Lichen Planus

Epidemiology and Etiology

Epidemiology

• Lichen planus (LP) affects < 1% of the population in the United States.
• Can occur at any age, but most commonly found in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship 30–60 years of age
• Rare in children

Etiology

• Unknown
• Associated risk factors: 
  • Genetic predisposition: ↑ frequency of human leukocyte antigen Antigen Substances that are recognized by the immune system and induce an immune reaction. Vaccination B7 (HLA-B7), HLA-DR1, and HLA-DR10 in those affected 
  • Hepatitis C Hepatitis C Hepatitis C is an infection of the liver caused by the hepatitis C virus (HCV). The infection can be transmitted through infectious blood or body fluids and may be transmitted during childbirth or through IV drug use or sexual intercourse. Hepatitis C virus can cause both acute and chronic hepatitis, ranging from a mild to a serious, lifelong illness including liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis C Virus virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology infection
  • Drug exposure:
    • Angiotensin-converting enzyme (ACE) inhibitors 
    • Beta-blockers Beta-blockers Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety. Class 2 Antiarrhythmic Drugs (Beta Blockers)
    • Methyldopa
    • Quinidine Quinidine An optical isomer of quinine, extracted from the bark of the cinchona tree and similar plant species. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. It prolongs cellular action potentials, and decreases automaticity. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission. Class 1 Antiarrhythmic Drugs (Sodium Channel Blockers)
    • Chloroquine Chloroquine The prototypical antimalarial agent with a mechanism that is not well understood. It has also been used to treat rheumatoid arthritis, systemic lupus erythematosus, and in the systemic therapy of amebic liver abscesses. Antimalarial Drugs 
    • Hydroxychloroquine Hydroxychloroquine A chemotherapeutic agent that acts against erythrocytic forms of malarial parasites. Hydroxychloroquine appears to concentrate in food vacuoles of affected protozoa. It inhibits plasmodial heme polymerase. Immunosuppressants
    • Thiazide Thiazide Heterocyclic compounds with sulfur and nitrogen in the ring. This term commonly refers to the benzothiadiazines that inhibit sodium-potassium-chloride symporters and are used as diuretics. Hyponatremia diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication
    • Gold salts
  • Primary biliary cirrhosis Biliary cirrhosis Fibrosis of the hepatic parenchyma due to obstruction of bile flow (cholestasis) in the intrahepatic or extrahepatic bile ducts. Primary biliary cholangitis involves the destruction of small intrahepatic bile ducts and decreased bile secretion. Secondary biliary cholangitis is produced by prolonged obstruction of large intrahepatic or extrahepatic bile ducts from a variety of causes. Cystic Fibrosis
  • Human herpesvirus type 7
  • Mercury Mercury A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200. 59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to mercury poisoning. Because of its toxicity, the clinical use of mercury and mercurials is diminishing. Renal Tubular Acidosis (in dental amalgam)
  • Radiotherapy
• Psychogenic factors, such as anxiety Anxiety Feelings or emotions of dread, apprehension, and impending disaster but not disabling as with anxiety disorders. Generalized Anxiety Disorder, depression, and stress

