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Continuing Education Activity

Miliaria, also known as eccrine miliaria, heat rash, prickly heat, or sweat rash, is a frequently seen skin condition triggered by blocked eccrine sweat glands and ducts. The blockage leads to backflow of eccrine sweat into the dermis or epidermis, resulting in a rash comprised of sweat-filled vesicles under the skin. This activity reviews when this diagnosis should be considered, how to manage it, and the role of the interprofessional care team in caring for affected patients.

Objectives:

• Review the etiology of miliaria.

• Describe the signs and symptoms of miliaria.

• Explain how to distinguish miliaria from conditions that are more clinically concerning and require treatment.

• Summarize the importance of optimizing coordination amongst the interprofessional team to ensure appropriate evaluation and management of miliaria.

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Introduction

Miliaria, or eccrine miliaria, is a frequently seen skin disease triggered by blocked eccrine sweat glands and ducts, causing backflow of eccrine sweat into the dermis or epidermis.[1] This backflow results in a rash comprising sweat-filled vesicle formation under the skin. Other names for this skin condition include “heat rash,” “prickly heat,” or a “sweat rash.”[2] It is most common in warm, humid climates during the summer months. The 3 main types of miliaria are crystallina, rubra, and profunda and are classified by the depth of obstruction of the sweat duct causing clinical and histological differences. The rash is usually self-limited and resolves independently of treatment.

Etiology

Though miliaria affects all age groups and both genders equally, infants and children are at a higher risk due to eccrine duct immaturity.[3] Sweating is the most common risk factor for miliaria. Therefore, hot or humid conditions and high fevers are associated with miliaria. The following have been identified as causes of miliaria:

• Occlusion of the skin: Transdermal drug patches and tight clothing have been associated with miliaria.[4][5]

• Type I pseudohypoaldosteronism: Mineralocorticoid resistance results in loss of sodium through eccrine glands and has been associated with pustular miliaria rubra.[6][7][8]

• Strenuous physical activity

• Morvan syndrome: A rare autosomal recessive disease that results in hyperhidrosis, among other abnormalities, which predisposes to miliaria.[9][10]

• Medications: Drugs that induce sweating such as bethanechol, clonidine, and neostigmine have been linked to miliaria.[11] Additionally, few cases of isotretinoin-induced miliaria have been reported.[12]

Epidemiology

Miliaria frequently affects neonates and individuals suffering from increased sweating as well as those living in hot and humid climates. Although miliaria is seen in both genders and all races, each type affects a slightly different population. Miliaria crystallina, or sudamina, commonly affects neonates with the greatest incidence at 2 weeks of age or less. It affects between 4.5% to 9% of neonates.[13][14] It can also be seen in adults who have recently relocated to a warmer climate. Miliaria rubra, the most common form of miliaria, is frequently seen in neonates between 1 and 3 weeks of age. It can also affect up to 30% of adults living in hot and humid conditions.[3] Miliaria profunda is the rarest form of miliaria. It is most commonly seen in people who have recurrent episodes of miliaria rubra or individuals exposed to new warm climates such as military persons deployed in tropical climates.[15]

Pathophysiology

The main cause of miliaria is obstruction of the eccrine sweat glands or ducts. This can be due to cutaneous debris or bacteria such as Staphylococcus epidermidis with its formation of biofilms.[16][17] The obstruction leads to leakage of sweat into the epidermis or dermis, resulting in cellular overhydration, swelling, and further occlusion of the ducts.  More profound involvement of the eccrine gland or duct may lead to their rupture. The different types of miliaria have varying depths of cutaneous involvement. Miliaria crystallina occurs with ductal occlusion of the stratum corneum, miliaria rubra occurs with ductal occlusion in the epidermis at the subcorneal layers, and miliaria profunda results from the ductal occlusion in the dermal-epidermal junction, specifically the papillary dermis.

Histopathology

The histology of miliaria is different based on the type, as each is classified by the depth of obstruction of the eccrine duct. Miliaria crystallina displays subcorneal or intracorneal vesicles from the intraepidermal portion of the duct and may contain neutrophils. Miliaria rubra exhibits epidermal spongiosis with parakeratosis and vesicles in the epidermis communicating with the eccrine duct. It can have associated inflammatory lymphocytic infiltrate surrounding the duct and superficial vasculature. Miliaria profunda involves the intradermal spongiosis of the eccrine duct, and is comparable to miliaria rubra. Miliaria profunda differs from rubra by the further rupture of eccrine ducts and more significant lymphocytic inflammation. It is periodic acid-Schiff (PAS)-positive, diastase-resistant by microscopy.

History and Physical

Miliaria is a disorder involving vesicles, papules, and pustules of the skin. It is crucial to examine the skin closely for rash characteristics and location in order to arrive at an accurate diagnosis.

