32 - Lichen Planus Flashcards
Four Ps
- Purple
- Polygonal
- Pruritic
- Papules
_____ immunity plays a major role in lichen planus and _____ immunity is most likely a secondary response
Cell-mediated
Humoral
Three stages in the pathogenesis of lichen planus
- Antigen recognition
- Lymphocyte activation
- Keratinocyte apoptosis
- Resolution*
Effector cell of lichen planus
CD8-positive T-cytotoxic cells
Contact sensitizers such as _____ could act as haptens and elicit an immunologic response in lichen planus
Metals
Fundamentally involved in the upregulation of cellular adhesion molecules and subsequent migration of lymphocytes to the dermal-epidermal junction
IFN-gamma
Gene expression profiling of lichen planus, identified the expression of the _____ as the most specific marker
for lichen planus
CXCR-3 ligand, CXCL-9
Peak onset of lichen planus between _____ years
55 and 74
The age of onset of lichen planus is earlier in
Women
HLA-_____ is more common in patients with oral lichen planus alone
B8
HLA-_____ is more common in patients with cutaneous lichen planus alone
Bw35
Fine, white and adherent reticulate scale highly characteristic of lichen planus
Wickham striae
Wickham striae are more easily visualized with
Dermoscopy
Histologic findings of Wickham striae
Orthokeratosis, epidermal thickening, increased granular layer
Dull red-violet color of lichen planus correlates with _____ histologically
Vascular dilatation and pigment incontinence
Most common areas of involvement of lichen planus
Flexural wrists
Arms
Legs
Involvement of the _____ and _____ are atypical for classic lichen planus
Face
Palms
The degree of pruritus appears to directly correlate with the extent of involvement except in
Hypertrophic lichen planus - often affects limited areas, such as the lower extremities, and is extremely pruritic
Annular lichen planus are more common on the
Penis
Scrotum
Actinic lichen planus is frequently _____ in shape
Annular
Type of lichen planus that is highly pruritic, refractory to treatment, and associated with relapse
Hypertrophic lichen planus
Hypertrophic lichen planus occurs most commonly on
Anterior shins
Interphalangeal joints
Some believe that this type of lichen planus occurs in late-stage resolved disease and is not a true variant of lichen planus
Atrophic lichen planus
Atrophic lichen planus is most common on the
Proximal lower extremity
Trunk
Occur secondary to an exuberant inflammatory response and an exaggerate Max-Joseph space
Vesiculobullous lichen planus
Lichen planus pemphigoides vs cesiculobullous lichen planus
Lichen planus pemphigoides has classic lesions of lichen planus separated from lesions of bullous pemphigoid and positive bullous pemphigoid antibodies and immunofluorescence
Vesiculovullous lichen planus is more common on the
Lower extremities
Erosive and ulcerative lichen planus is more common on the
Feet
Oral cavity
Follicular lichen planus occurs most commonly on the
Scalp
Three distinct variants of follicular lichen planus
Lichen planopilaris
Frontal fibrosing alopecia
Gram-Little- Piccardi-Lassueur syndrome (GLPLS)
Characterized clinically by pruritic, red-violet pseudo-tumoral facial and posterior auricular plaques with yellow cysts
Lichen planus follicularis tumidus
Lichen planus pigmentosus
and _____ have significant overlapping features and likely represent a phenotypic spectrum based on genetic and environmental factors
Ashy dermatosis or erythema dyschromicum perstans
Actinic lichen planus has a predilection for the
Face
Lesions of actinic lichen planus are (minimally/extremely) symptomatic
Minimally
Lichen planopilaris has a (male/female) predominance
Female
Classic lichen planopilaris affects the _____ scalp
Vertex
The most active lesions of lichen planopilaris are found
Within the hair-bearing areas at the edge of the alopecic patch
Characterized by progressive frontotemporal recession caused by inflammatory destruction of the hair follicles
Frontal fibrosing alopecia
Up to 75% of women with frontal fibrosing alopecia report concomitant loss of
Eyebrows
Frontal fibrosing alopecia is more common in
Postmenopausal women
Characterized by cicatricial alopecia of the scalp, nonscarring alopecia of the axilla and groin, and follicular papules on the trunk and extremities
Gram-Little- Piccardi-Lassueur syndrome (GLPLS)
End stage of follicular fibrosis caused by a primary inflammatory dermatosis; distinct pathologic features are absent
Pseudopelade of Brocq
Most common form of oral lichen planus
Reticular form
Most common site of involvement of reticular oral lichen planus
Buccal mucosa
Oral lichen planus that is most common on the tongue and is extremely painful
Erosive and ulcerative
Oral lichen planus is the most common cause of desquamative gingivitis, accounting for _____% of cases
75
Similar clinically and histologically to oral lichen planus; however, with an identifiable cause
Oral lichenoid reactions
Usually seen on the buccal mucosa adjacent to amalgam dental fillings; patch tests frequently show positive
reactions to mercury, gold, and other metals
Oral lichenoid reactions
Unique lichenoid eruption described on the tongues of individuals with HIV usually follows _____ intake
Zidovudine
Ketoconazole
Esophageal lichen planus most often affects the _____ and is most common in
Proximal esophagus
Middle-aged women
Y/N: Vulvar and vaginal lichen planus is often asymptomatic
Yes
In cases with severe oral and ocular disease and a
lichenoid infiltrate on biopsy, one should also consider
Paraneoplastic autoimmune multiorgan syndrome
Cicatricial pemphigoid
Three major forms of nail lichen planus
Classic nail lichen planus
20-nail dystrophy
Idiopathic atrophy of the nails
Pterygium or forward growth of the eponychia with adherence to the proximal nail plate is a classic finding in nail lichen planus involving the _____
Matrix
Y/N: Dorsal pterygium is a reversible process.
