Rash and itchy skin

When pruritogenic exanthema of various types, sizes and localization appears on the skin - that is, rashes and itching on the body, it can be symptoms not only of dermatological or infectious diseases, but also of some internal pathological changes in the body, to which the skin of the body reacted.

Causes of the rash and itchy skin

First of all, we consider dermatologic causes of the primary elements of skin lesions - skin diseases accompanied by itching and rashes (some of them will be discussed in more detail below).

As a result of constant exposure to skin irritating chemical compounds that people deal with in the home or workplace, the development of eczema is initiated. [1]

The simplest case, defined by dermatologists as simple contact dermatitis, is irritation and itching after shaving. [2]

Exposure to ultraviolet rays causes a rash to appear on the exposed skin of some people, indicative of photodermatitis on the face, legs and arms. [3]

There is also a good chance that the above symptoms are allergic itching and rashes caused by the body's immune response to a variety of substances and foods. Read more - Allergic skin rashes. [4], [5]

Infection with the scabies itch Sarcoptes scabiei and the development of acarodermatitis, called scabies, causes a rash and severe itching. [6] Swimming in natural bodies of water that do not have running water can infect the larvae of the parasitic worm Trichobilharzia, causing symptoms of schistosomiasis (cercariasis), such as itching and rashes on the shins, ankles and feet. [7] In this case, its first signs are visible on the skin in as little as a quarter of an hour.

And urticaria-like fine flaky rashes and itching on the chest and abdomen, on the back, palms of the hands and soles of the feet can be a sign of yersiniosis, which develops when the enterobacterium Yersinia enterocolitica enters the body. [8], [9]

In addition, a small red rash on the body and itching or allergic urticaria - often with transformation into erythema multiforme - appear as side effects of medication. You may encounter this problem when treating infections with antibiotics, during anti-tumor chemotherapy, when using cough, gastritis or parasitic infestations, for example, after taking Nemozole - an antihelminthic drug (the instructions indicate the possibility of this side effect). In these cases, we are talking about drug toxiderma. It can also include serum sickness, which can develop after prophylactic vaccination. [10], [11], [12]

Itchy focal rashes - follicular, papular, pustular - can also occur during pregnancy, and 75% of pregnant women experience such problems in the second or early third trimester. Dermatologists define such conditions as gestational urticaria or polymorphic (papular-urticarial) dermatosis of pregnancy. [13], [14], [15]

Rubella is particularly dangerous during pregnancy (during the first three months). [16] You can learn more about the causes of itching and rashes in pregnant women in the publications:

• Pregnancy rash
• Itching during pregnancy

Rash and itching in a baby

In pediatrics, much attention is paid to rashes and itching in the child: in the first months of life it is usually diaper dermatitis or sweating in a newborn, [17], [18] as well as a standard situation at the introduction of complementary foods - the appearance of exudative diathesis in an infant (which may be called infantile scabies). [19] Quite often papular rashes with intense itching in preschool age are diagnosed during examination as allergic rash in a child.

When the body is hypersensitized, children may be atopic dermatitis - an itchy, chronic inflammatory skin disease of unknown origin that usually begins in early childhood but also affects a significant number of adults and is associated with elevated IgE immunoglobulin levels. [20]

Keep in mind that red rash, itching, and fever are signs of childhood infections with skin rashes, including rubella (caused by Rubivirus), [21] chickenpox (caused by infection with the third type of herpes virus, HHV-3), [22] measles (associated with infection with Measles morbillivirus), [23] scarlatina (caused by Streptococcus pyogenes strains of hemolytic streptococcus) [24] and infantile roseola (pseudorabies or sudden exanthema), which is caused by the sixth type of herpes virus (HHV-6). [25] Also read - Different types of rashes in children

Risk factors

Doctors pay attention to risk factors for the appearance of itchy rashes in somatic diseases. These include liver and gallbladder diseases with cholestasis (bile stasis), which causes macules and papules (spots and nodules) of yellow-brownish or pinkish-orange color - xanthomas - on the hands, joints of the lower extremities, face, chest and neck. [26]

A similar kind of rash and itchiness is present with diabetes, and they usually appear on the buttocks, knees, shins, elbows, and forearms. [27], [28] It is also possible to get allergic urticaria to insulin injections. [29], [30]

A slightly itchy red rash in the form of plaques on the elbows and knees (with gradual lichenization - thickening) may be the result of zinc deficiency in the body, which leads to the development of enteropathic acrodermatitis. [31]

On the body may appear a fine rash and itching with low stomach acidity and anacid gastritis, with parasitic intestinal infestations and chronic constipation.

