Lichen planus
At a Glance
Lichen planus is a chronic inflammatory condition that affects the skin, mucous membranes, hair, and nails, causing itchy rashes or painful sores due to an abnormal immune response.
This condition most commonly affects middle-aged adults between 30 and 60 years old and is estimated to affect approximately 1% to 2% of the global population.
While cutaneous lichen planus is often acute and self-limiting, the condition is considered manageable and can become chronic, particularly when it affects the mouth or genitals.
The outlook is generally favorable as most skin cases resolve on their own within a year or two, although the condition can significantly impact quality of life due to itching or pain and oral cases may persist for years.
How It Affects You
Lichen planus is a chronic inflammatory condition that causes swelling and irritation in the skin, hair, nails, and mucous membranes. It typically manifests as a rash or lesions that vary in appearance depending on the affected area. Common effects on the body include:
- Purplish, itchy, flat-topped bumps on the skin, most often on the wrists and ankles.
- Lacy white patches or painful sores inside the mouth or on the lips.
- Pain, itching, or discomfort in the genital area.
Causes and Risk Factors
Causes and Triggers
Lichen planus is an autoimmune-like condition where the body's immune system mistakenly attacks cells of the skin or mucous membranes. While the exact cause of this immune reaction is often unknown (idiopathic), several factors are known to trigger the condition in some people. It is not an infection and cannot be passed from person to person. Potential triggers and contributing factors include:
- Viral Infections: There is a statistical link between lichen planus and Hepatitis C infection, though not everyone with the virus develops the condition.
- Medications: Certain drugs can trigger a reaction that looks like lichen planus, including painkillers (NSAIDs), medications for high blood pressure (ACE inhibitors, beta-blockers), diuretics, and antimalarial drugs.
- Allergens: In rare cases, contact with chemicals or metals, such as mercury in older dental fillings, can trigger oral lichen planus.
- Stress: Emotional or physical stress is often reported as a factor that can worsen symptoms or trigger flare-ups.
- Genetics: While not directly inherited, a genetic predisposition may make some individuals more susceptible to developing the condition.
Prevention
There is no known way to prevent lichen planus from developing primarily. However, once diagnosed, patients can take steps to reduce the risk of flare-ups or worsening symptoms. Strategies include avoiding known triggers such as specific medications (under doctor supervision) or injury to the skin, as the rash often appears in areas of trauma (the Koebner phenomenon). Maintaining good oral hygiene and avoiding smoking can help manage oral lichen planus and reduce the risk of complications.
Diagnosis, Signs, and Symptoms
Signs and Symptoms
The symptoms of lichen planus vary significantly depending on the part of the body affected. The condition is often described by the "6 Ps": planar (flat-topped), purple, polygonal, pruritic (itchy), papules (bumps), and plaques. Clinically meaningful symptoms include:
- Skin: Purplish, flat bumps that are often very itchy. These lesions may have fine white lines on their surface, known as Wickham striae. They commonly appear on the wrists, ankles, and lower back. After the rash heals, it often leaves dark brown discoloration that can last for months.
- Mouth (Oral Lichen Planus): Lacy white patches on the inside of the cheeks or tongue are common. In erosive forms, bright red, painful sores or ulcers can develop, making eating difficult.
- Nails: Thinning, ridges, splitting, or grooving of the nails. In severe cases, the nail may be temporarily or permanently lost.
- Scalp (Lichen Planopilaris): Redness, irritation, and tiny bumps around hair follicles, which can lead to scarring and permanent hair loss.
- Genitals: Bright red, raw patches or painful sores that can cause discomfort during daily activities or intercourse.
Diagnostic Tests
Clinicians often identify lichen planus through a physical examination, looking for the characteristic flat-topped bumps and white lacy patterns. To confirm the diagnosis, the following may be used:
- Biopsy: A small sample of skin or mucous membrane is removed and examined under a microscope to look for specific patterns of inflammation and cell damage.
- Hepatitis C Testing: Because of the association between the two conditions, doctors may order a blood test to check for Hepatitis C.
- Allergy Testing: If an allergic reaction to a dental material or substance is suspected, patch testing may be recommended.
Treatment and Management
Medications and Therapies
Treatment focuses on managing symptoms, speeding up healing, and reducing inflammation, as there is no medical cure that permanently eliminates the condition. Options include:
- Corticosteroids: High-potency topical creams or ointments are the first line of defense to reduce swelling and redness. In severe or widespread cases, oral steroid pills (like prednisone) or injections may be used for a short period.
