dr angeleyes
04-09-2009, 06:46 PM
Lichen Sclerosus et Atrophicus
Introduction
Background
Lichen sclerosus (LS) is a chronic inflammatory dermatosis that results in white plaques (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) with epidermal atrophy. Lichen sclerosus has both genital (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) and extragenital presentations. It is reported under a variety of other appellations such as lichen sclerosus et atrophicus (dermatological literature), balanitis xerotica obliterans (glans penis (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) presentation), and kraurosis vulvae (older description of vulvar presentation). An increased risk of squamous cell carcinoma may exist in vulvar disease, but the precise increase in risk and what cofactors (human papillomavirus infection or prior radiotherapy) may be involved are not yet completely defined. In large series, genital presentations, both vulvar and penile, outnumber extragenital reports by more than 5:1
.
Pathophysiology
Inflammation and altered fibroblast function in the papillary dermis leads (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) to fibrosis of the upper dermis. Genital skin and mucosa are affected most frequently, but extragenital lichen sclerosus does occur, and even rare oral (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) presentations are reported. Several studies have recently identified the presence of autoantibodies to the glycoprotein extracellular matrix protein 1 (ECM1).1 This may be associated with histologic evidence of vasculitis in some cases and may lead to reduplication of the basement membrane in blood vessel walls.2 The exact role of these antibodies and the changes seen in the microvasculature are currently under investigation.3
The effect of cell-mediated cytotoxicity has been better defined at the biochemical level.4 Systemic disease or involvement of other organ systems, unlike scleroderma, is not described, although many more authors are describing lichen sclerosus and scleroderma as closely related entities; many cases of coexistent lichen sclerosus/scleroderma have been reported.
Frequency
International
The population rate is unknown. Male genital lichen sclerosus is seen almost exclusively in uncircumcised men (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) and boys (http://javascript%3Cb%3E%3C/b%3E:void%280%29;). The rate of circumcision in a given population would thus influence the rate in this subset
.
Mortality/Morbidity
Lichen sclerosus has no associated increased mortality unless the patient develops a malignancy in the area. Cancer arising in extragenital presentations is described only rarely and may be coincident with other factors. Many pediatric cases will improve with puberty. Extragenital cases and many genital cases are asymptomatic except for the cosmetic aspect or pruritus. Recalcitrant cases, especially those associated with erosion or progressive scarring, may result in severe sexual dysfunction
.
Race
Lichen sclerosus, both genital and extragenital, has no known racial predilection
.
Sex
The male-to-female (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) ratio is 1:6 , with female genital cases making up the bulk of reports
.
Age
Up to 15% of cases are in children with the majority being vulvar presentations. A study of foreskins submitted after therapeutic circumcision for phimosis revealed many cases of unrecognized lichen sclerosus. Extragenital lichen sclerosus is rare in children
.
Clinical
History
Extragenital lichen sclerosus may be asymptomatic or it may itch, although itching is not common. Vulvar lichen sclerosus usually presents with progressive pruritus, dyspareunia, dysuria, or genital bleeding. Penile lichen sclerosus usually is preceded by pruritus but may present with sudden phimosis of previously retractable foreskin, and urinary obstruction can result
.
Physical
Pertinent physical findings are limited to the skin.
* Skin primary lesion
o Lichen sclerosus usually begins as white, polygonal papules that coalesce into plaques. Evenly spaced dells or comedolike plugs (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) correspond to obliterated appendiceal ostia. With time, the plugs and dells will disappear and leave a smooth, porcelain (http://javascript%3Cb%3E%3C/b%3E:void%280%29;)-white plaque. The size of the plaque or plaques may vary widely from a few millimeters resembling lichen nitidus to the entire upper trunk.
o Vulvar lichen sclerosus may progress to gradual obliteration of the labia minora and stenosis of the introitus. The most common variation occurs when the inflammation is intense enough to cause separation of a large area of epidermis, creating blisters or large, occasionally hemorrhagic, bullae. Because this occurs more often in genital cases, it may be confused with the trauma of sexual abuse or other genital ulcerative disease.
o Given the high frequency of genital mucosal disease, it is surprising that more oral cases have not been reported. Those rare cases reported are usually seen in patients with widespread, generalized lichen sclerosus. Some believe that many cases of clinically diagnosed lichen planus may actually be lichen sclerosus and that isolated oral mucosal lichen sclerosus may not be as rare as is thought.
