Erythematosquamous disorders
By
Prof. Eman Saad Adel-Azim Professor of Dermatology,
Andrology & STDs
Psoriasis
Lichen planus Pityriasis rosea
Pityriasis Rubra Pilaris
Erythematosquamous disorders
Clinically
It is a chronic idiopathic disease of the skin and mucous membranes, hair and nails
Common at 30-60 years, no sex predilection Clinical picture (6P’s):
-Itchy (pruritic): rubbing more than scratching) -Shiny (polished)
-Flat-topped (planer) -polygonal
-Violaceous (purple) papules
-Wikham’s striae (white lines) on the surface
Any part of the body, wrists, back of hands, forearms, lumber region, glans penis and lower extremities
Nails: longitudinal ridging , pterygium formation,
complete dystrophy or twenty-nail dystrophy (thin, brittle opalescent 20 nails).
lichen planus actinicus: On sun-exposed areas Mucous membrane lesions:
- white reticular streaks occur on buccal mucosa, tongue and lips
- white plaques
- ulcerative erosive lesions
Healing ocurrs with deep pigmentations after few months Clinical types:
- plaques (coalescence of papules)
- Linear (koebner’ s phenomenon)
- Annular
- Hypertrophic LP: extremely pruritic, thick hyperkeratotic plaques usually distributed on shins or dorsal aspect of foot
- Atrophic LP
- Acute (eruptive) LP
- Bullous
- Ulcerative LP
- Actinicus: on exposed parts of the skin
- Lichen planopilaris: cicatricial alopecia
Etiological and associated factors
Immunological: may be associated with
autoimmune disorders e.g alopecia areata, ulcerative colitis
Light (lichen planus actinicus) Drugs (antimalarials)
Diabetes
Viral hepatitis: Chronic active hepatitis (HCV&HBV)
Underlying malignancies
Treatment
Systemic steroids: for generalized sever cases
Topical steroids:
- creams and ointment
- Intralesional injection of triamcinolone in hypertrophic type and in nail affection
Antihistamines: for itching Antimalarials: in actinic LP
Pityriasis Rosea
Acute
Self-limiting disease seen mainly in adults Spring and autumn
Remission usually within 6-8 weeks and recurrences are uncommon
Etiology
Unknown
Viral aetiology has been suggested Cell-mediated immune mechanism
Common in young adults
Usually asymptomatic ( itching)
Trunk and proximal extremities: long axis of lesions are parallel to the ribs
Clinical picture
Herald patch appears first as sharply
defined, bright-red (Rosy), round or oval patch covered by fine collarette of scales at periphery (on anterior chest, thigh,
upper arm or neck) followed after 5-15
days by multiple symmetrical oval macules or maculopapules, erythematous covered with fine scales.
The secondary eruption usually follows the lines of cleavage of the skin in a
distribution parallel to the ribs (Christmas tree pattern)
The center tends to clear with marginal collarette of scales
They are usually confined to trunk, neck and proximal extrimities.
(T –shirt-Short distribution) Slight or absent pruritus.
Fading occurs within 4-7 weeks without trace, but it can persist for 5 months or more.
Types
Site
Abortive type: Only helard patch not followed by secondary lesions
Inverted type: on face and extremities Localized
Generalized
Morphology
Papular, urticarial, papul-vesicular, vesicular or even pustular, purpuric forms
DD
-Tinea circinata
- Secondary syphilitic rash - Circinate impetigo
Treatment
Not required in all cases (self-limiting) Reassurance
Avoid irritation :hot baths, harsh and drying soaps and woolen clothing
Symptomatic: Calamine lotion or mild topical steroid
Antihistamines
UVB; shorten the course, extent of eruption and pruritus