A thyroid-stimulating immunoglobulin (TSI) test is a blood test that can help diagnose Graves’ disease, an autoimmune condition that causes an overactive thyroid. A TSI test measures levels of TSIs in ...

This article was reviewed by Felix Gussone, MD. If you’ve been feeling a bit more couch potato than go-getter lately, dragging through the day, snapping at people for no reason, or wondering where ...

Your doctor may recommend the creatine phosphokinase (CPK) test if there's a need to measure CPK enzyme levels in your blood. The cells in your body require this creatine kinase enzyme to generate ...

Lindsay Modglin is a nurse and professional writer who regularly writes about complex medical topics, as well as travel and the great outdoors. She holds a professional certificate in scientific ...