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Basics of infectious arthritis
Infectious arthritis is a form of arthritis that is produced by an infection. It is also called "septic arthritis."
An infection is an illness that is caused by certain types of germs. There are three major kinds of germs that can cause infections: bacteria viruses or fungi.
Normally these germs are not found in a person's body. They can live in the air in uncooked food plants soil animals or trash. When they enter a person's body these germs generally cause the person to become sick. Doctors call an illness that is directly caused by any one of these germs an "infection."
Arthritis means joint inflammation ("arthr-" = joint"; "-itis" = inflammation). There are over 100 kinds of arthritis. How does a person know if he or she has inflammation in a joint or another part of the body? Generally that area becomes warm painful swollen red and/or stiff.
Unlike other types of arthritis infectious arthritis is usually not a long-term illness. Treated promptly and properly it is generally a curable form of arthritis. However without proper treatment infectious arthritis can result in serious damage to the joints involved and may spread to other parts of the body. That's why it is important to recognize the symptoms of infectious arthritis and get prompt treatment.
Anyone can get infectious arthritis but some people are more likely to get it than others.
These are people who have other diseases or whose bodies are not as strong at fighting off infections. This includes people who have: diabetes sickle cell anemia severe kidney disease immune deficiency some forms of cancer abnormal heart valve or drug or alcohol abuse problems. Infants and elderly people also have more difficulty fighting certain infections.
People who have auto immune deficiency syndrome (AIDS) may develop a severe form of Reiter's syndrome. One symptom of this syndrome is pain and inflammation in one or more joints. Children who have strep throat are particularly at risk for getting rheumatic fever if not treated promptly with antibiotics. In addition to other symptoms rheumatic fever may involve joint pain in many joints. People who have some other form of arthritis are more likely to get infectious arthritis. This is because germs are more likely to invade damaged joints rather than healthy ones.
People who have surgery to replace a damaged joint have about a 1% chance of getting infectious arthritis. Most of these infections generally occur within a few days to months after surgery but infection can also appear several years later. People having joint replacement surgery should alert their doctor if symptoms such as fever or persistent joint pain occur.
Certain drugs can make it more likely for people to get infectious arthritis. Corticosteroids such as prednisone affect a person's resistance. People who receive repeated injections of corticosteroids into the same joint have an increased risk of getting infectious arthritis. are treated with agents such as azathioprine methotrexate and cyclophosphamide. These medications can decrease a person's ability to resist infections.
If people with rheumatoid arthritis get infectious arthritis they might think the symptoms are a "flare-up." That is why it is important to tell one's doctor about any sudden pain swelling warmth or redness that occurs--particularly if it occurs in only one joint.
Certain jobs can expose workers to disease-producing germs. For example people who work with animals plants soil or marine life such as farmers gardeners or fishermen may be more likely to get infectious arthritis. This is because the animals and materials they work with can carry the infectious germs.
One person cannot get infectious arthritis from someone else who has it. In other words it is not contagious (spread from one person to another). However certain infections for example measles and gonorrhea can be spread from one person to another and then produce infectious arthritis.
AnatomyInfectious arthritis may occur without any other infection present. However it is usually the result of a previous infection. That is a germ first causes an infection elsewhere in the body then spreads to one or more joints to produce infectious arthritis.
A germ can enter through almost any place in a person's body. The most common places of entry are a person's skin throat ears or nose. Once inside the body the germs can get into the blood stream. From there they can travel to the person's joints (or any place that is suitable for them to live). Sometimes a bacterium virus or fungus can enter a person's joint directly through a wound.
Most often only one joint is affected. Sometimes two or three joints become involved. The large joints are most often infected especially the shoulders hips and knees although other joints can also become involved.
Sometimes a condition called erythema nodosum can occur along with an infection. Although it is most often associated with tuberculosis and infections by certain fungi it is not due directly to these infectious germs.
SymptomsThe most noticeable symptom of erythema nodosum is red tender bumps about the size of a quarter--in the skin of the lower legs and sometimes on other parts of the body. Other symptoms that may appear include inflammation of the ankle (and sometimes other joints) and fever.
Infectious arthritis may be caused by bacteria viruses or fungi.
Most types of infectious arthritis are caused by bacteria. There are many different kinds of bacteria that produce a variety of infections. Bacteria that can cause infectious arthritis include: gonococcus certain Gram-positive bacteria certain Gram-negative bacteria spirochetes and tuberculosis. Descriptions of these bacteria and the symptoms they produce are listed below.