Miliaria crystallina appears as 1 to 2 mm superficial vesicles, affecting both adults and neonates usually younger than 2 weeks old. Since the pathophysiology involves the most superficial layer of the epidermis, the stratum corneum, the vesicles have a thin superficial layer. This results in the vesicles resembling water droplets on the skin that easily rupture.[11] The vesicles are superficial; therefore, an inflammatory response is typically absent. The upper trunk, neck, and head are the most commonly affected sites. The rash will usually appear within a few days of exposure to risk factors and will resolve within a day after the superficial layer of skin rubs off. [18]

Miliaria rubra is the most prevalent form of miliaria. The obstruction of eccrine ducts occurs in the deeper layers of the skin and involves an inflammatory response. This results in larger, erythematous papules and vesicles. A critical clinical diagnostic feature that helps differentiate miliaria rubra from folliculitis is minimal follicular involvement. If pustules are present, then miliaria rubra is called miliaria pustulosa and may indicate a bacterial infection. Because an inflammatory response is involved, patients may experience pruritic and painful symptoms. These symptoms may worsen during perspiration, causing more irritation. In neonates usually between the ages of 1 to 3 weeks, the groin, axilla, and neck are the most commonly affected areas. In adults, miliaria rubra is most likely seen in places where clothes rub on the skin such as the trunk and extremities. The face is usually spared. Superinfection with staphylococci may occur, and when impetigo or multiple abscesses are involved, the condition is called periporitis staphylogenes. [19] 

Miliaria profunda, due to a deeper involvement of the skin at the dermal-epidermal junction, results in firm, large, flesh-colored papules that are also not centered around the follicles. The eruption may vary with symptoms from extremely pruritic to asymptomatic. Miliaria profunda is usually seen in patients with numerous previous episodes of miliaria rubra. The rash distribution in adults mainly involves the trunk, but the arms and legs may also be involved. The skin rash usually appears within minutes to hours of perspiration and resolves within an hour of sweating cessation.

In both miliaria rubra and miliaria profunda, anhidrosis may occur in affected areas due to obstructed sweat glands. As such, heat exhaustion may occur due to ineffective thermoregulation in patients with largely affected areas and should be considered in the setting of a skin rash accompanied by hyperthermia.

Evaluation

Miliaria is a clinical diagnosis. Laboratory tests are often inconclusive and not helpful. Dermoscopy has been found to be a useful tool, particularly in people with darker skin, revealing large white globules with surrounding darker halos (white bullseye).[20] When in doubt, a skin punch biopsy can be useful to help with diagnosis. Please refer above to the histopathology section regarding findings. High-definition optical coherence tomography has assisted in finding the obstruction of the eccrine duct.[21]

Treatment / Management

With hot, sweaty conditions being the main risk factors for miliaria, general measures to decrease sweating, and eccrine duct blockage are warranted in the management of miliaria. This includes cooler environments, wearing breathable clothes, exfoliating the skin, removing skin occluding objects such as bandages or patches, as well as treating febrile illnesses.

Specific modalities for the treatment of miliaria are unique depending on the type. Miliaria crystallina is usually not treated as it is self-limited and usually resolves within 24 hours. Miliaria rubra treatment is geared towards decreasing inflammation, and therefore mild to mid-potency corticosteroids like triamcinolone 0.1% cream may be applied for one to two weeks. If miliaria pustulosa develops, topical antibiotics such as clindamycin are indicated to treat the superimposed bacterial infection.

Very little information exists regarding the treatment of miliaria profunda except the general measures listed above. However, the results of a study have shown improvement of miliaria profunda with the combined use of oral isotretinoin 40 mg per day for 2 months and topical anhydrous lanolin.[22]

Differential Diagnosis

• Viral exanthems or viral infections such as herpes simplex or varicella

• Cutaneous candidiasis or other fungal skin infections

• Folliculitis, whether bacterial or pityrosporum

• Neonatal acne or erythema toxicum neonatorum

• Drug rashes, particularly acute, generalized, exanthematous pustulosis

• Grover disease

• Arthropod bites

• Lymphocytoma cutis or cutaneous T-cell pseudolymphomas

Prognosis

The majority of miliaria cases resolve spontaneously after decreasing risk factors and moving to a cooler, less humid environment.

Complications

The most serious complication that may result from miliaria is anhidrosis, leading to poor thermoregulation and heat exhaustion. This may permanently disable a person from work or prevent an active person from continuing exercise or sports. Opportunistic bacterial superinfections may occur due to the changes in the affected epidermal layer by this skin condition.

Deterrence and Patient Education

Clinicians should educate patients about the causes and risk factors of miliaria, including hot, humid climates, and wearing non-breathable clothes. If a patient is predisposed to miliaria, the clinician should create a personalized plan for the patient that includes methods of avoiding overheating, and what to do when the rash appears. Clinicians should also educate patients on the signs and symptoms of heat exhaustion if they develop anhidrosis secondary to miliaria.

