<\/span><\/h3>\nAcrocyanosis is the name given to cold peripheries mottled with cyanosis<\/span> (blue discoloration) or erythema<\/span> (reddened skin). Predisposes to chilblains.<\/p>\n<\/span>Chilblains (pernio)
\n<\/span><\/h3>\nChilblains arise due to a located<\/span> cold injury to exposed areas (most often, fingers and toes, ears). They present with erythema, cyanosis, edema<\/span>blisters and ulceration<\/span>. Lesions usually heal within several weeks, provided there is no further significant cold exposure. Severe pernio may be the presentation sign<\/span> of connective tissue<\/span> illness, especially systemic<\/span> lupus erythematosus (sable lupus) or systemic sclerosis<\/span>. However, they are also an occupational hazard for dairy farmers, fishermen and other outdoor workers.<\/p>\nSevere cold injuries can damage small bones in the digits<\/span>, which leads to microgeodic disease, swelling and sometimes bone fracture.<\/p>\nPreventing chilblains requires keeping fingers and ears warm and dry. A vasodilator medication such as oral nifedipine may be helpful.<\/p>\n\n<\/span>Chilblains<\/span><\/h5>\n<\/section>\n\n\n
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<\/span>Raynaud's phenomenon<\/span><\/span><\/h3>\nThe term Raynaud's disease refers to primary<\/span> Raynaud's phenomenon. Secondary Raynaud's phenomenon is associated with many underlying diseases, especially systemic sclerosis.<\/p>\nCharacteristically, painful attacks follow exposure of the fingers to cold. They turn white, then, in turn, cyanize and erythematous<\/span> before returning to a normal color.<\/p>\n\n<\/span>Raynaud's phenomenon<\/span><\/h5>\n<\/section>\n\n\n
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Raynaud's phenomenon<\/p>\n
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Raynaud's phenomenon<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Freezing<\/span><\/h3>\nFrostbite is due to severe cold injuries (subzero temperatures). The first signs are pallor<\/span> and numbness<\/p>\nTreat areas exposed to severe cold by rapid rewarming in a 40\u00b0 water bath (no further risk of frostbite). Late aftermath<\/span> include pain, numbness, feeling cold, hyperhidrosis<\/span>dystrophic nail<\/span>, fibrosis<\/span>, osteoporosis and cold intolerance.<\/p>\n<\/span>Cryoglobulinemia<\/span><\/h3>\nCryoglobulinemia is a condition in which proteins circulate in the bloodstream that can solidify in cold conditions. Cold precipitable proteins are deposited in cold areas (ears, toes, fingers). Cryoglobulinemia can present as livedo<\/span> reticular or superficial heart attack<\/span> or cutaneous<\/span> vasculitis<\/span>.<\/p>\n\n<\/span>Livedo reticularis<\/span><\/h5>\n<\/section>\n\n\n
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Livedo reticularis<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Cold urticaria<\/span>
\n<\/span><\/h3>\nCold hives and family<\/span> Cold urticaria are rare types of chronic<\/span> inducible<\/span> hives that arise during rewarming after exposure to cold. The most common acquired variety usually affects children and young adults.<\/p>\nWeals<\/span> It can affect any site, most frequently on the face and in exposed places. Scars persist for up to two hours (or longer, in familial cold urticaria). Cold hives can cause anaphylactoid<\/span> symptoms, for example when swimming in cold water.<\/p>\n\n<\/span>Ice-induced hives<\/span><\/h5>\n<\/section>\n\n\n
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Ice-induced hives<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>What skin changes occur due to heat?<\/span><\/h2>\n<\/span>Erythema ab igne
\n<\/span><\/h3>\nErythema abigne is due to local heat, such as a hot water bottle or being near a fire. It presents as erythema on a vascular<\/span> distribution<\/span> and is often followed by post-inflammatory<\/span> pigmentation<\/span>. No treatment is effective, but appearance improves over time.<\/p>\n\n<\/span>Erythema ab igne<\/span><\/h5>\n<\/section>\n\n\n
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Erythema ab igne<\/p>\n
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Erythema ab igne<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Erythromelalgia
\n<\/span><\/h3>\nErythromelalgia causes burning when the feet or hands are hot. The affected areas are erythematous or cyanotic. Some cases are associated with polycythemia<\/span>, thrombocythemia or lupus erythematosus. In these secondary cases, symptoms may respond to low doses of aspirin.<\/p>\n<\/span>Heat urticaria<\/span><\/h3>\nHeat urticaria is a local healing reaction to heat and is rare.<\/p>\n
<\/span>Cholinergic urticaria
\n<\/span><\/h3>\nCholinergic urticaria is a kind of <\/span>Chronic inducible urticaria caused by heat, emotional stress and exercise. The mechanism is uncertain, as healing can occur without sweating. It usually presents with numerous pruritus<\/span> Scars of 2\u20133 mm surrounded by a red flare, which persist for 15\u201330 minutes and are at least sometimes associated with exercise. Treatment may include oral antihistamines, phototherapy, propranolol, or scopolamine with variables effectiveness<\/span>.<\/p>\n\n<\/span>Cholinergic urticaria<\/span><\/h5>\n<\/section>\n\n\n
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Cholinergic urticaria<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Hyperhidrosis<\/span><\/h3>\nExcessive eccrine<\/span> discharge or hyperhidrosis can be generalized<\/span> or localized (most often in hands, feet, armpits<\/span> and face). Most cases occur in adolescence or young adulthood and appear to be due to idiopathic<\/span> hypothalamic<\/span> stimuli Hyperhidrosis is rarely due to systemic disorders such as hyperthyroidism<\/span> or hypothalamic disease when it is more likely to occur later in adult life.<\/p>\nHyperhidrosis is aggravated by thermal, emotional or gustatory<\/span> stimuli can result in bromhidrosis<\/span> and work difficulties. All patients should use medical grade antiperspirant lotions, which contain aluminum salts. Other treatments include iontophoresis, oral propantheline, propranolol, intradermal<\/span> botulinum toxin<\/span>, axillary liposuction or excision<\/span> of the affected skin, or in severe cases, sympathectomy<\/span>.<\/p>\n\n<\/span>Hyperhidrosis<\/span><\/h5>\n<\/section>\n\n\n
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Palmar hyperhidrosis<\/p>\n
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Iontopheresis<\/p>\n<\/p><\/div>\n<\/section>\n
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<\/span>Miliaria
\n<\/span><\/h3>\nMiliaria refers to sweat eruption<\/span> (prickly heat) due to clogged and perhaps localized sweat glands hyperproliferation<\/span> of specific