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The utility of biopsy in pyoderma gangrenosum: a retrospective cohort study
Angel M Moore1, Jamie L Karch2, Katherine E Bradley1
1Dartmouth College, Geisel School of Medicine, Hanover, NH, USA.
Background:
Pyoderma gangrenosum (PG) is a rare skin condition characterized by chronic, painful ulcerations. It is considered a diagnosis of exclusion, often resulting in diagnostic delay. Histological results in PG, even when biopsied despite a risk of pathergy, are nonspecific.
Objectives:
To examine retrospectively the utility of biopsies in the diagnosis of 58 patients treated for PG.
Methods:
Medical records were reviewed to compare biopsy results versus the efficacy of diagnostic rating systems (Delphi, Su, PARACELSUS).
Results:
Among 58 patients, 26 (45%) underwent biopsies, with only 10 (38%) contributing to a PG diagnosis. As a single-centre and retrospective study, documentation style and sample size limit generalizability.
Conclusions:
Given risk of pathergy, nonspecific histopathological findings and low sensitivity, in our opinion, based on this small sample size, biopsies have limited diagnostic value for PG.
Insights
Biopsies offer limited diagnostic value for pyoderma gangrenosum (PG), a rare skin condition. Histological findings are nonspecific, and diagnostic rating systems may be more effective for PG diagnosis.
Area of Science:
- Dermatology
- Pathology
Background:
- Pyoderma gangrenosum (PG) is a rare, chronic skin condition causing painful ulcerations.
- It is a diagnosis of exclusion, frequently leading to delayed diagnosis.
- Histological findings in PG are nonspecific, even with biopsies taken despite pathergy risk.
Purpose of the Study:
- To retrospectively evaluate the diagnostic utility of biopsies in 58 patients treated for PG.
- To compare biopsy results with the effectiveness of established diagnostic rating systems.
Main Methods:
- Retrospective review of medical records for 58 patients diagnosed with PG.
- Comparison of biopsy results against diagnostic rating systems (Delphi, Su, PARACELSUS).
Main Results:
- Only 26 (45%) of patients underwent biopsies, with just 10 (38%) yielding results that supported a PG diagnosis.
- The study's retrospective, single-center nature and limited sample size restrict generalizability.
Conclusions:
- Biopsies demonstrate limited diagnostic value for pyoderma gangrenosum due to nonspecific histopathology and low sensitivity.
- Considering the risk of pathergy and nonspecific findings, diagnostic rating systems may offer greater utility in PG diagnosis.
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