Enhancing Healthcare Team Outcomes

Miliaria is a generally benign skin disorder that occurs in patients of all ages and genders who are exposed to humid, warm climates. It is usually self-limited and resolves spontaneously in response to a cooler, dryer atmosphere. An interprofessional team that includes the primary clinician, nurses, and pharmacists contributes to improving outcomes in patients with miliaria. In situations where a rash appearing to be miliaria does not resolve quickly, a consultation with a dermatologist should be recommended to rule out other more serious conditions that may mimic miliaria.

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Figure

Miliaria. Contributed by DermNetNZ

References

1.

Wenzel FG, Horn TD. Nonneoplastic disorders of the eccrine glands. J Am Acad Dermatol. 1998 Jan;38(1):1-17; quiz 18-20. [PubMed: 9448199]

2.

El Anzi O, Hassam B. [Widespread miliaria crystallina: about a case]. Pan Afr Med J. 2018;30:69. [PMC free article: PMC6191250] [PubMed: 30344853]

3.

LYONS RE, LEVINE R, AULD D. Miliaria rubra, a manifestation of staphylococcal disease. Arch Dermatol. 1962 Sep;86:282-6. [PubMed: 14467655]

4.

Ale I, Lachapelle JM, Maibach HI. Skin tolerability associated with transdermal drug delivery systems: an overview. Adv Ther. 2009 Oct;26(10):920-35. [PubMed: 19967501]

5.

Carter R, Garcia AM, Souhan BE. Patients presenting with miliaria while wearing flame resistant clothing in high ambient temperatures: a case series. J Med Case Rep. 2011 Sep 22;5:474. [PMC free article: PMC3195105] [PubMed: 21939537]

6.

Onal H, Adal E, Ersen A, Onal Z, Keskindemirci G. Miliaria rubra and thrombocytosis in pseudohypoaldosteronism: case report. Platelets. 2012;23(8):645-7. [PubMed: 22150373]

7.

Urbatsch A, Paller AS. Pustular miliaria rubra: a specific cutaneous finding of type I pseudohypoaldosteronism. Pediatr Dermatol. 2002 Jul-Aug;19(4):317-9. [PubMed: 12220275]

8.

Akcakus M, Koklu E, Poyrazoglu H, Kurtoglu S. Newborn with pseudohypoaldosteronism and miliaria rubra. Int J Dermatol. 2006 Dec;45(12):1432-4. [PubMed: 17184247]

9.

Tabanelli M, Passarini B, Liguori R, Balestri R, Gaspari V, Giacomini F, Patrizi A. Erythematous papules on the parasternal region in a 76-year-old man. Clin Exp Dermatol. 2008 May;33(3):369-70. [PubMed: 18419614]

10.

Abou-Zeid E, Boursoulian LJ, Metzer WS, Gundogdu B. Morvan syndrome: a case report and review of the literature. J Clin Neuromuscul Dis. 2012 Jun;13(4):214-27. [PubMed: 22622167]

11.

Haas N, Martens F, Henz BM. Miliaria crystallina in an intensive care setting. Clin Exp Dermatol. 2004 Jan;29(1):32-4. [PubMed: 14723716]

12.

Gupta AK, Ellis CN, Madison KC, Voorhees JJ. Miliaria crystallina occurring in a patient treated with isotretinoin. Cutis. 1986 Oct;38(4):275-6. [PubMed: 3465509]

13.

Hidano A, Purwoko R, Jitsukawa K. Statistical survey of skin changes in Japanese neonates. Pediatr Dermatol. 1986 Feb;3(2):140-4. [PubMed: 3952030]

14.

Goyal T, Varshney A, Bakshi SK. Incidence of Vesicobullous and Erosive Disorders of Neonates: Where and How Much to Worry? Indian J Pediatr. 2021 Jun;88(6):574-578. [PubMed: 22037857]

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SANDERSON PH, SLOPER JC. Skin disease in the British army in S. E. Asia. I. Influence of the environment on skin disease. Br J Dermatol. 1953 Jul-Aug;65(7-8):252-64. [PubMed: 13059235]

16.

Mowad CM, McGinley KJ, Foglia A, Leyden JJ. The role of extracellular polysaccharide substance produced by Staphylococcus epidermidis in miliaria. J Am Acad Dermatol. 1995 Nov;33(5 Pt 1):729-33. [PubMed: 7593770]

17.

Kravvas G, Veitch D, Al-Niaimi F. The increasing relevance of biofilms in common dermatological conditions. J Dermatolog Treat. 2018 Mar;29(2):202-207. [PubMed: 28749746]

18.

