Korosta is a contagious disease of the dermatological profile that occurs as a result of skin lesions by a specific parasite, namely, a scabie mite. The primary way of infection is "contact", through the skin from a person who is the carrier of the scab, and this pathology is characterized by a high indicator of contagiousness. When primary contact with a patient is infected with a corpuscle, in a healthy person the initial signs of a cow appear after a week in the form of development of various elements of the rash diffusely or localized.
Experts in the field of skin diseases note a certain seasonality of the scab, i.e. a sharp increase in the indicator of contagiosity in the autumn-winter period. This correlation dependence is due to the biological needs of the causative agent of the crust. So, in conditions of low temperature indexes and high humidity, there is a significant activation of the tick. In the summer period, the cow is observed much less often, because in the warm period there is increased sweating in humans, and sweat contains substances that have antimicrobial activity.
Causes of bumps
The only causative agent of the scab, as a common dermatological pathology, is the "itch itch" parasite, the discovery of which occurs at the end of the seventeenth century. Korosta belongs to the category of anthroponotic parasitic infections, since possible infection of a person occurs through skin contact from a patient with scab or household things containing ticks. In this situation, there is an indirect type of infection of the pathogen by the pathogen. The most favorable habitat of the itch mite is a medium with increased humidity parameters, since under these conditions the parasite can be in the active state for more than five days.
The lowest rate of morbidity is observed in highly developed countries. The risk group for this dermatological pathology is children of preschool and school age, due to insufficient development of immune responses, as well as direct contact with each other in the conditions of an organized collective.
Before considering the pathogenesis of development of the scab, special attention should be paid to the study of the structure and functional activity of the main pathogen of the scab - itchy pruritus. This parasite is characterized by sexual dimorphism, and in the development of the scab, the activity of the female scabies mite is more important, which, after only 12 hours after fertilization, is capable of depositing up to four eggs on the skin of a human. In connection with the fact that the saliva of the tick contains a high concentration of proteolytic enzymes capable of destroying keratin, the process of laying eggs is accompanied by the formation of "intracutaneous itch tendons", the detection of which is considered the main pathognomonic symptom of this disease. After the initial deposition of eggs, the female continues to parasitize the skin, and within two weeks new tick specimens form from its eggs, thus the chasm is characterized by rapid progression and continuous flow.
The infection of a healthy person with scab can occur at almost any stage of the disease, and the formation of clinical manifestations is largely due to the concomitant immune and allergic reaction of the body to the introduction of the parasite. After direct infection of a person, a long latent period occurs, which can reach a month, and at this time a massive multiplication of the pathogen occurs in the skin. The debut of the disease in the form of development of pronounced pruritus is observed only after the development of an adequate allergic reaction of the organism in response to the release of the products of the mite's vital activity directly into the thickness of the skin. In patients with immunodeficient conditions, clinical manifestations of the scab in the form of pruritus are practically not observed due to the impossibility of forming a normal immune and allergic response to parasitic damage to the body.
Due to the fact that the formation of intradermal passages is accompanied by severe itching and scratching of the skin, favorable conditions are created for activating the obligate microflora with the development of purulent complications in the form of pyoderma . Unfortunately, the recovery of patients suffering from scabies is not accompanied by the formation of persistent immunity, so the risk of re-infection of this category of people remains high throughout life.
Symptoms of scabies
The main clinical criterion of the crust is a pronounced intradermal itching, prone to intensifying in the evening and night. However, the debut of the disease, as a rule, is observed in the formation of typical elements of the rash on the body. Not in all situations, the scab is accompanied by the formation of specific eruptions in the form of papules and vesicles, so a person infected with scab can not for a long time associate its condition with this pathology, and seek medical help from an allergist. However, the appearance of concomitant intradermal itching leaves no doubt about the correctness of the diagnosis of "scab".
The duration of the incubation or asymptomatic period in each case is different and can vary from one day to two weeks. In this time period, a person can not notice absolutely no changes in the state of their own health, but in this period he already is a carrier of the scab and is a danger to people who are in close contact with him.
