Calculators & Tools

Behçet Disease — ISG Criteria

International Study Group criteria: recurrent oral ulceration is MANDATORY plus ≥2 other features.

1 What is the Behçet Disease — ISG Criteria?

The Behçet Disease — ISG Criteria is a rheumatology scoring tool used in paediatric practice. International Study Group criteria: recurrent oral ulceration is MANDATORY plus ≥2 other features. It scores 5 criteria and interprets the total across 3 bands, so the number always arrives with the severity it implies rather than on its own. In PediAid each criterion is shown as a labelled option with the weight it carries, so the total can be checked rather than taken on trust.

2 When to use it

  • Grading severity at the bedside in rheumatology
  • Recording an objective severity band in the case notes
  • Deciding when a total crosses the threshold for escalation
  • Re-scoring to track whether a child is improving or deteriorating
  • Checking the exact criteria of a score used infrequently

3 Formula & method

The score sums 5 criteria: MANDATORY - Recurrent oral ulceration ≥ 3 times in 12 months; Recurrent genital ulceration or scarring; Eye lesions - anterior/posterior uveitis, cells in vitreous, or retinal vasculitis; Skin lesions - erythema nodosum, pseudofolliculitis, papulopustular lesions, acneiform nodules; Positive pathergy test read at 24-48 hours. Totals are then banded: any score - Criteria not met: recurrent oral ulceration is mandatory - without it, Behçet disease cannot be classified by ISG criteria; 4 criteria or more - Oral ulcers only: mandatory oral ulceration present, but ≥2 additional features are required to classify; 6 criteria or more - Criteria MET: recurrent oral ulceration plus ≥2 additional criteria - classifies as Behçet disease. Assess for ocular, neurological and vascular involvement.
  • Paediatric-specific PEDBD criteria also exist and may perform better in children.
  • Source: International Study Group for Behçet's Disease. Criteria for diagnosis of Behçet's disease. Lancet 1990;335:1078-80.

4 Frequently asked questions

How many criteria does the Behçet Disease — ISG Criteria use?

5. They are MANDATORY - Recurrent oral ulceration ≥ 3 times in 12 months; Recurrent genital ulceration or scarring; Eye lesions - anterior/posterior uveitis, cells in vitreous, or retinal vasculitis; Skin lesions - erythema nodosum, pseudofolliculitis, papulopustular lesions, acneiform nodules; Positive pathergy test read at 24-48 hours.

What do the bands of the Behçet Disease — ISG Criteria mean?

The total is interpreted as: any score - Criteria not met: recurrent oral ulceration is mandatory - without it, Behçet disease cannot be classified by ISG criteria; 4 criteria or more - Oral ulcers only: mandatory oral ulceration present, but ≥2 additional features are required to classify; 6 criteria or more - Criteria MET: recurrent oral ulceration plus ≥2 additional criteria - classifies as Behçet disease. Assess for ocular, neurological and vascular involvement.

Does the score replace clinical judgement?

No. It is a structured way to record and communicate severity. A clinician concerned about a child should act on that concern regardless of the total.

Where does this score come from?

Paediatric-specific PEDBD criteria also exist and may perform better in children.

Does it work offline?

Yes. Score definitions are bundled with the PediAid app, so the score computes without a connection.

For qualified clinicians. This page and the PediAid app are a clinical aid only. Calculations and reference data must be verified against the patient's clinical context, the source guideline and your local protocols before any treatment decision is made.