SYMPTOMS, ETIOLOGY, & OCCURENCE

Symptoms
1. Anemia
Caused by red blood cell production is less a result of the failure of the bone marrow to produce red blood cells. Characterized by reduced hemoglobin concentration, a decrease in hematocrit, red blood cell count less. Children with leukemia have pale, tiredness, shortness of breath sometimes.

2. High body temperature and easy to infections
Due to a decrease in leukocytes, it will automatically lower the body resistance due to leukocytes serves to maintain the immune system can not work optimally.

3. Bleeding
Signs of bleeding can be viewed and analyzed from the presence of mucosal bleeding such as gums, nose (epistaxis) or bleeding under the skin which is often called petechiae. Bleeding may occur spontaneously or due to trauma. If very low levels of platelets, bleeding can occur spontaneously.

4. Decreased consciousness
Due to infiltration of abnormal cells to the brain can cause a variety of disorders such as seizures to coma.

5. Decrease in appetite

6. Weakness and physical exhaustion.

Etiology 

The cause of ALL until now not clear, but most likely due to a virus (oncogenic viruses).
Other factors that play a role include:

1. Exogenous factors such as X rays, radioactive rays, and chemicals (benzol, arsenic, sulfate preparations), infections (viruses and bacteria).
2. Endogenous factors such as race
3. Constitutional factors such as chromosomal abnormalities, hereditary (sometimes encountered cases of leukemia in siblings or twins one egg).

Predisposing factors:

1. Genetic factors: a certain virus causes changes in gene structure (T cell leukemia-lymphoma virus / HTLV)
2. Ionizing radiation: the work environment, prenatal care, previous cancer treatment
3. Exposure to chemicals such as benzene, arsenic, chloramphenicol, phenylbutazone, and anti-neoplastic agents.
4. Immunosuppressive medications, drugs carcinogens such as diethylstilbestrol
5. Hereditary factors such as the twins one egg
6. Chromosomal abnormalities

If the cause of leukemia is caused by a virus, the virus will easily fit into the human body if the structure of the viral antigen is consistent with the structure of the human antigen. The structure of the human antigen is formed by the antigen structure of various organs, especially the skin and mucous membranes located on the surface of the body (tissue antigen). By WHO, tissue antigens defined by the term HL-A (human leucocyte locus A). 

Occurence

Since leukemia is always fatal, the mortality rates are a reasonably accurate reflection of the occurrence of the disease at various ages. Certain features about the occurrence of leukemia were analyzed from the Vital Statistics of the United States over a twenty year period with special reference to age. A comparison of the occurrence (mortality) during this time has shown a considerable and progressive increase in incidence in persons over 50 years of age from 1930 to 1949. In ages under 50 years the increase was apparently slight but not remarkable.

In addition a comparison of the clinical occurrence of patients with the chronic forms of leukemia has shown that, in recent years, the proportion of patients over 50 years of age is twice as great as in similar groups of patients observed some twenty years previously.

The evidence strongly suggests that the occurrence of leukemia in persons over 50 years of age is actually increasing.