Gonococcus is the name of the bacterium that causes gonorrhea. Gonorrhea is a sexually transmitted disease. It primarily affects the genital area. However the gonococcus bacterium can travel through the blood stream to other parts of the body. If it settles in one or more joints infectious arthritis can develop in those joints and the area that surrounds the joints. Gonococcus generally affects the knee joints and can also affect the tendons and bursae to cause tendonitis and bursitis.
This infectious arthritis can occur within days or weeks after the symptoms of gonorrhea appear. It occurs more often in women than in men. The symptoms of gonorrhea are not as obvious for women. Therefore women generally seek treatment later than men. This delay in treatment gives the bacteria more time to travel through the bloodstream.
Symptoms of infectious arthritis caused by gonococcus may include:
This type of arthritis should be treated immediately--as soon as you notice symptoms--to prevent serious damage to the joints.
Gonorrhea is spread from person to person by sexual contact. Therefore care should be taken in sexual relationships where there may be a chance of getting the disease. The spread of gonorrhea can usually be prevented by the correct use of condoms. Anyone who thinks he or she may have gonorrhea should see a doctor as soon as possible. Appropriate treatment with antibiotics can prevent damage to joints and other parts of the body.
There are several different kinds of Gram-positive bacteria. They are called Gram-positive because when mixed in the laboratory with a solution called "Gram's stain they take on a bluish-purple stain or color. Some of the Gram-positive bacteria that can cause infectious arthritis are: staphylococcus, streptococcus, and pneumococcus.
These Gram-positive bacteria cause other illnesses such as meningitis, pneumonia, or an abscess. Often people with these illnesses develop infectious arthritis when the bacteria spread to a joint and produce inflammation. In other cases, Gram-positive bacteria cause infectious arthritis, but no other illness is detected.
Staphylococcus is the second most common cause of infectious arthritis. It is often called a staph infection." A staph infection can occur as a result of a skin or sinus infection or after surgery. People who have rheumatoid arthritis or who take steroids or immunosuppressive agents (such as imuran cytoxan and methotrexate) are more apt to get infectious arthritis from staphylococcus bacteria.
Symptoms of a "staph infection" in a joint may include:
These bacteria are called Gram-negative because they do not take on a bluish-purple color when mixed with the Gram's stain. They are less likely to produce infectious arthritis than Gram-positive bacteria. Gram-negative bacteria commonly infect people whose bacteria-fighting defense system (immune system) is already weak.
Hemophilus is a Gram-negative bacterium that causes severe sore throat and meningitis. It is a major cause of infectious arthritis in infants but rarely causes it in adults.
Spirochete- Lyme Disease
Spirochetes are bacteria that appear spiral shaped under a microscope. There are many different kinds of spirochetes. One kind (called Borrelia) causes a form of infectious arthritis called Lyme disease. This disease occurs in people as a result of a tick bite. Anyone can get Lyme disease but it is more common in children.
The Borrelia spirochete is carried by a small tick (called Ixodes) that lives on deer and mice. It is found in wooded areas during the spring and early summer. Many areas of the country have reported cases of Lyme disease. However most cases occur in seven states: New York New Jersey Rhode Island Connecticut Massachusetts Wisconsin and Minnesota.
People infected may not have seen the tick because it is very tiny. It is oval has eight legs and is often no larger than a pinhead or match head.
When the tick bites someone it injects the spirochete into the person's blood stream. Symptoms of the infection usually do not appear until 1-3 weeks after the bite.
You may want to protect yourself and others from Lyme disease when you visit wooded or lake areas as suggested below.
The following measures may help prevent tick bites:
Symptoms of early Lyme disease include:
If untreated the spirochete may spread to the person's brain heart and nervous system. This could lead to symptoms such as:
With proper medication Lyme disease usually goes away in a short time. However if not diagnosed and treated properly symptoms can become more severe and recur several times over a year or more.
The bacterium that causes tuberculosis can also cause infectious arthritis. It is much less common today than it was years ago. When it does occur it is often very slow to develop and usually spreads from the lung to involve only one joint.
Infectious arthritis can also be caused by viruses. It is usually produced by a viral infection that is already present in a person's body. Infectious hepatitis mumps and infectious mononucleosis are viral infections that can lead to a short bout of infectious arthritis. Generally the joint inflammation lasts no more than one to two weeks. German measles can also produce an infectious arthritis which may occasionally last as long as one year after the measles rash is gone.
Fungi are the least common cause of infectious arthritis. Arthritis produced by a fungus usually develops very slowly. Types of fungi that can produce arthritis are usually found in soil bird droppings and certain plants (especially roses). Chicken farmers and gardeners are especially likely to be exposed to this type of arthritis.