Pathophysiology

• Proposed mechanism involves cell-mediated immunity Cell-mediated immunity Manifestations of the immune response which are mediated by antigen-sensitized T-lymphocytes via lymphokines or direct cytotoxicity. This takes place in the absence of circulating antibody or where antibody plays a subordinate role. Squamous Cell Carcinoma (SCC).
• Exposure to exogenous agent (drug, virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology, other risk factors) → alters epidermal self-antigens
• CD4+ and CD8+ (more predominant) lymphocytes Lymphocytes Lymphocytes are heterogeneous WBCs involved in immune response. Lymphocytes develop from the bone marrow, starting from hematopoietic stem cells (HSCs) and progressing to common lymphoid progenitors (CLPs). B and T lymphocytes and natural killer (NK) cells arise from the lineage. Lymphocytes: Histology are recruited to dermal-epidermal junction → lead a T-cell–mediated attack → apoptosis Apoptosis A regulated cell death mechanism characterized by distinctive morphologic changes in the nucleus and cytoplasm, including the endonucleolytic cleavage of genomic DNA, at regularly spaced, internucleosomal sites, I.e., DNA fragmentation. It is genetically-programmed and serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth. Ischemic Cell Damage of  keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions 
• Basal layer is injured → release melanin Melanin Insoluble polymers of tyrosine derivatives found in and causing darkness in skin (skin pigmentation), hair, and feathers providing protection against sunburn induced by sunlight. Carotenes contribute yellow and red coloration. Seborrheic Keratosis into dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions → hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi
• Interaction of T lymphocytes T lymphocytes Lymphocytes responsible for cell-mediated immunity. Two types have been identified – cytotoxic (t-lymphocytes, cytotoxic) and helper T-lymphocytes (t-lymphocytes, helper-inducer). They are formed when lymphocytes circulate through the thymus gland and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen. T cells: Types and Functions and basal keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions enhanced by:
  • Intercellular adhesion Adhesion The process whereby platelets adhere to something other than platelets, e.g., collagen; basement membrane; microfibrils; or other ‘foreign’ surfaces. Coagulation Studies molecule-1 (ICAM-1) upregulation by basal keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions 
  • Other cytokines Cytokines Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner. Adaptive Immune Response: interferon ( IFN IFN Interferon (IFN) is a cytokine with antiviral properties (it interferes with viral infections) and various roles in immunoregulation. The different types are type I IFN (IFN-ɑ and IFN-β), type II IFN (IFN-ɣ), and type III IFN (IFN-ƛ). Interferons)-gamma, tumor Tumor Inflammation necrosis Necrosis The death of cells in an organ or tissue due to disease, injury or failure of the blood supply. Ischemic Cell Damage factor ( TNF TNF Tumor necrosis factor (TNF) is a major cytokine, released primarily by macrophages in response to stimuli. The presence of microbial products and dead cells and injury are among the stimulating factors. This protein belongs to the TNF superfamily, a group of ligands and receptors performing functions in inflammatory response, morphogenesis, and cell proliferation. Tumor Necrosis Factor (TNF))-alpha, interleukin (IL)-1 alpha, IL-6, and IL-8

Clinical Presentation

Cutaneous LP

• Clinical features:
  • Primary lesions can be characterized by the 6 Ps PS Invasive Mechanical Ventilation:
    • Polygonal
    • Purple (violaceous)
    • Pruritic (often severe)
    • Planar Papules (flat-topped)
    • May coalesce into larger Plaques
  • Wickham’s striae: lace-like white lines/dots, can be seen on the surface of the lesions
  • Koebner phenomenon:
    • Development of lesions in previously healthy sites 
    • Due to trauma from scratching
  • Hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi occurs with healed lesions.
  • May be painful depending on location
• Distribution and location:
  • Symmetric and bilateral
  • Most commonly found on flexural surfaces of extremities (ankles and wrists) 
• Clinical course:
  • Most resolve within 1–2 years
  • May leave permanent hyperpigmented macules after active disease is cleared

Cutaneous variants by morphology

• Hypertrophic:
  • Lichen planus verrucosus
  • Most pruritic form; associated with residual scarring Scarring Inflammation
  • Affects the anterior distal lower extremities
• Annular Annular Dermatologic Examination:
  • Plaques with central clearing
• Bullous:
  • Vesicles Vesicles Female Genitourinary Examination or bullae Bullae Erythema Multiforme develop within existing lesions.
  • Legs usually affected
• Actinic:
  • Plaques develop in sun-exposed areas.
  • Seen in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship of Middle Eastern descent
• Pigmentosus:
  • Gray-brown or dark-brown patches Patches Vitiligo 
  • Located in sun-exposed areas
• Inverse:
  • Plaques develop in uncommon sites (axillae, inguinal creases, inframammary area, limb flexures).
• Atrophic:
  • Plaques are well-demarcated pale or violaceous papules with superficial atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation.

