LEUKEMIA - Symptoms, risk factors, types and diagnosis

Leukemia is the cancer of White Blood Cells. WBC's are also known as leukocytes. Uncontrolled increase in the number of WBC's lead to a condition called Leukemia.

Our blood consists of three types of cells.i.e. Red blood cells (RBC's), White blood cells (WBC's) and platelets. Red blood cells are required to carry Oxygen from lungs to body tissues. White blood cells are required to fight against bacteria, viruses, fungi and other parasites. Due to this, WBC's prevent infections from occuring in our body. Platelets are required for blood to clot.

Blood cells are formed in the bone marrow. There are two types of cells in bone marrow - Lymphoid stem cells and Myeloid stem cells. Lymphoid cells give rise to lymphocytes which help in providing immunity. Myeloid cells give rise to Granulocytes, monocytes (types of WBC's), Red blood cells and platelets. Leukemia may be due to abnormal increase in either of the two cells.

Uncontrolled production of WBC's lead to decreased production of other blood cells. Due to this, there is deficiency of RBC's and platelets. Hence, Oxygen supply to body decreases and blood often fails to clot leading to abnormal bleeding. Also, such large amount of WBC's are abnormal and can't fight infections.

This leads to symptoms of leukemia -

• Fatigue
• Pallor
• Bleeding from nose
• Petechia (Red spots on skin).
•  Purpura (Rash or purple/red spots on the skin caused by internal bleeding).
• Recurrent infections
• Weight loss
• Night sweating

Since the bone marrow gets filled with excess of WBC's and other substances like reticulin fibres, it becomes weak. Hence, the bones become weak and person experiences pain in bones. Excess number of abnormal WBC's when released in blood from bone marrow, get accumulated in organs like Spleen, liver and lymph nodes.

All these activities lead to other symptoms like -

• Pain in bones
• Massive Splenomegaly (Enlarged spleen).
• Hepatomegaly (Enlarged liver)
• Lymphadenopathy (Swollen lymph nodes).
• Dabbing pain in abdomen due to enlarged spleen.



Risk factors for Leukemia-

There are many factors responsible for causing leukemia. They can be genetic or acquired.



• Exposure to radiation
• Chemotherapy
• Some abnormal genetic changes in chromosomes.
• Down syndrome.
• Family history of leukemia.

Many times, people are not aware that they have Leukemia since the symptoms occur gradually. Symptoms mainly occur after 5th decade of life in adults.

As mentioned earlier, there are two types of precursor cells that give rise to blood cells-Lymphoblasts and Myeloblasts. Depending on that, leukemia is of two types -

1. Lymphocytic Leukemia.
2. Myelogenous Leukemia.

Now, leukemia can be of rapidly progressing type (Acute Leukemia) or slowly progressing (Chronic Leukemia).

Hence, types of Leukemia are -

1.  1. Acute Lymphocytic Leukemia (ALL) : It is the most common type of leukemia affecting children. Cause may be genetic or acquired.

Genetic causes :-

1. Down syndrome.
2.  Fanconi anemia
   (An inheritable disease of bone marrow that leads to decreased production of all types of blood cells).
3.  Bloom syndrome
   (An inherited disorder characterized by skin rashes on exposure to sun).
4.  Ataxia telangiectasia
   (An inherited dosorder which affects brain and immune system).

Acquired causes:-

1. Radiations
2.  Infections by Epstein Barr Virus (EBV) and Human T cell Leukemia Virus 1 (HTLV1).
3. Exposure to chemicals like benzene.



It is more common is males and leads to development of testicular lump. Symptoms are same as describes above.






2.  2. Chronic Lymphocytic Leukemia (CLL):- It is the most common Leukemia in adults. More common in age group of more than 60. Radiation is not the cause of CLL.
3.  3. Acute Myelgenous Leukemia (AML): Possible risk factors for AML are Anti cancer drugs due to chemotherapy and some abnormal genetic changes in chromosomes. It is more common in people with age of 50-60 years.
4.  4. Chronic Myelogenous Leukemia (CML): It is caused by radiations and with exposure to chemicals like benzene. More common in people between the age of 40-60 years. It progresses very slowly and the person might not even know about their condition untill a blood test is done.

Diagnosis of Leukemia :

Leukemia is diagnoised by performing following tests :

1.  1. Complete Blood Count (CBC): It is performed to check the total number of blood cells. In leukemia, Total WBC count is more than 1,00,000/cmm, Whereas the normal WBC count is between 4000 - 11,000/cmm. Also the shape of WBC'c become altered and they become weak.
2.  2. Bone Marrow Examination : It is done by inserting a special kind of needle in the pelvic bone of the patient. Bone marrow is collected and examined for abnormal WBC's.
3.  3. Flow cytometry : It is a technique which is used to measure physical and chemical characteristics of a group of cells. Cancer cells being distinct from normal cells can be ey identified. Currently this method is the investigation of choice to detect blood cancer.
4.  4. Imaging tests : Imaging tests like MRI, CT scan, PET scan can spot the signs of leukemia.