Prurigo nodularis is a type of disease that causes firm bumps or nodules on the skin. It is usually associated with other underlying skin issues, insect bites, bacterial infections, or health concerns like HIV, kidney failure, liver or thyroid disease, or even diabetes. Although more common in adults in the 40–69 age group, it can affect people of all ages. But, the condition is treatable, and recognizing its symptoms can help make the management easier. Warning signs Prurigo nodularis is not a hereditary or contagious disease. It affects both males and females, causing skin issues in one or more  parts of the body .  To avoid complications , it is important to recognize and address these signs as soon as one notices them. 1. Bumps on the skin One of the most obvious signs of prurigo nodularis is bumps on the skin. The bumps are usually thick, dry, and crusty on the top and can itch quite often, even at night,  which can disrupt  sleep. The number of bumps can vary, and one may find them scattered across the body or in just certain patches of skin. The size of nodules can range from a few millimeters to more than three centimeters across,  which is  about 0.2–1.2 inches.