ERYTHEMA ELEVATUM DIUTINUM
Authors: FARELLA VITTORIA , LOTTI TORELLO , DIFONZO ELISA M. , PANCONESI EMILIANO X. 
Published: May 2007

A 57‐year‐old woman presented with symmetrical reddish‐brown plaques on the entire skin, especially the extremities. The lesions differed in size and shape, and their consistency ranged from soft to tight‐elastic, to hard in the older lesions (Fig. 1). The forearms and the dorsae of the hands and feet were covered with confluent plaques; some of these had an isolated nodular lesion on top. The lesions on the arms were papular‐nodular, arranged in rows to form “cords” with “pseudokeloid” appearance (Fig. 2). On the face, around the cheeks, the wings of the nose, and the ears, there were purplish nodular lesions and plaques.

The lesions first appeared 14 years ago in the winter as lentile‐sized, slightly reddish papules on both legs. These lesions disappeared spontaneously during the summer and returned the following winter. For 4 years the lesions followed this pattern of appearing and disappearing, leaving residual pigmentation. The patient reported that at each recurrence the lesions were larger and darker. Subsequently, the lesions had become permanent without any improvement during the summer and had also spread to the upper limbs and trunk. For the past 4 years the patient has had arthralgia of the large joints, swelling of the lower extremities, burning and pain in the lesions themselves. These symptoms became more evident in the evening and after exposure to cold.

A biopsy specimen of a recent lesion showed a dermal perivascular infiltrate comprised mainly of neutrophilic granulocytes and histiocytes and a few eosinophils. The vessels appeared dilated with swelling of the endothelial cells (Fig. 3). In and around the vessel walls an eosinophilic deposit of fibrinoid material was noted.

Electronmicroscopic examination revealed macrophages with secondary lysosomes containing electrondense, osmiophilic, probably lipid material, in the perivascular infiltrate. lnterdigitate cells, juxtaposed with the lymphocytes among the infiltrate cells were also seen (Fig. 4).

Direct immunofluorescence (DIF) revealed linear IgA deposits at the dermoepidermal junction. Direct immunofluorescence on healthy perilesional skin after histamine injection1 showed IgA, C3, and fibrinogen at the perivascular level in the superficial dermis and at the dermoepidermal junction with granular appearance.

Cutaneous fibrinolytic activity (CFA) evaluated with Todd's autohistographic method1, modified by Lotti et al.2, was reduced by 80% compared to that of healthy subjects.

Findings of other laboratory tests are listed in Table 1. Relevant investigations showed a decrease in fibrinogen, positive protein C and RA tests, the presence of cryoglobulin, and an increase in serum |gA.| Circulating immune complexes were detected and glucose‐6‐phosphate‐dehydrogenase (GG‐PD) was slightly low. The tests of clotting function showed some changes due to increased platelet aggregability from exogenous adenosine diphosphate (ADP), a slight reduc‐tion in fibrinogenemia due to the presence of D‐dimers and other products of fibrinogen degradation, suggesting a state of chronic intravascular coagulation.

Treatment was begun with diaminodiphenylsulfone (50 mg/day), which was suspended because of adverse reac‐tions (headache and nausea) and was replaced by clofa‐zimine (starting dose 200 mg/day). Improvement in the sub‐jective symptoms and healing of many lesions with residual pigmentation was noted.