Anemia: Symptoms, Types, Signs and Causes

Anemia is a state in which the hemoglobin concentration falls below the accepted normal range depending on age and sex.

Classification Of Anemia Or Types Of Anemia

Classification of Anemia

1. Blood Loss:

• Post­hemorrhagic
• Chronic blood loss due to piles, hematemesis, menorrhagia
• Hookworm disease

2. Deficiency Ofhemopoietic Factors

• Iron defiiency
• Folate and vitamin B12 defiiency
• Protein defiiency, i.e., diarrhea, malabsorption

3. Bone Marrow Aplasia

• Aplastic anemia
• Pure red cell aplasia

Blood Diseases Symptoms

4. Anemia Due To Systemic Infections or Systemic Disorders:

• Anaemia due to chronic infection
• Anaemia due to chronic renal disease
• Anaemia due to chronic liver disease
• Disseminated malignancy
• Endocrinal diseases

5. Anemia Due To Bone Marrow Infiltration

• Leukemias
• Lymphomas
• Myelofibrosis/myelosclerosis
• Multiple myeloma
• Congenital sideroblastic anemia

6. Anemia Due To Increased Red Cell Destruction (hemolytic anemias)

• Intracorpuscular defect (hereditary or acquired)
• Extracorpuscular defect (Acquired)

Read And Learn More: General Medicine Questions and Answers

Morphological Classification of Anemia Based on the red cell size, hemoglobin content, and red cell indices, anemias are classified into 3 types:

1. Microcytic, hypochromic: MCV, MCH, and MCHC are all reduced, for example, in iron-deficiency anemia and in certain non-iron deficient anemias (sideroblastic anemia, thalassemia, anemia of chronic disorders).
2. Normocytic, normochromic: MCV MCH and MCHC are all normal for example, after acute blood loss, hemolytic anemias, bone marrow failure, anemia of chronic disorders.
3. Macrocytic: MCV is raised, for example, in megaloblastic anemia due to defiiency of vitamin B12 or folic acid.

 

Physiological Classification of Anemia

This is based on the reticulocyte production index:

1. Anemia with reticulocyte production count less than 2.5

• Normocytic-normochromic: Iron deficiency anemia, aplastic anemia, anemia of inflammatory, renal, and endocrine disease.
• Microcytic or Macrocytic
• Microcytic: Sideroblastic, thalassemia
• Macrocytic: Vitamin B12 or folate defiiency

2. Anemia with reticulocyte production count more than 2.5

• Hemolytic/hemorrhagic: Anemia due to blood loss,
• Hemoglobinopathies, autoimmune hemolytic, etc.

Clinical Features Of Anemia

Anemia Symptoms

• General: Lassitude and fatigue
• Gastrointestinal tract: Nausea, weight loss, anorexia, flatulence and constipation
• Cardiovascular symptoms: Palpitations, exertional dyspnea, angina, throbbing in head and ear.
• Central nervous system symptoms: Tinnitus, headache, dizziness, insomnia, numbness, tingling sensation in hand and feet.
• Genitourinary tract: Amenorrhea or menorrhagia, loss of libido.

Anemia Signs

• Presence of pallority on the skin, mucous membrane, and conjunctiva.
• Tachycardia
• The presence of a collapsing pulse
• Midsystolic flow murmur across the aortic and the pulmonary valves.
• In severe anemia, there is the presence of cardiomegaly and congestive heart failure.
• Edema can be present.

Anemia Investigations

Every case of anemia should have the following investigations to detect the degree and cause of anemia:

• Hemoglobin count decreases.
• RBC count, packed cell volume, mean corpuscular volume, and mean corpuscular hemoglobin concentration (MCHC).
• Total leukocyte count and differential leukocyte count.
• Peripheral blood film for type of anemia shape of RBCs and presence of any abnormal cells.
• Clotting time and bleeding time in hemolytic anemia.
• Blood platelets.

Bone marrow examination is done when the cause of anemia requires further investigation especially to detect the type of erythropoiesis.

Anemia Other Investigations

• Stools for parasites: A test for the presence of blood and stools is done in patients suspected of chronic blood loss.
• Urine for albumin, bile salt, pigments, and urobilinogen
• Gastric analysis: Histamine fast achlorhydria in pernicious anemia and megaloblastic anemia.
• Studies for detecting steatorrhea and malabsorption studies.
• Schilling test for vitamin B12 absorption in megaloblastic and dimorphic anemias.
• F IGLU test is done to assess folic acid defiiency. About 15 g of histidine hydrochloride is given by mouth and the urine in which it is excreted is collected over the next eight hours. Normal excretion is 1–17 mg

Anemia Management

• Correction of dietary defiiency, i.e. Faulty dietary habits, chronic alcoholism, and malnourishment.
• Treatment of underlying causes i.e. Ankylostomiasis, piles, menorrhagia, infection, chronic kidney failure, leukemia, liver disease, collagen disease or endocrine deficiency, surgical correction of intestinal abnormalities, for example, blind loop.
• Removal of toxic chemical agents or drugs, i.e. in some cases of hemolytic anemia or aplastic anemia.
• Blood transfusion: Its chief value is its immediate effect.
• Administration of substances specifically lacking, i.e.
• Haematinic should be started only after adequate blood examination, since response to a haematinic may obscure the blood picture.
• The specific hematinic should be given alone.
• The hematinic should be given in adequate doses for a sufficient period of time.