Dixit S, Jain A, Datar S, Khurana VK. Congenital miliaria crystallina – A diagnostic dilemma. Med J Armed Forces India. 2012 Oct;68(4):386-8. [PMC free article: PMC3862747] [PubMed: 24532912]

19.

LUBOWE II, PERLMAN HH. Periporitis staphylogenes and other complications of miliaria in infants and children. AMA Arch Derm Syphilol. 1954 May;69(5):543-53. [PubMed: 13147561]

20.

Mohanan S, Behera B, Chandrashekar L, Kar R, Thappa DM. Bull’s-eye pattern in miliaria rubra. Australas J Dermatol. 2014 Nov;55(4):263-5. [PubMed: 23808709]

21.

Tey HL, Tay EY, Cao T. In vivo imaging of miliaria profunda using high-definition optical coherence tomography: diagnosis, pathogenesis, and treatment. JAMA Dermatol. 2015 Mar;151(3):346-8. [PubMed: 25390622]

22.

Kirk JF, Wilson BB, Chun W, Cooper PH. Miliaria profunda. J Am Acad Dermatol. 1996 Nov;35(5 Pt 2):854-6. [PubMed: 8912605]

Disclosure: Karla Guerra declares no relevant financial relationships with ineligible companies.

Disclosure: Alicia Toncar declares no relevant financial relationships with ineligible companies.

Disclosure: Karthik Krishnamurthy declares no relevant financial relationships with ineligible companies.

Symptoms, treatment, appearance, and causes

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Heat rash — also known as prickly heat, summer rash, or wildfire rash — happens when the sweat gland ducts become blocked. Triggers include exercise and hot weather. Cooling or gently patting the rash may provide some relief.

The medical name for heat rash is miliaria. It happens when sweat becomes trapped due to a blockage in sweat glands in the deeper layers of skin.

Inflammation, redness, and blister-like lesions can result. Sometimes, an infection can develop.

People with overweight or obesity and people who sweat easily are more likely to get prickly heat. Also, babies and children are more prone to it because their sweat glands are still developing.

Symptoms include:

• small bumps or spots, called papules.
• an itching or prickling sensation
• mild swelling

On white skin, the spots are red.

On darker skin, they can be harder to see, but if a doctor uses dermoscopy — a kind of lighted microscope for examining the skin — the spots may show up as white globules under the skin with darker halos surrounding them.

Heat rash often affects areas where sweating is more likely, including the:

• face
• neck
• under the breasts
• under the scrotum

It can also appear in skin folds and areas where skin rubs against clothing, such as the back, chest, and stomach.

If bacteria enter the plugged sweat glands, it can lead to inflammation and infection.

Why do some people sweat more than others?

Heat rash often goes away on its own within about 24 hours.

To help it resolve, move to a cool area with less humidity, if possible, and remove any clothing and other items that may increase sweating.

Other tips include:

• Wear light, loose cotton clothing.
• When exercising, choose a cool place or a cooler time of the day.
• Use showers, fans, and air conditioning to reduce the body’s temperature.
• Avoid any irritants that make symptoms worse, such as some synthetic fabrics.
• Avoid staying in wet clothing, such as after swimming.
• Apply a cool compress, such as a damp cloth or an ice pack wrapped in a towel, to the rash for up to 20 minutes at a time.
• Use light bedding.
• Drink plenty of fluids, preferably water, to prevent dehydration.
• If the rash is itchy, tap or pat it instead of scratching it.

Here, learn about home and natural remedies for heat rash.

Some over-the-counter preparations can help soothe and resolve persistent heat rash. They include:

• Topical preparations — such as calamine, menthol, and camphor-based creams or ointments — can help ease the itching. Use an emollient with calamine, however, as it can dry the skin.
• Steroid creams can reduce itching and inflammation in people aged over 10 years.
• Antibacterial products can help manage or prevent an infection.

Some of these products are available online. Antibacterial handwash is also available for purchase online.

There are three types of heat rash, or miliaria:

Miliaria crystalline: This is the most common form. It causes small, clear or white bumps filled with sweat to form on the skin’s surface. The bumps measure 1–2 millimeters across. It causes no itching or pain and is more common in babies than adults.

Miliaria rubra: This type is more commonly known as prickly heat, and it causes larger bumps, inflammation, and a lack of sweat in the affected area. It occurs in deeper layers of skin and is more uncomfortable. If the bumps fill with pus, the medical name becomes miliaria pustulosa.

Miliaria profunda: This is the least common type of heat rash. It forms in the deepest layer of skin, and it can recur and become chronic. It causes relatively large, tough, flesh-colored bumps.

Heat rash, or miliaria, happens when sweat gland ducts become blocked.

