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Causes rash
contents
- Rash in infectious diseases
- chickenpox
- Measles and rubella
- scarlet
- syphilis
- Rash due to allergic reactions
- Cause eczema
- Itching skin lesions due to fungal infections
- Other causes of itchy rash
- shingles
- psoriasis
- drug incompatibility
- parasites
- sunlight
- Rash due to fluid retention in tissue
Rash in infectious diseases
Various infectious diseases lead to an itchy rash, which may differ significantly depending on the diseases in its efflorescence and the concomitant symptoms. Measles, rubella, scarlet fever, chickenpox and syphilis are some of the most common infectious diseases that cause an acute rash.
Chickenpox is one of the most common childhood diseases and is highly contagious. Characteristic of the viral disease is an itchy rash with red-rimmed blisters. (Image: meryll / fotolia.com) chickenpox
Shortly after infection, the chickenpox caused by the varicella-zoster virus causes a skin rash with red-edged, itchy blisters especially in the area of the trunk, face and scalp. In the later course of the disease, the skin change also reaches the limbs. Over time, the bubbles burst and release a light liquid. Subsequently, a light brown crust forms, which dissolves in the further course of the skin.
The varicella-zoster viruses remain after surviving disease in the organism and may cause later in life a shingles (herpes zoster). This manifests itself in an itchy, painful rash with increased blistering, which occurs locally limited mostly in the chest, back, arms or legs. Again, the bubbles burst after some time and released the liquid contained. The viruses can be transmitted through contact with the liquid, so care must be taken.
Measles and rubella
In measles, the rash usually sets in later in the disease, begins behind the ears and then covers the whole body with a reddish spotty-nodular structure. It can also show relatively large contiguous red spots. Usually, the irritations are not accompanied by itching and disappear after five days at the latest. Occasionally, dandruff will be visible on the skin for some time afterwards.
With the healing of skin lesions and dandruff may occur an increased scratching need. In addition to the rash, measles virus infection typically causes symptoms such as runny nose, airway inflammation, conjunctivitis, high fever, sore throat, headache, nausea, and vomiting.
In the case of measles, the healing of the rash can be accompanied by an increased need for itching. (Image: miamariam / fotolia.com) In rubella, the rash is similar to that in measles, but with smaller patches and in conjunction with additional concomitant symptoms. These include, for example, painful lymph node swelling or joint inflammation in particularly severe disease.
scarlet
Scarlet fever is a bacterial infectious disease caused by certain streptococcal bacteria, which occurs mainly in children. A few days after the onset of the disease, a characteristic rash appears with closely spaced, distinctly reddish spots the size of a pinhead. Often this occurs locally in the armpits or groin, but can also affect the whole body. Typically, the area around the mouth remains unaffected, even if the rash otherwise spreads across the face.
Characteristic of the common childhood disease are also a shiny red tongue coating and protruding taste buds ("raspberry tongue"). About two weeks after the onset of the disease, the skin begins to develop more dandruff, especially in the area of the palms, fingers and toes and under the feet.
Even with scarlet fever, the rash usually runs without itching, but the detachment of the skin may be accompanied by a slight itching. The concomitant symptoms of the disease include sore throat, fever, chills, pharynx and tonsillitis.
syphilis
Syphilis is caused by bacteria, which can be transmitted especially during sexual intercourse. The bacteria cause in the initial stage of the disease, where they have penetrated into the skin or mucous membrane, a reddish ulcer, which in advance remains mostly painless and secretes an aqueous liquid.
Several weeks after the infection, those affected show flu-like symptoms such as fever, headache and body aches. At the same time, the lymph nodes swell all over the body and it develops a moderately itchy rash, with papillate, pale pink spots. The skin damage usually heals after a few months again, but return in case of failure to provide medical care at irregular intervals.
Since some of the mentioned infections can at worst have life-threatening consequences, medical advice should be sought immediately in case of itchy skin irritations accompanied by accompanying symptoms.
