Figure 2Click here to enlarge imageLevothyroxine (Synthroid)Fluticasone (Flonase)Multivitamin supplementsClinical impressions: The patient may have gingivitis, but it appears she has multiple complaints that may be all linked together, such as the skin lesions, vaginal yeast infections, and the ulcerative oral condition.Diagnosis: Lichen planus was confirmed through biopsy and immunofluorescence.Etiology: Lichen planus is a cell-mediated immune response affecting approximately 2 percent of the population. Although the disorder may occur in all age groups, women over age 50 are the most affected. The etiology is not completely understood, but genetics and immunity may be involved.Method of transmission: There is no contagion factor. This is a concern for most patients, and they should be told that it is not contagious. The patient will need reassurance that a partner or family member will not be infected by lichen planus.Pathogenesis: Lichen planus is a chronic mucocutaneous disorder. T-lymphocytes are recruited to the skin or oral mucosa where they produce damage to the surface epithelium. While the reaction suggests that the body is reacting to an antigen within the surface epithelium, to date the specific antigen has not been identified. While some authorities consider lichen planus to be an autoimmune disorder, until the antigen(s) is identified, some believe it is premature to consider lichen planus an autoimmune disease.Perioral and intraoral characteristics: Lichen planus may occur in six different patterns: reticular, plaque, erosive, bullous, atrophic, and papular. Generally, most clinicians classify the lesions as erosive or reticular patterns. Lichen planus may affect any lining mucosa including the eyes, lips, and esophageal regions.Extraoral characteristics: Lichen planus may affect any skin surface and external skin lesions are exhibited in up to 45 percent of reported cases. Women who have frequent vaginal yeast infections may have vaginal lichen planus and should be referred to a gynecologist to be evaluated, if they do have oral lichen planus. Often, the connection of oral and vaginal lesions is missed by both the dentist and the gynecologist and should be fully evaluated. Men may also have penile lichen planus. External skin lesions can be severe and require referral to a dermatologist in a team approach. Some patients suffer from full body lesions exhibiting purple, pruritic, and polygonal patches. Distinguishing characteristics: The reticular pattern of lichen planus is characterized by a lacy web-like white pattern called Wickham’s Striae. The name lichen is derived from the lichen plant that has a mossy, web-like appearance and is often seen growing on rocks.