<unk>  affecting the lower lip Although<unk>  can present with a variety of lesions, the most common presentation is as a well defined area of purple-coloured, itchy, flat-topped papules with interspersed lacy white lines (Wickham's striae). This description is known as the characteristic "6 Ps" of<unk> : planar (flat-topped), purple, polygonal, pruritic, papules, and plaques. This rash, after regressing, is likely to leave an area of hyperpigmentation that slowly fades. That said, a variety of other lesions can also occur. Skin Cutaneous<unk>  on the shin<unk>  involving the nails Variants of cutaneous<unk>  are distinguished based upon the appearance of the lesions and/or their distribution. Lesions can affect the: * Extremities (face, dorsal hands, arms, and nape of neck). This is more common in Middle Eastern countries in spring and summer, where sunlight appears to have a precipitating effect. * Palms and soles * Intertriginous areas of the skin. This is also known as "inverse<unk> ." * Nails characterized by irregular longitudinal grooving and ridging of the nail plate, thinning of the nail plate, pterygium formation, shedding of the nail plate with atrophy of the nail bed, subungual keratosis, longitudinal erthronychia (red streaks), and subungual hyperpigmentation. A sand-papered appearance is present in around 10% of individuals with nail<unk> . * Hair and scalp. The scalp is rarely affected by a condition known as lichen planopilaris, acuminatus, follicular<unk> , and peripilaris, characterised by violaceous, adherent follicular scale with progressive scarring alopecia. While<unk>  and lichen planopilaris may occur together, aside from sharing the term 'lichen' and revealing inflammation on skin biopsy, there is neither established data on their co-occurrence nor data to suggest a common etiology. Lichen planopilaris is considered an orphan disease with no definitive prevalence data and no proven effective treatments. Other variants may include: *<unk>  pemphigoides characterized by the development of tense blisters atop lesions of<unk>  or the development vesicles de novo on uninvolved skin. * Keratosis lichenoides chronica (also known as "Nekam's disease") is a rare dermatosis characterized by violaceous papular and nodular lesions, often arranged in a linear or reticulate pattern on the dorsal hands and feet, extremities, and buttock, and some cases manifest by seborrheic dermatitis-like eruption on the scalp and face; also palmo plantar keratosis has been reported. * Lichenoid keratoses (also known as "benign lichenoid keratosis," and "Solitary<unk> ") is a cutaneous condition characterized by brown to red scaling maculopapules, found on sun-exposed skin of extremities. Restated, this is a cutaneous condition usually characterized by a solitary dusky-red to violaceous papular skin lesion. * Lichenoid dermatitis represents a wide range of cutaneous disorders characterized by<unk> -like skin lesions. Mucous membranes<unk>  on the lips and the lateral border of the tongue<unk>  affecting mucosal surfaces may have one lesion or be multifocal. Examples of<unk>  affecting mucosal surfaces include: * Esophageal<unk> , affecting the esophageal mucosa. This can present with difficulty or pain when swallowing due to oesophageal inflammation, or as the development of an esophageal stricture. It has also been hypothesized that it is a precursor to squamous cell carcinoma of the esophagus. * Genital<unk> , which may cause lesions on the glans penis or skin of the scrotum in males, and the vulva or vagina in females. Symptoms may include lower urinary tract symptoms associated with stenosis of the urethra, painful sexual intercourse, and itching. In females, Vulvovaginal-gingival syndrome, is severe and distinct variant affecting the vulva, vagina, and gums, with complications including scarring, vaginal stricture formation, or vulva destruction. The corresponding syndrome in males, affecting the glans penis and gums, is the peno-gingival syndrome. It is associated with HLA-DQB1. Mouth Classic white striations of non-erosive<unk>  in the left buccal mucosa (left cheek) Oral<unk>  (also termed oral mucosal<unk> , is a form of mucosal<unk> , where<unk>  involves the oral mucosa, the lining of the mouth. This may occur in combination with other variants of<unk> . Six clinical forms of oral<unk>  (OLP) are recognized: + Lesion morphology Description Reticular The most common presentation of oral<unk>  (OLP), is characterised by the net-like or spider web-like appearance of lacy white lines, oral variants of Wickham's straiae. This is usually asymptomatic. Reticular OLP may eventually progress to the more severe subtypes such as the erosive form. Erosive/ Ulcerative The second most common form and the most advance form of oral<unk> , is characterised by oral ulcers presenting with persistent, irregular areas of redness, ulcerations and erosions covered with a yellow slough. This can occur in one or more areas of the mouth. In 25% of people with erosive oral<unk> , the gums are involved, described as desquamative gingivitis (a condition not unique to<unk> . This may be the initial or only sign of the condition. Involvement of the dorsum of the tongue might cause an altered sense of taste (dysgeusia). Papular This form is characterized by small white pinpoint papules that are asymptomatic. Hence, they can be easily missed during a routine checkup. It is referred to as the initial and transient phase of OLP. Plaque-like Large, homogenous white patches are characteristic of this form which may resemble leukoplakia. This form is more prevalent in tobacco smokers. Atrophic This form is a common presentation that has similarities to the erosive form. It has a more prominent atrophic lesion on a background of erythema with radiating white striae at the margins. Atrophic oral<unk>  may also manifest as desquamative gingivitis. Bullous Rare form of OLP characterized by fluid-filled vesicles ranging in size from 1 to 2 mm to several cm in diameter. The vesicles or bullae appear white or gray-purple in color and are fluctuant. The fluid in the vesicles are usually clear but may be hemorrhagic or purulent upon secondary infection. These rupture easily and they leave an ulcerated, painful surface. These types often coexist in the same individual. Oral<unk>  (OLP) tends to present bilaterally as mostly white lesions on the inner cheek, although any mucosal site in the mouth may be involved. Other sites, in decreasing order of frequency, may include the tongue, lips, gingivae, floor of the mouth, and very rarely, the palate. Generally, oral<unk>  tends not to cause any discomfort or pain, although some people may experience soreness when eating or drinking acidic or spicy foodstuffs or beverages. When symptoms arise, they are most commonly associated with the atrophic and ulcerative subtypes. These symptoms can include a burning sensation to severe pain. They may also experience mucosal bleeding in response to mild trauma, such as toothbrushing. Additionally, the Koebner phenomenon (the development of new lesions at sites of trauma) is not only present in cutaneous<unk>  (CLP) but can also occur in the setting of OLP. Residual postinflammatory hyperpigmentation has been reported in association with OLP, manifesting as brown to black pigmentation on the oral mucosa and may most likely occur in dark-skinned individuals. OLP may occur as a sole manifestation of the disease or in conjunction with other clinical manifestations of<unk> , including cutaneous<unk> , genital<unk> , nail<unk> , and lichen planopilaris (scalp<unk> .
Lichen planus
Geographic tongue
Lichen nitidus
Leukoplakia
Lichen simplex chronicus
Lichen myxedematosus
Lichen sclerosus
Tinea barbae