You Are Here: Home > About Arthritis > Arthritis Types (A - Z) > Infectious arthritis

Infectious arthritis

Infectious arthritis is a form of joint inflammation caused by a germ. The germ is most commonly a bacterium but could be a virus or a fungus. Infection of the joints usually occurs after a previous infection elsewhere in the body.

There is usually only one joint involved, though sometimes two or three joints can become infected. Mostly, infectious arthritis affects the large joints (shoulders, hips, knees), but smaller joints (fingers, ankles) can also be involved.


What are early signs of infectious arthritis?

The symptoms of infectious arthritis vary according to the type of germ causing it. If the arthritis is caused by a bacterium, inflammation is generally located in only one place or area. The infection is often accompanied by fever and chills and its onset is quite sudden. With infectious arthritis caused by a virus, there is usually no fever, but there is an aching feeling all over the body. Inflammation caused by a fungal infection can be in one area or throughout the body, and it usually occurs very slowly, over weeks or months. You may have a mild fever or no fever at all.

How is infectious arthritis diagnosed?

Establishing the correct diagnosis is important, so if your doctor thinks you have infectious arthritis, he or she may ask questions about the symptoms, other medical conditions, recent travel, illnesses, and contact with people who may have had infections. He or she may also perform a physical examination, and order x-rays and other tests to find out what germ is causing the infection. This can be done by using a needle to removing a sample of fluid from the affected joint so it can be examined.

If tuberculosis or a fungus is the suspected cause, sometimes a small piece of tissue from the joint may need to be cut away and examined (a procedure called a biopsy). If a virus is suspected, a blood test may be done because your body develops cells called antibodies to fight off the virus. These antibodies will show up in a blood test.

What are the risk factors for infectious arthritis?

With infectious arthritis a germ has travelled through the body to a joint. The germ may have entered the body through the skin, nose, throat or ears, or through an existing wound.

Usually, there has already been an infection elsewhere in the body. For example, if you develop infectious arthritis from the bacterium pneumococcus, which causes pneumonia, you may have already experienced pneumonia in the lungs. After the initial infection, the germ can travel through the bloodstream to the joints, where it then settles and causes inflammation.

Bacteria cause most cases of infectious arthritis. The types of bacteria that might cause such infection include:

  • gonococcus
  • staphylococcus
  • streptococcus
  • pneumococcus
  • haemophilus
  • spirochetes
  • tuberculosis

Certain viruses can also cause infectious arthritis. They include:

  • hepatitis viruses
  • mumps
  • rubella

Fungi are the least common cause of infectious arthritis. They are usually found in:

  • soil
  • bird droppings
  • certain plants, such as roses

Infectious arthritis is not transmittable from one person to the other, but some germs (such as those causing gonorrhea) can be spread by person-to-person contact. However, while these diseases can be passed on, this does not automatically mean the development of infectious arthritis.

How common is infectious arthritis?

Any person, at any age, can get infectious arthritis. However, some people are more likely to get infectious arthritis than others. These include people living with conditions that make it difficult to fight off infection, such as:

  • diabetes
  • sickle-cell anaemia
  • severe kidney disease
  • AIDS
  • immune deficiency
  • some forms of cancer
  • alcoholism
  • intravenous drug abuse

People with an existing arthritis are also more likely to develop infectious arthritis, because germs tend to infect a joint that is damaged, and therefore weaker than a healthy one. If a person has had surgery to replace a joint with an artificial one, this can also provide a slight chance of infection developing. If it does, it usually occurs a short time after the surgical procedure. However, it is not unheard of for infection to show up in a person months or years after having joint replacement surgery.

Some of the stronger medications used to treat certain types of inflammatory arthritis also lower the body's resistance to infection, making it easier for infectious arthritis to take hold.

People who work in jobs where exposure to animals, plants, marine life and soil is common also may have a higher chance of contracting infectious arthritis.


Infectious arthritis is usually not a long-term illness. Most of the time it can be cured if it is treated promptly and properly. Without treatment however, the affected joints can become damaged soon after the infection starting and the infection can spread to other parts of the body.

People with infectious arthritis may be put in the hospital for treatment, particularly if the doctor decides intravenous antibiotics should be started. Sometimes affected joints must be drained of excess fluid that has built up. This is done by inserting a needle directly into the joint. Sometimes the same joint may need to be drained several times if fluid build-up recurs. For some joints (e.g. hip, shoulder), this may require an operation such as arthroscopy to adequately drain the fluid from the infected joint. Further treatment varies depending on what type of germ has caused the infection.

