Eosinophilic granulomatosis with polyangiitis: Cutaneous clinical and histopathologic differential diagnosis

Abstract

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare, but severe systemic vasculitis that can affect skin and other organ systems. Diagnostic criteria have evolved, and many attempts have been made to classify the vasculitides based on clinical and/or histopathologic features, with an aim to develop standardized criteria.According to the EGPA Consensus Task Force recommendations, EGPA is a syndrome of asthma, eosinophilia, pulmonary infiltrates, and extrapulmonary vasculitis (such as cutaneous involvement with purpura). Histopathologic evidence of vasculitis in EGPA may be associated with eosinophilic infiltration and/or perivascular granulomatous inflammation. We review clinicopathologic criteria of this enigmatic vasculopathy.

Umbilicated papulonodules on the elbows with purpuric papules on the fingers

“…Necrosis, superficial ulcerations, necrobiosis and a predominant neutrophilic infiltrate with few histiocytic collections were the main features in our case. The histopathological differential diagnoses of CSS include GPA, polyarteritis nodosa (PAN) and other small vessel vasculitis such as cryoglobulinaemic and IgA vasculitis 3 . GPA shows vasculitis of small dermal vessels with neutrophils, sometimes with granulomatous inflammation around the vessels, while PAN usually shows vasculitis of medium vessels with predominantly neutrophils, and cryoglobulinaemic and IgA vasculitis shows primarily small vessel vasculitis without granulomas 3 .…”

“…The histopathological spectrum in CSS ranges from necrotizing leucocytoclastic vasculitis with eosinophils to granulomatous vasculitis of small and medium vessels to extravascular necrotizing granulomas 3 . Purpuric lesions usually show necrotizing vasculitis of the small dermal vessels with or without eosinophils, whereas eosinophilic or granulomatous vasculitis of the deep dermal to subcutaneous muscular vessels usually manifest as nodular lesions or livedo reticularis 4 .…”

From Churg–Strauss Syndrome to Eosinophilic Granulomatosis With Polyangiitis: A Historical Review of Nomenclature and Diagnostic Criteria

“…23 When angiocentric inflammation is present, small arteries and venules are most often affected whereas muscular arteries in the subcutis are less commonly involved. 25 Cutaneous lesions are reported to occur in 60%–70% of patients and prominent tissue eosinophils in a vascular, perivascular, or interstitial dermal distribution are the most consistent reported finding. 24…”

Eosinophilic Granulomatosis with Polyangiitis: Latest Findings and Updated Treatment Recommendations

“…Skin lesions are observed in 40–50% of cases. The most common lesion is palpable purpura, followed by livedo, erythema, and blisters [ 6 , 67 , 68 , 69 , 70 ]. Eosinophil-rich leukocytoclastic vasculitis and neutrophilic granulomatosis are often observed [ 6 , 70 ].…”

“…The most common lesion is palpable purpura, followed by livedo, erythema, and blisters [ 6 , 67 , 68 , 69 , 70 ]. Eosinophil-rich leukocytoclastic vasculitis and neutrophilic granulomatosis are often observed [ 6 , 70 ]. Gastrointestinal involvement, such as ulceration and perforation, is observed in approximately 30% of the patients [ 71 , 72 ] and is considered a poor prognostic factor [ 15 , 16 ].…”