A patchy nodular rash with itching (most commonly on the shins) occurs in patients with an autoimmune inflammatory disease such as sarcoidosis. [32], [33]

In almost one in four patients with intolerance to grain protein (celiac disease), gastrointestinal problems are joined by dermatologic problems - in the form of Dühring's dermatitis herpetiformis, [34], which is apparently due to increased production of IgA antibodies to gluten.

Pathogenesis

Immune response to exo- and endogenous factors on the part of dendritic cells of the basal layer of the skin and epidermal keratinocytes producing inflammatory mediators - cytokines and chemokines, and the subsequent reciprocal activation of macrophages, T- and B-lymphocytes, mononuclear leukocytes, neutrophilic and eosinophilic granulocytes determine the pathogenesis of exanthema.

And the mechanism of itching is the entry into the blood of the mediator of allergic reactions histamine from the mastocytes (mast cells) of the skin. More details in the material - Pathogenesis of itchy skin.

Also see the publication - Atopic and allergic conditions, which highlights the pathogenesis of skin reactions manifested by pruritic rashes.

Recent studies have linked cases with idiopathic skin reactions, such as those seen in atopic dermatitis, to abnormalities in certain genes that are involved in maintaining the epidermal barrier.

Localization and characterization of the rash accompanied by itching

To determine the etiology of skin rashes is important for their morphological characteristics and the place of appearance - localization, more in the articles:

• Skin rash (skin rash)
• Red spots in various diseases and conditions
• Types of red spots on the skin of the body

The complete clinical picture is given by the patients' general condition and accompanying or preceding symptoms, particularly fever.

Rash, itching and fever are observed in pediatric infectious diseases, in cases of sudden exanthema, in pink pityriasis (Gibert's rash), [35] meningococcal infection, [36] infectious erythema, [37], [38] septicemia, [39] enteroviral vesicular stomatitis with exanthema or hand-foot-mouth syndrome. [40], [41]

Experts consider the most likely causes of a rash without itching and fever to be: sweats, [42] rosacea, [43] miliums (small white pimples on the skin of the face and other parts of the body), [44] follicular keratosis (a small rash near hair follicles on the forearms, thighs, and buttocks), [45] contact dermatitis, dermatofibroma (manifested by small reddish-brown papules on the lower legs).

In acute skin reactions of allergic etiology, atopic dermatitis, [46] scarlatina, pityriasis and strepto- and staphylococcal skin lesions (impetigo) rashes with itching and flaking are observed. [47], [48] Also flaking spots in psoriasis. [49]

Itching and rashes on the head can be signs of seborrheic dermatitis, [50] demodecosis of the head, [51] pityriasis, [52] psoriasis.

A fine facial rash and itching are seen in rubella and other childhood infections, shingles, allergies, chronic diffuse neurodermatitis. [53] The cheeks, forehead and nose area are affected by skin changes in lupus erythematosus. [54], [55]

And the vesicular rash and itching on the lips is most often the result of Herpes simplex virus lesions - herpes simplex virus (herpes infection). [56]

A flaky papular follicular rash and itching on the neck as well as on the chest, abdomen, arms and legs is characteristic of the so-called shingles. This localization is observed in Vidal's lichen (limited neurodermatitis), which, in addition to the skin on the back and sides of the neck, appears under the knees and in the bends of the elbows, on the thighs and buttocks.

