What are Common Causes of a Rash and Joint Pain?

Several diseases present with rash and joint pain, including chickenpox, measles, and rubella. Other chronic diseases are also associated with these symptoms, including lupus, rheumatoid arthritis, and Lyme disease. Bacterial infections, like Staphylococcus, can also cause rash and joint pain. Diagnosing a particular condition requires knowledge of the type of rash and the location of joint pain a person is experiencing.

Rashes can be flat and splotchy or consist of raised bumps. Rashes may appear all over the body, as in chickenpox or rubella, or be confined to a particular area, like the bulls-eye pattern of rash in Lyme disease. Rashes may itch or burn, or they may cause little discomfort. Rashes are most commonly caused by ingestion or contact with a substance to which a person is allergic, such as pets, poison ivy, or a particular food.

When accompanied by joint pain, however, a rash can signal a serious, even life-threatening condition. Chickenpox, measles, and rubella all present with a generalized rash and flu-like symptoms, including joint pain. Though these diseases are often thought of as rites of passage throughout childhood, they can be debilitating and even deadly if not treated properly.

Lupus and rheumatoid arthritis are conditions in which several parts of the body are affected. People with lupus often develop a malar rash, which looks like a butterfly spreading its wings across the nose and cheeks. The most common cause of a rash in people with rheumatoid arthritis is a reaction to the medications prescribed to treat the arthritis. In rare cases, RA can progress into a more dangerous disease called vasculitis, which has a distinctive rash on the fingers and toes. Both of these conditions can have intermittent joint pain, flaring up when the immune system is stressed.

Rash and joint pain can be the signs of Lyme disease if a person lives in an area where the black-legged or deer tick thrives. An infected tick can transmit Lyme disease bacteria to a person through its bite. A few days after infection, 70 percent of victims typically experience a rash called erythema migrans. This rash resembles a bulls-eye, with a red bump at the bite location, a clear area, and a red ring beyond that.

If the condition remains untreated, joint pain, especially in the knees, can develop. Like lupus and rheumatoid arthritis, this pain can be severe and intermittent. It can also travel from joint to joint throughout the body. Early detection and treatment can prevent or alleviate both the rash and joint pain that may occur with this condition.