* Skin distribution
o Extragenital lesions (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) may occur anywhere on the body, although the back and shoulders are reported most commonly. Female genital lesions (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) may be confined to the labia majora but usually involve and eventually obliterate the labia minora and stenose the introitus. Often, an hourglass, butterfly, or figure-8 pattern involves the perivaginal and perianal areas, with minimal involvement of the perineum in between.
o Male genital lesions usually are confined to the glans penis and the prepuce or foreskin remnants. Penile shaft involvement is much less common, and scrotal involvement is rare. The initial manifestation may be a sclerotic ring at the prepuce edge.
o The isomorphic (Koebner) phenomenon is described in this condition, with the resultant lesions in old surgical (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) scars (http://javascript%3Cb%3E%3C/b%3E:void%280%29;), burn (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) scars, sunburned areas, and areas subject to repeated trauma. Distribution of lichen sclerosus along the lines of Blaschko was described in an extragenital case.
Skin color is white, often with a shiny (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) porcelain appearance. Telangiectases and follicular plugs may be seen
.
Causes
The cause of lichen sclerosus is unknown. Over the years, a number of etiologies have been proposed. Several studies have linked borrelial or other infections with lichen sclerosus,5 yet other studies have disputed this. This concept has reemerged with European reports demonstrating Borrelia more readily in lichen sclerosus cases using “focus-floating microscopy” than conventional histology.6 Genetic and autoimmune factors have been explored without identification of consistent, reproducible patterns, although autoantibodies to ECM1 have now been reported by several independent authors. Increased circulating autoantibodies may be as high as 28%, comparable to the rate seen in bullous lichen planus.7
Local irritation seems to play (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) a role in some cases, but the sequence of events that leads to the altered fibroblast function, microvascular changes, and hyaluronic acid accumulation in the upper dermis continues to be researched. A lichen sclerosus relative risk factor of 2.5 was seen in premenopausal women placed on oral contraceptives, which, once again, brings up an altered hormonal axis as a possible contributory factor.
mn2ool
Introduction
Background
Lichen sclerosus (LS) is a chronic inflammatory dermatosis that results in white plaques (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) with epidermal atrophy. Lichen sclerosus has both genital (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) and extragenital presentations. It is reported under a variety of other appellations such as lichen sclerosus et atrophicus (dermatological literature), balanitis xerotica obliterans (glans penis (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) presentation), and kraurosis vulvae (older description of vulvar presentation). An increased risk of squamous cell carcinoma may exist in vulvar disease, but the precise increase in risk and what cofactors (human papillomavirus infection or prior radiotherapy) may be involved are not yet completely defined. In large series, genital presentations, both vulvar and penile, outnumber extragenital reports by more than 5:1
.
Pathophysiology
Inflammation and altered fibroblast function in the papillary dermis leads (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) to fibrosis of the upper dermis. Genital skin and mucosa are affected most frequently, but extragenital lichen sclerosus does occur, and even rare oral (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) presentations are reported. Several studies have recently identified the presence of autoantibodies to the glycoprotein extracellular matrix protein 1 (ECM1).1 This may be associated with histologic evidence of vasculitis in some cases and may lead to reduplication of the basement membrane in blood vessel walls.2 The exact role of these antibodies and the changes seen in the microvasculature are currently under investigation.3
The effect of cell-mediated cytotoxicity has been better defined at the biochemical level.4 Systemic disease or involvement of other organ systems, unlike scleroderma, is not described, although many more authors are describing lichen sclerosus and scleroderma as closely related entities; many cases of coexistent lichen sclerosus/scleroderma have been reported.
Frequency
International
The population rate is unknown. Male genital lichen sclerosus is seen almost exclusively in uncircumcised men (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) and boys (http://javascript%3Cb%3E%3C/b%3E:void%280%29;). The rate of circumcision in a given population would thus influence the rate in this subset
.
Mortality/Morbidity
Lichen sclerosus has no associated increased mortality unless the patient develops a malignancy in the area. Cancer arising in extragenital presentations is described only rarely and may be coincident with other factors. Many pediatric cases will improve with puberty. Extragenital cases and many genital cases are asymptomatic except for the cosmetic aspect or pruritus. Recalcitrant cases, especially those associated with erosion or progressive scarring, may result in severe sexual dysfunction
.