This may be due to:

• sweat glands still developing, as in newborns
• a hot and humid environment
• physical activity
• a fever
• wearing synthetic fabrics close to the skin
• wearing a nonporous bandage
• prolonged bed rest
• the use of some medications, especially those that reduce sweating
• radiation therapy
• some health conditions, such as toxic epidermal necrolysis

Heat rash usually disappears without treatment. However, see a healthcare provider if:

• the rash persists or becomes more severe
• there are signs of an infection, such as open blisters or pustular lesions
• there are signs of heat exhaustion and an inability to sweat
• there are other symptoms, such as a fever

Many illnesses cause rashes, which may look similar to heat rash. A doctor can determine the underlying cause.

Learn about the many other types of rash and their causes.

Heat rashes are not often dangerous, but if symptoms last longer than a few days or signs of an infection appear, see a healthcare provider.

They will examine the rash, possibly using dermoscopy for a closer inspection.

If necessary, they may also take a skin punch biopsy or use imaging technology to identify the cause of the rash.

Skin changes are a common symptom of many conditions. Heat rash can resemble other health issues, including:

• viral infections, such as chickenpox or measles
• bacterial infections, such as impetigo
• hives, due to an allergic reaction
• fungal skin infections, such as candidiasis
• insect bites
• folliculitis, due to a blockage in hair follicles
• acute HIV
• a response to HIV treatment

If any of the following symptoms occur, they may indicate that the cause of the rash is more serious:

• a fever
• a cough
• a runny nose
• fatigue
• enlarged lymph nodes
• muscle aches

To reduce the risk of prickly heat or heat rash, try to:

• Avoid activities or locations that increase sweating.
• If possible, use air conditioning or a fan.
• Wearing light clothing made from natural fibers, such as cotton.
• When possible, minimize exposure to hot and humid weather.
• Gently exfoliate the skin to remove dead skin cells and sebum that may clog the sweat glands.
• Take cool showers frequently and be sure to pat the skin completely dry.

Exfoliators are available online.

Heat rash is common, especially among babies and anyone in a hot, humid climate.

It usually goes away without treatment, although home remedies can help ease the rash and relieve any discomfort.

If heat rash seems to be involving deeper layers of skin, if there are signs of infection, such as blisters, or if it just lasts for more than a few days, seek medical attention.

Many health issues can cause rashes that resemble heat rash, so if a person has other symptoms, such as a fever, it is important to receive a diagnosis.

Temperature urticaria.

What is Temperature Urticaria?

IMPORTANT
The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.

Temperature urticaria – allergic urticarial dermatosis that occurs as a response to the action of the temperature factor. The main clinical symptoms are itching and hyperemia, against which monomorphic blisters appear that last no more than 24 hours. Rashes may be accompanied by fever, headache, prodromal phenomena, intoxication. Temperature urticaria is diagnosed on the basis of anamnesis, clinical manifestations and provocative tests. Therapy consists in eliminating the cause of dermatosis, prescribing antihistamine, desensitizing, anti-inflammatory drugs, detoxification.

• Causes of temperature urticaria
• Classification of temperature urticaria
• Symptoms of temperature urticaria.
• Diagnosis of temperature urticaria
• Treatment of temperature urticaria
• Prices for treatment

General information

Urticaria is a transient allergic response of the body to heat or cold. This pathology affects about 7% of the world’s population. For the first time, temperature urticaria is mentioned in the writings of Hippocrates (4th century BC). The clinical symptoms of the disease were described in detail in the 18th century by the English physician W. Heberden. The discovery of mast cells overflowing with histamine by the German immunologist P. Ehrlich in 1877-79years gave the basis for understanding the pathogenesis of urticaria in terms of the formation of urticaria. In 1961, representatives of the Russian school of dermatology Yu. F. Antsypalovsky and A. P. Zinchenko proved the priority in the pathogenesis of cold urticaria of special cold receptors that are hypersensitive to low temperatures, which, combined with the allergic mood of the body, explained the fact of the undulating course of the pathology and its resistance to ongoing therapy.

Temperature urticaria has no gender and age limits. The non-standard nature of this condition is manifested in its ability to accompany the process of warming a person, to occur during summer rain, swimming in tropical latitudes, moving from sunshine to shade, etc. The urgency of the problem at the present stage is associated with a steady increase in the incidence of temperature urticaria, as well as with industrial and economic losses, since dermatosis affects mainly able-bodied patients.

Temperature urticaria

Causes of temperature urticaria

Thermal or cold exposure is considered the starting point of the disease. Thermal urticaria is a contact dermatosis, cold urticaria occurs as a reaction of cold skin receptors to a decrease in ambient temperature, the use of ice cream and cold drinks. In addition, this condition can be observed with intravenous administration of drugs whose temperature is below 6 ° C. Sometimes the pathological process is a symptom of other diseases associated with the presence of cold-dependent proteins in the patient’s body (for example, paroxysmal cold hemoglobinuria). Factors that increase the likelihood of developing temperature urticaria are parasitic diseases, colds, foci of focal infection in the patient’s body, diseases of the digestive tract, and gynecological pathology. There are hereditary autosomal dominant forms of temperature urticaria.

