Definition
A single or planar skin irritation is called exanthema. Depending on the location, it is called abdominal, trunk or even back exanthema. Skin problems in the area of the back are relatively common.
The duration of the complaints can range from a few hours to even days or weeks. The skin is the largest organ of the body. It represents the natural barrier and serves as protection against pathogens and toxic substances.
There are numerous toxic particles in the outside air that affect the skin. It prevents pathogens from penetrating the inside of the body. The skin reacts quite quickly to toxic substances.
Forms
A skin rash can be differentiated according to its cause – i.e. whether it is toxic, allergic or due to illness. On the other hand, rashes are distinguished by their appearance and extent. Skin irritations can occur in a single spot or over a large area of the entire back.
The reddened areas can be sharply defined or merge into one another. Last but not least, the exanthema may be flat or stand out from the skin. One also describes the consistency of the skin, determines whether it is dry or moist and whether it scales or not.
Causes
Click here for the main article: Causes of a skin rashToxic causes of a skin rash on the back are mainly chemical substances that do not reach the skin in the form of lotions, gels and creams. These are mainly nickel and other metals, as well as chemical processing in textiles that come into close contact with the skin. It is often the case that the first contact does not yet lead to a skin rash on the back.
The toxic substances enter the upper skin area and cause the immune system to form antibodies. If there is renewed contact with the substance, the antibodies trigger an immune response and there is an increased influx of blood into the skin capillaries, which leads to the classic redness of the skin. The itching described above is caused by the release of histamine.
A skin irritation after an insect bite is also called a toxic rash. In this case, poison penetrates the skin, which can lead to an allergic reaction with redness, swelling and itching. Allergies can be triggered by any substance that hits the skin.
Often one does not know later what the actual triggering substance was. Sometimes, however, a connection can still be made. All shower gels, detergents, lotions or skin cosmetics can in principle trigger a skin rash.
Newly used preparations in particular can cause the skin on the back to redden and itch. However, sometimes a cosmetic product is used for a long time without any problems and then suddenly triggers an allergic reaction on the back. In addition to substances applied directly to the skin, substances that have entered the body through food or air can also trigger an allergy.
Very often after eating nuts or apples, skin irritation occurs in the area of the upper body and also the back. Sometimes pollen inhaled through the air (see: skin rash caused by pollen) can also contribute to an allergic reaction of the skin on the back. as well as detergent allergySun exposure can unfortunately also cause skin rashes.
In addition to the generally known sunburn (acute photodermatosis), which is characterized by severe redness as well as pain and itching, there are other dermatoses caused by sunlight. These include, for example, polymorphic light dermatosis, which is often mistakenly referred to as sun allergy. Itching skin symptoms usually occur after the first intensive contact with the sun in spring or summer.
These can be blisters, redness, weeping skin defects and the like. In addition to these relatively well-known clinical pictures, there are also somewhat less known skin rashes caused by sun exposure. These include phototoxic and photoallergic dermatoses.
Here, substances such as drugs, but also textiles or cosmetics, can be the cause of a sensitization of the skin to sunlight. Exposure to sunlight, or more precisely UV exposure, then causes unpleasant skin rashes. Numerous pathogens can also lead to skin rashes.The most common childhood illnesses to be mentioned here are the classic children’s diseases such as measles and scarlet fever, which after an appropriate initial phase can also lead to an itchy skin rash on the back.
If there is a sharp demarcation of a flat skin rash on the back, which is either very itchy but can also be painful and if clear blisters are visible, it can also be shingles. Patients suffering from shingles have experienced chickenpox in childhood or adolescence. The virus entered the body, caused the disease and then settled down, usually directly next to nerves.
If the immune system is weakened, e.g. by stress, shingles (herpes zoster) can be triggered again. In this case, sharp demarcation lines are formed in the area of the back or any other part of the body, as if drawn with a ruler. Rarely but nevertheless possible are skin irritations on the back due to fungal infestation.
Regions on the body, including the back, which frequently come into contact with sweat, are predestined for fungal infestation (also known as skin mycosis). Even if the skin in the armpits or in the groin is affected, a fungal disease must be considered. Children are particularly often affected by skin rashes.
These can be of very different nature. Besides infectious diseases, allergies also play a major role. The following section is intended to present the most important causes of a rash in children.
A special focus will be placed on rashes that preferably manifest themselves on the back. Measles: Measles is one of the generally known childhood diseases. They are caused by the measles virus.
Babies nowadays receive a measles vaccination as part of basic immunization. Should the disease develop, a red, maculopapular exanthema appears – the rash is large and partially confluent. It starts behind the ears and then spreads quickly to the entire body.
The rash is preceded by a prodromal stage with fever, rhinitis and a barking cough. The exanthema subsides after about 4 to 5 days, occasionally with scaling. Chickenpox: Chickenpox (also a typical childhood disease) is caused by the varicella zoster virus and is therefore also called varicella.
Typically, the exanthema begins with small red spots on the back, chest and abdomen and later spreads to the extremities. The spots typically itch and then develop into small nodules. These nodules later burst and become crusty.
The diagnosis is quite clear. The colorful picture of different skin appearances, blisters, spots and nodules is also called “starry sky”. Rubella:The rubella usually begins with a kind of light rhinitis and fever as well as headache and aching limbs.
The rash is light red and consists of medium-sized spots. These do not flow together and start behind the ears and on the head. The rash then quickly spreads to the trunk.
Ringel rubella:Ringel rubella also begins with a kind of mild, flu-like discomfort. The rash begins on the face, leaving the mouth and nose uncovered. It then spreads to the trunk.
It is an initially confluent maculopapular rash. In the course of time it shows a central paleness and presents itself as garland-shaped. After about 5 to 8 days the exanthema completely disappears.
In 50% of the cases itching also occurs. Three-day fever: The three-day fever (exanthema subitum) primarily affects children aged 6 months to 2 years. The name of the disease is also indicative of it.
A high fever lasting 3 days develops. When the temperature drops, a fine-spotted, maculopapular exanthema appears, which is mainly present on the back and abdomen. This rash is often visible for only a few hours to a maximum of 3 days.
Acne vulgaris: Acne vulgaris is a skin disease that affects almost 85% of the population at some point in time. It usually begins at the age of 11 to 12 years and heals by the age of 30 at the latest. Affected are mainly regions rich in sebum such as the face or the shoulders.
A V-shaped infestation of the chest and back is observed. The primary skin symptoms of acne can be divided into closed and open comedones. Closed comedones empty white contents when pressure is applied, whereas open comedones are characterized by a central black dot.Papules, pustules, knots or even scars can also occur.
Diaper dermatitis: Diaper dermatitis develops in the diaper area due to irritation of the skin, e.g. due to diarrhoea or prolonged contact with stool and urine. It leads to blurred, extensive redness, weeping areas and scaling. Diaper dermatitis can also appear on the lower back, abdomen and thighs.
Scarlet fever: Scarlet fever is a bacterial infection that usually affects children between 4 and 10 years of age. It begins abruptly with high fever, sore throat and difficulty swallowing and a reduced general condition. After about 2 days the exanthema stage begins, in which a skin rash develops.
This is found on the face and trunk. However, it is particularly pronounced in the groin and in other joint bends. The cheeks are reddened and a fine-spotted, maculopapular exanthema appears. After about one week the rash fades. In the second week of the disease a scaling may occur, which mainly affects the face, the trunk as well as the palms of the hands and the soles of the feet.
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