scabies

from Wikipedia, the free encyclopedia
Classification according to ICD-10
B86 Scabies
scabies
infestation by itch mites
infestation by Sarcoptes scabiei
infestation Scabies
Borken scabies
eczema scabiosum
ICD-10 online (WHO version 2019)

Scabies , technically also scabies , scabies (from Latin scabere , 'to scratch') or acarodermatitis , formerly also known as “ mange ” in humans , is a widespread parasitic skin disease in humans caused by the grave mite or scabies mite (especially Sarcoptes scabiei ) . The hemispherical, 0.3-0.5 millimeters females of the itch mite burrow into the skin ( epidermis ) and place there from in the channels (canaliculi, Burrows) droppings (scybala) and their eggs. Their secretions lead to considerable damage to the skin. The incubation period is about a few days to six weeks. According to Section 34 of the Infection Protection Act, infected patients in Germany are prohibited from staying and working in communal facilities even if they are suspected. Therapy is preferably carried out using special creams, emulsions or tablets and a range of hygiene measures.

Other mite diseases in humans are known as acariasis . The Italian doctor Giovanni Cosimo Bonomo is considered to be the discoverer of the connection between mite infestation and the previously known scabies in the 17th century.

Scabies in animals is colloquially known as mange , although other mites also occur here. In addition to the hair follicle mites , most of these parasites can also attack humans as false hosts and cause pseudo-scabies or deceptions , medically pseudoscabies .

Sarcoptic mite

Cause and development of the disease

Scabies mites have an obligatory parasitic way of life. As members of the arachnids , they have eight legs arranged in pairs. It is typical of the mites that both rear pairs of legs do not protrude beyond the edge of the compact body and, just like the two front pairs of legs, are stub-shaped. The size of the female specimens is about 350 × 280 µm , male mites reach length × width 240 × 150 µm. It is characterized by the presence of adhesive disks, which sit on an undivided handle and are attached to the legs. Female mites only carry these organs on the three front pairs of legs, in males all legs.

The development of the mites runs from the egg through a larval and two nymph stages to the adult animal and takes about 14 days in the male and a week longer in the female. Only the females create drill channels in the horny layer ( stratum corneum ) of the epidermis (upper skin), in which they deposit their eggs and their feces . The male mites migrate mainly on the surface of the skin in search of females. A female mite can live up to 60 days. Outside the host body, the itch mites rarely survive longer than 48 hours.

Scabies is often associated with unsanitary conditions and neglect . Itch mites do not necessarily have to do with unsanitary living conditions, but spread - similar to lice - where many people come together. Nursing homes and nursing homes are particularly affected, but also kindergartens, schools and even hospitals. Scabies is transmitted from person to person through skin contact. It is assumed that there is an indirect path of infection by means of living or clothing textiles.

With an intact immune system and good hygienic conditions, the body's immune reaction keeps the number of mites at a relatively low level. If there is immunosuppression , e.g. B. by an infection with the HI virus , the mites can multiply explosively. The resulting clinical picture, scabies norvegica , differs significantly in appearance, intensity and infectiousness from classic scabies.

In 2016, a survey by the Rheinische Post at the health authorities of North Rhine-Westphalia showed that the number of scabies infections has increased significantly since 2013. Children in day care centers, residents of old people's homes and people who are housed in refugee shelters are particularly affected.

From 2017 to 2018, the number of cases of scabies in Hesse more than doubled to 424 cases.

Symptoms

A mite bore hole on the foot. The mite can be seen in the top left as a black point.

Scabies mites prefer parts of the body with a thin horny layer and a high relative body temperature . It mainly affects the spaces between the fingers, wrists, buttocks, genitals, elbows, armpits, navel, the area behind the ears, girdle area, knees, bends of the joints, feet and ankles. In small children and in scabies norvegica ( see above ) the neck and head can also be affected.

After the initial infection, the disease is usually asymptomatic for the first two to five weeks. After this time there is an immune reaction against mite products (mite protein, eggs, feces) and a typical itchy skin reaction associated with it. In addition, there may be a burning sensation on the skin, especially when it is warm (e.g. when taking a warm shower).

The secretions of the mites produce vesicles, vesicles, papulovesicles, papules , pustules, wheals , infiltrations and, as secondary lesions, crusts , scratches and boils . Also unaffected parts of the body, e.g. B. the face, can show allergic reactions. Itching in places that are not affected does not necessarily speak against a scabies infection. This often generalized itching with only individual locally visible skin changes is characteristic of scabies. The often very intense itching usually only occurs at night with light mite infestation, as the warmth of the bed lowers the itching threshold. By scratching the papules / vesicles - often involuntarily - skin lesions arise .

Scabies can occur in different forms and is therefore divided into special special forms:

  • Well-groomed scabies
  • Bullish scabies
  • Nodular scabies
  • Scabies norvegica (crustosa)

Well-groomed scabies : With this form of scabies, the sufferers practice intensive body care to hide the visible symptoms. Cosmetics are used for this. A clear diagnosis can often be difficult to make due to the skin changes.

Bullous and nodular scabies : A strong expression of strongly itchy, reddish-brownish nodules without mite infestation is characteristic of these types of scabies. However, after successful treatment, the nodules can remain visible for months in individual cases. In bullous scabies, blisters form. This form of scabies occurs more frequently in children and adolescents.

Special form Scabies norvegica (bark scabies) in a patient whose immune system is weakened by AIDS

Bark scabies : The Scabies norvegica (crustosa) is extremely different from all other forms of disease, as it comes here to a very strong mite infestation. Reddening of the skin known as erythroderma occurs all over the body . In addition, numerous scales form, which reach small to medium size. Thick layers of cornea ( hyperkeratosis ) develop on the palms and feet. The thick crusts that mainly develop on the fingers, elbows, backs of the hands and wrists can measure up to 15 millimeters. The skin under these crusts is red and moist and shiny. As a rule, crusts are limited to a certain area of ​​the body. But bark scabies can also spread to the soles of the feet, back, ears and scalp. However, the clearest symptom of scabies, pruritus, can be completely absent from bark scabies.