There is no unified concept of the occurrence of pathology. There are immune and non-immune mechanisms of development of temperature urticaria. When exposed to low temperatures on the skin, activation of mast cells occurs, from which histamine, prostaglandins, leukotrienes (LT D4, C4, E4) are released, vascular permeability increases with the development of edema and the appearance of blisters. In parallel, the body begins to produce special proteins – cryoglobulins, which additionally stimulate the production of histamine and provoke new allergic rashes.

Rarely, passive transfer of hypersensitivity to cold mediated by IgG or IgG-IgM cryoglobulins has been reported. Exposure to cold stimulates the synthesis of IgG autoantibodies to mast cell-associated receptors. Circulating immune complexes are formed, provoking a vascular response similar to the histamine response with protein cell destruction and blistering. Thermal urticaria is caused by the release of acetylcholine mediators from nerve endings under the influence of heat.

Classification of temperature urticaria

In modern dermatology, there are two main forms of temperature urticaria – cold and heat. Cold urticaria occurs as a response of the skin to low temperatures. It can be acute (up to 6 weeks) or chronic (more than 6 weeks). Thermal urticaria, which develops in response to high temperatures, is also divided into acute (up to 6 weeks) and chronic (more than 6 weeks).

Cold urticaria includes the following pathologies:

• Recurrent – seasonal (summer months and late spring are excluded), arising from the action of cold water.
• Reflex – local, manifested by a rash around the place of contact of the epidermis with cold, and general, arising from hypothermia of the whole organism. The contact area remains unchanged.
• Familial – genodermatosis with autosomal dominant inheritance.
• Cold erythema, accompanied by painful hyperemia in the area of ​​​​contact of the skin and cold.
• Cold dermatitis is a scaly inflammation of the skin in response to hypothermia.
• Cold rhinitis, characterized by coryza symptoms only in the cold.
• Cold conjunctivitis, manifested in the cold.

Heat urticaria includes two varieties:

• The classic local form that occurs at the point of skin contact with heat.
• A non-standard cholinergic form is a variant of the development of a pathological process in response to heat during physical exertion, stress, hot baths, hot weather.

Symptoms of temperature urticaria.



The main feature of the disease is the monomorphism of rashes and itching. Blisters are localized everywhere, including the skin of the hands, feet, scalp. The size and appearance of the elements vary considerably – from bubbles a few millimeters in diameter to palm-sized confluent elements resembling a geographical map with their outlines. The acute form of temperature urticaria is characterized by large blisters that rapidly appear and then just as quickly regress, the chronic form is characterized by a small rash that persists on the skin for a day. Chronic temperature urticaria is an intensely itchy nocturnal dermatosis, which is due to the daily rhythm of histamine secretion. In acute temperature urticaria, itching is less intense, absent at night.

Temperature urticaria begins spontaneously with itching and hyperemia. Against the background of erythema, bright pink urticaria appear, edema increases, which compresses the capillaries of the skin, as a result of which the blisters turn pale. Hemorrhagic rashes are possible. Subsequently, the blisters begin to regress from the center, taking the form of rings. With the development of recurrence or chronicity of temperature urticaria, prodromal phenomena are noted with a sharp rise in temperature, arthralgia and dyspepsia. Temperature urticaria is capable of self-regression, leaves no marks on the skin. Anaphylactic reactions are very rare.

Diagnostics of temperature urticaria

Clinical diagnosis is made by a dermatologist on the basis of anamnesis and rash monomorphism, confirmed by provocative tests. For the cold version, the Duncan test is used: ice is placed on the elbow, if after 15 minutes the skin remains inert, there is no urticaria. For a more accurate check, immersion is used by immersing the hand in cold water (below 8 ° C) for 5-10 minutes. The absence of itching and erythema during the test time is a negative result. You can place the patient without clothes for 10-30 minutes in a cold room at a temperature of 4 °C. In this case, care should be taken to avoid the development of a cold or systemic reactions. An exercise test at 4 °C for 15 minutes is also used, after which the level of cryoglobulins in the blood is determined.

The local form of heat urticaria is diagnosed using a test with a warm object: a glass of hot water (40-48 °C) is applied to the skin of the forearm for 1-5 minutes or a hand is dipped in water of the same temperature. The inertness of the skin indicates the absence of urticaria. The advanced form is confirmed by the occurrence of blisters in a hot bath at a temperature of 40-48 ° C or by walking for 30 minutes. Heat urticaria of the cholinergic variant can also be diagnosed by a skin test with methacholine (blisters with intravenous or subcutaneous administration of the substance). To exclude a different genesis of blisters, a blood test for allergens is performed.