No
Characterized by an abrupt onset and rapidly progressive thinning of the nails with subsequent loss and scarring
Idiopathic atrophy of the nails
Inverse lichen planus vs lichen planus pigmentosus
Absence of involvement in sun-exposed areas in inverse lichen planus
Four patterns of palmoplantar lichen planus
Plaque type
Punctate
Diffuse keratoderma
Ulcerated
Absence of Wickham striae in this type of lichen planus
Palmoplantar
Lesions of palmoplantar lichen planus are commonly seen on the
Internal plantar arch
Thenar and hypothenar eminence
In palmoplantar lichen planus, involvement of the _____ is uncommon
Fingertips
Most lichenoid drug eruptions resolve in 3 to 4 months except
Gold-induced lichenoid drug eruption
Lichen planus pemphigoides vs concomitant lichen planus and bullous pemphigoid
Lichen planus pemphigoides is most common in younger individuals in the fourth to fifth decades of life
Characterized by lichenoid, keratotic papules and plaques in a seborrheic distribution with characteristic linear or reticulate pattern
Keratosis lichenoides chronica (Nekam disease)
Immune response in acute vs chronic GVHD
Acute: Th2
Chronic: Th1/Th17
Lichenoid GVHD vs lichen planus histologically
Lichenoid GVHD: satellite cell necrosis, plasna cells, eosinophils
Single, nonpruritic, brown to red, scaling, flat-topped plaque on sun-exposed skin of the extremities
Lichenoid keratosis
Differential diagnosis of lichenoid dermatitis
Dermatitis Drug eruption Lupus erythematosus Lichen planus Cutaneous T-cell lymphoma
Hepatitis infection associated with lichen planus
Hepatitis C
Found in up to 34% of patients with lichen planopilaris
Thyroid dysfunction, most commonly hypothyroidism
Seen in up to 16% of patients with oral lichen planus
Lichen sclerosus et atrophicus
Most common site for cancer in lichen planus
Tongue
Two major pathologic findings in lichen planus
Basal epidermal keratinocyte damage
Lichenoid-interface lymphocyte reaction
Features absent in the histopathology of lichen planus
Parakeratosis
Eosinophils
Multiple apoptotic cells seen at the DEJ in lichen planus
Colloid-hyaline (Civatte) bodies
Separation of the epidermis in small clefts in lichen planus
Max Joseph cleft
The initial inflammation in lichen planopilaris is at the level of
Isthmus and infundibulum
Histopathologically, hypertrophic lichen planus can be mistaken as
SCC
DIF criterion for lichen planus
Basement membrane zone and colloid bodies with one or more conjugate(s)
Biopsy site for cutaneous lichen planus
Proximal trunk with avoidance of the distal extremities
Biopsy site for lichen planopilaris
Dermoscopy: perifollicular erythema and scaling
Biopsy site for nail disease with trachyonychia and pitting
Matrix
Biopsy site for nail disease with chromonychia, nail plate fragmentation, splinter hemorrhage, onycholysis, and subungual debris
Nail bed
DIF for lichen planus has the highest sensitivity on
Mouth floor
Ventral side of tongue
Most cutaneous lichen planus resolves within
1-2 years
(Generalized/Localized) disease tends to resolve more quickly
Generalized
First line therapy for limited cutaneous lichen planus
High-potency topical corticosteroids
Second-line topical agent often used in conjunction with topical steroids in refractory cases of limited cutaneous lichen planus
Topical calcineurin inhibitors
First-line systemic agents for lichen planus
Oral corticosteroids
Third-line corticosteroid-sparing agent for lichen planus
Cyclosporine
Drugs that target lymphocytes more specificially
Methotrexate
Mycophenolate mofetil
Azathioprine
Drugs that target lymphocytes more specificially are of higher utility in
Refractory and ulcerative disease
Drugs acting indirectly on lymphocytes
Sulfasalazine
Metronidazole
Drugs acting on cellular differentiation
Acitretin
Drugs acting indirectly on lymphocytes are more effective for
Generalized disease
Drugs acting on cellular differentiation are more effective for
Hypertrophic disease
Y/N: Monotherapy with oral corticosteroids is the gold standard in the management of lichen planus.
No - Long-term monotherapy with oral corticosteroids is not recommended.
Has the highest level of evidence of efficacy for lichen planus
Sulfasalazine
Agranulocytosis and elevated liver function tests can occur with
Sulfasalazine
Often considered the first-line nonimmunosuppressive systemic agent
Metronidazole
Patients on metronidazole should be monitored for possible
Sensory peripheral neuropathy
Second-line agent in cutaneous lichen planus and first-line agent in actinic lichen planus
Hydroxychloroquine
Cornerstone of treatment in oral lichen planus
Good oral hygiene with regular professional dental cleanings
First-line therapy in oral lichen planus
Topical steroids
Common adverse event of topical calcineurin inhibitors
Transient burning
Preferred systemic therapies in oral lichen planus
Acitretin - antiproliferative effects
HCQ and MTX - less immunosuppressive agents
Preferred systemic therapy for oral erosive disease
MMF
Methotrexate
Preferred systemic therapy for noneroded and hyperkeratotic disease
Acitretin
High-potency topical corticosteroids have been shown to be ineffective in this type of lichen planus
Frontal fibrosing alopecia
Most commonly used and most effective drugs in frontal fibrosing alopecia
Finasteride or dutasteride