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Psoriasis. Dr yazan alrashdan Department of biopharmaceutics and clinical pharmacy Faculty of pharmacy University of jordan y.alrashdan@JU.EDU.JO. Definition and facts Epidemiology Classification Signs and symptoms Etiology Diagnosis Management Prognosis .
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Psoriasis Dr yazanalrashdan Department of biopharmaceutics and clinical pharmacy Faculty of pharmacy University of jordan y.alrashdan@JU.EDU.JO
Definition and facts • Epidemiology • Classification • Signs and symptoms • Etiology • Diagnosis • Management • Prognosis University of Jordan/Faculty of Pharmacy
A a common chronic inflammatory skin disorder characterized by recurrent exacerbations and remissions of thickened, erythematous, and scaling plaques. • Occurs when the immune system sends out faulty signals that speed up the growth cycle of skin cells. • Is NOT contagious. • Occurs on the skin of the elbows and knees, scalp, palms of hands and soles of feet, and genitals. • Fingernails and toenails are frequently affected. • Can also cause inflammation of the joints (psoriatic arthritis; 10-40%). • The cause not fully understood, however, genetics plus local psoriatic changes are the favorable perpetrators. University of Jordan/Faculty of Pharmacy
Epidemiology • Psoriasis affects both sexes equally. • Can occur at any age (most commonly appears for the first time between the ages of 15 and 25 years). • The prevalence of psoriasis in Western populations is estimated to be around 2-3%. • Around one-third of people with psoriasis report a family history of the disease. • Onset before age 40 usually indicates a greater genetic susceptibility and a more severe or recurrent course of psoriasis. University of Jordan/Faculty of Pharmacy
Classification • Non-pustular: - Psoriasis vulgaris: the most common (80-90)% - Psoriatic erythroderma: often results from exacerbation of vulgaris particularly following the abrupt withdrawal of systemic treatment. • Pustular: - Appears as raised bumps that are filled with pus. - The skin under and surrounding the pustules is red and tender. - Can be localized to the hands and feet or generalized with widespread patches occurring randomly on any part of the body. University of Jordan/Faculty of Pharmacy
Signs • The typical lesion is a well-demarcated, pink to salmon-colored plaque covered by loosely adherent scale that is characteristically silver-white in color. • Nail changes occur in 30% of cases of psoriasis and consist of yellow-brown discoloration, with pitting, dimpling, separation of the nail plate from the underlying bed, thickening, and crumbling. University of Jordan/Faculty of Pharmacy
Symptoms • Relatively asymptomatic. • Pruritus is a complaint in about 25% of patients. • Severe, widespread psoriasis can involve fever and chills. University of Jordan/Faculty of Pharmacy
Severity: - Mild - Moderate - Severe • The Psoriasis Area Severity Index (PASI): - The most widely used measurement tool for psoriasis. - Combines the assessment of the severity of lesions and the area affected into a single score in the range 0 (no disease) to 72 (maximal disease). University of Jordan/Faculty of Pharmacy
Etiology • There are two main hypotheses: 1. Considers it as a disorder of excessive growth and reproduction of skin cells (the problem is simply seen as a fault of the epidermis and its keratinocytes). 2. Considers it as being an immune-mediated disorder in which the excessive reproduction of skin cells is secondary to factors produced by the immune system. - T cells become active, migrate to the dermis and trigger the release of cytokines (TNFα) which cause inflammation and the rapid production of skin cells. University of Jordan/Faculty of Pharmacy
Triggering/Aggravating factors: - Stress (physical and mental) - Skin injury (Koebner phenomenon) - Streptococcal infection - Changes in season and climate - Certain medicines (lithium salt, β-blockers & chloroquine) - Excessive alcohol consumption, smoking and obesity - Hairspray, some face creams and hand lotions University of Jordan/Faculty of Pharmacy
Genetics • Psoriasis has a large hereditary component. • The MHC and T cells play pivotal role. • PSORS1 through PSORS9. • The major determinant is PSORS1 (accounts for 35-50%). It controls genes that affect the immune system or encode proteins that are found in the skin in greater amounts in psoriasis: - HLA (MHC-1) - IL12B - IL23R (interleukin-23 receptor) upregulating TNFα and NFκB University of Jordan/Faculty of Pharmacy
APC, antigen-presenting cell; GM-CSF, granulocyte-macrophage colony-stimulating factor; ICAM, intercellular adhesion molecule; INF, interferon; IL, interleukin; IP, inflammatory protein; MHC, major histocompatibility complex; MIG, monokine induced by interferon-; RANTES, regulated on activation, normal T-cell expressed and secreted; TNF, tumor necrosis factor; TH1, T-helper cell type 1; TH2, T-helped cell type 2; VCAM, vascular cell adhesion molecule; VEGF, vascular endothelial growth factor. Data from Mehlis S, Gordon KB. From laboratory to clinic: Rationale for biologic therapy. Dermatol Clin 2004;22(4):371–377, vii–viii. University of Jordan/Faculty of Pharmacy
Diagnosis: - Based on the appearance of the skin. - There are no special blood tests or diagnostic procedures. - A skin biopsy (or scraping) may be needed to rule out other disorders and to confirm the diagnosis. - When the plaques are scraped, one can see pinpoint bleeding from the skin below (Auspitz's sign) University of Jordan/Faculty of Pharmacy
Management/Treatment • Topical agents: 1. Moisturizers, mineral oil, and petroleum jelly may help soothe affected skin and reduce the dryness which accompanies the build-up of skin on psoriatic plaques. 2. Ointment and creams containing: - coal tar - dithranol (anthralin) - corticosteroids (desoximetasone & fluocinonide) - vitamin D3 analogues - retinoids University of Jordan/Faculty of Pharmacy
Phototherapy: - Wavelengths of 311–313 nm are most effective. - The amount of light used is determined by a persons skin type. - Increased rates of cancer from treatment appear to be small. - Psoralen and ultraviolet A phototherapy (PUVA). University of Jordan/Faculty of Pharmacy
Systemic agents: - Patients are required to have regular blood and liver function tests because of the toxicity of the medication. - Pregnancy must be avoided for the majority of these treatments. - Most people experience a recurrence of psoriasis after systemic treatment is discontinued. - Three main traditional systemic treatments are methotrexate, cyclosporine and retinoids. - Two drugs that target T cells are efalizumab and alefacept. - MAbs (infliximab, adalimumab, golimumab and certolizumab pegol). - Recombinant TNF-α decoy receptor (etanercept). - Antibodies have been developed against pro-inflammatory cytokines IL-12/IL-23 and IL-17. University of Jordan/Faculty of Pharmacy
Alternative therapy: - Fasting periods, low energy diets and vegetarian diets have improved psoriasis symptoms in some studies, and diets supplemented with fish oil. - Ichthyotherapy, which is practised at some spas in Turkey, Iran, Iraq, Croatia, Ireland, Hungary and Serbia. - Hypnotherapy. University of Jordan/Faculty of Pharmacy