Korosta has a significant polymorphism of the elements of the rash, so in some situations, early diagnosis of this disease is difficult, but the detection pathognomonic "korolevyh / scabious intradermal strokes" in the form of meandering lines on the skin, differing in color from surrounding tissues, can confidently establish a correct diagnosis, even before additional survey methods. With a more detailed examination of the parasitic intradermal stroke, in most cases it is possible to visualize the vesicle in which the tick body is located as a black dot. Another specific symptom of the scab is the priority localization of the elements of the rash in the projection of the natural folds of the skin, the lateral surfaces of the upper and lower extremities, and also the trunk.
Most often, the scab is manifested by the formation of papules (a rash that rises above the surface of the skin) and vesicles (papules containing a liquid component), but with a prolonged course of the disease, the secondary elements of the rash appear in the foreground in the form of excoriations and hyperkeratosis . In children, the scalp of the scalp and the upper half of the trunk is more often developed, and for adults the chest is more characteristic.
The crust on the body is characterized by rapid spread and polymorphism of the rash, and for the adult category of patients the skin lesions of the mammary glands, the scrotum and even the penis are characteristic. Primary localization of skin changes in the form of papules and vesicles are the hands, and when combing the skin, the pathogen spreads further, which concentrates in the elements of the rash. In this regard, the primary treatment measure for the scab is adequate disinfecting treatment of not only affected areas of the skin, but also the entire body, as well as underwear and clothing.
It should be borne in mind that in some patients the scab can occur in an atypical clinical variant, when even an experienced specialist can not detect parasitic strokes. This form of the crust is observed in a situation where the infection of a person occurred not by the method of direct contact of the female agent on the skin, but by its larvae. In addition, an atypical version of the crust is observed among persons who carefully observe the rules of personal hygiene, since during frequent bathing, part of the pathogens are mechanically removed from the surface of the skin.
Very rarely there can be a variant of pseudo-rash, in which infection by a tick occurs from a sick animal and the clinical symptom complex in this situation will be represented only by severe itching. This pathology does not need a specific drug intervention, and the clinical manifestations independently level after the removal of contact with the sick animal.
The complicated crust is distinguished by the addition of a purulent infection, which is why the patient has an increase in the intoxication syndrome, as well as the development of pyoderma.
A atypical version of the flow of the scab is scabious lymphoplasia, in which the elements of the rash are pink colored knots, reaching two centimeters in diameter and accompanied by intense itching. A pathognomonic symptom that distinguishes this form from the other pathologies of the dermatological profile is the detection of intradermal strokes. The development of these nodules is due to the immune response of the body in response to the introduction of the parasite and in most cases there is a small amount on the surface of the skin. These seals are nothing more than intradermal proliferation of elements of lymphoid tissue containing a large number of lymphocytic cells. This form of the crust is characterized by a prolonged course of clinical symptoms, even if all the recommendations of the doctor regarding the drug treatment are observed.
The worst form of influence on the patient's health condition, as well as unfavorable for recovery, is the Norwegian form of the scab, which is observed in persons suffering from severe immunity depression. The peculiarity of this clinical form of the crust is the diffuse spread of the elements of the rash, including the head region, as well as the concomitant hyperkeratosis, under the layer of which there is extensive wet eczema . The Norwegian cow is characterized by an extremely high degree of contagiosity.
Scab on the head
Recently, dermatologists have noted an increase in the number of patients who suffer from scabies with localization on the scalp or face. In some situations, in the event of the appearance of signs, the crusts are associated with scabies, but this is not entirely appropriate, since the scab in the nose or other part of the face may appear under the influence of various etiopathogenetic factors. The most common disease, in which the formation of a crust on the face, is seborrhea , resulting from a violation of the hormonal status of a person. In this regard, the scab in the ear, for example, is the lot of not only an otolaryngologist and dermatologist, but an endocrinologist.
In a situation where the appearance of a scab on the head is caused by a violation of saloobrazovaniya, or seborrhea, the initial treatment measure is the elimination of hormonal disorders, as well as the correction of eating behavior. If these conditions are met, in most cases the signs of the scorch are leveled off without using specific medications.
In addition to seborrhea, a background disease for the development of acne on the face is acne , which has nothing to do with adolescent acne. An acne vulgaris affects the persons of mature age and the primary cause of its occurrence is a violation of metabolic processes in the body. Most female patients try to hide the manifestations of the crust by applying decorative cosmetics, but only eliminating the root causes of the scab can have a beneficial effect.
