Psoriasis Flashcards
What is the etiology of Psoriasis?
Psoriasis is a multifactorial disorder that is genetic and immune-mediated. Emotional stress and physical trauma can both exacerbate and precipitate the condition.
What is the pathogenesis of Psoriasis?
T-cell immunity plays an important role. Sensitized T cells infiltrate the skin, secreting cytokines and growth factors, leading to continuous stimulation of basal cells, increased cell turnover, inflammation, vascular proliferation, and angiogenesis.
What is the gross morphology of Psoriasis lesions?
Psoriasis plaques are covered with silvery scales (due to hyperkeratosis and parakeratosis), are bilateral, well-demarcated, and erythematous based. Nail abnormalities such as dystrophy, pitting, and onycholysis may also occur. The Auspitz sign is the appearance of microbleeding when crusts are removed.
What are the microscopic features of Psoriasis?
Microscopic features include acanthosis (deepening of rete ridges and thickening of the epidermis), parakeratosis (presence of nuclei in the stratum corneum), neutrophilic microabscesses in the epidermis, and tortuous papillary dermal vessels.
What are the clinical features of Psoriasis?
Psoriasis can present at any age from infancy onwards, generally persists lifelong with fluctuating extent and severity, is not itchy, has a symmetrical distribution, and can cause multi-system disorders such as psoriatic arthritis, myopathy, enteropathy, and immunodeficiency.
How is Psoriasis diagnosed?
Psoriasis is diagnosed clinically based on morphology. A punch biopsy can provide a definitive diagnosis
What are the treatment options for Psoriasis?
Treatment includes emollients, coal tar preparations, dithranol, salicylic acid, Vitamin D analogues (e.g., Calcipotriol), topical corticosteroids, sunshine/phototherapy, and systemic treatments if severe (e.g., Methotrexate, Ciclosporin, Acitretin).
What is the prognosis for Psoriasis?
Psoriasis is chronic, not curable, and can be exacerbated by stress.
What are the classical locations for Psoriasis lesions?
Classical Psoriasis occurs on the scalp, extensor areas of extremities (especially elbows and knees), the umbilicus, and the buttocks.
What are the nail changes associated with Psoriasis?
Psoriatic nail changes include pitting, thickening of the nail bed, or distal onycholysis (brownish oil-like changes on the distal nail where the nail is detached from the nail bed).
What is the clinical significance of Psoriatic Arthritis?
Psoriatic arthritis affects the small joints of the hands and feet in 5-10% of patients and may become mutilating and widespread.
What systemic treatments are used for severe Psoriasis or Psoriatic Arthritis?
Systemic treatments include NSAIDs (e.g., ibuprofen, indomethacin, naproxen, salazosulphapyridine) and methotrexate, which is effective in severe and arthropathic psoriasis and may be used in HIV-infected patients
What are the common types of Psoriasis?
The common types of psoriasis include Plaque Psoriasis, Guttate Psoriasis, Inverse Psoriasis, Pustular Psoriasis, and Erythrodermic Psoriasis.
What is the PASI score?
he Psoriasis Area and Severity Index (PASI) score is a tool used to measure the severity and extent of psoriasis, factoring in the size, redness, thickness, and scale of lesions.
What role do biologics play in Psoriasis treatment?
Biologics target specific parts of the immune system, such as TNF-alpha, IL-17, and IL-23, to reduce inflammation and prevent psoriatic lesions from forming.
