Enthesitis-related juvenile idiopathic arthritis

What it is

From: Orphanet

A rare inflammatory rheumatic disease in a child younger than 16 years characterized by arthritis and/or enthesitis and/or acute anterior uveitis. The most commonly affected joints at diagnosis are the knees, ankles, and hips. The small joints of the feet and toes are also often involved.

Reported clinical features and what the terms mean

The following findings are associated with this condition in Orphanet. They are not a checklist for diagnosing yourself, and they do not all occur in every affected person. Some are examination, imaging or laboratory findings that cannot be recognised at home.

The frequency labels describe how often a finding was reported among people with the condition in the source. They do not give the chance that a person with that symptom has the condition. Definitions below reproduce HPO terminology; they explain the term, not the likely severity in an individual.

Arthralgia · Very frequent (99-80%)

Joint pain.

Arthritis · Very frequent (99-80%)

Inflammation of a joint.

Enthesitis · Very frequent (99-80%)

Abnormal lumbar spine morphology · Frequent (79-30%)

Any structural abnormality of the lumbar vertebral column.

Abnormality of the ankles · Frequent (79-30%)

An anomaly of the joint that connects the foot with the leg.

Abnormality of the calcaneus · Frequent (79-30%)

An abnormality of the calcaneus, also known as the heel bone, one of the or heel bone, one of the components of the tarsus of the foot which make up the heel.

Abnormality of the fascia · Frequent (79-30%)

An abnormality of fascia.

Abnormality of the hip joint · Frequent (79-30%)

An abnormality of the hip joint.

Abnormality of the vertebral column · Frequent (79-30%)

Any abnormality of the vertebral column.

Back pain · Frequent (79-30%)

An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) localized to the back.

Oligoarthritis · Frequent (79-30%)

A type of arthritis that affects up to four joints in the first six months of disease.

Sacroiliac arthritis · Frequent (79-30%)

Inflammation of the sacroiliac joint, generally accompanied by lower back pain.

Thickened Achilles tendon · Frequent (79-30%)

An abnormal thickening of the Achilles tendon.

Hip osteoarthritis · Frequent (79-30%)

Other findings in the same source

From: Orphanet

Additional reported features include Knee osteoarthritis (Frequent (79-30%)); Abnormal foot morphology (Occasional (29-5%)); Abnormal heart morphology (Occasional (29-5%)); Abnormal metatarsal morphology (Occasional (29-5%)); Abnormality of metacarpophalangeal joint (Occasional (29-5%)); Abnormality of skeletal morphology (Occasional (29-5%)); Abnormality of the cervical spine (Occasional (29-5%)); Abnormality of the elbow (Occasional (29-5%)); Abnormality of the shoulder (Occasional (29-5%)); Abnormality of the thoracic spine (Occasional (29-5%)). This is a selected summary, not a complete description of the condition.

When it may begin

From: Orphanet

Adolescent; Childhood

Inheritance in the source

From: Orphanet

Unknown

Which doctor should you see?

The suggested department for discussing Enthesitis-related juvenile idiopathic arthritis is Rheumatology, with a rheumatologist as the relevant type of clinician. General physician / Family Medicine; paediatrician for children. Referral depends on symptoms.

This is an editorial referral starting point. The appropriate clinic depends on the person’s age, symptoms, previous diagnosis and local services. The first clinician can decide whether another specialty or a team is needed; a department label does not confirm the diagnosis.

How to prepare for an assessment

Bring a short timeline of the main symptoms: when they first appeared, whether they are constant or episodic, what seems to change them, and how they affect daily activities. Include previous reports, discharge summaries, current medicines and supplements, allergies, and any relevant family history. A dated record is more useful than trying to match every feature in an online article.

Ask the clinician what is already established and what remains uncertain. If a test is suggested, ask what question it answers, what its limitations are and how the result would change the next step. The information here is not an instruction to arrange every possible test. In children, bring growth, developmental and school information if it is relevant to the concern.

• Are the findings inflammatory, structural or due to another mechanism?
• Is there evidence that other organs need assessment?
• How will function and any treatment-related risks be monitored?

Treatment discussions and follow-up

The material gathered for this draft does not provide a complete condition-specific treatment pathway for Enthesitis-related juvenile idiopathic arthritis. That gap does not mean that treatment is unavailable. A clinician needs to establish the diagnosis and review current guidance before recommending medicines, procedures, rehabilitation or other support.

Before leaving the appointment, clarify the next review date, who will communicate results, and whom to contact if the situation changes. Discuss difficulties with sleep, work, school, mobility, eating or emotional wellbeing when these are relevant. Practical support may require coordination between the treating clinician and other services.

The collected references do not establish a complete prevention or long-term outlook section for this entry. Missing information should not be interpreted as proof that prevention is impossible or that a particular outcome is inevitable. Ask what is known for the exact subtype, stage and personal circumstances, and which uncertainties remain.

When to seek emergency help

Severe breathing difficulty, collapse, new stroke-like symptoms, a seizure that is prolonged or repeated without recovery, uncontrolled major bleeding, or an immediate risk of self-harm require emergency help. In India, call 112 or reach the nearest emergency department. This is a general, non-exhaustive warning list; it is not a condition-specific triage tool.