Itching and rashes on hands and feet

Once again about the causes of the mentioned symptoms of this localization can be read in the article - Spots on the hands and feet in a child and adults

Rashes and itching on the hands occur in most dermatologic diseases. Thus, on the palms, rash and itching is provoked by eczema of the palms, [57] occurring as contact dermatitis; dyshidrotic eczema (with blisters on the background of increased dryness of the skin); [58] fungal infection with the development of ringworm (in the form of ring-shaped rashes caused by the fungus Trichophyton rubrum). [59] In addition, rashes on the upper extremities are seen in primary biliary cirrhosis (autoimmune liver disease). [60]

See also - Red spots on the palms of the hands

Simultaneously with the palms, there is a rash and itching of the feet (plantar and lateral parts) in Andrews' pustular bacteremia, [61] associated with streptococcal infection, or, according to another version, in scarlatinaiform desquamative erythema (accompanied by fever). [62]

Rashes and itching on the hands are signs of eczema and contact dermatitis, red squamous lichen planus (with purple papules) [63] and lichenoid papular myxedema (also affecting the forearms and neck area). [64]

Patients with atopic dermatitis, psoriasis, enteropathic acrodermatitis [65] or dermatomyositis have rash and itching on the elbows. [66]

Sweating, allergies to deodorizing products, irritant dermatitis after shaving and waxing, scabies and shingles [67] cause rashes and itching under the armpits.

Itching and rashes on the feet - most often in the form of red patches on the feet of adults and children - are rarely limited to localized rashes. This means that, for example, rashes and itching of the feet in nodular erythema, which occurs in some infectious diseases, are combined with rashes on the lower legs, thighs and arms. [68]

Among the diagnoses that take into account such a symptom as itching and rash on the shins and ankles, experts call: atopic and contact dermatitis, venous (gravitational) dermatitis, discoid and varicose eczema, simple lichen planus, nodular prurigo (scabies), [69] dermatofibroma. [70]

Rashes and itchy knees are associated with just as many conditions, including scabies, psoriasis, and dermatitis - irritant contact, allergic, atopic, herpetiform, and enteropathic acrodermatitis.

Rashes and itching on the thighs are mostly caused by the same causes, but also by vasculitis (inflammation of blood vessels with red and purple itchy patches on the skin and joint pain). On the inner thighs, red squamous lichen planus and bullous pemphigoid, which is common in the elderly.

Rash and itching on the chest, abdomen, sides, back and armpits

Against a background of severe fever, headache and joint pain, a rash and itching on the chest appear in pink pityriasis [71] and Kaposi's herpetic eczema. [72]

And on the lateral surfaces of the chest (as well as on the lower abdomen, on the shoulder blades, on the thighs and knee bends) localizes papular rash in psoriasiform nodular dermatitis (drop-shaped parapsoriasis). [73]

A nodular or plaque-like rash and itching on the flanks and abdomen occurs in red flat lice, scabies, psoriasis, allergic dermatitis. Rashes appear in the same area due to limited neurodermatitis.

A red rash and itching on the back can indicate not only scabies, red shingles, dermatomycosis or folliculitis (caused by Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pyogenes). But also Dühring's dermatitis herpetiformis.

Itching and rashes on the buttocks (in the form of papules) can be a symptom of scabies, chicken pox or neurodermatosis, which also affects the skin on the lower back, back, abdomen and in the folds of the limbs. When nodular, patchy rashes appear on the skin of the buttocks and hips - after several days of fever, headache, joint and muscle pain - physicians should suspect that the patient has infectious Rosenberg's erythema.

Itching and rashes in the intimate area

In the groin, rash and itching can be genital infection caused by herpes simplex virus; scabies, contact, atopic and allergic dermatitis; psoriasis and psoriasis and lichen planus and ringworm. [74]

A papular vesicular rash and itching on the pubic area and groin are signs of phthyriasis following bites from the pubic louse (Phthirus pubis). In women, however, chronic obstruction of the ducts of the apocrine sweat glands with Fox-Fordyce disease affecting the axillae should not be ruled out. [75]

Also itching and rash in the intimate area in the form of white small papules or plaques most often indicate sclerotic lichen (drop scleroderma). [76] By the way, in men, a similar rash on the head of the penis and itching also happens, and some experts call it obliterating xerotic balanitis. [77] In addition, red pustular rash of the above location appears due to genital herpes, macular rash - in reverse psoriasis, and papular rash - in shiny lichen planus and sarcoidosis. The development of condom allergy. Cannot be ruled out.