Differentiate temperature urticaria with insect bites, dermographism, urticarial vasculitis, exudative erythema multiforme, strophulus, hereditary angioedema, mastocytosis, secondary syphilis, Leffler, Wissler-Fanconi, Melkersson-Rosenthal syndromes.

Treatment of temperature urticaria

It is necessary to eliminate the cause of the disease. With cold urticaria, a combination of antihistamines of the II and III generation, tranquilizers, desensitizing agents, M-anticholinergics is shown. In severe cases, corticosteroids are prescribed in short courses, detoxification is carried out. Anaphylaxis requires immediate intravenous or subcutaneous adrenaline. You can stop the attack on your own with the help of a special pen-syringe with adrenaline. Local therapy includes warm oatmeal baths, antipruritic and anti-inflammatory drugs, talkers.

In the heat setting, antihistamines are ineffective due to acetylcholine mediators. Gels and ointments based on atropine, belladonna extract are applied to the lesions 1-2 times a day. In parallel, they stop the exacerbation of concomitant diseases, sanitize the foci of chronic infection. The prognosis is relatively favorable, in 50% of cases, temperature urticaria spontaneously resolves within a year. In 20% of patients, the pathology becomes chronic, acquires a persistent relapsing course. Timely and accurate diagnosis, adequate therapy are important, since temperature urticaria in rare cases is complicated by angioedema and anaphylaxis.

Sources

1. treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.

   Summer and its consequences. Doctors told how to protect yourself from seasonal allergies and sunstroke0001

   The long-awaited summer season for Yakutians has come, when you can spend more time outdoors, enjoy the sun and stock up on vitamins before the long winter. At the same time, summer is the time of seasonal allergies, as well as hot days that bring heat and sunstroke. About how to deal with seasonal allergies, how heat stroke and sunstroke differ, how to avoid them and how to help with the first symptoms, the YSIA correspondent talked with allergist-immunologist Yana Pakhomova and Maria Antonova, instructor in physiotherapy exercises at the Department of Medical Prevention of the Republican Clinical Hospital No. 3.

   When the plants start flowering, signs of seasonal allergies also appear: watery eyes, sneezing, stuffy nose… What causes allergies? How easy is it to survive? What to do with the first symptoms, said Yana Pakhomova, an allergist-immunologist of the Republican Clinical Hospital No. 3 .

   — Yana Arturovna, please tell us what causes seasonal allergies? When do periods of exacerbation occur?

   — Allergic diseases can be year-round and seasonal. To the spring seasonal allergy can be attributed an allergy to tree pollen – hay fever. In our republic, this is the flowering of birch, which falls on the period from the 20th of May to the end of June. In this case, allergy symptoms are disturbing at the same time of the year. At this time, people with allergies develop a runny nose, bouts of sneezing, copious discharge from the nose, itching, redness of the eyes, coughing, itchy palate, wheezing, shortness of breath, and suffocation. In addition, there may be skin manifestations – itching, rash, swelling.

   — How allergic is Yakutia compared to other regions of Russia?

   — Yakutia does not differ much from other regions in the incidence of allergic pathology. But still, it has its own specifics – it’s a cold and long winter, we wear a lot of fur, we are more in a room where the air is very dry due to heating. All these factors, of course, affect the incidence. Summer is short, but our republic is rich in flora, all the main plants that cause pollinosis grow and bloom – this is birch, a variety of cereals and weeds, including wormwood. Therefore, in summer, especially if there is little rain, allergy sufferers suffer.

   — Tell us what to do at the first allergy symptoms? If you can’t get to the doctor, what should you do at home?

   – The first step in the treatment of any allergy is to try to remove (eliminate) the causative allergen, that is, avoid contact with pollen. I also advise you not to go out of town, agricultural work is prohibited, you don’t need to open the windows in the apartment, in the car, in the office, after returning from the street you need to take a shower, change clothes. In addition, it is important to carry out wet cleaning daily, use an air purifier around the clock. The second stage of treatment is allergen-specific immunotherapy (ASIT) with a causative allergen (tree, grass pollen). It is necessary before the flowering season, in winter and early spring, to receive a therapeutic allergen from the pollen of trees, herbs in an allergy room. The third stage of treatment is medication. Symptomatic therapy is prescribed – tablets, drops, sprays, ointments, inhalations for allergy symptoms.

   — How not to confuse allergy symptoms with other diseases?

   – Yes, there are some peculiarities here. Firstly, skin manifestations of allergies – rash, itching, swelling must be distinguished from many skin diseases. Secondly, respiratory manifestations of allergies – runny nose, sneezing, itchy eyes, coughing, shortness of breath, wheezing – from infectious diseases. But I note that with allergies, body temperature does not rise, well-being is not disturbed, as with acute respiratory diseases.