Race
Lichen sclerosus, both genital and extragenital, has no known racial predilection
.
Sex
The male-to-female (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) ratio is 1:6 , with female genital cases making up the bulk of reports
.
Age
Up to 15% of cases are in children with the majority being vulvar presentations. A study of foreskins submitted after therapeutic circumcision for phimosis revealed many cases of unrecognized lichen sclerosus. Extragenital lichen sclerosus is rare in children
.
Clinical
History
Extragenital lichen sclerosus may be asymptomatic or it may itch, although itching is not common. Vulvar lichen sclerosus usually presents with progressive pruritus, dyspareunia, dysuria, or genital bleeding. Penile lichen sclerosus usually is preceded by pruritus but may present with sudden phimosis of previously retractable foreskin, and urinary obstruction can result
.
Physical
Pertinent physical findings are limited to the skin.
* Skin primary lesion
o Lichen sclerosus usually begins as white, polygonal papules that coalesce into plaques. Evenly spaced dells or comedolike plugs (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) correspond to obliterated appendiceal ostia. With time, the plugs and dells will disappear and leave a smooth, porcelain (http://javascript%3Cb%3E%3C/b%3E:void%280%29;)-white plaque. The size of the plaque or plaques may vary widely from a few millimeters resembling lichen nitidus to the entire upper trunk.
o Vulvar lichen sclerosus may progress to gradual obliteration of the labia minora and stenosis of the introitus. The most common variation occurs when the inflammation is intense enough to cause separation of a large area of epidermis, creating blisters or large, occasionally hemorrhagic, bullae. Because this occurs more often in genital cases, it may be confused with the trauma of sexual abuse or other genital ulcerative disease.
o Given the high frequency of genital mucosal disease, it is surprising that more oral cases have not been reported. Those rare cases reported are usually seen in patients with widespread, generalized lichen sclerosus. Some believe that many cases of clinically diagnosed lichen planus may actually be lichen sclerosus and that isolated oral mucosal lichen sclerosus may not be as rare as is thought.
* Skin distribution
o Extragenital lesions (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) may occur anywhere on the body, although the back and shoulders are reported most commonly. Female genital lesions (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) may be confined to the labia majora but usually involve and eventually obliterate the labia minora and stenose the introitus. Often, an hourglass, butterfly, or figure-8 pattern involves the perivaginal and perianal areas, with minimal involvement of the perineum in between.
o Male genital lesions usually are confined to the glans penis and the prepuce or foreskin remnants. Penile shaft involvement is much less common, and scrotal involvement is rare. The initial manifestation may be a sclerotic ring at the prepuce edge.
o The isomorphic (Koebner) phenomenon is described in this condition, with the resultant lesions in old surgical (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) scars (http://javascript%3Cb%3E%3C/b%3E:void%280%29;), burn (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) scars, sunburned areas, and areas subject to repeated trauma. Distribution of lichen sclerosus along the lines of Blaschko was described in an extragenital case.
Skin color is white, often with a shiny (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) porcelain appearance. Telangiectases and follicular plugs may be seen
.
Causes
The cause of lichen sclerosus is unknown. Over the years, a number of etiologies have been proposed. Several studies have linked borrelial or other infections with lichen sclerosus,5 yet other studies have disputed this. This concept has reemerged with European reports demonstrating Borrelia more readily in lichen sclerosus cases using “focus-floating microscopy” than conventional histology.6 Genetic and autoimmune factors have been explored without identification of consistent, reproducible patterns, although autoantibodies to ECM1 have now been reported by several independent authors. Increased circulating autoantibodies may be as high as 28%, comparable to the rate seen in bullous lichen planus.7
Local irritation seems to play (http://javascript%3Cb%3E%3C/b%3E:void%280%29;) a role in some cases, but the sequence of events that leads to the altered fibroblast function, microvascular changes, and hyaluronic acid accumulation in the upper dermis continues to be researched. A lichen sclerosus relative risk factor of 2.5 was seen in premenopausal women placed on oral contraceptives, which, once again, brings up an altered hormonal axis as a possible contributory factor.
mn2ool