[Cutaneous mucormycosis caused by Rhizopus microsporus]. / Mucormycose cutanée à Rhizopus microsporus.

BACKGROUND: Mucormycosis are rare fungal infections occurring chiefly in the lung or the rhinocerebral compartment, particularly in patients with immunodeficiency or mellitus diabetes. We report the case of an elderly patient with cutaneous mucormycosis caused by Rhizopus microsporus. PATIENTS AND METHODS: An 89-year-old man presented a skin lesion of the forearm rapidly becoming inflammatory and necrotic. The patient had been treated for 2months with oral corticosteroids for idiopathic thrombocytopenia. Histological and mycological examination of the skin biopsy revealed the presence of a filamentous fungus, R. microsporus. The outcome was unfavorable, despite prescription of high-dose liposomal amphotericin B. DISCUSSION: Mucormycosis are infrequent opportunistic infections caused by angio-invasive fungi belonging to the Mucorales order. Cutaneous presentations are rare, and in rare cases the species R. microsporus is isolated in clinical samples. Diagnosis is based on histological examination highlighting the characteristic mycelium within infected tissue, together with ex vivo mycological identification using morphological and molecular methods. Treatment consists of liposomal amphotericin B combined with debridement surgery. CONCLUSION: R. microsporus is a marginal fungal species rarely isolated in clinical practice, and even less in dermatology departments. This clinical case report highlights the severity of infection with this fungus, particularly in the absence of early surgery.

[Interferon-alpha and ribavirin treatment in a patient with hepatitis C virus-associated cutaneous periarteritis nodosa]. / Périartérite noueuse cutanée associée à une infection par le virus de l'hépatite C, régressive après une bithérapie antivirale.

BACKGROUND: Hepatitis C virus (HCV) frequently causes leucocytoclastic vasculitis as a result of type II or III cryoglobulinemia. HCV-associated vasculitis without cryoglobulinemia is less common. PATIENTS AND METHODS: A 33-year-old woman consulted for infiltrative necrotic purpura of the lower limbs, responsible for leg ulcers measuring less than 1 cm. Histopathological examination revealed vasculitis affecting the hypodermic arterioles and caused by periarteritis nodosa. No extracutaneous involvement was observed. The patient had presented asymptomatic untreated HVC infection (genotype 3) for two years. Antiviral treatment resulted in elimination of the patient's viremia and no relapse of skin lesions was observed two years after the end of treatment. COMMENTS: This patient presented vasculitis due to cutaneous nodular periarteritis associated with HVC without cryoglobulinemia. Hepatic impairment was mild and did not require any antiviral treatment. No further skin involvement was seen after treatment with colchicine and because the patient's viral genotype was favorable, we decided to initiate antiviral therapy. This therapeutic approach should be considered by dermatologists, but it is nevertheless important to assess the risk of interferon-induced aggravation of vasculitis.

Trichoepithelioma with "monster" stromal cells.

Trichoepithelioma is a benign tumor of trichogenic origin which appears predominantly in childhood or in young adults. Different forms have been described according to clinical and histological features. The authors report a unique variant of trichoepithelioma arising on the limb of a 27-year-old man. The tumor was characterized by the mixture of an atypical fibroxanthomatous proliferation and basaloid epithelial strands of trichoepithelioma. Such histological features have not been previously reported. It raises the question of an additional variant of hair follicle tumor with a mixed epithelial and mesenchymal proliferation.