Septic arthritis and gout are two types of arthritis that can cause similar symptoms. Both are painful, but one of them is a medical emergency.

Arthritis is a group of conditions that cause joint pain and inflammation. Septic arthritis is caused by an infection inside one or more of your joints. Gout is caused by the buildup of interjoint crystals.

Gout is estimated to affect about 3.9% of adults, or about 9.2 million people, in the United States. It most often develops in your big toe due to the buildup of a substance called uric acid. Symptoms generally flare for 1–2 weeks at a time.

Septic arthritis is also called infectious arthritis. It affects about 2–6 people per 100,000 people per year. It mostly occurs in children 2–3 years old and adults older than 80 years of age. It can be caused by bacteria, viruses, or other microorganisms that enter your joints.

In rare cases, gout can cause inflammation in your joint that mimics septic arthritis but without signs of infection. This complication is called pseudoseptic arthritis.

Keep reading to learn more about the differences between septic arthritis and gout.

Medical emergency

Septic arthritis is a very serious condition, with a 7–15% in-hospital death rate. More than a third of people have permanent joint complications.

Call emergency medical services or go to the nearest emergency room if you develop sudden and intense joint pain with a fever or feeling of general unwellness.

Here’s a look at how septic arthritis and gout symptoms compare.

Septic arthritis symptoms

Septic arthritis usually affects one joint. Your hips, knees, and ankles are most affected. Symptoms usually develop over a few days and require immediate attention.

Fever occurs in roughly half of people with septic arthritis. You may also develop chills or a general feeling of unwellness.

Joint symptoms can include joint:

Gout symptoms

Gout flare ups usually last for 1–2 weeks if they aren’t treated. Your big toe is the most affected joint followed by your:

  • other toes
  • ankles
  • knees
  • fingers

The most common symptoms are:

  • joint pain
  • tenderness or heat in your joint
  • swelling
  • red, shiny skin

Gout symptoms typically begin rapidly over a few hours.

Here’s a look at the underlying causes of septic arthritis and gout.

Septic arthritis causes

Septic arthritis develops when bacteria or other microorganisms enter a joint. Bacteria, viruses, or other microorganisms can trigger septic arthritis.

Septic arthritis might develop after:

  • a penetrating injury to your joint
  • joint surgery or injections
  • the spread of microorganisms to your joint through your blood

Pseudoseptic arthritis is a rare complication of gout. Pseudoseptic arthritis mimics septic arthritis without signs of infection.

Gout causes

Gout is caused by a condition called hyperuricemia, the buildup of a substance called uric acid. This substance comes from the breakdown of purines found in foods, such as:

  • red meat
  • organ meats
  • seafood
  • beans

Septic arthritis is a medical emergency that requires immediate medical attention.

It’s recommended you see a doctor or healthcare professional if you develop gout symptoms but haven’t received a diagnosis, especially if your pain is getting worse or if you have a fever.

Also see a doctor if you’ve received a diagnosis of gout but your medications aren’t effective at reducing your symptoms within a couple of days of a flare up.

According to the Centers for Disease Control and Prevention (CDC), gout can only be diagnosed during a flare up.

Doctors make a diagnosis with tests like:

  • assessing your symptoms
  • a physical examination
  • considering your personal and family medical histories
  • X-rays to examine your joints
  • blood tests

A test called arthrocentesis is often used to diagnose septic arthritis. This test involves extracting a sample of the fluid inside your joint with a long needle for lab testing.

Imaging tests like magnetic resonance imaging (MRI) or X-rays can help evaluate the extent of the damage in your knee.

Here’s a look at how gout and septic arthritis are treated.

Septic arthritis treatment

Septic arthritis requires immediate medical attention. Most people have to stay in a hospital for about 2 weeks.

Treatment options include:

  • intravenous (IV) antibiotics
  • fluid drainage from your joint
  • antibiotic tablets

Gout treatment

Gout can be treated with:

You can potentially prevent septic arthritis by avoiding activities that put you at risk of puncture wounds to your skin and treating infections like urinary tract infections promptly to make sure they don’t spread.

You may be able to prevent gout flare ups by reducing your intake of purines in your diet. Other preventive steps you could take include:

  • losing weight if you have overweight
  • limiting alcohol
  • drinking plenty of fluids

Here are some frequently asked questions people have about gout and septic arthritis.

Can gout be mistaken for septic arthritis?

Gout can cause similar symptoms as septic arthritis. It’s important to get a proper diagnosis to rule out septic arthritis or other forms of arthritis.

How can you tell the difference between septic arthritis and gout?

Gout and septic arthritis can cause similar symptoms. Septic arthritis often, but not always, causes a fever and a general feeling of unwellness.

Septic arthritis is triggered by microorganisms that enter your joints. It’s a medical emergency that needs immediate emergency attention.

Gout is caused by the buildup of a substance in your body caused by uric acid that leads to the formation of crystals in your joint. Gout most often develops in your big toe.