Lichen planus (L43)
The ICD-10 code L43 identifies lichen planus, a distinct inflammatory skin condition affecting various body parts. This group of codes is specifically used to document different forms and manifestations of lichen planus, ranging from typical cases to specialized variants like hypertrophic, bullous, or drug-related types.
The ICD-10 code for lichen planus (L43) covers the general diagnosis, while subcodes address particular presentations. For example, L43.0 refers to hypertrophic lichen planus, including thickened eruptions commonly on the vulva or oral regions. L43.1 denotes bullous lichen planus, characterized by blister formation. Drug-induced lichenoid reactions, which mimic classic lichen planus but are caused by medications, fall under L43.2. Other specified types, including ulcerative, annular, or pigmentary variants, are captured by L43.8. When the lichen planus form is unspecified or unclear, L43.9 is applied. These codes help medical coders accurately identify the exact clinical form, such as “oral lichenoid reaction” or “genital lichen planus,” ensuring precise documentation and treatment tracking.
Instructional Notations
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- lichen planopilaris L66.1
Clinical Terms
The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.
Lichen Planus
An inflammatory, pruritic disease of the skin and mucous membranes, which can be either generalized or localized. It is characterized by distinctive purplish, flat-topped papules having a predilection for the trunk and flexor surfaces. The lesions may be discrete or coalesce to form plaques. Histologically, there is a saw-tooth pattern of epidermal hyperplasia and vacuolar alteration of the basal layer of the epidermis along with an intense upper dermal inflammatory infiltrate composed predominantly of T-cells. Etiology is unknown.
Lichen Planus, Oral
Oral lesions accompanying cutaneous lichen planus or often occurring alone. The buccal mucosa, lips, gingivae, floor of the mouth, and palate are usually affected (in a descending order of frequency). Typically, oral lesions consist of radiating white or gray, velvety, threadlike lines, arranged in a reticular pattern, at the intersection of which there may be minute, white, elevated dots or streaks (Wickham's striae). (Jablonski, Illustrated Dictionary of Dentistry)
Onycholysis
Separation of nail plate from the underlying nail bed. It can be a sign of skin disease, infection (such as ONYCHOMYCOSIS) or tissue injury.
Onychomycosis
A fungal infection of the nail, usually caused by DERMATOPHYTES; YEASTS; or nondermatophyte MOLDS.
