Nephritis is a condition characterized by inflammation of the kidneys. It can be caused by various factors, including infections, autoimmune diseases, and certain medications. Nephritis can result in symptoms such as blood in the urine, swelling in the legs and feet, high blood pressure, and fatigue. Treatment for nephritis typically involves managing the underlying cause of the inflammation, as well as medications to reduce swelling and control blood pressure. If left untreated, nephritis can lead to permanent kidney damage and chronic kidney disease.