ERYTHEMATOSQUAMOUS DISEASES Dr. Sahar Ismail

1. ERYTHEMATOSQUAMOUS DISEASES Dr. Sahar Ismail

2. Psoriasis الصدفية

3. Psoriasis is a common, chronic, recurrent inflammatory disease of the skin characterized by round, circumscribed, erythematous, scaly patches of various sizes, covered by silvery white scales.

4. Epidemiology: • Psoriasis affects about 1-2% of the general population. • It is more common in cold northern countries. • Both sexes are equally affected. • It affects all ages.

5. Etiology: • The etiology is unknown; the suggested causes are: • Genetic predisposition; family history is common. • Immunologicalabnormalities. • Infection; streptococcal infection precedes guttate psoriasis. • Trauma; napkin psoriasis, koebner’s phenomenon. • Sunlight

6. Pathogenesis: • Rapid proliferation of the epidermal cells with no enough time for maturation results in parakeratosis and scale formation. • Histopathology: • Parakeratosis. • Absence of granular layer. • Epidermal micro-abscesses. • Dilated capillary loops in the upper dermis.

7. Clinicalpicture: • Psoriasis is an asymptomatic disease but itching may be present in acute spreading cases and the flexural type. • The characteristic lesions are erythematous papules and plaques covered with dry, silvery-white scales. • The eruption is usually bilateral and symmetrical and may vary from a solitary lesion to more than 100.

9. Any site can be affected but the commonest are; extensor surfaces of the limbs, elbows, knees, sacral region, scalp and nails. • The course of the disease is chronic and unpredictable.

10. Clinical types: • Psoriasis vulgaris: Classical type. • Annular psoriasis: Ring shaped lesions.

11. Guttate psoriasis: Lesions are water drops size.

12. Discoid (Nummular) psoriasis: Coin-shaped lesions.

13. Scalp psoriasis: Multiple plaques or diffuse involvement with no loss of hair.

14. Nail psoriasis: 1-loss of translucency 4-Subungual hyperkeratosis 2-Pitting 3-onycholysis

15. Flexural psoriasis: Affects the flexures as the groins and axillae. Due to friction and moisture scaling is reduced or absent and itching is common.

16. Pustular psoriasis: • May be localized or generalized. • The pustules are sterile.

17. Erythrodermic psoriasis: Erythema and scaling involving almost all (90%) the skin surface.

18. Arthropathic psoriasis: Psoriasis associated with arthropathy. It may be in the form of distal arthritis (distal inter-phalangeal joints) or rheumatoid-like arthritis.

19. Auspitz sign: Scraping of the psoriatic lesion with removal of the scales results in the appearance of bleeding points. These bleeding points are due to injury of the dermal papillae where the dilated capillaries are found.

20. Koebner’s phenomenon: It is the appearance of typical lesions at sites of injuries. The phenomenon may occur in psoriasis, lichen planus and plane warts.

21. Differentialdiagnosis: • Seborrhoeic dermatitis. • Pityriasis rosea. • Pityriasis rubra pilaris. • Lichen planus.

22. Treatment • A- Topical therapy • Corticosteroids. It is the most frequent therapy, used with occlusion is more effective. Intra-lesional injection of steroids is very useful in small lesions. • Tars. Crude coal tar 2-5%. • Dithranol (Anthralin). Very irritant. • Salicylic acid. 3-5%. • Vitamin D3 analogue (Calcipotriol). • Ultraviolet light. Artificial UVB, sunlight or narrowband UVB.

23. B- Systemic therapy • It is used only for the severe forms of the disease as erythrodermic, pustular and arthropathic psoriasis: • Corticosteroids. • Methotrexate . • Retinoids (analogues of vitamin A). • Cyclosporine A (immunosuppressive drug). • PUVA. It involves the use of a psoralen (P) followed by exposure to long wave ultraviolet light (UVA).

24. Lichen planus الحزاز المنبسط

25. Lichen planus is a chronic pruritic disease of the skin and mucous membranes. • Etiology • The etiology of lichen planus is unknown; the suggested causes are: • Immunological factors. • Inherited factors. • Drugs as anti-malarials. • Hepatitis C virus.

26. Clinical picture • The pathognomonic lesions: • are violaceous, flat-topped, shiny, polyangular papules. On the surface white streaks (Wickham’s striae) cross the lesions.

27. The sites of predilection are the flexor aspect of wrists and forearms, lumbar region, medial thigh and around the ankles. • The lesions usually heal with deep pigmentation. • Mucous membrane lesions are very common, occurring in 30-70% of cases. • Itching is often prominent.

28. Clinical varieties: • Ordinary (classical) lichen planus

29. Hypertrophic lichen planus: • Verrucous plaques common on lower limbs.

30. Atrophic lichen planus:May be the result of resolved lesions.

31. Linear lichen planus: • Mostly one band or streak.

32. Annular lichen planus • Ringed lesions common on penis.

33. Follicular lichen planus. • Affects hair folliclesand cause cicatricial alopecia

34. Actinic lichen planus: • Affects areas exposed to sun.

35. Lichen planus of mucous membranes: • The buccal mucosa and tongue are most often involved, white streaks forming lace-like are characteristic

36. Treatment: • Topical corticosteroids. • Oral antihistamines. • Systemic corticosteroids for extensive cases.

37. Pityriasis rosea النخالة الوردية

38. Pityriasis rosea is an acute self-limiting disease affecting children and young adults and characterized by a distinctive skin eruption. It is more common in spring and autumn.

39. Etiology: • The etiology is unknown, the suggested theories are: • Infective (viral). • Drugs.

40. Clinical picture: • The first manifestation of the disease is usually the appearance of the herald patch, which is larger than the lesions of the later eruption and is usually situated on the trunk, thigh or upper arm. It is sharply defined, red, round or oval macule, 2-5 cm in diameter and covered by fine scales.

42. After 5 to 15 days, the general eruption begins to appear in crops over a week or 10 days. • The lesions have the same appearance of the herald patch. • The center tends to clear, with a marginal collarets of scales. The long axes of the lesions are usually parallel to the ribs.

43. The eruption is bilateral and symmetrical and involves the trunk and the proximal parts of the extremities. • Subjective symptoms are usually absent but there may be slight or moderate itching. • The skin lesions commonly fade after 3-6 weeks.

44. Atypical varieties: • Inverted type: • Affects only the face and limbs. • Abortive type: • No lesions except the herald patch. • Localized type: • Confined to a single region.

45. Treatment: • Reassurance as the disease is self-limiting. • Antihistamines for itching. • Topical corticosteroids. • Ultraviolet irradiation.

46. Pityriasis rubra pilaris:

47. Pityriasis rubra pilaris (PRP) is a chronic disease of unknown etiology characterized by: • circumscribed follicular keratoses, • Palmo-plantar keratoderma • erythroderma.

48. Clinical picture: • Circumscribed follicular keratoses. • Erythema and scaling of the face. • Diffuse scaling of the scalp. • Palmoplantar keratoderma. • Psoriasiform patches. • Erythroderma. • The nails are thickened, discolored and brittle.

50. Treatment: • Salicylic acid ointment 3-5%. • Systemic retinoids in severe cases. • Methotrexate in severe cases.