Chronic inflammation: Your body continues sending inflammatory cells even when there is no outside danger. For example, in rheumatoid arthritis inflammatory cells and substances attack joint tissues leading to an inflammation that comes and goes and can cause severe damage to joints with pain and deformities. Several things can cause chronic inflammation, including: untreated causes of acute inflammation, like an infection or injury an autoimmune disorder, which involves your immune system mistakenly attacking healthy tissue long-term exposure to irritants, like industrial chemicals or polluted air