Takayasu arteritis is one of the more elusive conditions in modern medicine. It hides in plain sight — mimicking fatigue, flu, or vague musculoskeletal pain before revealing itself as a serious large-vessel vasculitis that can silently narrow arteries supplying the brain, kidneys, and limbs.

If you live with chronic fatigue syndrome, you already know the exhaustion is not the tiredness other people talk about. It is a heaviness that a full night of sleep does not lift, a fog that thickens after ordinary effort, and a body that seems to punish you a day or two after you dared to feel almost normal.