Rash due to allergic reactions
Often the symptoms are caused by allergies, with a distinction between immediate allergic reactions to contact with certain substances and delayed reactions. Some people, after exposure to special allergens, such as certain shower gel or shampoo ingredients, experience a severe reaction on the skin that includes redness, swelling, hives, and intense itching.
An allergy, e.g. to certain ingredients of care products, can lead to severe itchy rash. (Image: gamelover / fotolia.com) In others, the allergy may develop over a long period of time through constant contact with substances before obvious skin reactions with itchy rash follow. Affected persons are sensitized in the long term by the regular handling of the substances and then react allergically. If contact with the allergens is not prevented, a chronic rash develops, which can lead to significant impairment of the quality of life and other health problems.
The allergic skin reactions are roughly divided into two distinct categories: hives and contact dermatitis, where hives tend to be more likely to be acute and contact dermatitis is a delayed allergic reaction.
The most common triggers of the allergy rash include nickel, chromium, formaldehyde, mercury compounds (for example in vaccines) and special ingredients (eg, Peru balsam, Quaternium 15) from perfume, lotions, shampoo, nail polish or other cosmetic products.
In addition, there are disinfectants, plastics, adhesives, paints, paints, glues, turpentine, pesticides, epoxy resins, detergents and many other substances, which may result in regular contact with sensitization with subsequent allergic reactions and itchy skin lesions.
Furthermore, spices and baking agents should be mentioned as more frequent triggers. Since those affected usually come in contact with the substances in their professional lives and can not be completely avoided even if additional precautionary measures are taken, a life-long occupational disability can be imminent here.
Cause eczema
In eczema (atopic eczema) is the reddish, often itchy rash one of the main symptoms of disease. The sufferers suffer from extremely sensitive dry skin, which tends to develop eczema both through mechanical influences (clothing, sweating) as well as through certain foods and allergic reactions to house dust, pollen or animal hair.
The natural skin flora is significantly disturbed in atopic dermatitis, making it more susceptible to the colonization of bacteria and fungi. As a result, further deterioration of the skin condition are possible. Atopic dermatitis often progresses in spurts, whereby periods of severe skin irritation may be followed by relatively symptom-free periods. Reddening and swelling of the skin as well as oozing and corresponding crust formation are typical.
Most of the armpits, armpits, knees, neck or face are affected. The itchy rash of atopic eczema can also spread throughout the body. If the damage to the skin is not taken care of, there is also a threat of bacterial infection. Over time, the skin of eczema patients is permanently damaged in their structure and shows the typical Lichenifikation (thickening of the epidermis).
Atopic dermatitis means a strong physical and psychological burden for most of those affected. (Image: casi / fotolia.com) The skin problems in atopic dermatitis are related to mental health problems of those affected. Psychosomatic disorders are reflected in the complexion and the obvious disorders of the skin can in turn become a psychological burden on patients (reduced self-esteem). In addition, the nocturnal itching often causes a significant sleep deficit, which can also have negative consequences for the psyche of the patients. Those affected often suffer from lack of concentration, are constantly irritated and struggle with chronic fatigue.
Itching skin lesions due to fungal infections
Various skin fungus diseases (dermatomycoses) cause a reddened, scaly and itchy rash. So-called filamentous fungi (dermatophytes) and yeasts (candida) are the most common cause of the complaints. The infection is usually limited to the upper layers of the skin, but can also penetrate into deeper layers through injuries to the skin.
Danger: Scratching is therefore to be avoided as far as possible even with severe itching. This is even more so, since the fungi can be transferred after scratching on the fingers to other body regions or people.
The dermatophytes are transmitted by direct or indirect contact with the fungal spores. The infection is limited to keratinous tissue such as hair, nails or the horny layer of the skin. If the fungal spores have overcome the natural barriers of the organism, thread-like fungal cells grow out of the spores. Carriers are often by domestic animals and livestock, the fungi often cause little discomfort with their original hosts.
