Skin and Mucosal Diseases part 2 Flashcards
(55 cards)
What is lichen planus?
- Common, chronic disease that affects skin and oral mucosa
- Immune mediated mucocutaneous disorder
- Medications may cause similar appearance: lichenoid mucositis
What are the clinical features of lichen planus?
- MC in middle-aged female adults
- Skin lesions: purple, pruritic, polygonal, papules (4-P’s)
- Often affect flexor surfaces of extremities
What are the clinical features of reticular type (most common) of lichen planus?
- Involves buccal mucosa bilaterally
- Interlacing white lines – Wickham striae
- Wax and wane
- Post-inflammatory melanosis
- Usually asymptomatic
What are the clinical features of erosive type of lichen planus?
- Atrophic, erythematous areas with central ulceration
- Patients often symptomatic
- Periphery bordered by fine, white radiating striae
- Atrophy and ulceration confined to gingiva: desquamative gingivitis
What are the two types of lichen planus?
- reticular type (most common)
- erosive type
How is lichen planus diganosed?
- Clinical, histopathology, direct immunofluorescence
- 10% Formalin vs Michels solution
What is the treatment for lichen planus?
- Reticular: usually asymptomatic, no tx needed
- Erosive: topical corticosteroids
lichen planus
reticular
lichen planus
erosive
What are the areas of dark purple of this histology of lichen planus?
inflammatory cells
What technique is used here and for what disease?
direct immunofluorescence
- lichen planus
What is erythema multiforme?
- Ulcerative mucocutaneous condition of uncertain etiology
- Likely an immune mediated process
- 50% of cases: precipitating cause – infections (ie: herpes simplex), medications (infrequently)
What are the clinical features of erythema multiforme?
- Often observed in young adults (20s and 30s)
- Prodromal symptoms: Fever, malaise, headache, cough
- Slightly elevated, round, dusky-red patches on skin
- May appear as concentric circular erythematous rings – target lesion
What are the clinical sites of erythema multiforme?
- Oral cavity: most frequently involved mucosal site
- Ocular, genitourinary, respiratory mucosa may be affected
— Severe ocular involvement: scarring (symblepharon formation) - Oral lesions: shallow erosions or ulcerations with irregular borders
- Lips, labial mucosa, buccal mucosa, tongue, FOM, soft palate
- Hemorrhagic crusting of the vermilion zone of lips
What are the types of erythema multiforme?
- Erythema multiforme minor: milder cases
— Skin lesions and 1 mucosal site (usually oral) - Erythema multiforme major: more severe
— Widespread skin lesions and 2 or more mucosal sites
What is the treatment for erythema multiforme?
- Usually self-limiting (2-6 weeks)
- Systemic or topical corticosteroids
erythema multiforme
bullseye/target lesion
erythema multiforme
What is Stevens-Johnson syndrome and toxic epidermal necrolysis?
- Severe blistering diseases triggered by drug exposure
- SJS: <10% skin and mucosal involvement
- TEN: >30% skin and mucosal involvement
What are the clinical features of stevens-johnson syndrome?
- SJS: usually seen in younger patients
- Initially present with flu-like symptoms
- After a few days, cutaneous lesions appear on trunk
- Erythematous macules
- Sloughing of the skin, flaccid bullae
- May have mucosal changes as well
What are the clinical features of toxic epidermal necrolysis?
- TEN: usually patients above 60 years
- Initially present with flu-like symptoms
- After a few days, cutaneous lesions appear on trunk
- Erythematous macules
- Sloughing of the skin, flaccid bullae
- May have mucosal changes as well
What is the treatment for Stevens-Johnson syndrome and toxic epidermal necrolysis?
- Identify, immediately discontinue offending drug
- Management in burn unit of hospital
- Mortality rate: SJS – 1-5% , TEN – 25-30%
Stevens-Johnson syndrome and toxic epidermal necrolysis
What is pemphigus vulgaris?
- Autoimmune disease
- Immune attack on desmosomes – intra-epithelial split
- 1-5 cases per million people