How to Use the AGEP EuroSCAR Score

This tool applies the EuroSCAR validation score for Acute Generalized Exanthematous Pustulosis (AGEP).¹ By combining key clinical features, timing and systemic findings, and histopathology, it generates a total score categorized as no, possible, probable, or definite AGEP. This calculator is provided for educational purposes only; I cannot guarantee that it is free of errors, and clinicians should always refer to the original EuroSCAR publication and apply clinical judgment when using this tool in real-world practice.

1. Morphology

Assess three independent features at presentation: pustules, erythema, and distribution. Score each separately as Typical, Compatible, or Insufficient.

Pustules
Typical (+2): Numerous small (<5 mm), non-follicular, superficial pustules on edematous erythema, with sudden onset and possible confluence.
Compatible (+1): Pustules present but not classic (e.g., fewer, larger, partially follicular, or limited extent).
Insufficient (0): Pustules absent, very sparse, obscured, or not assessable.

Erythema
Typical (+2): Diffuse, bright red, edematous erythema clearly associated with pustules.
Compatible (+1): Erythema present but less intense, patchy, or atypical.
Insufficient (0): Minimal, absent, or poorly documented erythema.

Distribution / pattern
Typical (+2): Generalized, symmetric eruption, often starting on face, intertriginous areas, or trunk, with rapid spread.
Compatible (+1): Suggestive distribution but limited extent or atypical initial site.
Insufficient (0): Distribution unclear, localized only, or undocumented.

2. Post-pustular Desquamation

Yes (+1): Characteristic superficial peeling after pustule resolution.
No / insufficient (0): No desquamation observed or follow-up insufficient.

3. Course and Systemic Features

Mucosal involvement — Yes (−2): Clinically relevant oral, ocular, or genital lesions; No (0): Absent.
Acute onset ≤ 10 days — Yes (0): Eruption begins within 10 days of the suspected trigger; No (−2): Latency >10 days.
Resolution ≤ 15 days — Yes (0): Clinical resolution within 15 days; No (−4): Persistent beyond 15 days.
Fever ≥ 38.0 °C — Yes (+1): Documented fever at or near onset; No (0).
Neutrophilia — Yes (+1): Neutrophils ≥ 7,000 / mm³; No (0).

4. Histology (if biopsy performed)

Select the single best overall interpretation.

Other disease (−10): Histology clearly supports an alternative diagnosis (e.g., pustular psoriasis, infection, SJS/TEN).
Not done / not representative (0): No biopsy or inadequate sample.
Neutrophil exocytosis (+1): Neutrophils migrating into epidermis without well-formed pustules.
Compatible pustules (+2): Subcorneal or intra-epidermal pustules compatible with AGEP but not classic; papillary dermal edema may be absent.
Classic AGEP pattern (+3): Spongiform subcorneal and/or intra-epidermal pustules with papillary dermal edema, often with mixed perivascular infiltrate.

About This Tool

I was inspired to build this tool when I couldn’t find one by googling. I was tired of calculating this by hand. I expect this page will be obsolete if it ever gets added to MDCalc.

1. Tetart F, Walsh S, Milpied B, et al. Acute generalized exanthematous pustulosis: European expert consensus for diagnosis and management. J Eur Acad Dermatol Venereol. 2024;38(11):2073-2081. doi:10.1111/jdv.20232 ↩︎