Urticaria Multiforme: A Report of 5 Cases and a Review of the Literature

A case of urticaria multiforme with unusual presentation

“…pharyngitis, otitis media and upper respiratory infections), drugs (e.g., furazolidone, amoxicillin, nitrofurantoin), and immunizations. 2,3,9 Other associated findings include pruritus as the most prominent symptom, facial or acral angioedema, or both, dermographism, and fever. 2 UM can be conveniently diagnosed using clinical evaluation alone, without need of any skin biopsy or extensive laboratory investigations.…”

“…Oral corticosteroids can be given in refractory cases. 2,5,9 UM is underrecognized as a result of the paucity of reported cases in the literature mainly due to similarities between distinct clinical entities. 10 The differential diagnosis of such lesions include erythema multiforme (EM), Serum-Sickness-Like Reactions (SSLR), urticarial vasculitis, and acute hemorrhagic edema of infancy which have different pathogenesis, prognosis, and management.…”

“…10 The differential diagnosis of such lesions include erythema multiforme (EM), Serum-Sickness-Like Reactions (SSLR), urticarial vasculitis, and acute hemorrhagic edema of infancy which have different pathogenesis, prognosis, and management. 1,2,6,9 An overview and update of the clinical findings, etiologies, histopathology, management, and complications of urticaria multiforme mimickers is listed in (Tables 1). [4][5][6]10 Erythema multiforme is the most common misdiagnosis.…”

“…On the other hand, UM lesions are transient and pruritic, with positive dermographism and histologically show classical findings of a typical urticaria, revealing dermal edema and perivascular lymphocytic infiltrate with few eosinophils, as in this case. [1][2][3]9,10 Also, serum-sickness-like eruptions can manifest as polycyclic wheals with angioedema like UM lesions. This disease is distinguished by its fixed skin lesions that can last days to weeks, with high fever, myalgia, arthralgia, and lymphadenopathy.…”

“…These patients can also show other signs and symptoms such as fever, nephritis, arthralgia, and uveitis. 6,9 Finally, acute hemorrhagic edema of infancy is a variant of cutaneous small vessels leukocytoclastic vasculitis, that is thought to be caused by an immune complexmediated (Type III) hypersensitivity reaction in response to infection, vaccination, or medication intake characterized with acral edema, fever, and purpuric lesions in children younger than two years old. The lesions can assume an urticarial aspect but are purpuric and last longer than the ones seen in UM, leaving a residual hyperpigmentation.…”