Septic arthritis

Description

Septic arthritis is a painful infection of a joint that can come from germs that travel through your bloodstream from another part of your body. Septic arthritis can also occur when a penetrating injury, such as an animal bite or trauma, delivers germs directly into the joint.

Infants and older adults are more likely to develop septic arthritis. People who have artificial joints are also at risk of septic arthritis. The knees are most commonly affected, but septic arthritis can also affect the hips, shoulders and other joints. The infection can rapidly and cause severe damage to the cartilage and bone within the joint, so that the appropriate treatment is crucial.

The treatment consists of drainage of the joint with a needle or during surgery. Antibiotics are also often necessary.

Symptoms

Septic arthritis usually causes extreme discomfort and difficulty in the use of the affected joint. The joint may be swollen, red and hot, and you might have a fever.

If septic arthritis occurs in an artificial joint (prosthesis joint infection), signs and symptoms, such as minor pain and swelling can develop months or years after the knee replacement or hip replacement surgery. Also, a loosening of the joints can occur, causing pain, while the movement of the joints or, while putting weight on the joint. Typically, the pain disappears when it is at rest. In extreme cases, the joint can become dislocated.

When to see a doctor

Consult your doctor if you have severe pain in the joints that occurs suddenly. Timely treatment can help to minimize the damage to the joints.

If you have an artificial joint, see your doctor if you experience pain, while the use of the joint.

Causes

Septic arthritis can be caused by bacteria, viruses or fungal infections. Bacterial infection with Staphylococcus aureus (staph) is the most common cause. Staph bacteria commonly live on healthy skin.

Septic arthritis can develop when there is an infection, such as a skin infection or urinary tract infection, spreads through the bloodstream to a joint. Less commonly, a puncture wound, drug injection, or surgery in or near a joint, including the joint replacement surgery — you can give germs the entry into the joint space.

The lining of the joints has little ability to protect themselves from infection. The reaction of the body to infection, including inflammation which can increase the pressure and reduce the flow of blood within the joint, which contributes to the damage.

Risk factors

Risk factors for septic arthritis include:

  • Existing problems in the joints. Chronic diseases and conditions that affect the joints, such as osteoarthritis, gout, rheumatoid arthritis or lupus can increase the risk of septic arthritis, as can previous joint surgery and the injury of the joint.
  • To have an artificial joint. Bacteria may be introduced during the joint replacement surgery, or an artificial joint can become infected if the bacteria travel to the articulation of different areas of the body through the bloodstream.
  • Take medications for rheumatoid arthritis. People with rheumatoid arthritis have a greater increase in the risk due to the medications that you take, that can suppress the immune system, making infections more likely to occur. The diagnosis of septic arthritis in people with rheumatoid arthritis is difficult because many of the signs and symptoms are similar.
  • The fragility of the skin. The skin breaks easily, and heals poorly, you can give bacteria access to your body. Skin conditions such as psoriasis and eczema increase the risk of septic arthritis, such as make-infected skin wounds. People who regularly inject drugs are also at an increased risk of infection at the injection site.
  • Weak immune system. People with a weak immune system are at greater risk of septic arthritis. This includes people with diabetes, kidney and liver problems, and those who are taking medications that suppress the immune system.
  • Joint Trauma. Animal bites, puncture wounds or cuts of more than one joint can put you at risk of septic arthritis.

Have a combination of risk factors that put you at greater risk of having a risk factor does not.

Complications

If you delay the treatment, septic arthritis can lead to degeneration of the joint and permanent damage. If septic arthritis affects an artificial joint, complications may include joint loosening or dislocation.

