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Query: UMLS:C0008370 (cholestasis)
 9,378 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pruritus is a common manifestation of dermatologic diseases, including xerotic eczema, atopic dermatitis, and allergic contact dermatitis. Effective treatment of pruritus can prevent scratch-induced complications such as lichen simplex chronicus and impetigo. Patients, particularly elderly adults, with severe pruritus that does not respond to conservative therapy should be evaluated for an underlying systemic disease. Causes of systemic pruritus include uremia, cholestasis, polycythemia vera, Hodgkin's lymphoma, hyperthyroidism, and human immunodeficiency virus (HIV) infection. Skin scraping, biopsy, or culture may be indicated if skin lesions are present. Diagnostic testing is directed by the clinical evaluation and may include a complete blood count and measurement of thyroid-stimulating hormone, serum bilirubin, alkaline phosphatase, serum creatinine, and blood urea nitrogen levels. Chest radiography and testing for HIV infection may be indicated in some patients. Management of nonspecific pruritus is directed mostly at preventing xerosis. Management of disease-specific pruritus has been established for certain systemic conditions, including uremia and cholestasis.
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PMID:Pruritus. 1452 1

The neurophysiology of itch, the dominant symptom of skin disease, has previously received scant attention. Recent advances in the neurophysiology and molecular basis of itch include the use of microneurography to demonstrate the existence of a subset of itch-dedicated afferent C neurons distinct from neurons which transmit pain; use of functional positron emission tomography (PET) and magnetic resonance imaging (MRI) of the brain to reveal an itch-specific activation matrix, and new evidence of a functional "dialogue" between C neuron terminals and dermal mast cells in which recently described proteinase-activated receptor type 2 (PAR2) and transient receptor potential vanilloid 1 (TRPV1) receptors, proteases and endovanilloids play a major role. As a necessary prerequisite to diagnosis and management, a pathophysiologically based classification of itch is proposed. Recent advances in understanding of the pathomechanisms of itch of cholestasis include the role of opioids and opioid antagonists. Focusing on neurogenic itch (itch without visible rash), common causes are reviewed and guidelines for laboratory and radiological investigation are proposed. A stepwise approach to management of generalised itch is recommended, including broadband or narrow band ultraviolet (UV), tricyclics such as doxepin, opioid antagonists including naltrexone and selective serotonin reuptake inhibitors (SSRIs) such as paroxetine. For troublesome localised itches such as insect bite reactions, physical urticaria, lichen simplex chronicus or, less commonly, notalgia paraesthetica, brachioradial pruritus, local cooling devices which rely on the cooling action of dimethyl ethers on thermosensitive TRP voltage-sensitive ion channels are now commercially available for shortterm relief.
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PMID:Recent advances in pathophysiology and current management of itch. 1792 91

There have been considerable advances in our understanding of the pathophysiology of pruritus in recent years. The purpose of this review was to highlight itch entities in women, and in particular pruritic vulvar dermatoses that women experience among different age groups. Unique temporal shifts may contribute to the etiology of many of these conditions. These changes lead to cyclical changes in the skin's basic composition. Specifically, estrogen receptors have been detected on keratinocytes that respond to rising and falling levels of estrogen. These receptors lead to changes in skin hydration, collagen content, and in the concentration of glycosaminoglycans that form the skin barrier. In addition, hormonal pH changes associated with the menstrual cycle may be an important factor in the aggravation of itch as increasing pH is known to activate the proteinase-activated receptor-2, a well-known itch mediator. Common pruritic conditions in women that will be discussed include atopic and irritant dermatitis, psoriasis, lichen sclerosus, infectious vulvovaginitis, vulvovaginal candidiasis, atrophic vulvovaginitis, squamous cell carcinoma, lichen simplex chronicus, and neuropathic itch. We also examine pruritic conditions associated with pregnancy including pemphigoid gestationis, polymorphic eruption of pregnancy, intrahepatic cholestasis of pregnancy and atopic eruption of pregnancy. Finally, acceptable and contraindicated antipruritic agents in pregnancy are examined.
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PMID:Female-specific pruritus from childhood to postmenopause: clinical features, hormonal factors, and treatment considerations. 2355 72