A young child is diagnosed as having acute lymphocyte leukaemia...

You've basically given the answer already. Lymphocytes (WBCs) have to go through a maturation process either in the bone marrow or thymus before they can function as mature B- or T-cells. In ALL the bone marrow releases a whopping load of immature lymphocytes, which not only are incapable of participating in an immune response, but are so numerous they can actually crowd out mature lymphocytes in the lymph nodes and impede an immune response. Thus the child is more susceptible to infection.

 
I am a survivor of Acute Lymphocytic Leukemia as of 04/07/11.

   Leukemia is most commonly known as cancer of the white blood cells. Abnormal white blood cells are produced rapidly in the bone marrow, crowding the bone marrow and flooding the bloodstream. The white blood cells help protect the body and fight off disease but the ones being produced in someone with leukemia are defective, which lowers the red blood cell count. Leukemia affects two different specific white blood cells, lymphoid, and myeloid.  (Leukemia).

   Leukemia is very common but the chance of survival are very likely after treatment. It accounts for about 30% of all childhood cancers and affect more than 3,000 American young people each year (Leukemia). Although there is still no exact cause for leukemia, it is believed to develop from genetics and environmental factors. Some of the risk factors are radiation, atomic-bomb explosions, radiation therapy, chemotherapy, diagnostic x-rays, smoking, benzene, Down syndrome and other inherited diseases, blood disorders, and family history. It is rare to have two people in the same family diagnosed with leukemia but is possible (Leukemia: Get Facts...).

   There are many symptoms for leukemia most of which will be virus like due to low white blood cell counts. Symptoms can include pain in the bones or joints, sometimes causing a limp, swollen lymph nodes in the neck, groin, or elsewhere, an abnormally tired feeling, poor appetite, fevers with no other symptoms, abdominal pain, and shortness of breath (Leukemia: Get Facts...) . Since leukemia destroys bone marrow other symptoms like easily bruised and bleeding may occur. If the cancer reaches the brain headaches, seizures, balance problems, and abnormal vision may even take place (Leukemia).

   There are many different treatments for leukemia and stem-cell therapy, radiation therapy, targeted therapy, biological therapy, and chemotherapy. Chemotherapy is the most common treatment which involves a drug that kills leukemia cells with a chemical taken either by pill or injection (Leukemia: Get Facts...).

   The alternate or alternative approaches to leukemia are acupuncture, aromatherapy, art and other expressive therapy, chiropractic, herbal remedies, massage, meditation, and prayer (Alternative Leukemia Treatment). Personally I do not believe that these approaches are effective by themselves as they do not attack the cells themselves which cannot be healed through soothing and stress relieving activities,

   There are four different types of leukemia which are classified based on the speed of progression and the type of what white blood cells are affected (Leukemia). These types are:

·         Chronic Lymphocytic Leukemia- slow progression, affects lymphoid cells

·         Chronic Myeloid Leukemia- slow progression, affect myeloid cells

·         Acute Lymphocytic Leukemia- rapid progression, affects lymphoid cells

·         Acute Myeloid Leukemia- rapid progression, affects myeloid cells