EMC - Dermatologie-Cosmétologie最新文献

Human papillomavirus (HPV) are responsible for extremely spread cutaneous or mucous tumors : warts, genital warts, papillomas… Anogenital infections by HPV is currently the most frequent of the sexually transmitted diseases. Although generally benign, the infections induced by HPV arouse nevertheless an interest growing since accession to molecular biology and the discovery of the role of these viruses in the genesis of certain cancers.

Cutaneous adverse drug reactions (CADR) are induced by the parenteral, oral, subcutaneous or intramuscular administration of a non-tolerated drug. A strict management of patients suffering from CADR is necessary and must include a description of the clinical features, photography, a chronological table drawn at the onset of the CADR in order to determine which drug is involved in the adverse effect. Urticaria can be due to an allergological or pharmacological mechanism. Vasculitis are related to circulating immune complexes and cannot be reproduced by skin tests. Maculopapular rash is the most common CADR can be difficult to distinguish from a viral rash or a transient drug intolerance during a viral infection. Drug rash with eosinophilia and systemic symptoms (DRESS) can be associated with a severe liver cytolysis. Long lasting relapses of DRESS could be due to secondary reactivation of the human herpes virus 6. Stevens Johnson syndrome and Lyell’s syndrome are due to a keratinocyte apoptosis, with not well elucidated mechanisms. Six months after a CADR, skin tests can be performed in order to determine which drugs have to be forbidden or may be allowed for the patient.

Skin manifestations in patient with malignant hematology diseases are very diverse. Knowledge of these manifestations is important in clinical practice. On one hand, it permits the diagnosis of an unknown malignant hematology diseases, and on the other hand, certain skin lesions can alter the prognosis or therapeutic approach in known disease. These skin manifestations can be split into four categories : specific skin lesions, “satellite” or paraneoplastic lesions, skin infections, and skin lesions induced by chemotherapy. The clinical, and histological aspects of these manifestations are very rich indeed. The specific skin manifestations are often easily diagnosed, but can be mistaken for cases of myelodysplastic syndromes. The satellite manifestations are characterized by neutrophilic dermatoses and vasculitis.The skin infections may be misleading as a result of the neutropenia. Skin biopsy should be repeat for histological, bacteriological, virological, and mycological examinations in patient with malignant hematology diseases.

To date, the pathogenesis of melasma is still unclear and consequently, treatment is frequently disappointing, both for the physician and the patient. Treatment of melasma is difficult and should not be exclusively limited to the formulation of skin lightening preparation. A rapid decrease of pigmentation and clearance of melasma macules may be obtained if some treatment guidelines are taken into account. Examination of the skin with both visible and Wood’s light, and sometimes biopsy are necessary to determine the pattern of the hyperpigmentation. Patients are questioned on the time of melasma onset, relationship of melasma to triggering factors (pregnancy, or oestrogen progesterone ingestion), and to exacerbating factors such as mechanical traumas and sunlight. Finally, an effective skin lightening treatment can be proposed for the epidermal pattern of melasma. However, effective treatment of dermal melasma do not exist currently, except camouflage.

Hypersensitivity vasculitis denomination has been used with various signification since the first description of this entity. Nowadays, it does not correspond to a particular vasculitis, so this term must be abandoned. Contact vasculitis and food-induced vasculitis are rare. It is difficult to prove the responsibility of a drug in a vasculitis, and the detection of antinuclear polynuclear cells antibodies cannot exclude the diagnosis. Giant cell arteritis and Takayasu arteritis concern various aged patients and involve the large artery vessels. Periarteritis nodosa, microscopic polyangiitis, Churg and Strauss syndrome, Wegener granulomatosis are systemic vasculitis well differentiated. The strategy of treatment as become better for these last years. Mixed cryoglobulinemia, often linked to hepatitis C virus infection, are chronicle cutaneous and systemic vasculitis with a particular target on skin, kidney and nervous system. Concerning thromboangiitis obliterans, this entity is located on the edge of vasculitis because e of any impairment of the wall vessel.

Poxviruses are DNA viruses that infect humans and animals. Their strong tropism for the skin explains why skin lesions are consistently present in humans. Smallpox caused devastating epidemics in the past, with mortality rates of about 30%, but was eradicated in 1980 by mass immunization with the vaccinia virus. Orthopoxviruses, such as monkeypoxvirus or cowpoxvirus, cause vesicular eruptions that can be severe but are extremely uncommon. Orf disease and milkers’ nodules are caused by parapoxviruses that usually infect livestock. Both diseases manifest as pseudotumoral nodules over the limbs that clear spontaneously. Molluscum contagiosum presents as shiny umbilicated papules and is seen mainly in children and young adults. In patients with cell-mediated immune deficiencies, most notably due to HIV infection, molluscum contagiosum lesions are more common than in the general population, often profuse, and difficult to treat.