Pyoderma gangrenosum associated with granulomatosis with polyangiitis: a case report

Area of Science:

• Immunology
• Dermatology
• Rheumatology

Background:

• Pyoderma gangrenosum is a neutrophilic dermatosis with unclear pathogenesis.
• The co-occurrence of pyoderma gangrenosum and granulomatosis with polyangiitis is infrequently documented.
• This report details a case of pyoderma gangrenosum in a patient with granulomatosis with polyangiitis.

Purpose of the Study:

• To present a rare case of pyoderma gangrenosum in a patient with granulomatosis with polyangiitis.
• To discuss the diagnostic challenges and management of this dual condition.
• To emphasize the importance of histopathological examination in differentiating similar ulcerative lesions.

Main Methods:

• A 26-year-old male patient with granulomatosis with polyangiitis presented with nasal symptoms and later developed a significant leg ulcer.
• Diagnostic workup included nasal endoscopy, biopsies, and CT scans.
• Treatment involved corticosteroids and cyclophosphamide.

Main Results:

• The patient was initially diagnosed with localized granulomatosis with polyangiitis and treated.
• Three years later, he presented with severe nasal destruction and a large necrotic leg ulcer.
• Histopathology confirmed pyoderma gangrenosum, leading to a diagnosis of co-existing granulomatosis with polyangiitis and pyoderma gangrenosum.
• The patient showed prompt recovery after adjusted immunosuppressive therapy.

Conclusions:

• Skin manifestations are common in granulomatosis with polyangiitis, but classic pyoderma gangrenosum association is rare.
• Distinguishing pyoderma gangrenosum from pyoderma gangrenosum-like ulcers in GPA is clinically challenging.
• Histopathology is essential for accurate diagnosis and guiding treatment decisions.