What is referred to as "getting heated" generally refers to the appearance of herpes around the mouth. In fact, most people carry the herpes virus, which typically does not flare up under normal circumstances. However, when the body's immune system is weakened, the virus can become active. For example, factors like long-term fatigue, lack of sleep, or other illnesses can lead to the reemergence of these sores. They can also appear during acute nephritis, as this condition involves kidney abnormalities or possible symptoms like blood and protein in the urine. Some patients may also experience reduced urine output and acute kidney failure. During acute kidney failure, the immune system is often weakened, which can lead to the reappearance of herpes around the mouth, commonly known as "getting heated."