Symptoms of Scabies
Scabies infection almost always occurs with prolonged direct skin-skin contact. Sexual transmission predominates. Children often become infected when they sleep in the same bed with sick parents. In crowded groups, other direct skin contacts are also implemented (contact sports, fussing of children, frequent and strong handshakes, etc.). Although a number of guidelines continue to reproduce outdated information about the transfer of scabies through household items (household items, bedding, etc.), experts agree that such a route of infection is extremely unlikely. An exception is cases of Norwegian scabies, when up to several million ticks live on the patient’s body (in typical cases, it is 10-20 ticks).
A key experiment, which proved that direct contact with the patient’s skin plays the dominant role in scabies transmission, was performed in 1940 in the UK under the supervision of Mellanby. Of the 272 attempts to infect volunteers by putting them to bed, with which patients with severe scabies just got up, only 4 attempts led to the disease.
Such features of the transmission of parasitosis are explained by the following data on its biology:
- scabies mite is inactive during the day; females are selected to the surface only in the late evening and at night;
- the tick needs about 30 minutes to penetrate the host skin;
- in the external environment, the tick quickly dies (at 21C and a humidity of 40-80%, the parasite dies after 24-36 hours), the warmer and drier, the faster; the tick loses its activity even earlier.
Currently, more and more manuals and medical reviews include scabies along with phthyroidism in the list of sexually transmitted diseases, although for the transmission of these parasitoses it is not so much the coitus itself that matters, but how long the bodies touch in bed.
You should know that the mites that cause scabies in animals (dogs, cats, horses, etc.) can also get to humans, but they do not find suitable conditions for their existence here and die pretty quickly, causing only short-term itching and rash, which without re-infection pass even without treatment.
The incubation period of scabies is 7-10 days.
Itching is characterized by itching, especially worse at night, paired nodular-vesicular eruptions with localization in certain favorite places. Externally, the scabies are barely elevated as thin as a thread, strips running straight, or zigzag. Often the end of the course ends with a transparent bubble through which a white dot is visible – the body of the tick. Sometimes scabies can not be detected (scabies without moves).
Small bites, the size of a millet seed and slightly larger nodules, appear on the site of the bites, which are covered with bloody crusts due to scratching. The primary rash is represented by small erythematous papules, which can be scattered or multiple, confluent. Over time, papules can transform into a vesicular (vesicles), rarely a bullous (pemphigoid) rash. The severity of the rash does not correlate with the number of parasites, but is due to an allergic reaction to the products of their vital activity.
Permanent damage to the skin is often complicated by various types of pustular infection and the development of the eczema process.
Favorite localization of scabies rash: hands, especially interdigital folds and lateral surfaces of fingers, flexion folds of forearms and shoulders, nipple area, especially in women, buttocks, skin of the penis in men, hips, popliteal hollows, soles in the small children, and also face and even the scalp.
The presence of pruritus, primary rash and scabies is the main clinical symptom of a typical form of scabies.
In domestic dermatology, it is customary to distinguish characteristic eponymous symptoms that facilitate the diagnosis:
- Ardi’s symptom – pustules and purulent crusts on the elbows and in their circumference;
- Gorchakov’s symptom – there are bloody crusts in the same place;
- Michaelis symptom – bloody crusts and impetiginous rashes in the intergluteal fold with a transition to the sacrum;
- Cesari’s symptom – detection of scabies in the form of a slight elevation upon palpation.
Scratching often leads to severe bacterial infection of the primary elements with the development of pyoderma, which in rare cases can lead to post-streptococcal glomerulonephritis and possibly rheumatic heart damage. Sometimes pyoderma with scabies is accompanied by the appearance of boils, ecthyma and abscesses, accompanied by lymphadenitis and lymphangitis. A number of patients develop microbial eczema or allergic dermatitis, which, along with pyoderma, in domestic dermatology are classified as complicated forms of scabies. Complications of scabies in the form of dermatitis and pyoderma occur in approximately 50% of patients.
In children, especially infants, along with papulovesicles and scabies, there is a vesiculuricar rash, weeping develops, paronychia and onychia occur. In children in the first 6 months. The clinical picture of scabies often resembles hives and is characterized by a large number of blisters combed and covered in the center with a bloody crust, which are localized on the skin of the face, back, buttocks. Later, a small vesicular rash prevails, sometimes blisters (pemphigoid form). In some cases, scabies in children resembles acute eczema, accompanied by intense itching not only in places where ticks are localized, but also in remote areas of the skin. In this regard, sleep disturbance is often observed, more often complications are observed in the form of allergic dermatitis, pyoderma such as impetigo. Lymphadenitis and lymphangitis can occur, leukocytosis and lymphocytosis, eosinophilia, accelerated ESR, albuminuria are observed. Infants may develop sepsis. In recent years, there has been an increase in cases of atypical scabies with erased forms in children.
