1. Psoriasis and Other Papulosquamous Disease

2. Definitions
Psoriasis is the most common chronic papulosquamous disease
The classic lesion of psoriasis is a well-demarcated erythematous plaque with a silvery (micaceous) scale
Removal of the scale commonly results in bleeding (Auspitz sign)

3. Psoriasis is common (2% of the population)
As a chronic inflammatory disease it is associated with systemic disease that might be preventable
Cardiovascular disease
Obesity and smoking precede the development of moderate to severe psoriasis
Early, aggressive treatment might lessen the occurrence of some of the co-morbidities and improve survival

4. Epidemiology Psoriasis affects roughly 2% of the population
Equal sex distribution.
Onset is bimodal – Peaks between and years of age, but it can occur at any age from birth to death.
Familial cases are not uncommon

5. Etiology/Pathogenesis
Genetic basis for the disease is not fully understood
Environmental trigger factors
Trauma – Koebner phenomenon
Stress
Streptococcal infection
Drugs – e.g. lithium, beta blockers, possibly antimalarial agents
Pustular psoriasis has been associated with the withdrawal of corticosteroid therapy
Psoriasis is a disease associated with chronic inflammation and a variety of immunologic and cytokine abnormalities are believed to be related to disease expression

6. Clinical Variants Psoriasis vulgaris Guttate psoriasis
Pustular psoriasis
Inverse psoriasis
Erythrodermic psoriasis

7. Psoriatic arthritis Affects between 7 & 21% of patients with psoriasis
May occur prior to, concurrent with or subsequent to psoriasis
More common in patients with moderate to severe cutaneous disease and those with nail involvement

8. Psoriasis Vulgaris

9. Guttate Psoriasis

10. Pustular Psoriasis Localized pustular psoriasis
Generalized pustular psoriasis

11. Erythrodermic Psoriasis

12. Koebner Phenomenon

13. Nail Disease in Psoriasis

14. Psoriatic Arthritis

15. Diagnosis of Psoriasis
Clinical diagnosis
Exclude other papulosquamous diseases and chronic eczemas
When the clinical disease is typical, then the histopathological features are also characteristic, however when the disease is atypical the histopathology is often non-specific

16. Differential Diagnosis
Chronic Dermatitis
Seborrheic Dermatitis
Pityriasis rosea
Lupus erythematosus
Dermatophyte infection
Cutaneous T-cell lymphoma (mycosis fungoides)
Lichen planus

17. Chronic Atopic Dermatitis

18. Chronic Dermatitis

19. Pityriasis Rosea

20. Secondary Syphilis

21. Cutaneous Lupus Erythematosus

22. Dermatomyositis

23. Dermatophyte Infection

24. Onychomycosis

25. Cutaneous T-cell Lymphoma

26. Management of Psoriasis
Patient education
Not curable
Not contagious
Common disorder
Exacerbating factors
Categorize into localized v. generalized disease

27. Categorization of Psoriasis
Localized disease
Topical treatments
Generalized disease
Phototherapy
Systemic therapy

32. Conclusions - I
Psoriasis is usually easy to diagnose and can be distinguished from other papulosquamous diseases
Appropriate management includes a categorization about the need for topical v. phototherapy v. systemic therapy
Most patients with extensive psoriasis should be referred for specialized dermatological care

33. Conclusions - II
Psoriasis is a systemic disease with associations beyond arthritis including obesity, metabolic syndrome, and atherosclerotic vascular disease
Smoking confers an increase risk of psoriasis.
Interventions aimed at weight reduction, smoking cessation, control of hypertension, etc. might be beneficial for control of psoriasis along with improved survival