassemia, etc.
- Neoplastic disorders and metastatic carcinoma
- Stress factors such as infections, drugs, smoking, alcohol etc.
Anemia due to decreased production of red blood cells- (mnemonic- SD is MAD)
- Stem cells abnormalities as in aplastic anemia and pure red cell aplasia
- Impaired DNA synthesis (megaloblastic anemia)
- Marrow aplasia or infiltration.
- Anemia of Chronic disease (Erythropoietin deficiency)
- Defect in hemoglobin synthesis (iron deficiency anemia)
☆ Note here that new red blood cells cannot be synthesised in case of Anemia due to decreased red cell production thus causing low reticulocyte counts. In case of anaemia due to blood loss and increased hemolysis, there is increased production of new red blood cells (reticulocytosis).
Clinical features (mnemonic- 3Ds to ANEMIA)
D- Diminution of vision
A- Altered taste sensations (tongue changes)
N- Numbness and Paraesthesia
E- Edema (pedal)
M- Mood fluctuations
I- Irregular periods/ Insomnia
A- Awareness of heartbeat (palpitations)
Diagnostic tests and investigations to detect anemia due to various causes:- (Note- not all tests are to be done in every case of anemia. The specific symtoms and signs are to be checked and specific tests done to rule out other causes of anemia)
- Iron indices (serum iron, ferritin levels, transferrin saturation, serum iron- binding capacity) in case of Iron deficiency anemia
- Plasma unconjugated bilirubin, haptoglobin levels in blood, lactate dehydrogenase levels in case of Hemolytic anemias
- serum folate and vitamin B12 concentrations in case of Megaloblastic anemia
- Electrophoresis to detect abnormal hemoglobin
- Red cell indices (MCH, MCHC, MCV, RDW)
- Hematocrit levels and hemoglobin concentrations
- Reticulocyte count
- Urinalysis and stool check.
- Bone marrow biopsy.
Hope that helped :)
- Jaskunwar Singh