Medical expert of the article
New publications
Swollen and hot joints
Last reviewed: 04.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
The term "arthritis" means inflammation of one or more joints. Signs of inflammation include pain, swelling, redness of the skin over the inflamed joint, its stiffness; the inflamed joint is hot to the touch (+ general increase in body temperature). When establishing a diagnosis, it is necessary to resolve the following key questions.
- Is only one joint affected (i.e. is it monoarthritis)?
- Is the patient otherwise healthy or does he/she have another disease that causes arthritis (eg, ulcerative colitis), or are there risk factors for the development of an infectious process (diabetes mellitus, renal failure, immunosuppression, parenteral drug administration)?
- Why is the joint swollen? What is in the joint cavity: blood, crystals, pus?
In such situations, it is always necessary to perform a diagnostic aspiration puncture of the joint cavity.
The presence of rheumatoid factor in the blood divides all arthritis into seropositive (SP) and seronegative.
Causes of Swollen and Hot Joints
Monoarthritis
- Bacterial infection such as tuberculosis, gonorrhea, septicemia
- Gout or pseudogout
- Reiter's disease
- Traumatic hemarthrosis
- Psoriasis
- Rheumatoid arthritis
- Growth of leukemic cells inside the joint
Polyarthritis
- Many viruses - measles, rubella, mumps, hepatitis A, Epstein-Barr virus
- Rheumatoid arthritis
- Sherrens syndrome
- Acute rheumatism
- Systemic lupus erythematosus
- Non-specific ulcerative colitis, Crohn's disease
- Manifestation of drug-induced disease
Examination of the patient
- Fluid aspirated from the joint cavity is examined under a microscope, cultured, smeared for Gram staining, and examined for crystal content in compensated polarized light. Synovial fluid may be blood-stained in pseudogout, after joint trauma, but this is rare in septic arthritis.
- An X-ray of the affected joint should be taken. It is important to find out if there are any signs of trauma (fractures) or signs of rheumatoid arthritis. Calcification of the cartilage indicates pseudogout. In some patients, the X-ray of the affected joint is normal.
- Clinical blood test, ESR, blood uric acid levels, rheumatoid factor (RF), C-reactive protein (normally less than 20 mg/l) - all these indicators can be pathologically changed in both seropositive and seronegative arthritis and, of course, are not a screening test for sepsis.
How to examine?
Who to contact?
Treatment measures
Until the results of microbiological examination of synovial fluid are obtained, all persons with acute monoarthritis should be referred to hospital, since it is absolutely necessary to exclude an infectious course of the disease or prescribe an antibiotic adequate to the specific infection.
Treatment is determined individually in each specific case. If septic arthritis is diagnosed, it is advisable to perform joint lavage (it is good to find a specialist in such cases, since if the hip joint is affected, surgical intervention may be required), the patient is prescribed flucloxacillin (it is also active against staphylococci), until the sensitivity of the microflora to antibiotics is established. The drug is administered 500 mg intravenously slowly every 6 hours. Patients aged 2 to 10 years are given 1/2 of this dose. In infants, the infectious agent is often Haemophilus. Treatment is continued for 6 weeks.