   Another of the unpleasant and dangerous phenomena on hot summer days is sun and heat stroke. In the coming days, weather forecasters predict an increase in air temperature to +30 degrees and above. Of course, excessive exposure to the sun is harmful to everyone. How to prevent sunstroke and how to provide first aid, told the instructor in physical therapy of the Department of Medical Prevention of the Republican Clinical Hospital No. 3 Maria Antonova.

   — Maria Nikolaevna, please tell us what heat stroke and sunstroke are? Why are they dangerous to health and what are the symptoms?

   – These days we will have up to 30 degrees. With the establishment of elevated atmospheric air temperature, some people may experience discomfort. For example, increased irritability, aggressiveness, frequent fears, sudden mood swings, and insomnia may appear.

   Heat stroke is a violation of the body’s vital functions associated with overheating. Heatstroke is accompanied by drowsiness, headache, general weakness, dizziness. If further overheating is not prevented, the face begins to turn red, the body temperature can rise up to 40 degrees, vomiting and diarrhea may join. I note that if the cause of overheating is not eliminated, the victim may begin delirium, then loss of consciousness, the face turns pale, the skin becomes cold, the pulse quickens. In such a situation, an ambulance should be called urgently.

   Sunstroke is a severe morbid condition, disorder of the brain due to prolonged exposure to direct sunlight on the uncovered surface of the head. This particular form of heat stroke is characterized by receiving more heat than the body can cool. In this case, not only sweating is disturbed, but also blood circulation, blood vessels dilate, blood stagnation in the brain can occur – this is extremely dangerous! Sunstroke is accompanied by headache, lethargy and vomiting. The consequences of such a blow can be very serious – up to cardiac arrest.

   Factors that contribute to heat and sunstroke are direct exposure to the sun on a bare head, overweight, obesity, stress, tension and obstruction to heat dissipation. That is, you should not wear too tight clothes and poorly ventilate the premises. And also cardiovascular and endocrine diseases, neurological problems, and the state of alcoholic intoxication matter.

   It is worth noting that a severe form of sunstroke develops suddenly. It occurs if a person is in direct sunlight for a very long time without a hat. In this case, the skin becomes cyanotic, there may even be hallucinations, convulsions, an increase in body temperature up to 41 – 42 degrees, even a coma or sudden death is possible. Therefore, at the slightest symptom, it is necessary to call a doctor.

   — Who is most susceptible to sunstroke?

   — Hot weather has a negative impact on the health of the population of all age groups. Particularly affected are persons with chronic diseases of the cardiovascular system, the elderly and children. The number of patients with high blood pressure, acute cerebrovascular accident, myocardial infarction is also increasing.

   — How to provide first aid for sun and heat stroke?

   – The most important thing is to move the victim to a shaded or cool place where there is enough oxygen and a normal level of humidity. The victim must be put down, while the head and legs must be raised, free him from outerwear, belt, buttons. It is necessary to drink plenty of cool water, but mineral water is better, in which you can add a little sugar and salt at the tip of a teaspoon. You also need to moisten with cold water, apply a cold wet cloth to the forehead and neck. If there are no cold foods or drinks nearby, you can take frozen food straight from the freezer and wrap it in a napkin or towel, and then apply it to the head, under the back of the head and on the forehead. It is necessary to fan the victim with frequent movements so that there is air circulation.

   If involuntary vomiting occurs, clear the airway of vomit and turn slightly on its side so that the person does not suffocate. In case of respiratory distress and a cloudy state, ammonia should be smelled.

   Let me emphasize that these days, more than ever, first-aid kits should have ammonia and soothing heart drops, especially for those who have elderly people with chronic cardiovascular diseases and small children in their families.

   I will also note that if you are somewhere in the forest, for example, or, in general, far from your place of residence, in such emergency cases as fainting or respiratory arrest, you do not need to wait for the help of a doctor – you need to give artificial respiration to the victim and heart massage until respiratory movements and cardiac activity will not appear.

   But once again, be sure to call a doctor if you have any symptoms.

   — What is strictly forbidden if a person has received sun or heat stroke?

   – Never leave him in the place where he received sunstroke, especially on the field, on the street. It is necessary to quickly transfer it to a cool room and give cool water.

   — Advise on how to prevent sun and heat stroke?

   — On hot days, it is necessary to observe the drinking regime. Drink more water, for example, if you drink 2 liters, increase to 2.5 – 3 liters per day. From 12 to 4 o’clock it is necessary to protect all parts of the body from sunlight, wear light, breathable clothing, preferably made of cotton or linen, as well as a hat. It is strictly forbidden to drink alcohol, which can lead to a general deterioration in the state of the body. Minimize even the use of decorative cosmetics, because our skin breathes hard and sweats in the heat, thereby lowering our body temperature, and clogging of pores with cosmetics can lead to overheating of the body.