This test looks for a substance that can appear in your blood if you have hairy cell leukemia.

This test measures the level of the hormone thyroxine (T4) in your blood. This test can show your healthcare provider whether your thyroid gland is overactive (hyperthyroidism) or underactive (hypothyroidism).

This test finds and counts 3 types of white blood cells in your blood. White blood cells help your body fight off infections and illness.

This test looks for antibodies that your body made when fighting off group A Streptococcus bacteria. These bacteria cause strep throat.

This test looks for white blood cells in your stool. This can help your healthcare provider figure out what's causing inflammatory diarrhea.

This test looks for bacteria, viruses, and other organisms in your stool. This test can help find out what's causing a digestive tract infection.

This test finds out what's causing your lung infection. Sputum, or phlegm, is the mucus that settles in the lower airways of your lungs when you have an infection or a chronic illness.

This test measures the amount of sodium, or salt, in your urine. This test can help your healthcare provider find out whether you have too much salt in your diet.

This test measures how much sodium you have in your blood. Too much or too little can lead to health problems like high blood pressure.

This test measures the level of a substance called rheumatoid factor in your blood. It helps your healthcare provider find out whether you have rheumatoid arthritis.