In humans, however, complications often occur due to an overreaction of the immune system and corresponding allergic reactions. The allergic reactions triggered by chronic dermatophytoses are also considered to be a contributing factor to the development of asthma.
In principle, fungal infections can occur almost on the entire skin surface, whereby a differentiation is often based on the localization. Accordingly, dermatophytoses on the feet are referred to as foot fungus (Tine pedis), on the hands as Tinea manus and on the face as Tinea facies. However, the localization of the infection does not allow any conclusions about the exact pathogens that led to the disease.
Furthermore, yeasts can cause an infection of the skin that results in red itchy rashes. Yeasts are a component of the natural skin flora, but if this gets out of balance, it can sometimes lead to a pathological proliferation. The result is a candidosis (yeast fungus disease), which can affect not only the skin and mucous membranes in people with weakened immune systems, but at worst also on the internal organs.
If the yeast infection only affects the skin or mucous membranes, it is also referred to as thrush. In this case, various fungi of the genus Candida cause a red itchy rash on the skin surface with pustules, blisters and dandruff. Often the genital area is affected.
Other causes of itchy rash
In addition to the causes shown, numerous other triggers of the complaints come into consideration. These range from late effects of infectious diseases to drug intolerances and intense sunshine to infestation with parasites or psychosomatic illnesses.
Even a short skin contact with poisonous plants such as the Hercules shrub can cause severe inflammation, redness and itching. (Image: Martina Berg / fotolia.com) Contact with certain (poison) plants or animals may also cause an itchy rash. These include, among others, the caterpillars of the oak processionary moths and the Hercules shrubs, which are also known under the name "Giant Bear Claw". This spreads for some years more and more in foreign areas and displaces the native flora, which is why plants in botany as "invasive neophyte" is called.
Experts warn again and again that the giant bear claw is a health hazard for children, when they come into contact with the unknown poisonous plant. Because certain substances in the juice of the perennial can cause severe burns in combination with UV radiation. Usually a short contact is enough to cause itching, redness and blisters. In severe cases, fever, sweating and circulatory problems can occur in parallel to the skin irritations.
shingles
The shingles (also called "herpes zoster" or "zoster" for short) is the result of an infection with chickenpox viruses (varicella-zoster viruses). The pathogens usually remain inactive in the body after a surviving illness in childhood and years later cause the painful viral disease. Herpes zoster is always the result of the reactivation of existing in the organism Varicella zoster virus, which usually comes to bear only when weakening the body's defenses. Causes of the immune deficiency can be for example stress, a high age as well as illnesses of the immune system.
Shingles on the skin show a very itchy, partially painful, red rash. The skin surface is covered with blisters in the affected area. These can easily burst and release virus-laden fluid, which can also cause an infection in people. Primary infection usually causes chickenpox in healthy people. The itchy rash on shingles is often limited to the area of the rib cage, back, flanks, arms or legs.
Most of the herpes zoster heals after a maximum of one month by itself again. One in five patients, however, is struggling with complications that, at worst, last a lifetime. In immunocompromised individuals, inflammation of the meninges or spinal cord may occur. Not infrequently, the affected suffer from paralysis of the peripheral nerves, which, however, usually disappear again. Typically, even before the onset of skin symptoms, there is severe pain in the area of spread of the affected nerve tracts. These so-called Zosterneuralgies may persist even after the skin has healed.
In particularly severe disease, sometimes the entire nervous system is affected, which can have life-threatening consequences for patients. Shingles also occasionally appear as a very itchy rash in the genital area, which in some patients extends to the area of the thigh.
psoriasis
Psoriasis (psoriasis) usually manifests as a skin disease that causes reddish, often roundish, localized, severe scaling skin irritation that may be associated with severe itching. Most psoriasis occurs on the knees, elbows, on the scalp or around the navel. It is not contagious, but it can spread to other organs.