The development of scabs in the nose is promoted by an allergic reaction in the form of pollinosis , in which there is an increase in the volume of the mucous membranes of the nasal passages and increased secretion of mucus. The mechanism of formation of the scab in the nasal passages is the excess production of mucus with its subsequent hardening. In the development of scab in the nasal passages, the curvature of the nasal septum is also of no small importance, in which there is a violation of air conduction.
Korost in children
In the children's category of patients, the scab proceeds with the development of similar clinical manifestations, as in adults, with the only difference being that the children are characterized by the development of polymorphic elements of the rash and the propensity to attach secondary infection, which significantly aggravates the course of the underlying disease.
Korosta in infants is manifested skin symptoms simulating hives, so in most cases timely diagnosis of this pathology is difficult. The favorite localization of the skin elements of the rash in case of a short in infants is the skin of the gluteal folds, the lateral surfaces of the trunk and face. In the debut of the disease, the cow is represented by papular and petechial rash, and with prolonged course there is a development of eczematous skin lesions of a widespread nature. These skin changes are accompanied not only by pruritus, but also by intense pain syndrome, which causes anxiety of the child, especially in the evening and at night.
In connection with the rapid progression of the disease, as well as the attachment of a secondary bacterial infection, a child suffering from a scab may have signs of lymphadenitis in the form of a significant increase in the group of regional lymphatic collectors, their soreness and hyperemia of the skin over the site of their localization. Given the complete absence of treatment measures aimed at eliminating the causative agent of the scab, the child may develop signs of severe generalized sepsis, which is life threatening for the patient. Medical products used to treat scabies in children can provoke the development of an allergic reaction in the form of dermatitis, so when the first signs of this condition appear, parents should immediately contact a treating dermatologist in order to correct further therapy.
In a situation where the clinical picture of a child's scabs is worn out or has atypical manifestations, an additional examination is shown, consisting in the bacteriological examination of the pathogen extracted from the "intradermal passage." This technique has a high degree of reliability and verification of the diagnosis in this situation is not difficult.
Treatment of scabies
Consolation is the fact that the scab does not belong to the category of recurrent skin diseases, but it is impossible to exclude the fact of repeated infection, since even after complete recovery the patient does not develop a permanent lifelong immunity. Re-infection is possible with skin contact with infected people, non-compliance with the recommendations of the attending physician regarding the taking of medicines, as well as non-observance of the rules for disinfecting the processing of personal hygiene items and clothing.
The main requirements for the use of topical medicines for the scab is that they stay on the skin for at least twelve hours a day, as well as applying the drug to the subungual bed, since the highest concentration of pathogen is found in this place of the human body. According to all normative documents of the sanitary service, all persons who are in close contact with the diseased scab are required to undergo a full course of preventive therapy, and, of course, the patient must comply with quarantine.
For the treatment of scabs, medicinal products with acaricidal action, in the form of ointments, extracts and infusions for external use are used to a greater extent. The majority of modern acaricidal agents are represented by combined preparations containing antipruritic and antiallergic components. Preparations for external use must be carefully rubbed directly into the areas of affected skin, and only the scab on the face has fundamental differences in treatment.
In addition to the means for topical external application, symptomatic drugs (Cetrin 1 tablet per day) should be used to alleviate the condition of the patient, which should be used in the evening. The most effective remedy for external use in case of a bust is Sulfur Ointment, however, this preparation is characterized by a high degree of allergization, which limits the scope of its use. A good acaricidal action has an emulsion of benzyl benzoate, capable of completely eliminating the pathogen within two days.
To eliminate the signs of scabies, 10% emulsion of benzyl benzoate is used in children, and for the adult category of patients, a 20% concentration of the drug should be used. It should be borne in mind that this drug can cause a pronounced allergic reaction, so it is recommended to apply it together with an antiallergic treatment regimen.
To treat the scabs on the front of the head, use Spregal, which does not cause an allergic reaction, and sparing the structure of the skin. This drug is also indicated for use in children of the age group and women during pregnancy or lactation, due to its low toxicity.
In most situations, patients do not seek qualified help for a long time, referring to constraint, however, thereby aggravating the course of the disease and provoking the development of severe complications.
? Korosta - which doctor should I contact ? If there is or suspected development, scabs should immediately seek advice from such doctors as a dermatologist and / or parasitologist.