Septic arthritis, also called as infectious arthritis, is an inflammation of synovial membrane due to bacterial infection. It is characterized by inflammation, severe pain, swelling in the affected joint accompanied by fever and chills. Different types of bacterial infections are the major causes of septic arthritis (infectious arthritis).
Causes of septic arthritis (infectious arthritis) vary according to the age group of a person. Septic arthritis (infectious arthritis) affects infants, young and adult people equally and symptoms are also similar. As the name suggests, this diseased is associated with infections. Staphylococci, hemophilus influenzae, gram-negative bacilli, gonococci, staphylococci, and streptococci are some of the significant bacteria responsible for the spread of septic arthritis (infectious arthritis).
When bacterial infection occurs in any part of body, bacteria from the infected area can enter the bloodstream and then get transported all over the body. These bacteria can enter the joints through the blood stream. If they are not immediately destroyed, they can give rise to infection leading to inflammation of joints. Although exact causes of septic arthritis (infectious arthritis) are unknown, joint injury is likely to trigger infection of joints. Puncture wounds, drug injections and surgery are other possible causes of septic arthritis.
Staphylococcal infection is one of the important causes of septic arthritis (infectious arthritis). This bacterium can destroy the cartilage in the joints. Destruction of cartilage and bone can give rise to dislocations of joints and bones. The bacterial infection can spread into blood and surrounding tissues and cause abscesses or even blood poisoning leading to septic shock.
Risk factors for septic arthritis are simultaneous bacterial infection, medications or diseases causing suppression of immune system, chronic illness, intravenous drug abuse, sickle cell disease, rheumatoid arthritis, recent joint injury, artificial joints, recent joint arthroscopy or other invasive surgery. Younger children and older adults are at the higher risk of developing this disease. Besides this, alcoholics and homosexuals are more prone to this disease. In addition to that, those who have undergone any kind of surgery or have taken injections in the joints are more susceptible to this disease. If a person has weak immune system because of HIV or other infections, he is more vulnerable to this disease.
Low-birth babies are more prone to bacterial infections, most commonly streptococcal infection. Staphylococcal infection can commonly occur during hospitalization. Such infections can lead to septic arthritis. In older children or adults, the organisms like Streptococcus viridans and Streptococcus pyogenes as well as Staphylococcus aureus are responsible for joint infections associated with joint surgery. Teenagers and adults may frequently develop septic arthritis from Neisseria gonorrhoeae infections. Older adults infected by gram-negative bacilli such as Pseudomonas and Salmonella are commonly susceptible to joint infections.