Oral LP

• Clinical features:
  • Can occur independently or with cutaneous LP
  • Can present as:
    • Wickham’s striae or reticular form (lacy, web-like white threads)
    • Atrophic lesions
    • Bullous lesions
    • Painful erosions Erosions Corneal Abrasions, Erosion, and Ulcers or ulcers (erosive mucosal lichen planus) that can lead to secondary Candida Candida Candida is a genus of dimorphic, opportunistic fungi. Candida albicans is part of the normal human flora and is the most common cause of candidiasis. The clinical presentation varies and can include localized mucocutaneous infections (e.g., oropharyngeal, esophageal, intertriginous, and vulvovaginal candidiasis) and invasive disease (e.g., candidemia, intraabdominal abscess, pericarditis, and meningitis). Candida/Candidiasis infection and/or loss of appetite due to pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways
• Location:
  • Most common in buccal mucosa Buccal mucosa Oral Cancer
  • Also affects alveolar mucosa and tongue Tongue The tongue, on the other hand, is a complex muscular structure that permits tasting and facilitates the process of mastication and communication. The blood supply of the tongue originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy
• Clinical course: a chronic form of LP
• Mucosal and paramucosal lesions, especially at oral and vulvar sites (but not cutaneous lesions) have an increased risk of squamous cell carcinoma Squamous cell carcinoma Cutaneous squamous cell carcinoma (cSCC) is caused by malignant proliferation of atypical keratinocytes. This condition is the 2nd most common skin malignancy and usually affects sun-exposed areas of fair-skinned patients. The cancer presents as a firm, erythematous, keratotic plaque or papule. Squamous Cell Carcinoma (SCC).

Genital LP

• More common in men; lesions are typically on the glans penis Glans Penis Penis: Anatomy.
• In women, vulva Vulva The vulva is the external genitalia of the female and includes the mons pubis, labia majora, labia minora, clitoris, vestibule, vestibular bulb, and greater vestibular glands. Vagina, Vulva, and Pelvic Floor: Anatomy and vagina Vagina The vagina is the female genital canal, extending from the vulva externally to the cervix uteri internally. The structures have sexual, reproductive, and urinary functions and a rich blood supply, mainly arising from the internal iliac artery. Vagina, Vulva, and Pelvic Floor: Anatomy are affected.
  • Associated with pruritus Pruritus An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief. Atopic Dermatitis (Eczema) and dyspareunia Dyspareunia Recurrent genital pain occurring during, before, or after sexual intercourse in either the male or the female. Primary Ovarian Insufficiency
  • Erosive lesions can be complicated by urethral stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS).
  • Increased risk of squamous cell carcinoma Squamous cell carcinoma Cutaneous squamous cell carcinoma (cSCC) is caused by malignant proliferation of atypical keratinocytes. This condition is the 2nd most common skin malignancy and usually affects sun-exposed areas of fair-skinned patients. The cancer presents as a firm, erythematous, keratotic plaque or papule. Squamous Cell Carcinoma (SCC)
• Clinical course: chronic or persistent

Other forms of LP

• Nail:
  • Can be minor dystrophy to total nail loss
  • Dorsal pterygium (raised wedge-shaped deformity Deformity Examination of the Upper Limbs of nailbed): most specific LP nail abnormality
• Lichen planopilaris:
  • LP of the scalp that leads to keratotic follicular papules
  • Affects women more than men
  • Can progress to scarring Scarring Inflammation alopecia Alopecia Alopecia is the loss of hair in areas anywhere on the body where hair normally grows. Alopecia may be defined as scarring or non-scarring, localized or diffuse, congenital or acquired, reversible or permanent, or confined to the scalp or universal; however, alopecia is usually classified using the 1st 3 factors. Alopecia if left untreated
• Esophageal:
  • Can be asymptomatic or present with dysphagia Dysphagia Dysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical. Dysphagia or odynophagia Odynophagia Epiglottitis
  • Endoscopic findings: pseudomembranes Pseudomembranes Raised yellow or off-white plaques up to 2 cm in diameter that form as a result of mucosal ulceration Pseudomembranous Colitis, friable and inflamed mucosa, submucosal papules, lacy-white plaques, erosions Erosions Corneal Abrasions, Erosion, and Ulcers
  • Can lead to esophageal stricture Stricture Primary Sclerosing Cholangitis
• Otic:
  • Affects external auditory canals and tympanic membranes
  • Presents with erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion, pruritus Pruritus An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief. Atopic Dermatitis (Eczema), and induration Induration Dermatologic Examination; but can cause persistent otorrhea Otorrhea Otitis Externa and hearing loss Hearing loss Hearing loss, also known as hearing impairment, is any degree of impairment in the ability to apprehend sound as determined by audiometry to be below normal hearing thresholds. Clinical presentation may occur at birth or as a gradual loss of hearing with age, including a short-term or sudden loss at any point. Hearing Loss

