Infectious arthritis, also known as septic arthritis, is an infection in a joint that affects the fluid and tissues in the joint. The infection in the joint typically develops after an infection in some other area of the body. Germs that cause infectious arthritis can be viral, bacterial or fungal.
It is less likely that the joint infection will be caused by a than caused by bacteria or a virus. Some germs that can result in joint infections include mumps, rubella, hepatitis or HIV. In fact, 30% to 70% of people that are infected with HIV may develop a rheumatic disease as a result of the HIV virus.
Other sources of joint infection include tuberculosis (tuberculosis arthritis), human parvovirus (Fifth disease) and Lyme disease. The number of cases of Lyme disease has doubled in the last 15 years, from around 10,000 cases a year in the early 1990’s to nearly 20,000 cases more recently.
Infectious arthritis is not very common in children between the ages of 3 and adolescence, but otherwise can affect anyone of any age. Children are more often affected in the knees, hips and shoulders. Adults are more commonly affected in the weight bearing joints, such as hips, knees and ankles.
Older adults and people with chronic health conditions are more susceptible to developing infectious arthritis, as are those who already have another form of arthritis.
Our next post will cover the warning signs for infectious (septic) arthritis.