There are five kinds of white blood cells--lymphocytes, monocytes, neutrophils, eosinophils and basophils. Overall, these cells have the responsibility of protecting you against infections. They fight and destroy what they consider to be foreign invaders. In this fight, they have a "division of labor." But there are times when cancer develops because high numbers of clones reproduce.
In asthma, the airways are too responsive to allergens, the foreign substances that can trigger an allergic response. According to Dr. Russell Blair of Wake Forest University Baptist Medical Center in "The Merck Manual for Healthcare Professionals," the airways will become irritated. This leads to inflammation, and the smooth muscle within the airway gets thicker. But now, because the muscle has increased in size, the opening within the airway is smaller. This only makes it react even more and causes it to become swollen. As part of the response to the allergen, in the fight against the foreign invader, the white blood cells will increase in numbers, especially the eosinophils.
Helminths are worms--roundworms, tapeworms and flukes. There are many helminths that infect humans. In response to this type of infection, white blood cells increase their numbers to destroy the parasite. Specifically, the number of eosinophils increases. They surround the worm and use a substance within their cell, called a granule, to destroy it. Dr. Andrew Wardlaw, professor of respiratory medicine at Leicester University Medical School writes in "Williams Hematology" that the most common cause for an elevated number of eosinophils worldwide is due to helminthic infections.
Infectious mononucleosis is a viral infection that is caused by a virus with the name of Epstein-Barr. The symptoms include sore throat, fever, swollen lymph nodes and extreme fatigue. But this viral infection will also lead to an enlarged spleen. The number of white blood cells increases so that they enlarge the spleen. Dr. Vicente Corrales-Medina, infectious-diseases fellow at the Baylor College of Medicine in "Current Medical Diagnosis & Treatment," writes that more than 50 percent of the white blood cells attacking this infection will be lymphocytes. At least 10 percent are referred to as "atypical" lymphocytes because they are bigger than their usual size.
According to the Centers for Disease Control and Prevention, 34,316 people were diagnosed with leukemia in 2006, and 22,016 people died from it. Leukemia is a type of blood cancer. Abnormal white blood cells reproduce. This results in high numbers of abnormal clones. The disease is classified into acute leukemia and chronic leukemia. In acute leukemia, there are high numbers of immature white blood cells. The disease progresses quite rapidly. In chronic leukemia, there are high numbers of mature white blood cells, and the cancer will develop at a more gradual pace. While leukemia in general involves an elevated white blood cell count, different types of leukemia will have an increase in specific types of white blood cells. In acute lymphocytic leukemia and chronic lymphocytic leukemia, there are high numbers of lymphocytes. There are elevated numbers of neutrophils, eosinophils and basophils in acute myelogenous leukemia and chronic myelogenous leukemia.
- Centers for Disease Control and Prevention: Leukemia Statistics
- “Current Medical Diagnosis & Treatment 2009”; Stephen McPhee, M.D., Maxine Papadakis, M.D.; 2009
- The Merck Manual for Healthcare Professionals: Asthma
- “Williams Hematology”; Marshall Lichtman, M.D., Ernest Beutler, M.D. et al.; 2006