Septic arthritis

Diagnosis

The following tests can help to diagnose septic arthritis:

  • Joint fluid analysis. Infections can alter the color, consistency, volume and composition of fluid within the joints. A sample of this fluid can be withdrawn from your affected joint with a needle. Lab tests can determine which organism is the cause of your infection, so your doctor will know which medicines are prescribed.
  • Blood tests. These can determine if there are signs of infection in the blood. A sample of your blood is drawn from a vein with a needle.
  • Imaging tests.X-rays and other imaging tests of the affected joint can assess the damage to the joint or the detachment of an artificial joint. Specialized analysis that involves the ingestion or injection of a small amount of a radioactive chemical can be used if your doctor suspects that you have a prosthetic joint infection and it has been over a year since she underwent surgery.

Imaging tests. X-rays and other imaging tests of the affected joint can assess the damage to the joint or the detachment of an artificial joint.

Specialized analysis that involves the ingestion or injection of a small amount of a radioactive chemical can be used if your doctor suspects that you have a prosthetic joint infection and it has been over a year since she underwent surgery.

Treatment

Doctors rely on the joint drainage and antibiotics for the treatment of septic arthritis.

Drain assembly

The removal of the infected joint fluid is crucial. Drainage methods include:

  • The needle. In some cases, your doctor may remove the infected fluid with a needle that is inserted into the joint space.
  • Scope of application of the procedure. In the arthroscopy (ahr-THROS-kuh-pee), a flexible tube with a video camera on its tip is placed in your joint through a small incision. Suction and drainage tubes are inserted through small incisions around the joint.
  • The open surgery. Some joints, such as the hip, are more difficult to drain with a needle or arthroscopy, to open a surgical procedure may be needed.

Antibiotics

To select the most effective medication, the physician must identify the organism causing the infection. Antibiotics are usually given through a vein in your arm, in the first place. Later, you may be able to switch to oral antibiotics.

Treatment usually lasts two to six weeks. Antibiotics have a risk of side effects, such as nausea, vomiting, and diarrhea. Allergic reactions may also occur. Ask your doctor about what side effects you can expect from your medication.

The removal of the replacement of the joint

If an artificial joint is infected, the treatment often involves removal of the joint and replace it temporarily with a set spacer — a device made with antibiotic cement. Several months later, a new joint replacement implants.

If a joint replacement can't be removed, a doctor can clean the joint and remove damaged tissue, but keeping the artificial joint in place. Intravenous antibiotics followed by oral antibiotics for several months to prevent the reoccurrence of the infection.

Preparing for your appointment

If you have pain and inflammation in the joints, which is likely to start by seeing your family doctor. He or she may refer you to an orthopedic surgeon, a specialist in infectious diseases or joint specialist (rheumatologist).

Here's some information to help you prepare for your appointment.

What you can do

When you call to make the appointment, ask if you need to do anything in advance, such as fasting for certain tests. Make a list of:

  • Your symptoms, including any that may seem unrelated to the reason for which you scheduled the appointment
  • Key personal information, including to other medical conditions you may have, and the recent infections
  • The drugs, vitamins or supplements you are taking, including dose
  • Questions to ask your doctor

Have a friend or family member, if possible, to help you remember the information they give you.

For septic arthritis, questions to ask your doctor include:

  • What is likely causing my symptoms?
  • There are other possible causes?
  • What tests do I need?
  • Is my condition likely temporary or chronic?
  • What is the best course of action?
  • There are alternatives to the approach that you're suggesting?
  • How soon can I expect my symptoms improve with treatment?
  • What can I do in the meantime to help relieve my pain in the joints?
  • Am I at risk of long-term complications of this condition?
  • How can I best manage this condition with my other health problems?
  • You should see a specialist?
  • Are there brochures or other printed material that I can take? What sites do you recommend?

Do not hesitate to ask other questions.

What to expect from your doctor

Your doctor may ask you questions, such as:

  • When did your symptoms begin?
  • The symptoms been continuous or occasional?
  • How severe are the symptoms?
  • What, if anything, seems to improve your symptoms?
  • What, if anything, appears to worsen your symptoms?
  • Have you ever had joint surgery or joint replacement?
  • Do you use recreational drugs?
Symptoms and treatment of Septic arthritis