Approximately 7% of patients develop nodular (nodular) scabies, in which bluish-crimson or brownish rounded skin seals of 2-20 mm in diameter are formed, which can persist for several weeks even if there are no parasites in them. In fact, these seals are a special version of the itch course in the form of a lenticular papule. The reason for the occurrence of such elements is a special predisposition of the skin to respond to the action of the stimulus by reactive hyperplasia of the lymphoid tissue in the places of its greatest accumulation. It prevails on the scrotum, penis, buttocks, elbows, in the front-axillary region, sometimes nodules form in the perianal region. Nadular scabies is also called scabious lymphoplasia. Since there are no live ticks in the nodules, their formation is explained by a pronounced immune-allergic reaction of the host organism to the products of their vital activity. In cases of reinfestation, there is a relapse of scabious lymphoplasia in old places without the presence of a course. Nodules are accompanied by severe itching and, in some cases, corticosteroid injections are used to treat them.
Non-typical forms of scabies include Norwegian scabies, “clean” scabies (incognito scabies) and pseudosarcoptosis.
Norwegian (cortical, crustaceous) scabies was first described by Norwegian doctors Beck and Danielssen (C. W. Boeck, D. C. Danielssen) in 1848. Norwegian scabies develops more often in individuals with predisposing disorders of immunity or skin sensitivity (see Pathogenesis). however, in about 40% of cases, it is observed in people not belonging to risk groups, which suggests a possible genetic predisposition in such patients. Eosinophilia is observed in 58% of patients with Norwegian scabies, an increase in IgE level (17 times on average) is detected in 96% of cases. Clinically, Norwegian scabies looks like psoriasiform dermatitis with an acral distribution and the presence of variable whitish scales. The subungual zones are also usually involved with the development of severe hyperkeratosis, leading to a thickening and degeneration of the nail plate. In some cases, with Norwegian scabies, the scalp, face, neck and buttocks are mainly affected. About half of patients with Norwegian scabies do not feel itching at all. Due to the fact that with Norwegian scabies, more than a million live parasites can exist on the patient’s body (with typical forms, the number of ticks on average is 15 individuals), this form of the disease is extremely contagious.
Scabies of “clean” or “incognito” scabies are detected in people who often wash in everyday life or by the nature of their production activities. Moreover, the majority of the scabies tick population is mechanically removed from the patient’s body. The clinic of the disease corresponds to typical scabies with minimal manifestation. Complications often mask the true clinical picture of scabies. The most common are pyoderma and dermatitis, less common are microbial eczema and urticaria.
Pseudosarcoptosis is a disease that occurs in humans upon infection with scabies mites (S. scabiei other than var. Homonis) from other mammals (most often dogs). The disease is characterized by a short incubation period, the absence of scabies (ticks do not breed on an unusual host), urticaria papules in open areas of the skin. From person to person, the disease is not transmitted.
Spontaneous scabies never passes and can last for many months and years, sometimes worsening. To cure the patient with scabies, it is enough to destroy the tick and its eggs, which is easily achieved by the use of local funds; no general treatment is required here.
Preparations for the treatment of scabies can be divided into 4 groups:
- Synthetic derivatives of balsamic agents (benzyl benzoate);
- Sulfur or its derivatives: 10-33% sulfur ointments, Wilkinson ointment;
- Insecticidal antiparasitic agents – K soap, 510% pyrethra ointment (Dolma chamomile), liquids such as flicide, lysole, creolin;
- “Folk” methods and means – gasoline, kerosene, autol oil, fuel oil, crude oil, ash liquor.
Before using the funds, the patient should wash himself to mechanically remove ticks and microbial flora from the surface of the skin, and rub these preparations into the entire skin (except for the head), especially vigorously in places of typical localization. In some cases (complicated by pyoderma and eczematous dermatitis, rubbing is replaced by lubrication of the affected areas with the indicated antiparasitic drugs.
The most commonly used emulsion is benzyl benzoate: 20% for adults and 10% for young children. Treatment is carried out according to the following scheme: on the first day, the emulsion with a cotton swab is successively rubbed into all lesions twice for 10 minutes with a 10-minute break. After this, the patient puts on disinfected clothes and changes bedding. On the second day, rubbing is repeated. 3 days after that – washing in the shower and changing clothes again.
The method of Demyanovich. Two solutions are made: No. 1 – 60% sodium hyposulfate and No. 2 – 6% hydrochloric acid solution. Treatment is carried out in a warm room. Solution No. 1 is poured into the dishes in an amount of 100 ml. The patient strips naked, the solution is rubbed into the skin with the hand in the following sequence: in the left shoulder and left arm; in the right shoulder in the right hand; in the body; in the left leg; in the right leg. Rubbed for 2 minutes with vigorous movements and especially carefully in those places where there are scabies rashes. Then for several minutes the patient rests. During this time, the solution dries quickly enough, the skin, covered with the smallest crystals of sodium hyposulfate, becomes white, as if powdered. After that, the second solution is rubbed with the same solution and in the same sequence, also for 2 minutes in each area. Crystals of salt, destroying the tires of the itch passages facilitate the flow of the drug directly into the passages.
After drying, they begin to treat the skin with hydrochloric acid. This solution should be taken directly from the bottle, pouring it, as needed in the palm of your hand. Rubbing is carried out in the same sequence, but it lasts only one minute. After drying, the skin is repeated 2 more times.
