👉 Nephritis, also known as nephritis, is a condition that occurs when the blood vessels of the kidneys become inflamed and swollen. This can lead to a variety of symptoms, including pain, swelling, and fever. Nephritis is often caused by an immune response against the kidney or its components, such as protein crystals in the bloodstream or a buildup of fluid in the kidneys. It is a common cause of kidney disease and can be life-threatening if not treated promptly.