Lecturer Of
Dermatology & Venereology
Zagazig University
 It is a chronic proliferative
skin disease that affects about
1-2% of general population.
Genetic predisposition with triggering factors:
 Trauma: can elecit (koebner phenomenon).
 Weather: worse in winter.
 Endocrinal factors: It may improves with pregnancy
and exacerbate with puberty and menopause.
 Infection: steptococcal infection may be followed by
guttate psoriasis .
 Drugs: ß adrenergic blockers, NSAIDs and ACE
 Emotional stress.
 Alcohol and smoking.
 Parakeratosis (accelerated incomplete keratinization of horny
cells with retension of neuclei) with focal orthokeratosis.
Absent granular cell layer.
Regular acanthosis and elongation of club shaped rete ridges.
Suprapapillary thinning of epidermis.
Munro microabscesses formed of collected neutrophils in
stratum corneum or just beneath it.
Spongiform pustules in malpighian layer.
 Elongation and edema of dermal papillae.
 Dilated tortuous capillaries in the upper portion
of papillae.
 Perivascular
mononuclear and neutrophil
inflammatory infiltrate in upper dermis.
Clinical picture:
 The primary lesion is a salmon pink papule
covered with silvery scales. Papules may
enlarge or coalesce forming plaques.
 Sites: extensor surfaces of limbs, elbows,
knees, scalp, and nails.
Grattage test
 Scraping of psoriatic lesion with the edge of
a glass slide results in removal of the scales
layer after layer with accentuation of the
silvery appearance until a smooth glossy red
membrane is finally left. On scratching this
membrane pinpoint hemorrhages appear
(Auspitz's sign).
Morphological patterns
1-Punctate psoriasis (pin point size)
2-Guttate psoriasis (size of drops)
3-Discoid psoriasis (coin shaped)
4-Annular psoriasis (ring shaped lesions
produced by involution of center of the
5-Geographical psoriasis (curved patterns
produced on a large area as the back).
6-Linear psoriasis
Clinical varieties
- Flexural psoriasis: as in axillae and groins.
- Psoriasis of palms and soles: may be either;
Typical scaly plaques
Or thick, fissured plaques similar to hyperkeratotic eczema
Or pustular type
- Erythrodermic type: generalised erythema and scaling.
- Psoriasis of nails: pitting, yellowish discolouration, circular area of
discolouration (oil drop) transverse ridging, onycholysis (distal
separation), thickening, subungual hyperkeratosis.
- Arthropathic psoriasis.
- Psoriasis of scalp: not crossing the hair line (D D from seborrheic
- Pustular psoriasis: localised or generalized, the primary lesions
here is a sterile pustule.
Flexural psoriasis
Psoriasis of palms and soles:
Erythrodermic psoriasis:
Psoriasis of nails:
Psoriasis of scalp:
Pustular psoriasis:
 Epidermal keratinocyte hyperproliferation.
The transit time of epidermal cell maturation
from a basal cell to be a horny cell in normal
skin is about 26-28 days whereas in psoriatic
skin it is only 3-4 days.
 T-cell
mediated inflammatory
involving mainly Th1 cells.
Koebner phenomenon:
 It is development of isomorphic pathologic
lesions in the traumatized uninvolved skin of
patients who have psoriasis.
 Psoriasis, warts, lichen planus, vitiligo,
molluscum contagiosum and pityriasis rubra
pilaris (PRP).
A-Topical treatment
1-Tar :crude coal tar 2-5%.
2-Anthralin 0.1-1%.
3-Salicylic acid (3-5%) keratolytic remove scales.
4-Corticosteroids ointment.
triamcinolone acetonide in localised resistent
plaques but less effective in nail psoriaisis.
6-Calcipotriol ointment (vitamin D analogue). It
inhibits keratinocyte proliferation.
B-Systemic treatment
1-Methotrexate 2.5mg tab (5mg every 12 hour for 3 doses)
every week. It is indicated in erythrodermic psoriasis and
generalized pustular psoriasis. Liver function should be
2-Retinoids; etretinate: 1 mg/kg/day and acitretin 0.5-1
mg/kg/day in severe cases and erythrodermic psoriasis
3-Photochemotherapy (PUVA): psoralens 0.6 mg/kg 2 hours
before the exposure to UVA rays 2-3 times weekly
4- Phototherapy: narrowband UVB rays (NBUVB)
5-Cyclosporin A: immunosuppresive for severe cases 2.55mg/kg/day.