Bacterial viral and fungal infections are different from each other in the following ways:
Can periodontal surgery cause infectious arthritis?Any significant manipulation of the gums can cause bacteria to enter the blood stream--even brushing the teeth in the presence of gum disease. Periodontal health is important. In rare cases periodontal disease may cause an infectious arthritis especially when extensive dental work is being done. We worry about it in particular for those with artificial joints in place as they can not combat the bacterial that might get into the blood stream. Infectious arthritis occurs more frequently in people with abnormal joints especially rheumatoid arthritis people with artificial joints or those with diabetes. For those with arthritis or artificial joints in place consult your rheumatogist or orthopedist before having dental work done. An antibiotic 1 hour before and 8 hours after may be in order.
To determine if a person has infectious arthritis the doctor will first ask about the person's symptoms and any other medical conditions.
The doctor will want to know about any recent travel illness or contact with people who have had infections. Work or home conditions might also give the doctor clues about the illness.
After the medical history the doctor will do a physical exam and order special tests. X-rays may be taken to determine if there is joint damage. Various laboratory tests can be done to find out if an infection is present.
It is most important to identify the specific germ causing the infection. Bacteria and fungi can usually be identified from joint fluid blood urine or the infected area. The doctor will almost always want to remove and examine fluid from the infected joint. If tuberculosis or fungi are suspected it will be necessary to remove a tiny piece of tissue from the joint. This is called a biopsy. In the laboratory the fluid or tissue will be examined under the microscope to determine what kind of bacteria or fungi are present.
A viral infection is usually diagnosed by a person's symptoms and medical history. After the infection has been present for weeks or longer blood tests may show the presence and amount of a person's own virus-fighting proteins (antibodies) in response to a viral infection.
Most often people with infectious arthritis need to go into the hospital for diagnosis and treatment; the treatment and length of stay will vary depending on the type of infectious arthritis present.
Treating bacterial infections
Almost all people whose infectious arthritis is caused by bacteria are given an antibiotic. Antibiotics are medications that fight off bacteria. Different antibiotics destroy different bacteria. Therefore the antibiotic prescribed depends on the type of bacteria present.
Antibiotics can be taken by mouth or given through the person's vein. When given through a vein it is called an intravenous or IV injection. An IV releases the antibiotic directly into the bloodstream. This allows the infection-fighting drug to travel faster in higher concentration and directly to the infected joint.
Often antibiotics can destroy an infection in a few days or weeks. In some cases antibiotics must be taken over several months. Remember to take antibiotics for the number of days prescribed--even if symptoms disappear. Many people think they can stop taking the medication when the symptoms are gone. Even though symptoms disappear bacteria may still be present. If not destroyed by the antibiotic the bacteria can re-infect the area.
Treating viral infections
Generally infectious arthritis caused by a virus goes away by itself. Medications are not available to treat viral infections. Resting in bed and drinking plenty of liquids are usually recommended.
Treating fungal infections
Fungal infections are often difficult to treat. Doctors can prescribe a fungus-fighting medication. This may need to be used for months. Surgery is sometimes performed to clean out the infected joint. Fungal infections are difficult to eliminate entirely. Even after successful treatment they may recur.
In many cases the doctor may need to drain one or more joints. This is done by inserting a needle into the joint and withdrawing fluid. This procedure is generally easy and usually not painful. It is done to remove any harmful substances released by the bacteria or by the body's bacteria fighting cells. Joint fluid drainage may need to be done several times. Most of the time repeated drainage along with high doses of IV antibiotics can prevent the need for surgery.
Arthritis treatment may also include resting and protecting the joints. Splints can be used to limit movement. This helps reduce pain and tissue damage.
After the infection is gone the doctor will frequently recommend exercises to build up muscle strength. Other exercises may be recommended to increase the joint's range of motion. A physical therapist can demonstrate and assist with exercises that can be done at home.
Summary of infectious arthritis
Infectious arthritis is a form of arthritis that is caused by bacteria viruses or fungi.
Many different types of infections can produce joint inflammation. This type of arthritis is almost always curable.
If the infection is diagnosed and treated promptly there is usually no lasting joint damage. If the infection is not treated early permanent joint damage may result. Bacterial and fungal infections are usually treated with medication. A viral infection will generally go away on its own.
Most often people with infectious arthritis are able to resume their normal activities once the infection is gone.
Some of this material may also be available in an Arthritis Foundation brochure. Contact the Washington/Alaska Chapter Helpline: (800) 542-0295. If dialing from outside of WA and AK contact the National Helpline: (800) 283-7800.
Adapted from the pamphlet originally prepared for the Arthritis Foundation by Frank R. Schmid MD. This material is protected by copyright.