Juvenile arthritis is divided into different subtypes, depending on the number of affected joints, the age of the patients, and possible accompanying conditions:

1. Oligoarticular JIA:
   • Affects up to four joints, often knees or ankles.
2. Polyarticular JIA (Rheumatoid factor positive or negative):
   • Affects five or more joints, similar to rheumatoid arthritis in adults.
3. Systemic JIA (Still's disease):
   • Accompanied by fever, skin rashes, and internal inflammations.
4. Enthesitis-related arthritis:
   • Causes inflammation at tendon attachments, often associated with spinal involvement.
5. Psoriatic arthritis:
   • Occurs along with psoriasis or psoriatic skin changes.

The exact cause of JIA is not yet fully understood, but genetic and environmental factors are discussed as triggers:

• Autoimmune reaction:
  • The immune system mistakenly attacks healthy tissue, leading to inflammation.
• Genetic predisposition:
  • Certain gene variants increase the risk of developing JIA.
• Infections:
  • Viruses or bacteria could act as triggers for the immune reaction.
• Environmental factors:
  • Exposure to pollutants or stress could promote the disease.

The symptoms vary depending on the subtype and severity of the disease, but often include:

- Joint pain:

- Pain that is worse in the morning and improves throughout the day.

- Swelling:

- Swelling in the affected joints, often visible and palpable.

- Movement restrictions:

- Limited mobility of the joints, especially after prolonged periods of rest.

- Fever and rash:

- In the systemic form, fever and characteristic rashes also occur.

- Eye problems:

- Uveitis (inflammation of the eyes) is a common accompanying symptom.

- Fatigue:

- Chronic fatigue and general weakness.

The diagnosis of JIA is complex and is based on a combination of medical history, clinical examination, and supplementary tests:

- Medical History:

- Collection of medical history, symptoms, and family predispositions.

- Clinical Examination:

- Checking for swelling, movement restrictions, and joint deformities.

- Laboratory Tests:

- Determination of inflammation markers such as CRP and ESR, as well as specific antibodies like rheumatoid factor or ANA (antinuclear antibodies).

- Imaging Techniques:

- X-ray: To assess joint changes or bone damage.

- MRI: Detailed depiction of soft tissue changes and inflammations.

- Ultrasound: To detect joint effusions and inflammations.

Conservative Therapy

The treatment aims to control inflammation, relieve pain, and preserve joint function:

• Medication Therapy:
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) for pain relief and anti-inflammation.
  • Disease-modifying antirheumatic drugs (DMARDs) like methotrexate to control the autoimmune reaction.
  • Biologics for targeted inhibition of specific inflammatory factors.
• Physiotherapy:
  • Exercises to improve joint mobility and strengthen muscles.
• Occupational Therapy:
  • Adjustment of daily activities to relieve joint stress.

Surgical Therapy

In severe cases or with advanced joint destruction, surgical interventions may be necessary:

• Synovectomy:
  • Removal of the inflamed joint lining.
• Joint Replacement:
  • Implantation of a prosthesis in cases of irreversible joint damage. 

Since the exact cause is not known, there are no specific preventive measures. However, the following general recommendations can help improve quality of life:

1. Early diagnosis: Consult a specialist early if joint complaints persist.
2. Regular exercise: Joint-friendly sports such as swimming or cycling promote mobility.
3. Relaxation exercises: Stress management to support the immune system.
4. Eye examinations: Regular check-ups by an ophthalmologist for early detection of uveitis.