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Scleredema
Scleredema
Clinical features Scleredema (Buschke) is a rare primary mucinosis that presents with nonpitting indurated edema and associated dermal hardening in the absence of any significant clinical abnormality of the overlying skin.1,2 Three distinct subtypes are recognized:2โ5
โข Most commonly seen is an acute variant predominantly affecting children and characterized by a rapid onset arising a few weeks after an infection, most often of the upper respiratory tract. Streptococcal infections are particularly implicated, but cases have followed a variety of viral illnesses including measles, mumps, influenza, cytomegalovirus infection, chickenpox, and Mycoplasma pneumoniae infection.6โ9 Scleredema has also occurred in the setting of chronic scabies and secondary streptococcal infection.10 Although many of these cases resolve spontaneously within a period of months and years, a significant number are persistent and exacerbations are not uncommon.11 Females are affected more often than males and the disease is more common in the winter months.12 Sometimes there is a prodromal illness of malaise, myalgia, generalized myasthenia, and arthralgia.11 Some patients develop a variety of cutaneous manifestations including transient erythema, urticarial or annular eruptions, and dermographism before the onset of the more typical features.4 Scleredema in children may exceptionally present overlapping features with eosinophilic fasciitis.13
โข Secondly, scleredema may have an insidious onset unaccompanied by any previous acute illness.2
โข Lastly, scleredema sometimes develops in association with late-onset diabetes mellitus. Patients, more often males, are often obese and there are usually other manifestations of diabetes, including nephropathy, hypertension, coronary and peripheral vascular insufficiency, retinopathy, and peripheral neuropathy.2,14,15 The diabetes commonly precedes the development of scleredema, which is usually widespread and associated with a chronic course.1,16,17 This variant of scleredema does not tend to resolve spontaneously or with treatment, though there have been reports with improvement with combinations of PUVA and colchicine or UVA with or without colchicine.18โ20
The eruption consists of densely grouped, firm, 1โ2โฏmm papules on the elbows and smaller numbers of more dispersed lesions about the forearms and dorsa of the hands.1 Congenital linear papules on the backs of two fingers have been reported in one infant and another was born with clustered papules on the lower back.2,3 Another patient presented with a cobblestoned plaque on the thigh.4 Congenital cases presenting with papules on the fingers and toes or widespread eruption involving the trunk, neck, and extremities have been described.7,8 Owing to the paucity of cases, the natural history and prognosis of this condition are unknown, though some lesions spontaneously regress.7,8
Histologic features Excessive mucin (hyaluronic acid) is present in the papillary and/or reticular dermis under a variably acanthotic epidermis.1,7,8 Sectioning artifact may make the deposits appear to have an intraepidermal location.1 Biopsies from late lesions show features identical to those of lichen myxedematosus with fibrosis and proliferation of dermal fibroblasts.4 A perivascular chronic inflammatory cell infiltrate is evident in the superficial dermis.