Diagnosis

History and clinical findings

• Review of medical history, medications, and risk factors ( hepatitis C Hepatitis C Hepatitis C is an infection of the liver caused by the hepatitis C virus (HCV). The infection can be transmitted through infectious blood or body fluids and may be transmitted during childbirth or through IV drug use or sexual intercourse. Hepatitis C virus can cause both acute and chronic hepatitis, ranging from a mild to a serious, lifelong illness including liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis C Virus)
• Physical examination of entire cutaneous surface (including the scalp, oral cavity, and external genitalia)

Mucocutaneous biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma

• Deep shave or punch biopsy Punch Biopsy Actinic Keratosis of the most prominent lesion 
• Histopathological findings include:
  • Hyperkeratosis Hyperkeratosis Ichthyosis Vulgaris ( hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation of the stratum corneum Stratum corneum Skin: Structure and Functions)
  • Civatte bodies (anucleate, necrotic hypereosinophilic keratinocytes Keratinocytes Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell. Skin: Structure and Functions) in the lower epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions
  • Wedge-shaped hypergranulosis ( hyperplasia Hyperplasia An increase in the number of cells in a tissue or organ without tumor formation. It differs from hypertrophy, which is an increase in bulk without an increase in the number of cells. Cellular Adaptation of the stratum granulosum Stratum granulosum Skin: Structure and Functions)
  • “Saw-tooth” rete ridges Rete Ridges Lentigo Maligna 
  • Vacuolar alteration of basal layer of epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions
  • Band-like Band-Like Tension Headaches lymphocytic infiltrate at the dermal–epidermal junction Dermal–Epidermal Junction Bullous Pemphigoid and Pemphigus Vulgaris

Other tests

• Dermoscopy Dermoscopy A noninvasive technique that enables direct microscopic examination of the surface and architecture of the skin. Seborrheic Keratosis: aids AIDS Chronic HIV infection and depletion of CD4 cells eventually results in acquired immunodeficiency syndrome (AIDS), which can be diagnosed by the presence of certain opportunistic diseases called AIDS-defining conditions. These conditions include a wide spectrum of bacterial, viral, fungal, and parasitic infections as well as several malignancies and generalized conditions. HIV Infection and AIDS in visualizing Wickham’s striae in cutaneous lesions
• Laboratory test(s): check for hepatitis C Hepatitis C Hepatitis C is an infection of the liver caused by the hepatitis C virus (HCV). The infection can be transmitted through infectious blood or body fluids and may be transmitted during childbirth or through IV drug use or sexual intercourse. Hepatitis C virus can cause both acute and chronic hepatitis, ranging from a mild to a serious, lifelong illness including liver cirrhosis and hepatocellular carcinoma (HCC). Hepatitis C Virus in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with risk factors

Management

Supportive therapy

• Reduce pruritus Pruritus An intense itching sensation that produces the urge to rub or scratch the skin to obtain relief. Atopic Dermatitis (Eczema) with antihistamines Antihistamines Antihistamines are drugs that target histamine receptors, particularly H1 and H2 receptors. H1 antagonists are competitive and reversible inhibitors of H1 receptors. First-generation antihistamines cross the blood-brain barrier and can cause sedation. Antihistamines ( hydroxyzine Hydroxyzine A histamine h1 receptor antagonist that is effective in the treatment of chronic urticaria, dermatitis, and histamine-mediated pruritus. Unlike its major metabolite cetirizine, it does cause drowsiness. It is also effective as an antiemetic, for relief of anxiety and tension, and as a sedative. Antihistamines) 
• Avoid dry skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions with the use of emollients Emollients Oleaginous substances used topically to soothe, soften or protect skin or mucous membranes. They are used also as vehicles for other dermatologic agents. Pityriasis Rosea

