Fifth Stage Dermatology Dr. Hadaf – Lecture 71
Papulosquamous disordersLichen planus
• A common pruritic inflammatory disease of the skin &
/mucosa, nail & hair follicles that resemble lich en.
Pathogenesis• Thought to be an auto immune process with unknown
If the trigger is known then it is called lichenoid reaction
• Exposure to medicines, dyes, other chemicals as gold, antimalarials, antibiotics,
• Diseases such as hepatitis C
Epidemiology• Race: no racial predisposition
• Sex: Female to male ratio 3:2
• Age: more than 2/3 are 30 -60 years age, although
can occur at any age
Clinical presentation• 3 types of lesions
• 1- skin lesions
• 2- mouth lesions
• 3- other manifestations hair & nail lesions
Skin lesions• Characteristic; almost pathognomonic primary lesions:
small, violaceous, flat -topped, polygonal papules.
• Described as the 5 Ps disease:
• Pruritic, polygonal, purplish, plane, papules
• The surface is dry, shiny with whitish streaksor puncta called Wickham’s striae
• Sites: flexor wrists, med. thighs,
• trunk, shins, dorsal hands &
• Pos itive Koebner phenomenon
• prominent itching
M ucosaMucous membrane involvement: 50% of patients,
White lacy lines & dots, or small plaques
Usually inside cheeks, lips
Sometimes may be the sole manifestation (oral LP)
Genital mucosa may show same picture
70 -80% are females leading
to scarring alopecia
In 5 -10% of patients
May be the only manifestation esp. children
Longitudinal ridging, splitting , onychlysis, red lunula
Pterygium formation is characteristic of LP
Actinic lichen planusmostly middle east, sun exposed skin, in spring or
Adolescents & young adults
Face is target organ; forehead, cheeks, & lips
Annular, hyperpigmented plaques with hypopigmented
margin, & minimal itching
Diagnosis• 1- Clinical
• 2- histopathology
PrognosisIndividual lesions may las t months
The disease itself may last for 1 year
Hyperpigmentation usually follow resolution
Recurrence rate is 1 in 6
TreatmentMay be difficult
1)Limited lesions by superpotent topical or intralesional steroids
2)Indications of systemic steroids:
painful erosive oral lesions.
3)phototherpy: PUVA+ narrow -band UVB
4)Retinoids: in hypertrophic types
5) Antihistamines to relieve itching
Pityriasis roseaMild inflammatory exanthem characterized by pinkish, macular & papular lesions;
begin as discrete, then
EpidemiologyMainly children & young adults.
More in spring & autumn
W omen more than men
Herpes virus 6 & 7 implicated in etiology
Not contagious, 2% recurrence rate
Begin with herald patchwhich is larger, redder, more
scaly than remaining rash ;
Which consist of oval or
circinate patches covered with dry, crinkled, su rface,
desquamates leaving a collarette scale
Mainly trunk, extremities, neck
Inverted Christmas tree pattern
Mild pruritus & constitutional symptoms
Prognosis• Last 6 -8 weeks & r esolve spontaneously
• Sometimes they leave post inflammatory hyperpigmentation
TreatmentMost cases no treatment is required
To shorten the course or decrease itching:
1- UVB in erythema doses
2-Corticosteroids are the standard therapy
4-Emollients to relieve dryness & irritation
5-Erythromycine 250mg q.d.s for 2 weeks
REACTIVE ERYTHEMAERYTHEMA MULTIFORMI
A reaction pattern of multiform erythematous lesions.
ETIOLOGY1-Viral: preceding oral herpes 1 -2 weeks previously, also
orf, mycoplasma, hepatitis A,B,C.
2-bacterial, fungal, & parasit ic infection.
3-Drugs: sulfa, NSAID, anticonvulsants, & others
5-Malignancy or its treatment with radiotherapy
Start as sharply marginated, erythematous macule.Become raised edematous papules over 24 -48 hours.
A ring of erythema forms around the periphery, with flatter, purpuric dusky center,
giving” target lesions” of 3 zones
Bilateral, symmetrical, & acral distributionMostly starting on dorsa of hand s
Sites of predilection are extensor limbs, face, elbows, knees, palms & soles
Steven johnson syndromea severe variant with bullous lesions, fever & extensive mucosal involvement.
May be complicated by:
Treatm entMost cases are self -limited with symptomatic treatment.
Remove precipitating factors.
Recurrent HHV infection may be prevented by oral acyclovir 200mg 3 -5 times/day.
Steven -Johnson may require aggressive treatment: I.V. gamma globuline, good nu trition,
fluid & electrolyte balance, prevent secondary infection,+ high dose short course
systemic steroids & good nursing care for eyes & mouth.
Erythema nodosumInflammation of subcutaneous fat (panniculitis), elicited by many factors:
1) Bacterial infection: as T.B, strept., bruce lla, leprosy, yersinia.
2) viral, mycoplasma, rickettsia,& chlamydia
3)Fungal as coccidiomycosis
4)malignancy, sarcoidosis, ulcerative colitis, Behcet disease
5)drugs: sulfa & oral contraceptives.
Clinical featuresCharacteristic lesion is a tender red nodule , alone or
grouped on shins or forearms.
Other a reas as thighs, face, breast.
Bilateral, symmetrical lesions.
Mostly in young adult women
Acute onset, frequently with constitutional symptomsResolve within few days leaving bruise like
The whole course last 6 -8 weeks
D iagnosisThorough history
Chest x -ray
TreatmentSimple consisting of bed rest, NSAID as aspirin, indomethacin, ibuprofen
Systemic steroids not used
Potassium iodide in a dose of 400 -900 mg/day but not for more than 6 months