Due to a disturbed skin renewal process, dandruff forms on the skin, which peel off easily and make the strongly perfused, reddish border appear to the dermis recognizable. Under certain circumstances, in the course of the disease also lower cell layers dissolve, which may be accompanied by slight bleeding. For many people, skin lichen is less of a physical burden than a psychological burden. Their self-esteem is affected, they feel socially isolated and prone to depression, according to previous scientific findings.
drug incompatibility
Itchy rash may be due to drug intolerance. This so-called drug eruption is caused by the intake or local use of drugs. In the course of a drug allergy, the rash appears as an undesirable side effect of the drugs. He may resemble the appearance of various infectious diseases such as measles or scarlet fever.
The most common triggers of drug eruption include antibiotics, analgesics, and antiepileptic drugs. In principle, however, any drug can cause a corresponding allergic reaction. In order to avoid the itchy skin lesions and other health impairments, the suspected drug should be discontinued as soon as possible and possibly substituted by other preparations.
In addition to medicines, cosmetics sometimes cause unwanted side effects that are accompanied by skin irritation and itching. The most well-known example is the so-called Periorale Dermatitis, a rash in the face, which is triggered by the excessive use of cosmetics.
parasites
As a trigger different parasites are considered. However, most of them are not common in Germany and can only appear as an unpleasant holiday gift. The so-called cercaria (larvae of sucking worms) also occur in this country and cause the so-called bath dermatitis in humans. The nematode larvae living in lakes and ponds penetrate the upper layers of the skin, but can not multiply here and subsequently die. The result is redness of the skin in the affected area, associated with wheals and severe itching.
The cercaria are actually adapted to waterfowl as hosts and therefore can not survive in the human organism. Their penetration into the skin, however, is sufficient to cause significant reactions on the skin. This is usually relatively harmless in the first infestation, but is often associated with a renewed penetration of the cercaria with massive disturbances of the skin surface. The itchy rash is usually over in a bath dermatitis after about two weeks.
Furthermore, the mites caused by mites (medical: scabies) come into consideration. The females of the tiny arachnids drill passages into the epidermis and lay their eggs there. From this, larvae hatch within two to three days, which after three weeks of growth provide as sexually mature itch mites for further offspring. Thus, the tiny animals can multiply massively within a short time and affect large areas of the skin.
The left behind faeces of the scabies mites cause a kind of allergic reaction, which causes a violent itchy rash with blisters, pustules, wheals, subsequent encrustation and dandruff. In most cases, the skin disease is concentrated on the fingers, wrists, buttocks, genitals or skin folds of the elbows, armpits and popliteal fossa. Scabies is one of the notifiable diseases in Germany.
UV rays can trigger photodermatosis. In this case, some time after staying in the sun, a red skin rash, blisters and severe itching occur. (Image: Andrey Popov / fotolia.com)sunlight
Excessive sunbeams cause an itchy rash in some people, referred to in the art as photodermatosis. In principle, a sunburn is to be understood as a special form of dermatitis. The sensitivity to sunlight is extremely different depending on the skin type. Under certain circumstances, photodermatosis in bright skin types may develop under relatively low sun exposure.
Often the symptoms appear in early summer on first intensive contact with the sun's rays. The consequences are skin irritations that can take different forms individually. Many sufferers suffer from itchy rashes, which can vary significantly from patient to patient in terms of redness, blisters, nodules, dandruff and fluid secretion. In relation to the individual affected, however, the symptoms over the years are always consistent.
Rash due to fluid retention in tissue
Fluid deposits in the tissue can lead to itching skin irritation, which is referred to medically as so-called congestive dermatitis. Impaired blood circulation such as venous insufficiency often causes thick legs and swollen feet, which in turn can cause permanent skin damage.
The lack of blood flow to the tissue often causes a skin rash, the worst in the long run, the formation of inflammatory ulcers and ends in a death of the tissue. The stasis dermatitis should be taken seriously as a warning sign of possible circulatory disorders and examined by a specialist.
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Itchy rash
Specialist supervision: Barbara Schindewolf-Lensch (doctor)