Conditions & Treatments

Infectious Arthritis

Infectious arthritis is an infection in the joint (synovial) fluid and joint tissues.

Infectious Arthritis

What is infectious arthritis?

Anatomy of the hip joint
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Infectious arthritis is an infection in the joint (synovial) fluid and joint tissues. The infection usually reaches the joint(s) though the bloodstream, although some joints may become infected due to an injection, surgery, illness (such as pneumonia), or injury. Different bacteria and viruses can infect a joint and usually are associated with a person's age, including the following:

  • Staphylococci (a common bacteria that often causes skin infections), Haemophilus influenzae (a bacteria that can infect the larynx, trachea, and bronchi), and gram-negative bacilli (a group of bacteria, including Escherichia coli, or E. coli) are usually associated with young children and infants.

  • Gonococci (the bacteria that causes gonorrhea), staphylococci, and streptococci (a group of bacteria that can lead to a wide variety of diseases) are usually associated with older children and adults.

  • Viruses, such as the HIV, tend to infect the joints of people of all ages.

What are the symptoms of infectious arthritis?

The most common joints affected by infectious arthritis are the knee, hip, shoulder, elbow, wrist, and finger. Most infections only affect one joint. The following are the most common symptoms of infectious arthritis. However, each individual may experience symptoms differently. Symptoms may include:

  • Fever

  • Joint pain

  • Joint swelling

The symptoms of infectious arthritis may resemble other medical conditions or problems. Always consult your doctor for a diagnosis.

How is infectious arthritis diagnosed?

Prompt diagnosis of infectious arthritis is necessary to prevent permanent damage to the joint. In addition to a complete medical history and physical examination, diagnostic procedures for infectious arthritis may include the following:

  • Removal of joint fluid to examine for white blood cells and bacteria

  • Blood tests to detect bacteria

  • Phlegm, spinal fluid, and urine tests to detect bacteria and find the source of infection

Treatment for infectious arthritis

Specific treatment for infectious arthritis will be determined by your doctor based on:

  • Your age, overall health, and medical history

  • Extent of the condition

  • Your tolerance for specific medications, procedures, and therapies

  • Expectation for the course of the disease

  • Your opinion or preference

Infectious arthritis usually requires immediate treatment with antibiotics, which can often improve symptoms within 48 hours. However, certain infections caused by fungi need treatment with antifungal medications, while viral infections usually have to run their course without treatment. To prevent accumulation of pus from the infection, which can damage the joint, the pus may be drained with a needle, tube, or surgery. Other treatment may include:

  • Medications to reduce pain and fever

  • Physical therapy

  • Splinting the joint to relieve pain

Treatment Programs


Massachusetts General Hospital understands that a variety of factors influence patients' health care decisions. That's just one reason why we're dedicated to ensuring patients understand their diagnosis and treatment options. Because a single option might not serve all patients, we offer a wide range of coordinated treatments and related services across the hospital. Patients should consult with their primary care doctor or other qualified health care provider for medical advice and diagnosis information.

Select a treatment program for more information:



Imaging

  • Pediatric Imaging
    The Pediatric Imaging Program at Massachusetts General Hospital Imaging specializes in ensuring the safety and comfort of child patients while providing the latest technology and the expertise of specialized pediatric radiologists.
  • Bone and Joint Imaging and Intervention
    The Bone and Joint Imaging and Intervention Program at Massachusetts General Hospital Imaging offers state-of-the-art diagnostic exams including MRI and CT, interpretation by specialty-trained radiologists, and image-guided procedures for the bones, joints, and spine.
MassGeneral Hospital for Children

  • Pediatric Rheumatology Program
    Pediatric rheumatologists at MassGeneral Hospital for Children specialize in the diagnosis and treatment of all rheumatic and inflammatory conditions of infants, children and adolescents.
Department of Orthopaedics

  • Hip & Knee Replacement Service
    Our Best of Boston joint replacement surgeons specialize in innovative approaches to total hip replacement and total knee replacement using a variety of minimally invasive techniques and new materials developed by our Harvard faculty.

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