Advanced Patient Assessment Practice Exam

What is the normal percentage range of lymphocytes in circulating white blood cells?

1. 20% - 45%

2. 50% -70%

3. 5% - 10%

4. 10% - 20%

The correct answer is: 20% - 45%

Lymphocytes play a crucial role in the immune system, primarily involved in the body's defense against infections and diseases. In adults, the normal percentage of lymphocytes in circulating white blood cells typically ranges from 20% to 45%. This range reflects the balance of different types of white blood cells, which include lymphocytes, neutrophils, monocytes, eosinophils, and basophils, each serving distinct functions. The percentage of lymphocytes can be an important indicator of immune health. Elevated lymphocyte counts may indicate viral infections or certain chronic conditions, while lower counts can suggest issues such as stress, immunosuppression, or acute infections. In contrast, the other ranges presented do not accurately reflect typical levels of lymphocytes in adults. A range of 50% to 70% would suggest an abnormally high count, while 5% to 10% and 10% to 20% are both lower than the established normal range, potentially indicating an immunological concern. Understanding these values is essential in assessing patient health and guiding diagnostics in clinical practice.