Monday, January 10, 2011

Striated lichen

Lichen striated Linear Lichen striatum is a rare dermatosis, benign self-limiting of unknown origin that predominantly affects children. It is recognized based on appearance or clinical development and characteristics of Blaschko lines. Lichen striatum appears as a sudden eruption of small papules on the extremities. Papules are usually asymptomatic reaching maximum damage in a few days to weeks. When patients are symptomatic the most common accusation is itching. Lichen striatum is self-limited but can be solved with hyper or hypopigmentation postinflamatorie. It most often affects young children. Over 50% of cases occur in children between 5-15 years.
The cause of lichen striatum is unknown. The most popular hypothesis is that the combinations of genetic and environmental factors. Atopy can be involved and many people associate and asthma, atopic dermatitis or allergic rhinitis. Abnormal autoimmune response may also play an important role. Since striated lichen is a self-limiting illnesses and injuries resolve in 3-12 months, and requires no treatment. Nail may indicate a progressive evolution. To prevent and reduce complications and morbidity can be given corticosteroids. They have anti-inflammatory effects and alter the body's response to different stimuli. You can use topical corticosteroids and emollients to treat dryness and itching associated. The prognosis of patients with lichen striatum is excellent. Recovery is complete. Lesions usually regress spontaneously assemble year. Relapses may occur but are unusual. Hyper or hypopigmentation postinflamatorie may persist several months after the condition is resolved.
Pathogenesis and causes
The skin is the main organ affected. Still may be involved and nails. Striated lichen lesions following Blaschko lines. These lines are thought to be embryological origin. Segmental growth are the result of skin cells or clones of cutaneous mosaicism induced mutations. The etiology of lichen striatum is unknown. The most accepted hypothesis is one that involves a combination of predisposing factors and environmental factors genetigi. Atopy may be a predisposing factor. Some patients with lichen and associated striatum atopic dermatitis, asthma, allergic rhinitis. An autoimmune response may be involved. It postulates that the task would trigger the autoimmune response leads to the eruption.
Infection from the environment may be involved. Seasonal variations and family clusters of cases suggests a viral factor. Striatum has been reported after vaccination with BCG lichen and hepatitis B, after UV exposure and after infection with chickenpox.
Signs and symptoms
Lichen striatum is a disease of children. Over 50% of cases occur in children between 5-15 years. Although it is rare in adults can occur at any age. It appears as a sudden eruption of small papules on the extremities. Papules are usually asymptomatic, the disease peaks in a few days or months. When patients are asymptomatic most common accusation is itching. Lichen striatum is self-limited but can be solved with hyper or hypopigmentation postinflamatorie.
Physical examination. Lichen striatum appears as a continuous or interrupted band consisting of lichenoid papules pink or tan-colored, 1-3 mm. They can be soft or flat carcinoma. Occasionally this ocomponenta vesicular. The band can vary from 1-2 cm up to several inches wide and can reach the entire length of the member. The lesions are usually unilateral and single band on one end along the lines of Blaschko. In rare cases may be bilateral or multiple parallel lanes. They are often located on the proximal extremity and less frequently on the trunk, head, neck or thighs. The darker people eruptions may occur as a band of hypopigmentation.
Nail is unusual. Nail injuries can occur before or simultaneously with skin lesions. May represent one area of damage. Frequently only the medial or lateral portions are involved and damage is restricted to a single nail. Nail changes include longitudinal thickening, splitting, onycholysis, nail loss, nail bed hyperkeratosis, thinning or thickening of the nail, onicodistrofie, leuconichie dotted or striped and curved nails.
Diagnosis
Laboratory studies: -In cases of doubt can make direct immunofluorescence to differentiate from lichen planus -Skin biopsy may be performed to confirm diagnosis -Tests for IgM, IgG and complement C3 are positive and negative for lichen planus lichen striatum.
Histological examination. The results depend on the stage of evolution of lichen. It can be seen with reactive epidermal polymorphic spongiotice and lichenoid changes. Girl Lichen Planus, lichen streaked limfohistiocitic shows perivascular infiltrates extending deep into the dermis and surrounding hair follicles and eccrine glands. Granulomatous inflammation may be present. The differential diagnosis is made with urmataorele disease: lichen nitidus, Lichen Planus, Lichen simplex chronic porokeratoza, pasoriazis, nongenitale warts, tinea corporis, Darier disease, drug eruption.
Treatment
Because the disease is self-limited lichen streaked, and the lesions regress in 3 to 12 months, no treatment is required. Lichen streaked nail predisposes to a prolonged evolution. It resolves spontaneously in 30 months without deformation. To reduce morbidity and prevent complications can choose to corticosteroids. The effects of modulation of inflammatory and immune response of the body to various stimuli may be helpful. Topical and intralesional steroids do not improve the condition, but emolientele and topical steroids may be used for dryness and itching associated. Examples: triamcinolone, clobetasol. Examples of immunomodulators that have been used with success in treating lichen striatum are tacrolimus and pimecrolimus.
Prognosis The prognosis of patients with lichen striatum is excellent. Recovery is complete. In a year lesions regress spontaneously. Relapses may occur but are rare. Hyper and hypopigmentation postinflamatorie may require up to 30 months to deliver.

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