Complications and consequences

It is common to associate the main consequences and complications of itchy skin rashes with excoriation (scratching), as the damaged skin is easily infected and inflamed - with possible purulent necrosis.

Although you should also consider the causes of rash and itching, which can also have their own complications, for example, the development of otitis media and sore throat in rubella, meningoencephalitis - in measles, etc.

Dermatoses in pregnancy, such as atopic, causes only intense skin itching and rashes, but in some cases there is a risk of anomalies, prematurity and intrauterine fetal death (statistically, in almost 10% of cases).

If complications of scleroatrophic lichen (on the head of the penis) are noted, then the narrowing of the foreskin and the development of phimosis are not excluded.

Diagnostics of the rash and itchy skin

It is not difficult to diagnose rashes in children's infections: the pediatrician is enough to conduct an examination, collect anamnesis and record complaints.

Instrumental diagnosis may be limited to dermatoscopy, and a Wood's lamp is used to detect mycoses.

For more information see. - Skin Research.

In all other cases, a more thorough examination is performed. If the diagnosis is not clear after anamnesis and physical examination, it may be necessary to consult doctors of other specialties, in particular for diagnosis of allergy, to assess the condition of the liver, lymph nodes etc. If necessary, hardware examinations (ultrasound, X-ray, CT scan) are prescribed. [78]

The following tests are taken: blood (detailed biochemical), urine (total), coprogram (for helminthiasis). The level of blood antibodies is also determined, and a scraping of rashes and/or skin biopsy is done. [79]

The most important component is differential diagnosis. More information in the material - Diagnosis of skin itching

Treatment of the rash and itchy skin

Coverage of therapy for pruritus and rashes of specific etiologies is beyond the scope of this article. Treatment of skin rashes and pruritus is usually with external agents and varies according to their cause.

Patients are usually concerned with one question: how to get rid of irritation and itching?

Read in detail:

• How to get rid of irritation after shaving
• Treatment of itchy skin
• Allergic rash treatment

Anti-allergy medications for itching and irritation to take orally are antihistamines (Cetirizine, Zyrtec, Loratadine, Claritin, Fexofenadine, etc.), that is - Pills that relieve itchy skin

Ointments, creams and gels for itching and irritation are listed (with detailed descriptions) in special articles:

• Itching ointment
• Creams for itching
• Ointments for skin rashes
• Scabies ointment

It should be borne in mind that Cinovit cream is a cosmeceutical agent with zinc pyrithione, and dermatologists recommend using ordinary zinc ointment or salicylic-zinc paste. And cream or gel Panthenol (D-Panthenol, Dexpanthenol, Pantoderm, Bepanten) with provitamin B5) does not treat dermatological diseases, but only promotes regeneration of damaged skin (used for sweating and irritations).

The etiologic treatment of skin rash and itching of autoimmune origin is currently limited to topical application of Pimecrolimus cream (Elidel) and ointments Protopik and Tacropik (with similarly active tacrolimus), which inhibit the activity of cellular immunity by inhibiting the synthesis of inflammatory mediators.

Positive effect gives physiotherapy treatment (using phototherapy, phonophoresis, etc.), all the details in the material - Physiotherapy for dermatitis and dermatosis.

It is possible folk treatment (oatmeal baths and compresses) and herbal treatment (calendula, sage, chamomile, comfrey, plantain, celandine), more details:

• Treatment of diathesis with folk remedies
• Medicinal herbs for allergies

Prevention

Prevention of these symptoms is prevention of the diseases in which they appear. This is only possible by vaccination against measles and chickenpox.

If you are prone to skin reactions, it is recommended:

• Allergy diet
• Diet in atopic dermatitis

It is also advised to protect the skin with emollients, which are emollients and moisturizers that form a thin film that prevents moisture loss. They are often used for dry and flaky skin, as well as for eczema and dermatitis.

Forecast

Childhood infections t simple skin irritations go away, but immune-mediated dermatitis belongs to chronic pathologies, so that the prognosis also depends entirely on the etiology.