pityriasis


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pityriasis

 [pit″ĭ-ri´ah-sis]
any of various skin diseases characterized by the formation of fine, branny scales.
acute lichenoid pityriasis an acute or subacute, sometimes relapsing, widespread macular, papular, or vesicular eruption that tends to crusting, necrosis, and hemorrhage; when it heals it leaves pigmented depressed scars, followed by a new crop of lesions. Progression to the chronic lichenoid form occasionally occurs.
pityriasis al´ba a chronic condition with patchy scaling and hypopigmentation of the skin of the face.
chronic lichenoid pityriasis a chronic brown to red-brown scaly macular eruption, seen mainly on the trunk, with epidermal changes and a perivascular lymphocytic infiltrate. It may arise independently or happen as a progression of the acute lichenoid form.
pityriasis ro´sea a common acute or subacute, self-limited exanthematous disease of unknown etiology. It begins with a solitary red to tan plaque (herald plaque), usually on the trunk, arms, or thighs, which is followed by similar but smaller papular or macular lesions; these later may peel and leave a scaly collarette.
pityriasis ru´bra pila´ris a chronic inflammatory skin disease marked by pink scaling macules and cone-shaped horny follicular papules; it usually begins with severe seborrhea of the scalp and face, associated with keratoderma of palms and soles.
pityriasis versi´color tinea versicolor.

pit·y·ri·a·sis

(pit-i-rī'ă-sis),
A dermatosis marked by branny desquamation.
[G. fr. pityron, bran, dandruff]

pityriasis

/pit·y·ri·a·sis/ (pit″ĭ-ri´ah-sis) any of various skin diseases characterized by the formation of fine, branny scales.
pityriasis al´ba  a chronic condition with patchy scaling and hypopigmentation of the skin of the face.
pityriasis ro´sea  a dermatosis marked by scaling, pink, oval macules arranged with the long axes parallel to the cleavage lines of the skin.
pityriasis ru´bra pila´ris  a chronic inflammatory skin disease marked by pink scaling macules and horny follicular papules, beginning usually with seborrhea of the scalp and face, with keratoderma of palms and soles.
pityriasis versi´color  tinea versicolor.

pityriasis

(pĭt′ĭ-rī′ə-sĭs)
n. pl. pityria·ses (-sēz′)
Any of various skin diseases of humans and animals, characterized by epidermal shedding of flaky scales.

pityriasis

[pitərī′əsis]
Etymology: Gk, pityron, bran
any of a number of skin diseases that have in common lesions that resemble dandrufflike scales without obvious signs of inflammation.

pit·y·ri·a·sis

(pit'i-rī'ă-sis)
A dermatosis marked by branny desquamation.
[G. fr. pityron, bran, dandruff]

pityriasis

Any skin condition featuring bran-like scaling of the skin.

pityriasis

a group of skin diseases in humans characterized by branlike scales on the skin surface. The skin is not thickened and its surface is unbroken. Pityriasis rosea of pigs is the only diseases in animals that is similar.

pityriasis rosea
a disease of pigs, most commonly white breeds such as Landrace, up to 3 months old characterized by circular lesions 1 inch (2-3 cm) diameter which often coalesce to produce large irregular lesions. The central area of the lesion is an area of comparatively normal skin, covered by thin brown scales and surrounded by a very narrow, 1 to 2 mm raised zone of erythema. There is no irritation or no bristle loss and spontaneous recovery is usual. The etiology is unknown. Called also porcine juvenile pustular psoriasiform dermatitis, pseudoringworm.
References in periodicals archive ?
Keywords: Itraconazole, Pityriasis versicolor, Topical clotrimazole.
Infliximab-induced pityriasis lichenoides chronica in a patient with psoriasis.
Treatment options for pityriasis rubra pilaris including biologic agents: a retrospective analysis from an academic medical center.
In addition to the moist slide of Potassium Hydroxide, a scotch tape (transparent cellophane tape) slide was collected as well from the patients suspected to Pityriasis Versicolor.
Additional evidence that pityriasis rosea is associated with reactivation of human herpesvirus-6 and -7.
Best known and most frequent is pityriasis versicolor (PV) [4] a chronic and recurrent skin disease occurring primarily in hot and humid climates.
9) mentioned that the presence of HPV infection can induce pigmentation in lesions such as pigmented flat warts, pigmented condyloma, pityriasis versicolor-like lesions in epidermodysplasia verruciformis, and pigmented Bowen disease, indicating the potential to activate the melanocytes.
Henoch-Schonlein purpura, psoriasis, pityriasis lichenoides, pityriasis rosea, lichen planus, pityriasis rubra pilaris, erythema multiforme, atopic dermatitis, granuloma annulare, and pigmented purpuric dermatosis were the most frequent skin disorders diagnosed dermatopathologically.
Study of the distribution of Malassezia species in patients with pityriasis versicolor and healthy individuals in Tehran, Iran.
Trace elements in serum of pityriasis alba patients.
One case of Pityriasis Rosea, resistant to routine mode of treatment was seen, but no other literature mentions its association.