Then the patient puts on clean linen and does not wash off the remaining medicines for 3 days, and then washes. As a result of the interaction of a solution of sodium hyposulfate and hydrochloric acid, sulfur dioxide and sulfur are released, which kill the scabies mite, their eggs and larvae. In children with scabies, treatment according to the method of prof. Demyanovich usually spend parents. If the first course did not give a full recovery, then after 2-5 days, treatment should be repeated. In extremely rare cases, a 2nd course is required.
Sulfur ointment (33%) is rubbed into the whole body, except the head, 1 time at night for 4-5 days. Then 1-2 days of rubbing is not done, the patient all this time remains in the same linen, which is soaked in ointment. Then he washes and puts on everything clean. People with hypersensitivity often develop dermatitis, so rubbing sulfuric ointment in areas with thin and delicate skin should be done with extreme caution, and in children, apply ointments of 10-20% concentration. A one-time rubbing of sulfuric ointment is also proposed. In this case, the patient first moisturizes the body with soapy water and rubs sulfuric ointment into the affected areas for 2 hours, after which the skin is dusted with talcum powder or starch. The ointment is not washed off for 3 days, then the patient is washed and changes clothes.
Good therapeutic results can be obtained from the use of an old folk remedy – a simple wood ash, which contains enough sulfur compounds to destroy the scabies mite. Either an ointment (30 parts of ash and 70 parts of any fat) is prepared from ash, which is used similarly to sulfuric ointment, or a glass of ash and two glasses of water are taken and boiled for 20 minutes. After boiling, the liquid is filtered through a gauze or cloth bag. The residue remaining in the bag is moistened in the resulting liquid liquor and rubbed for 1/2 hour into the skin every day for a week.
Kerosene in half with any vegetable oil, for 2-3 days, once at night, lubricate the whole body and spray linen, stockings, mittens; in the morning they wash the body and change clothes; usually to cure it is enough to lubricate 2-3 times. The disadvantage of this method is the possibility of dermatitis, especially in children.
Immediately after the end of treatment, all patient’s underwear, both wearable and bedding, must be thoroughly “washed and boiled; outer clothing should be decontaminated from a tick in a disinfection chamber or by ironing with a hot iron, especially from the inside, or ventilating in air for 5 -7 days. They also come with a mattress, a blanket, and other things of the patient. The simultaneous treatment of all patients is extremely important – in the same family, school, hostel, etc.
Modern methods of treating scabies in children and adults include the use of drugs such as lindane, crotamiton, permethrin and spregal, available in solution, cream or as an aerosol.
Crotamiton. Before prescribing the drug to the patient, it is desirable to determine the sensitivity to it of the microflora that caused the disease in this patient. The drug is used externally. For scabies, a cream or lotion (after shaking) is used as follows. After a bath or shower, a cream or lotion is carefully rubbed into the skin from the chin to the toes, paying particular attention to folds and folds. The procedure is repeated after 24 hours. The next day, change clothes and bedding. 48 hours after the second rubbing, a hygiene bath is taken. When used as an antipruritic, crotamiton is gently rubbed into the skin until completely absorbed. If necessary, rubbing the drug is repeated.
Spregal. Before prescribing the drug to the patient, it is desirable to determine the sensitivity to it of the microflora that caused the disease in this patient. Treatment begins in the evening at 18-19 hours, so that the drug acts during the night. Do not wash after applying the drug. First, they treat the infected, then all the other members of the family. Spray the entire surface of the body, except for the head and face, from a distance of 20-30 cm from the surface of the skin. The drug is first applied to the body, and then to the limbs, without leaving any area of the body untreated (the treated areas begin to shine). Particularly carefully, the drug is applied between the fingers, toes, in the armpits, perineum, on all bends and affected areas and left on the skin for 12 hours. After 12 hours, it is necessary to thoroughly wash with soap and wipe. As a rule, a single use of spregal is enough. However, it must be borne in mind that even in the case of the effectiveness of the treatment, itching and other symptoms can occur for another 8-10 days. If after this period the symptoms persist, you can apply the drug again. In case of infected scabies, it is first necessary to cure impetigo (superficial pustular skin lesions with the formation of purulent crusts).
If scabies is accompanied by eczema, 24 hours before the use of spregal, lubricate the affected surface with glucocorticoid ointment (containing hormones of the adrenal cortex or their synthetic analogues, for example, fluorocort). When treating children and newborns during the spraying of the drug, it is necessary to close their nose and mouth with a tissue; in case of changing diapers, it is necessary to re-treat the entire area of the buttocks. When localizing the scratches on the face, they are treated with cotton wool moistened with a spraygel. To avoid secondary infection, it is necessary to process the bed and clothes. One spray can of spregal is enough to treat three people. Avoid getting the drug on the face. In case of accidental contact with eyes, rinse thoroughly with warm water.
In the case of a preserved immune status, the disease does not pose an immediate threat to life. Timely adequate treatment can completely eliminate the symptoms and consequences of the disease. Disability is fully restored.
In rare cases, observed mainly in the poorest countries, complicated scabies can lead to post-streptococcal glomerulonephritis and possibly rheumatic heart disease.