File:Micrograph of<unk>  vulgaris.Micrograph of<unk>  vulgaris. Confluent parakeratosis,<unk> orm epidermal hyperplasia (A), EH, hypogranulosis, and influx of numerous neutrophils in the corneal layer (A), arrow. (B) Transepidermal migration of neutrophils from the dermis to the corneal layer (arrows). A diagnosis of<unk>  is usually based on the appearance of the skin. Skin characteristics typical for<unk>  are scaly, erythematous plaques, papules, or patches of skin that may be painful and itch. No special blood tests or diagnostic procedures are usually required to make the diagnosis. The differential diagnosis of<unk>  includes dermatological conditions similar in appearance such as discoid eczema, seborrheic eczema, pityriasis rosea (may be confused with guttate<unk> , nail fungus (may be confused with nail<unk>  or cutaneous T cell lymphoma (50% of individuals with this cancer are initially misdiagnosed with<unk> . Dermatologic manifestations of systemic illnesses such as the rash of secondary syphilis may also be confused with<unk> . If the clinical diagnosis is uncertain, a skin biopsy or scraping may be performed to rule out other disorders and to confirm the diagnosis. Skin from a biopsy shows clubbed epidermal projections that interdigitate with dermis on microscopy. Epidermal thickening is another characteristic histologic finding of<unk>  lesions. The stratum granulosum layer of the epidermis is often missing or significantly decreased in<unk> oriatic lesions; the skin cells from the most superficial layer of skin are also abnormal as they never fully mature. Unlike their mature counterparts, these superficial cells keep their nuclei. Inflammatory infiltrates can typically be seen on microscopy when examining skin tissue or joint tissue affected by<unk> . Epidermal skin tissue affected by<unk> oriatic inflammation often has many CD8+ T cells, while a predominance of CD4+ T cells makes up the inflammatory infiltrates of the dermal layer of skin and the joints. Classification Morphological<unk>  Type ICD-10 Code<unk>  Vulgaris L40.0 Generalized pustular<unk>  L40.1 Acrodermatitis continua L40.2 Pustulosis palmaris et plantaris L40.3 Guttate<unk>  L40.4<unk> oriatic arthritis L40.50<unk> oriatic spondylitis L40.53 Inverse<unk>  L40.8<unk>  is classified as a papulosquamous disorder and is most commonly subdivided into different categories based on histological characteristics. Variants include plaque, pustular, guttate, and flexural<unk> . Each form has a dedicated ICD-10 code.<unk>  can also be classified into nonpustular and pustular types. Pathogenetic Another classification scheme considers genetic and demographic factors. Type 1 has a positive family history, starts before the age of 40, and is associated with the human leukocyte antigen, HLA-Cw6. Conversely, type 2 does not show a family history, presents after age 40, and is not associated with HLA-Cw6. Type 1 accounts for about 75% of persons with<unk> . The classification of<unk>  as an autoimmune disease has sparked considerable debate. Researchers have proposed differing descriptions of<unk>  and<unk> oriatic arthritis; some authors have classified them as autoimmune diseases while others have classified them as distinct from autoimmune diseases and referred to them as immune-mediated inflammatory diseases. Severity Distribution of severity No consensus exists about how to classify the severity of<unk> . Mild<unk>  has been defined as a percentage of body surface area (BSA)≤10, a<unk>  Area and Severity Index (PASI) score ≤10, and a Dermatology Life Quality Index (DLQI) score ≤10. Moderate to severe<unk>  was defined by the same group as BSA >10 or PASI score >10 and a DLQI score >10. The DLQI is a 10-question tool used to measure the impact of several dermatologic diseases on daily functioning. The DLQI score ranges from 0 (minimal impairment) to 30 (maximal impairment) and is calculated with each answer being assigned 0–3 points with higher scores indicating greater social or occupational impairment. The PASI is the most widely used measurement tool for<unk> . It assesses the severity of lesions and the area affected and combines these two factors into a single score from 0 (no disease) to 72 (maximal disease). Nevertheless, the PASI can be too unwieldy to use outside of research settings, which has led to attempts to simplify the index for clinical use.
Psoriasis
Onychomycosis
Parapsoriasis
Basal-cell carcinoma
Lupus vulgaris
Dermatitis
Vitiligo
Dandruff