- Antihistamines: Oral antihistamines can help relieve the intense itching associated with skin lesions.
- Phototherapy: Light therapy using ultraviolet B (UVB) light can be effective for clearing skin rashes, though it usually requires multiple sessions over several weeks.
- Immune-Modulating Drugs: For severe cases that do not respond to steroids, doctors may prescribe calcineurin inhibitors (topical creams) or systemic immunosuppressants (pills) to dampen the immune system's overreaction.
- Oral Retinoids: These Vitamin A derivatives are sometimes used for severe cases but require careful monitoring due to potential side effects.
Lifestyle and Self-Care
Managing lichen planus involves avoiding irritants and caring for the affected areas. Patients with oral lichen planus should maintain excellent oral hygiene, use mild toothpastes, and avoid spicy or acidic foods. For skin involvement, avoiding scratching is crucial, as trauma can create new lesions. Cool compresses and oatmeal baths can help soothe itching.
When to Seek Medical Care
Patients should see a doctor if they notice new, unexplained rashes or sores in the mouth or on the genitals. Seek medical attention if:
- Symptoms worsen despite treatment or do not improve after a few weeks.
- There are signs of infection, such as increased redness, pus, or fever.
- Sores in the mouth make it difficult to eat or drink.
- There is rapid hair loss or changes in the nails.
Severity and Prognosis
Severity and Course
The severity of lichen planus ranges from mild, annoying rashes to severe, painful erosions that interfere with daily function. The course of the disease depends largely on the location:
- Cutaneous (Skin) Lichen Planus: Typically clears up on its own within 6 to 18 months. However, it can recur in some people. After the rash heals, post-inflammatory hyperpigmentation (dark spots) often remains for a long time.
- Oral and Genital Lichen Planus: These forms are more likely to be chronic and can persist for years or even decades. They are often more difficult to treat and may go through periods of remission and flare-up.
Complications and Long-Term Effects
While lichen planus is not dangerous in itself, it can lead to complications.
- Scarring and Hair Loss: Lichen planopilaris (scalp involvement) destroys hair follicles, leading to permanent, scarring alopecia.
- Nail Damage: Severe nail involvement can lead to permanent deformity or loss of the nail plate.
- Cancer Risk: There is a small increased risk of developing squamous cell carcinoma (a type of skin cancer) in areas of long-standing erosive lichen planus, particularly in the mouth or on the vulva. Regular monitoring is recommended for these patients.
- Strictures: Chronic inflammation in the genital tract can lead to scarring and narrowing (strictures), which may cause functional problems.
Impact on Daily Life
Impact on Daily Activities
Living with lichen planus can be challenging. The intense itching of skin lesions can disrupt sleep and concentration. Oral lichen planus can make eating spicy, hot, or acidic foods painful, leading to dietary restrictions and potential weight loss. Genital lichen planus can cause significant pain and sexual dysfunction, impacting intimate relationships and emotional well-being. Coping involves stress management, as stress is a known trigger for flare-ups. Support groups and counseling can help patients manage the emotional toll of chronic symptoms.
Questions to Ask Your Healthcare Provider
- What type of lichen planus do I have, and what is the expected course?
- Is my condition related to any medications I am currently taking?
- Do I need to be tested for Hepatitis C?
- What specific changes should I make to my diet or oral hygiene routine?
- What are the side effects of the prescribed treatments?
- How often do I need follow-up appointments to monitor for complications like skin cancer?
- What should I do if my symptoms suddenly get worse?
Common Questions and Answers
Q: Is lichen planus contagious?
A: No, lichen planus is not an infection. You cannot catch it from someone else, and you cannot spread it to others through contact.
Q: Is lichen planus a form of cancer?
A: No, it is not cancer. However, long-standing erosive lichen planus in the mouth or genitals carries a small increased risk of developing into squamous cell carcinoma, so regular check-ups are important.
Q: Can diet cure lichen planus?
A: There is no specific diet that cures the condition. However, people with oral lichen planus often find relief by avoiding spicy, acidic, crunchy, or hot foods that irritate the sores.
Q: Will the dark spots on my skin go away?
A: The dark spots (hyperpigmentation) that remain after the rash heals usually fade over time, but this process can take months or even years. Sun protection may help prevent them from getting darker.
Q: Can I inherit lichen planus from my parents?
A: Lichen planus is not directly inherited like eye color, but some genetic factors may make you more likely to develop it. It occasionally runs in families, but this is rare.