If infection is considered, fluid is taken from the infected for culture. The decision on which treatment to use depends on the results of the joint fluid cultures.


Arthritis medications are designed to control a disease, slow its progression, and to protect the joint. The best outcomes for infectious arthritis occur when the treatment is started promptly and when the correct antibiotic for the particular infection is used

To explore this area of treatment, The Arthritis Society has developed a comprehensive expert guide that delivers detailed information on medications used to treat arthritis.

EXPLORE: Arthritis Medications – A Reference Guide

The optimal treatment is what is best in each individual case – so speak with your doctor and/or pharmacist about what kind of medications are most appropriate for you.


Occasionally an infected joint will need to be thoroughly drained and washed out. This may best be done with an operation by an orthopedic surgeon. This is particularly true of infected hip joints.


In instances where diagnosis and treatment were delayed and joint damage from infectious arthritis has developed, additional assistance may be required to help restore mobility and quality of life after the infection has been cured. These healthcare professions have advanced training from a university and are registered to practice by their provincial/territorial association.

A physiotherapist (PT) can develop an individualized program designed to help you increase your strength, flexibility, range-of-motion, and general mobility and exercise tolerance through a wide variety of therapeutic treatments and strategies. These include exercise prescription, physical interventions, and relaxation, in addition to advising you on other techniques for reducing pain and increasing your overall quality of life. PTs can also refer you to other health professionals and community services for further measures that will help you adapt to your changing circumstances.

An occupational therapist (OT) trained in arthritis management can analyze everything you do in a day and develop a program to help you protect your joints and minimize fatigue. If necessary, your OT can help you redesign your home or workplace to make it easier for you to work or simply get around. They can also make or recommend a number of different splints, braces, orthopedic shoes and other aids that can help reduce your pain and increase your mobility and functionality. Their goal is to prepare you, using assistive devices and adaptive strategies, to reclaim as much of your former life as possible.


The first function of self-management for infectious arthritis is prevention, which comes down to avoiding exposure to potential infections. It is also important to seek medical attention promptly if symptoms suggesting infectious arthritis have occurred. If there has been a delay in receiving diagnosis and treatment, joint damage may have accumulated, affecting your mobility and quality of life. However, there are things you can do to live better with the disease. Although you can undertake many of these activities on your own, it is important to assemble a health-care team who can help oversee and direct your self-management efforts.

Physical activity

Physical activity is any activity that uses your muscles and increases your heart rate. Physical activity strengthens your heart and lungs, and improves your mobility. Participating in a properly designed exercise program can help alleviate some of the pain or discomfort associated with inflammatory forms of arthritis. So can activities that you do as a part of everyday life – such as vacuuming the house, walking to work, even gardening.


After treatment of infectious arthritis, people often experience muscle weakness around the affected joint: exercise is important to recondition those muscles. Exercise is physical activity that involves heavier, repetitive exertion, and is designed to improve or maintain physical fitness. Lifting weights, running on a treadmill, taking a yoga class – these are the kinds of planned motions that we do specifically to improve our flexibility, strength or endurance. Being physically active can reduce pain and fatigue, improve mobility and overall fitness, and improve your state of mind by allowing you to actively participate in your own treatment.

For more information about arthritis, physical activity and exercise, visit our Exercise & Motion page.

Relaxation and coping skills

Developing good relaxation and coping skills can help you maintain balance in your life, giving you a greater feeling of control over your arthritis and a more positive outlook. There are many ways to relax. Try deep breathing exercises. Listen to music or relaxation tapes. Imagine or visualize a pleasant and restful activity, such as lying on a beach.

For more information about relaxation and coping skills, visit our Pain Management page.

What Now

Living well with arthritis

There is a lot you can do to take control and actively manage your arthritis. Below we have listed a few resources to help you learn more about actively managing your arthritis to live better.


To find health & wellness advice, self-management tips, inspirational stories, and much more.

Explore Flourish

Online Learning

Our online courses are jam-packed with helpful tips and information.  Each course is devoted to a specific issue or symptom linked to arthritis.

Discover Arthritis Courses

Workshops and Webinars

Learn about upcoming educational events and webinars.

Find Workshops and Webinars

Navigating Through Arthritis

Learn about information and services available.

Navigate through arthritis


This information was last updated September 2017, with expert advice from:

Dr. Rob Inman, MD
Senior Scientist, Krembil Research Institute, University Health Network
Professor of Immunology and Medicine, Faculty of Medicine, University of Toronto

View All Arthritis Types (A - Z)