Category: Diseases

Pityriasis versicolor (PV) is a chronic asymptomatic scaling dermatosis associated with the superficial overgrowth of the hyphal form of Pityrosporum ovale, characterized by well-demarcated scaling patches with variable pigmentation, occurring

Pitted keratolysis (PK) presents as defects in the thickly keratinized skin of the plantar foot with sculpted pits of variable depth, depending on the thickness of the stratum corneum, usually

Phytophotodermatitis (PPD) is an inflammation of the skin caused by contact with certain plants during recreational or occupational exposure to sunlight. The inflammatory response is a phototoxic reaction to photosensitizing

Phototoxic, which can occur in all individuals and is essentially an exaggerated sunburn response (erythema, edema, vesicles, etc.). Phototoxic drug reactions are more frequent than photoallergic drug sensitivity. Causes of

In photoallergic drug photosensitivity, the chemical agent (drug) present in the skin absorbs photons and forms a photoproduct; this photoproduct then binds to a soluble or membrane-bound protein to form

Two species of blood sucking lice of the order Anoplura have evolved to be obligate ectoparasites of humans: Pediculus humanus and Phthirius pubis. The two variants of Pediculus, the head

Pediculosis pubis, known as crabs or crab lice, is an infestation with the crab louse (Phthirus pubis), a millimeter-sized insect that infests the pubic hair, feeds on human blood, and

Pediculosis capitis is an infestation of the scalp by the head louse, which feeds on the scalp and neck and deposits its eggs on the hair; presence of head lice

Urticaria is composed of wheals (transient edematous papules and plaques, usually pruritic and due to edema of the papillary body). Angioedema is a larger edematous area that involves the dermis

Urticarial vasculitis is a multisystem disease characterized by cutaneous lesions resembling urticaria, except that wheals persist more than 24 h, generally up to 3 to 4 days. Fever, arthralgia, elevated