Aplastic Anemia vs Hemolytic Anemia
Blood contains red blood cells (RBCs), which contain an iron rich protein called haemoglobin. Haemoglobin carries oxygen from the lungs to the rest of the body and removes the carbon dioxide from the cells. In anemia, there is a decrease in the RBCs. Hence, there is a decreased oxygen carrying capacity of blood. The bone marrow is a sponge like tissue present inside the bones. It is responsible for producing RBCs, white blood cells (WBCs) and platelets.
Aplastic anemia is a condition in which the bone marrow is damaged and affects the blood cell production. The bone marrow stops producing blood cells whereas Hemolytic anemia is a condition in which there is excessive breakdown of the RBCs. The RBCs are destroyed before their normal lifespan of 120 days. The destruction of RBCs is called hemolysis and thus the name. Aplastic anemia involves all the blood cells whereas Hemolytic anemia involves only the RBCs.
Aplastic anemia is caused due to exposure to chemotherapy, radiotherapy which is used in cancers; chemicals like insecticides,benzene; use of drugs like chloramphenicol, antibiotics; infections like Hepatitis, Parvovirus etc whereas hemolytic anemia is seen in hereditary defects in the red cell membrane or haemoglobin or the enzymes that maintain the RBCs. Enzymes are proteins that cause chemical reactions in the body. Haemolytic anemia occurs in Thalassemia and deficiency of enzyme G6PD (glucose 6-phosphate dehydrogenase). In thalassemia, there is a defect in haemoglobin and abnormal RBCs are produced. These RBCs are fragile and break easily. Haemolytic anemia also has auto-immune causes i.e. our immune system attacks the RBCs and they break down easily. It is triggered due to exposure to chemicals; use of drugs like penicillin, quinine and overactive spleen.
In both conditions, patient develops symptoms of anemia like weakness, fatigue, breathlessness. In aplastic anemia, there is a tendency to infections, easy bruising, nasal and gum bleeding whereas in haemolytic anemia, there is jaundice (yellowing of the skin/eyes), dark urine and enlargement of the liver and spleen. During breakdown of RBCs, a yellow pigment called bilirubin is released causing jaundice.
We can diagnose aplastic anemia by tests like complete blood count (CBC), and bone marrow biopsy. CBC shows decreased haemoglobin, RBCs, WBCs and platelets whereas in haemolytic anemia, CBC shows decreased RBCs but increased white blood cells, platelets and reticulocytes. Other tests to detect haemolytic anemia include Serum lactate dehydrogenase, Serum Haptoglobin, Urine tests and Liver function test which show increased bilirubin levels.
Treatment of aplastic anemia includes blood transfusion, antibiotics to control infection and immunosuppressants (Drugs that suppress the activity of the immune cells that damage the bone marrow). Bone marrow transplant is preferred in young patients. Treatment of haemolytic anemia depends on the cause. In hereditary defects, folic acid supplementation and blood transfusion is done. In autoimmune conditions, corticosteroids are used. In severe cases, removal of spleen is suggested.
Summary
In Aplastic anemia, the bone marrow is damaged and stops producing blood cells. It is caused by exposure to chemotherapy, infections, chemicals, drugs etc. Symptoms include weakness, tendency to infections, easy bruising and bleeding. It is diagnosed on CBC and bone marrow biopsy. Treatment includes blood transfusion, immunosuppressants and bone marrow transplant.
In hemolytic anemia, there is excessive breakdown of the RBC’s. The RBC’s are destroyed before their normal lifespan. It is caused due to defect in the cell membrane, haemoglobin or enzymes. Patient develops tiredness, breathlessness, jaundice, dark urine etc. Diagnosis is done by CBC, liver profile, urine test etc. Treatment includes corticosteroids, blood transfusion and folic acid supplements. In severe cases, removal of spleen is advised.