 Lichen planus is an itchy chronic
inflammatory disease which affects
skin and mucous membranes.
1-Genetic predisposition
3- Strong association with hepatitis C infection
4- Emotional stress
Clinical picture
 The primary lesion is a pruritic shiny violaceous flat topped
polygonal papule which retains the skin lines and shows
white streaks (wickham’s striae). These striae can be seen
well with a magnifying lens.
 It is commonly seen on wrist, back of hands, shin and ankles
in hypertrophic type, lumbar region, glans penis in annular
type and palms and soles.
 Mucous membrane lesions are very common (in 30-70% of
cases) and may occur alone without skin involvement.
 After disappearance of the lesions deep pigmentation is left
for several months
Clinical varieties:
1- Atrophic lichen planus; fading annualr or hypertrophic type.
2- Hypertrophic Lichen planus: deep violet rough papules over shin of tibia
and ankles.
3- Linear lichen planus.
4- Annular lichen planus (on glans penis).
5- Lichen planus bullosus.
6- Lichen planus circinatus.
7- Lichen plano-pilaris: follicular papules which result in cicatricial alopecia.
8- Lichen planus actinicus: on sun exposed areas in the form of annular
lesions with violet brown centre and well defined hypopigmented margin.
9- Lichen planus of mucous membrane: (White streaks or network on the
buccal mucosa, fixed white plaques on the tongue or ulcerative lesions).
10- Lichen planus of palms and soles: firm rough non itchy deep yellowish
11- Lichen planus of the nails: thinning of nail plate, linear ridges and
grooves, adhesions between dorsal nail fold and nail bed may cause partial
destruction of nail (pterygium).
1-Compact hyperkeratosis.
2-Focal hypergranulosis.
3-Irregular acanthosis and irregular elongation of rete
ridges giving a (saw toothed appearance).
4-Liquefactive degeneration of basal layer.
5-Band like inflammatory infiltrate.
1-Assurance and avoidance of stress
2-Topical therapy:
a- Fluorinated topical steroid ointment
b- Topical tacrolimus
c- Intralesional steroids
(Hypertrophic LP and lichen planus of nail)
3-Systemic therapy:
b-Systemic steroids (15-20mg/day for 6 weeks) indicated in:
1-severs pruritic or generalized cases
2-ulcerative mucous membrane lesions
3-progressive nail destruction
4-extensive lichenplanopilaris to prevent cicatricial alopecia
c- Retinoids
d- Cyclosporin A
e- Antimalarials for actinic L.P
 It is an acute self limited disorder
characterized by superficial, scaly
lesions on the trunk.
 It is more common in spring and
Clinical picture:
1- The primary lesion is the herald patch.
2- It is followed after 5-15 days by multiple similar
macules or patches.
3- The long axes of lesions follow lines of cleavage
parallel to the ribs in a Christmas tree pattern on the
upper chest and back.
4- The eruption fades within 4-8 weeks.
1- Classical type.
2- Inverted type.
3- Abortive type.
4- Localised type.
a- Infective agent: virus (HHV6-7).
b-Drug induced (pityriasiform drug eruption) as
captopril, metronidazole, ketotifen and
c- Autoimmune disease.
3-Calamine lotion
4-Narrow band UVB
 This is a chronic disease characterized
by follicular hyperkeratosis, branny
scales, orange red erythema and
palmoplanter keratoderma.
 It may be dominantly inherited.
 Vitamin A deficiency is also reported.
Clinical signs:
1-Diffuse scaliness of scalp.
2- Patches showing keratotic follicular papules.
3- Dry scaly erythematous areas simulating psoriasis.
4- Hyperkeratosis of palms and soles.
5- Follicular hyperkeratosis of proximal phalanges of
fingers and toes.
6- Nails: dull, thickened rough dystrophic.
7-Erythroderma with islands of normal skin.
Classical adult type (most common
Atypical adult type (5%)
Classical jeuvenile type (10%)
Circumscribed jeuvenile type (25%)
Atypical jeuvenile type (5%)
1-Emollients in cases of erythroderma to reduce scaling
and restore skin barrier
2-Topical steroids and salicylic acid ointment
3-Topical vitamin D analogues (calcipotriol)
4-Oral Vit A: 150,000-300,000 IU/day
5-Isotretinoin and acitretin
6-Methotrexate 10-25mg/week
7-Narrow band UVB
8-PUVA alone or/and oral retinoid