Leukopenia

Leukopenia is a condition wherein the leukocyte count in the blood is low. Low WBC or White Blood Cells indicate decrease in disease fighting cells circulating in the blood. Some of the common causes for low WBC count:

Viral infections Any viral infections may disrupt bone marrow function for a short duration thus producing low counts of white blood cells. Infections like typhoid, influenza may lower the white blood cell count.

Congenital disorders may weaken bone marrow function, a WBC spectrum test can confirm any such congenital disorder.

Kostmann's syndrome is a congenital disorder wherein the neutrophil production is low.

Myelokathexis Neutrophils fail to enter the blood stream.

Infectious disease HIV destroys the WBC and leaves the person susceptible to infections.

Malnutrition

Vitamin or mineral deficiencies

Parasitic diseases

Autoimmune disorders may destroy white blood cells or bone marrow cells.

Aplastic anemia In this condition the bone marrow does not produce enough of any of the cells including white blood cells. This condition may set in all of a sudden or can develop and progress gradually. Few drugs, pregnancy, radiation therapy or chemotherapy can trigger this condition.

Lupus is an auto immune disease wherein the body fights with its own immune system thus destroying white blood cells.

Chemotherapy and radiation therapy are used to kill cancerous cells. They however destroy healthy white blood cells thus leaving the patient with low WBC count. This is one major reason why cancer patients are unable to fight diseases or infections in general.

Leukemia is a type of cancer wherein the body produces too many white blood cells that are abnormal. These white blood cells are not active white blood cells that can fight infections. People down with leukemia have low white blood cell count as their bone marrow is producing more of the abnormal white blood cells.

Cancer may also damage the bone marrow.

Hyperthyroidism An overactive thyroid can produce lower number of white blood cells. The medication used for thyroid can reduce the white blood cell count in the blood.

Liver disorder/Spleen disorder Hypersplenism, in which blood cells are destroyed prematurely by the spleen. An enlarged spleen also known as splenomegaly can trigger low white blood cell count.

Leptospirosis

Leptospirosis is a bacterial infection caused by Leptospira interrogans bacterium. This is also known as infectious jaundice, swamp fever and hemorrhagic jaundice . Leptospirosis is more prevalent in tropical areas especially in areas where there are animals or rodents in urban dwellings. This infection spreads through contact with water, food, or soil containing urine from infected animals. It usually does not spread from person to person.

Typical symptoms of Leptospirosis include high fever, muscle aches, vomiting and jaundice. The patient might suffer chills and headache. Other symptoms of leptospirosis are diarrhea, abdominal pain and skin rash. Left untreated, leptospirosis can lead to meningitis, kidney failure and liver failure. Since the symptoms are not very specific, this disease is likely to be neglected. A blood test for Leptospirosis is done to diagnose the infection. This will show increased liver enzymes and WBC count of less than 10,000. A urine analysis will show abnormality. Leptospirosis is treated with antibiotics, such as doxycycline or penicillin.

CD4 Count Test

The CD4 Count Test is an indicator of the working of the immune system. By measuring the number of CD4 T lymphocytes or CD4 cells in the blood, it helps to predict and assess the progression of HIV. This count helps in planning antiretroviral therapy or ART. Monitoring the CD4 count through regular blood tests helps to determine the efficacy of the ART and whether the patient is at risk for other infections.

The CD4 lymphocytes are WBC that play a vital role in infection protection. HIV virus tag on to CD4 cells to propagate and spread the infection within the body. Thus an infected person will notice a reduced count of CD4 cells (less than 200 cells/mm3) when the normal range of CD4 cells is from 500 cells/mm3 to 1,200 cells/mm3.

Successful ART results in reduced CD4 count and lesser viral load in the blood. CD8 cells are another type of WBC that work against infections in the body including HIV.