Comparison of Three Diagnostic Frameworks for Pyoderma Gangrenosum

Area of Science:

• Dermatology
• Clinical Research
• Inflammatory Diseases

Background:

• Pyoderma gangrenosum (PG) is a chronic inflammatory skin condition causing ulcerations.
• Existing diagnostic frameworks (Su, PARACELSUS, Delphi) lack consensus and validation.
• Accurate diagnosis is crucial for effective treatment and clinical trial patient selection.

Purpose of the Study:

• To evaluate and compare the concordance of three proposed PG diagnostic frameworks.
• To assess the performance of Su, PARACELSUS, and Delphi criteria in a defined patient cohort.
• To identify the most reliable diagnostic framework for pyoderma gangrenosum.

Main Methods:

• Retrospective cohort study of 47 patients with confirmed pyoderma gangrenosum.
• Evaluation of diagnostic framework concordance using clinical data, photographs, and pathology.
• Statistical analysis including multirater agreement and chance-adjusted agreement (Fleiss' kappa).

Main Results:

• The PARACELSUS score identified the highest proportion of PG patients (89%).
• Delphi and Su criteria each identified 74% of PG patients.
• Overall agreement among the three frameworks was 72%, with a chance-adjusted agreement of 0.44.

Conclusions:

• The PARACELSUS framework demonstrates superior performance in identifying pyoderma gangrenosum patients.
• Current diagnostic frameworks show moderate agreement, highlighting the need for refinement.
• Future research should focus on improving diagnostic accuracy to minimize misdiagnosis and misclassification in trials.