HomeHealth TopicsInfectionsInfectious Arthritis
Back to Infections
Infectious Arthritis
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Infections

Infectious Arthritis

Infectious arthritis is a joint infection that can cause intense pain, swelling, and fever, requiring prompt diagnosis and treatment.

Overview

Most kinds of arthritis cause pain and swelling in your joints. Joints are places where two bones meet, such as your elbow or knee. Infectious arthritis is an infection in the joint. The infection comes from a bacterial, viral, or fungal infection that spreads from another part of the body.

Symptoms

  • Intense pain in the joint
  • Joint redness and swelling
  • Chills and fever
  • Inability to move the area with the infected joint

Causes & Risk Factors

General infection

The joint becomes infected when bacteria, viruses, or fungi travel from another part of the body to the joint space.

Reactive arthritis

One type of infectious arthritis is reactive arthritis. The reaction is to an infection somewhere else in the body. The joint is usually the knee, ankle, or toe. Triggers can include:

  • An infection in the bladder or urethra
  • In women, an infection in the vagina
  • Bacteria passed on during sex (affecting both men and women)
  • Eating food or handling something that has bacteria on it

Diagnosis

To diagnose infectious arthritis, your health care provider may do tests of your blood, urine, and joint fluid.

Treatment & Management

Treatment includes medicines and sometimes surgery.

Frequently Asked Questions

Yes, it is possible to have infectious arthritis without a high fever, particularly in older adults, individuals with weakened immune systems, or those with specific types of infections like Lyme disease or fungal arthritis. While fever is a common sign of systemic infection, the absence of fever does not rule out a serious joint infection. If you experience severe joint pain, swelling, redness, and an inability to bear weight, seek medical attention immediately, as these local symptoms are often more reliable indicators of septic arthritis than temperature alone.
Treatment for bacterial infectious arthritis typically requires a combination of intravenous antibiotics for the first few days, followed by oral antibiotics for a total course of 2 to 6 weeks. You may start to feel less pain and swelling within 48 to 72 hours of starting effective antibiotics, but it is critical to complete the entire prescribed course to prevent the infection from returning or causing permanent joint damage. Stopping medication early because symptoms improve is a common cause of treatment failure.
Septic arthritis occurs when bacteria or other pathogens are physically present inside the joint space, causing direct infection and destruction of joint tissue. Reactive arthritis, on the other hand, is an immune-mediated response to an infection located elsewhere in the body, such as the gut or urinary tract. In reactive arthritis, the joint fluid is sterile (no bacteria are found in the joint), but the body's immune system mistakenly attacks the joint. Treatment differs significantly; septic arthritis requires aggressive antibiotics and often drainage, while reactive arthritis is managed with anti-inflammatory medications and treatment of the original trigger.
Surgery is not always necessary, but it is frequently required for severe cases. Simple needle aspiration (draining the joint with a needle) may be sufficient for smaller joints or early-stage infections. However, larger joints like the hip or knee, or cases where the infection is not responding to antibiotics and drainage, often require arthroscopic or open surgical debridement to thoroughly clean the joint space and remove infected tissue. The decision depends on the joint involved, the severity of the infection, and the patient's response to initial medical management.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

kontakt@hittavard.se

Ⓒ 2024. Alla rättigheter förbehålls av juxt ab

Sök
Om ossVillkor och policyVanliga frågorKontakta oss