lichen planus and lichenoid lesions

Question 1

describe lichen planus (what, demographic, factors)

Answer 1

• chronic mucocutaneous disease of unknown aetiology, cell-mediated immunological
• 30-60yo (older), female or ≥5yo
• factors = stress, genetics, Koebner phenomenon, systemic associations (HCV, thyroid, GvsHD, autoimmunity)

Question 2

phenotypes of lichen planus (6)

Answer 2

• reticular
• papular
• plaque-type
• erosive
• atrophic/erythematous
• bullous (rare)

Question 3

lichen planus demographic

Answer 3

middle-aged females (30-60yo) or ≥5yo

Question 4

malignancy transformation rate of lichen planus

Answer 4

<1%

Question 5

signs and symptoms of lichen planus (5)

Answer 5

• itchy purple papules (wrist flexor, lumbar, lower legs, genitals)
• VVG syndrome
  orally: relapse and remission
• bilateral symmetrical lesions on buccal/labial mucosa, tongue, gingiva
• desquamative gingivitis
• post-inflammatory pigmentation, no scarring

Question 6

describe VVG syndrome (2)

Answer 6

• variant of mucosal LP
• erosions and desquamation of the vulva, vagina and gingiva

Question 7

what are common and uncommon oral areas for LP lesions?

Answer 7

common = buccal/labial mucosa, tongue, gingiva
uncommon = fom, palate, upper lip

Question 8

typical histopathology of lichen planus (4)

Answer 8

• hyperkeratosis (para) and acanthosis with epithelial atrophy in other areas
• loss of rete pegs or “saw tooth” pattern
• dense band of lymphocytic infiltrate
• liquefaction degeneration and BM widening

Question 9

management of lichen planus (3)

Answer 9

1. exclude OLL/diagnosis
2. asymptomatic = reassurance
3. symptomatic:
   - mild = topical steroids (prednisolone, bethamethasone, fluticasone, calcineurin inhibitors)
   - mod/severe = + systemic drugs

Question 10

examples of systemic drugs for lichen planus management (5)

Answer 10

• corticosteroids
• hydroxychloroquine
• azathioprine
• methotrexate
• mycophenolate

Question 11

describe oral lichenoid reaction (what, cause, histology)

Answer 11

• type IV hypersensitivity reaction or cell-mediated immune reaction
• caused by a drug or agent in the mouth
• similar histology to LP

Question 12

malignancy transformation rate of OLL

Answer 12

2.1%

Question 13

examples of substances that can cause OLL (3)

Answer 13

1. DRUGS:
   - antihypertensives (ACEi, B blocker) and hypoglycaemics (biguanide, sulphonylurea)
   - gold injections, antimalarials, NSAIDs (naproxen)
2. toothpaste, MW, chewing gum, lip cosmetics, denture fixative
3. methyl methacrylate, nickel, amalgam, metals

Question 14

signs and symptoms of OLL (4)

Answer 14

• unilateral LP-like lesion
• erythema, vesicles/ulceration
• loss of lingual papillae
• resolution on removal of causative factor

Question 15

OLL management (2)

Answer 15

1. monitor +/- biopsy and patch testing
2. remove causative factor if known

Question 16

give 2 main differences between OLL and LP

Answer 16

• LP bilateral and symmetrical, OLL unilateral
• LP no causative factor, OLL with causative factor and resolution on withdrawal