White blood cells, also known as leukocytes, are the part of the serum that forms immune system and protects against disease and foreign invaders. There are five types of white blood cells: neutrophils, lymphocytes, eosinophils, monocytes, and basophils. Each type of white blood cell has a unique function. For example, neutrophils help rid the body of bacteria and fungi, while basophils combat inflammation. A normal white blood cell count for an adult ranges between 3,500 and 10,500 blood cells per microliter (mcL) of blood.

 1. Symptoms of Abnormal White Blood Cell Count

Symptoms of a low white blood cell count include general fatigue, body aches, fever, chills, and headaches. With a low white blood cell count, cuts and bruises may not heal as quickly and are more likely to become infected. Conversely, high white blood cell levels are generally asymptomatic.

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