First-line pharmacologic therapy

• High-potency topical corticosteroids Corticosteroids Chorioretinitis:
  • For localized lesions including oral lesions
  • Risks: cutaneous atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation, striae, changes in pigmentation
  • Betamethasone Betamethasone A glucocorticoid given orally, parenterally, by local injection, by inhalation, or applied topically in the management of various disorders in which corticosteroids are indicated. Its lack of mineralocorticoid properties makes betamethasone particularly suitable for treating cerebral edema and congenital adrenal hyperplasia. Glucocorticoids or clobetasol Clobetasol A derivative of prednisolone with high glucocorticoid activity and low mineralocorticoid activity. Absorbed through the skin faster than fluocinonide, it is used topically in treatment of psoriasis but may cause marked adrenocortical suppression. Glucocorticoids cream/ointment twice daily
  • Reassess response in 2–3 weeks.
• Intralesional corticosteroids Intralesional Corticosteroids Hypertrophic and Keloid Scars:
  • For hypertrophic lesions
  • Risks: cutaneous atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation, changes in pigmentation
  • Triamcinolone Triamcinolone A glucocorticoid given, as the free alcohol or in esterified form, orally, intramuscularly, by local injection, by inhalation, or applied topically in the management of various disorders in which corticosteroids are indicated. Glucocorticoids injection

Second-line pharmacologic therapy

• Systemic corticosteroids Corticosteroids Chorioretinitis
  • For extensive disease
  • Prednisone Prednisone A synthetic anti-inflammatory glucocorticoid derived from cortisone. It is biologically inert and converted to prednisolone in the liver. Immunosuppressants 30–60 mg/day for 4–6 weeks, followed by taper
• Topical calcineurin inhibitors Calcineurin Inhibitors Compounds that inhibit or block the phosphatase activity of calcineurin. Immunosuppressants
  • Treatment option for genital LP, resistant oral LP
  • Pimecrolimus Pimecrolimus Immunosuppressants, tacrolimus Tacrolimus A macrolide isolated from the culture broth of a strain of streptomyces tsukubaensis that has strong immunosuppressive activity in vivo and prevents the activation of T-lymphocytes in response to antigenic or mitogenic stimulation in vitro. Immunosuppressants
• Phototherapy Phototherapy Treatment of disease by exposure to light, especially by variously concentrated light rays or specific wavelengths. Hyperbilirubinemia of the Newborn
  • Narrowband ultraviolet B (UVB) therapy: preferred
  • Psoralen Psoralen Melanoma plus ultraviolet A (PUVA)
• Oral retinoids Retinoids Retinol and derivatives of retinol that play an essential role in metabolic functioning of the retina, the growth of and differentiation of epithelial tissue, the growth of bone, reproduction, and the immune response. Dietary vitamin A is derived from a variety of carotenoids found in plants. It is enriched in the liver, egg yolks, and the fat component of dairy products. Fat-soluble Vitamins and their Deficiencies
  • Acitrecin 30 mg/day for 8 weeks
  • Side effects: hypertriglyceridemia Hypertriglyceridemia A condition of elevated levels of triglycerides in the blood. Lipid Disorders, visual changes, hair loss
  • Teratogenic (avoid pregnancy Pregnancy The status during which female mammals carry their developing young (embryos or fetuses) in utero before birth, beginning from fertilization to birth. Pregnancy: Diagnosis, Physiology, and Care up to 3 years after discontinuation)

