Asymmetrical periflexural exanthem exhibiting pseudoisomorphic Köebner response in an adult

Abstract

Asymmetrical periflexural exanthem is a rare clinical condition, seen almost exclusively in children. Very few adult cases have been reported in the literature. We report a case of this rare eruption in an adult man showing characteristic clinical and histological features. Interestingly, this patient also exhibited a pseudoisomorphic Köebner response. Although an infective aetiology of viral origin has been suggested for this localized eruption, the aetiology remains unknown. We are of the opinion that the pseudoisomorphic Köebner response in this patient may support the inoculation hypothesis in the pathogenesis of this disorder.

Viral infections of the folds (intertriginous areas)

“…[44][45][46][47][48][49][50] Histologic findings are non-specific but shows a perivascular upper dermal lymphocytic infiltrate though some authors emphasize a lymphocytic infiltrate around sweat glands to be a diagnostic clue for the disease. 45,48 The etiology of the disease is unknown but the possible seasonal nature of the eruption, the occurrence of small epidemics, the frequency of associated upper respiratory tract prodromes, the lack of response to antibiotics and the occurrence in small children, are the features suggesting a viral origin. 48,50 To date evidence of PVB19 infection was found only in two adult patients with APE.…”

“…34,38,39 Apart from these well-known manifestations of the infection, PVB19 infection has also been implicated in several other lesser-known exanthems [40][41][42][44][45][46][47][48][49][50] Baboon like erythema of the Parvoviruses: Baboon syndrome is a disease that shows symmetrical areas of erythema on the axillae, inner side of the thighs, flexural areas such as the antecubital and popliteal fossae, buttocks and anogenital area. Baboon syndrome is known to be induced by systemic contact dermatitis to contact allergens such as mercury and nickel, and recently cases related with infectious agents and many other drugs have been reported.…”

“…[34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] Papular-purpuric gloves and socks syndrome is an acute self limiting pruritic dermatosis that affects the distal extremities in a gloves and socks pattern. PPGSS presents initially with erythema and popular oedema and may also be associated purpura and rarely petechiae.…”

“…[44][45][46][47][48][49][50] Hands and feet are spared. Though the most common presentation is maculopapular exanthem, purpuric lesions, or not coalescening discrete erythematous papules have been also described in the APEC.…”

“…Apart from itching and local lymphadenopathy which is found in about 50% of cases, the disease has a favorable course and lesions resolves in about four weeks without scarring. [44][45][46][47][48][49][50] This disease is almost exclusively occur in children aged 1-5 years. However there are case…”