Introduction Demographics Causes Clinical features Diagnosis Differential diagnoses Treatment Outcomes and complications
Recurrent cutaneous necrotising eosinophilic vasculitis is a rare form of small vessel vasculitis, consisting of pruritic papules, purpura, angioedema, and peripheral blood eosinophilia. Recurrent cutaneous necrotising eosinophilic vasculitis is an eosinophilic subtype of cutaneous small vessel vasculitis. It was first described in 1994 [1].
Recurrent cutaneous necrotising eosinophilic vasculitis has been described in patients aged 17–81 years and affects both men and women equally. No predilection for age, sex, or ethnicity has been reported [1].
Recurrent cutaneous necrotising eosinophilic vasculitis is thought to be idiopathic as no triggers or causes have been identified.
The pathogenic mechanism behind recurrent cutaneous necrotising eosinophilic vasculitis is not fully understood; however, it is likely a result of eosinophil-mediated vascular damage. Similar to other eosinophilic disorders, interleukin 5, platelet-activating factors, and complement C4 may have a role in the pathogenesis by increasing vascular permeability [2].
The dermatological manifestations of recurrent cutaneous necrotising eosinophilic vasculitis can occur anywhere on the body, and include:
Most affected patients report a long history of recurrent pruritic papules, typically over the lower limbs. Systemic features, such as fevers, weight-loss arthralgias, and the visceral involvement typically associated with systemic vasculitides, are not usually present [3].
On peripheral blood examination, the eosinophil count is often elevated in recurrent cutaneous necrotising eosinophilic vasculitis.
The histopathological examination of recurrent cutaneous necrotising eosinophilic vasculitis shows a dermal small vessel vasculitis with fibrinoid necrosis of the vessel walls, but no leukocytoclasis is present. There is exclusive eosinophilic infiltration throughout the dermis. Tryptase staining shows increased mast cells in the perivascular areas of the dermis [3].
Indirect immunofluorescence reveals extensive intracellular and extracellular deposition of major basic protein and eosinophil-derived neurotoxin around the dermal vessels [3].
A thorough workup should be performed to rule out underlying systemic conditions. This may include full blood examinations; biochemical and immunological tests, especially tests for antineutrophil cytoplasmic antibodies (ANCAs); a peripheral blood film; and a bone marrow biopsy if indicated.
The differential diagnoses for recurrent cutaneous necrotising eosinophilic vasculitis include:
Recurrent cutaneous necrotising eosinophilic vasculitis responds to the use of oral corticosteroids as initial and maintenance therapy [2–4].
In the longer term, patients may require low-dose or alternate daily glucocorticoids, as recurrences of the condition after the discontinuation of therapy are common. Other agents that have been used in case reports include:
There are little data about the long-term outcomes of recurrent cutaneous necrotising eosinophilic vasculitis. However, a benign course is assumed given the steroid-responsiveness of the condition [4].
Some patients may require long-term corticosteroid therapy.
Potential complications include steroid-related side effects, ulceration, and secondary infection [1].