Differential Diagnosis

• Irritant contact dermatitis Contact dermatitis A type of acute or chronic skin reaction in which sensitivity is manifested by reactivity to materials or substances coming in contact with the skin. It may involve allergic or non-allergic mechanisms. Male Genitourinary Examination: skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions condition that results from exposure to a physical or chemical irritant. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion, edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema, vesicles Vesicles Female Genitourinary Examination, and oozing that are limited to areas where the offending substance was present.
• Discoid lupus erythematosus Discoid Lupus Erythematosus Alopecia: a chronic autoimmune skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions condition characterized by erythematous scaly plaques that often result in inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation, scarring Scarring Inflammation, and atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation on the face, neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, ears, and scalp. The condition may occur with or without concurrent systemic lupus erythematosus Systemic lupus erythematosus Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus.
• Lichenoid drug eruption: the symmetric cutaneous eruption that appears as erythematous papules on the trunk and extremities after taking a drug. Wickham’s striae is usually not present. In most cases, the condition will spontaneously resolve with discontinuation of the offending drug.
• Eczema Eczema Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema) (seen in atopic dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema)): a chronic pruritic skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions condition commonly found in children. Eczema Eczema Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema) is associated with asthma Asthma Asthma is a chronic inflammatory respiratory condition characterized by bronchial hyperresponsiveness and airflow obstruction. The disease is believed to result from the complex interaction of host and environmental factors that increase disease predisposition, with inflammation causing symptoms and structural changes. Patients typically present with wheezing, cough, and dyspnea. Asthma. Lesions are dry, pruritic, red papules mainly located on the cheeks Cheeks The part of the face that is below the eye and to the side of the nose and mouth. Melasma or scalp (in infants) and flexural areas of extremities (older children). 
• Seborrheic dermatitis Dermatitis Any inflammation of the skin. Atopic Dermatitis (Eczema): a chronic inflammatory dermatosis characterized by the presence of greasy, red (inflamed) skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesions affecting the scalp (as dandruff Dandruff Excessive shedding of dry scaly material from the scalp in humans. Seborrheic Dermatitis), posterior aspect of the neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, and the forehead Forehead The part of the face above the eyes. Melasma. The condition is linked to increased sebum Sebum The oily substance secreted by sebaceous glands. It is composed of keratin, fat, and cellular debris. Infectious Folliculitis production and possible colonization Colonization Bacteriology of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions by fungi Fungi A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies. Mycology of the genus Malassezia Malassezia Malassezia is a lipophilic yeast commonly found on the skin surfaces of many animals, including humans. In the presence of certain environments or triggers, this fungus can cause pathologic diseases ranging from superficial skin conditions (tinea versicolor and dermatitis) to invasive disease (e.g., Malassezia folliculitis, catheter-associated fungemia, meningitis, and urinary tract infections). Malassezia Fungi.
• Pityriasis rosea Pityriasis rosea Pityriasis rosea is an acute, self-limited skin disease. The etiology is not known, and it commonly occurs in young adults. Patients initially present with a single, ovoid “herald patch.” This is followed by diffuse, pruritic, scaly, oval lesions over the trunk (often in a “Christmas tree” distribution on the back) and extremities. Pityriasis Rosea: skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions condition affecting mostly older children and young adults. Pityriasis rosea Pityriasis rosea Pityriasis rosea is an acute, self-limited skin disease. The etiology is not known, and it commonly occurs in young adults. Patients initially present with a single, ovoid “herald patch.” This is followed by diffuse, pruritic, scaly, oval lesions over the trunk (often in a “Christmas tree” distribution on the back) and extremities. Pityriasis Rosea begins with a single “herald” patch Patch Nonpalpable lesion > 1 cm in diameter Generalized and Localized Rashes on the chest, neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess, or back. This is followed by smaller pruritic salmon-colored oval plaques with scaling located on the trunk and extremities. The characteristic morphology is a “Christmas tree” pattern on the back.
• Plaque Plaque Primary Skin Lesions psoriasis Psoriasis Psoriasis is a common T-cell-mediated inflammatory skin condition. The etiology is unknown, but is thought to be due to genetic inheritance and environmental triggers. There are 4 major subtypes, with the most common form being chronic plaque psoriasis. Psoriasis: lesions are characterized by well-demarcated, erythematous, symmetrically distributed plaques with overlying silver scales Scales Dry or greasy masses of keratin that represent thickened stratum corneum. Secondary Skin Lesions involving the scalp and extensor surfaces (elbows and knees). 
• Lichen simplex chronicus Lichen Simplex Chronicus A benign vulvar skin disorder characterized by hyperkeratosis (thickening of the skin) that occurs secondary to chronic vulvar irritation Benign Vulvar Conditions: a form of neurodermatitis caused by the itch-scratch cycle, leading to plaques and thickened skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions. Locations affected are areas accessible to scratching. Management includes potent topical steroids Steroids A group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. Benign Liver Tumors.