[Sclerodermatous changes in porphyria cutanea tarda: six cases]

International audienceBACKGROUND: The clinical features of porphyria cutanea tarda (PCT) are usually distinctive and include blistering on sun-exposed areas, fragile skin, hypertrichosis and hyperpigmentation. Sclerodermatous changes are much less common, and may either reveal PCT or else appear later. We carried out a retrospective study of the files of six female patients presenting such lesions. PATIENTS AND METHODS: Six women (age: 45 to 72 years) were referred for sclerodermatous lesions on sun-exposed areas of the upper body. In four patients, these lesions revealed PCT and in the remaining two patients they were indicative of previously treated but relapsing PCT. Four had sclerodermatous skin changes mimicking morphea of the neck and neckline, the top of the back and the face, while one presented more diffuse facial and cervical sclerosis. Associated alopecia was seen in three patients. The last patient presented isolated sclerodermiform alopecia. Associated malar hypertrichosis was seen in five cases and facial hyperpigmentation was noted in three cases. Four exhibited no blisters, cutaneous fragility, milia or photosensitivity. Histological findings were consistent with morphea or scleroderma in all cases. All patients presented abnormal liver tests: cirrhosis was present in four cases (primitive biliary cirrhosis, alcoholic cirrhosis and hepatitis C) and fatty liver in two cases. In four cases, there was excessive alcohol intake. Uroporphyrin levels were above the normal range in all cases. Local corticosteroid therapy associated with phlebotomy and/or low-dose hydroxychloroquine resulted in complete normalisation of porphyrin levels in four patients, with complete resolution of the cutaneous lesions in two patients and partial improvement in the other two. DISCUSSION: Sclerodermatous changes are uncommon in PCT. They are not always late and secondary to the process of healing of blisters but can in fact constitute the first cutaneous symptom of the disease while revealing the underlying liver disease. Even in the absence of blisters, photosensitivity or cutaneous fragility, a diagnosis of PCT must be suspected in a setting of sclerodermatous changes distributed on the neck and face, or the neckline, or scarring alopecia, if associated with abnormal liver tests. Skin biopsy to confirm the diagnosis of scleroderma may delay the diagnosis, which is in fact based on porphyrin level. Normalization of the latter parameter under treatment allows regression of lesions