Doctors and medical professionals must analyze the results of blood tests ordered because of lymph node swelling. Lymph nodes may become enlarged due to problems such as cancer, injury or infection, notes the American Cancer Society. Blood test results are interpreted based on the test requisitioned. A Complete Blood Count is understood through comparison with normal ranges, for example, while a White Cell Differential may suggest illness by revealing white cells in abnormal patterns, says the Leukemia & Lymphoma Society.
A Complete Blood Count, or CBC, measures the number of white cells, red cells, and platelets in one's blood. It also provides hematocrit and hemoglobin levels, according to the Leukemia & Lymphoma Society. Results outside of normal ranges for the CBC may indicate health issues. Lymph node enlargement is frequently caused by something other than cancer, notes the American Cancer Society.
By helping to determine the normalcy in number and appearance of platelets, white cells, and red cells, a blood smear can suggest an underlying condition, its severity and the need to test further. Chemistry panels are used to investigate blood chemistry. These tests can provide information concerning one's health by measuring things such as the levels of cholesterol, blood glucose, protein and certain vitamins. The presence of certain blood proteins in higher levels can indicate disease severity, and high uric acid levels may indicate the presence of illness.