Complications can occur in the form of a mostly staphylogenic superinfection . This can cause abscesses , lymphangitis and sepsis .

therapy

Already in the Middle Ages an ointment treatment of scabies and other skin diseases with inflamed, oozing, painful erosions or excoriations is documented. A therapy for children from the 3rd month of life as well as for adults is the use of a 5 percent permethrin cream , which often kills the itch mites after a single application. There is no approved therapy for younger children, so permethrin 5% can also be used here in the absence of an alternative. Permethrin is an insecticide from the group of pyrethroids . Despite being more effective against mites, it is less toxic to humans than the lindane preparations used previously. Permethrin treatment is tolerated very well. In order to cure the scabies, the female mites on humans must be killed. For this, a comprehensive creaming with the permethrin cream is necessary. There is clear evidence of development of resistance to permethrin.

Treatment with crotamiton is also possible, although this is significantly less effective.

Ivermectin , a macrolide from the group of avermectins , which has to be taken orally twice every two weeks, but is not yet widely available , has been used increasingly around the world in recent years .

Another topical treatment is the use of an emulsion containing benzyl benzoate . Before the treatment begins, the body should be cleaned thoroughly, after which the emulsion can be rubbed in from head to toe. This emulsion should be applied for three consecutive days, after which the treatment must be discontinued - even if itching persists . Take a full bath on the fourth day, contact a doctor if itching persists. If you have sensitive skin (especially people with perfume allergies or other skin allergies), a hypersensitivity reaction may occur. Since this remedy is very inexpensive, it is still the preferred choice for the treatment of scabies in Eastern Europe. Western European studies indicate an efficiency of 50%. However, an independent study by the WHO found benzyl benzoate to be much more effective.

Tea tree oil - as a herbal alternative - is said to have a certain effectiveness. It should not be used for pet treatment due to potential side effects. Various avermectins are available for systemic therapy in animals .

The co-treatment of the contact persons is essential. Since it can take about 6 weeks from infection to the first visible signs of the disease, the contact persons of an infected person can already be infected without noticing. Therefore, parallel treatment is recommended not only for the sick person, but for all persons living in the same household, as well as all persons with whom the person concerned has had sexual intercourse in the last 6 weeks (since the infection requires brief skin contact, one usually infects one's own family or people with whom you share a bed). People who do not fall into this group of people, but who z. B. were often visiting the apartment of the person concerned, are not treated, but should be informed that an infection may have occurred in principle (e.g. by sitting on a couch that has not been vacuumed, using a blanket, etc.) and you should If symptoms begin (itching all over the body, duct-like skin changes, especially in the hand area), consult a doctor.

Equally important is the killing of the mites that v. a. collect in the clothes and bedclothes of the person concerned, parallel to the treatment of the skin, otherwise you will be infected again from your own clothes. The laundry can be cleaned up by washing it at 60 ° or storing it in sealed plastic bags at room temperature for 4 days.

The body does not develop immunity to scabies. After successful therapy you can get infected again at any time. Since people in the vicinity are usually also affected, one should be very careful with closer physical contact until about eight weeks after the last person in the vicinity is symptom-free. The ping-pong effect often occurs . H. someone who has already been cured of scabies is infected again in their circle of friends. A close follow-up check up to months is always required to be sure that the disease has been cured.

As a tropical disease

Scabies is increasingly rare in the developed world, but it remains an endemic , widespread disease in the tropics with 130 million people infected worldwide. The WHO therefore initially classified scabies as a neglected tropical disease in 2013 , but, unlike the other 17 diseases, did not develop a program. Especially on the islands of the Pacific Ocean ( Oceania ), scabies is very common with a prevalence of up to 40% and impetigo as a frequent bacterial superinfection in up to 25%. Individual treatment is not very effective in the tropics, as new infections from family members or friends are very common.

Since a Panamanian study in 1991, a permethrin cream has been recommended for group therapy . In an Australian- Fijian cluster randomized comparative study ("SHIFT" study) with over 2,000 participants on several smaller islands in the Eastern Division of Fiji, a population-wide therapy with topical permethrin and one with ivermectin in tablet form were compared with a control group in which only Patients with scabies were treated. This showed a significant superiority of the population-wide therapy with a relative reduction of the prevalence after one year by 49% in the control group with individual treatment , but 62% in the group therapy with permethrin and 92% in the ivermectin group therapy, although this was only given once and a second dose was given after seven to fourteen days only for crusted scabies. The prevalence of impetigo was also significantly reduced with a relative prevalence reduction of 32% in the control group, 54% under permethrin and 67% under ivermectin. No serious or permanent adverse effects were observed.

Legal aspects

This article or paragraph presents the situation in Germany . Help us to describe the situation in other countries.

The law for the prevention and treatment of infectious diseases in humans ( Infection Protection Act, IfSG) requires community facilities according to § 33 (schools, day care centers, homes, holiday camps, etc.) to take special measures in the case of scabies, among other things. According to Section 34 (1) IfSG, employees with scabies are not allowed to work in communal facilities where they are in contact with the cared for. Supervised people with scabies are not allowed to use the rooms of the community facility and are not allowed to participate in the events of the community facility. According to Section 34 (5) IfSG, employees and those cared for with scabies or their custodians must inform the management of the community facility immediately. According to Section 34 (6) IfSG, the management of a community facility must provide the responsible health department with information about the matter relating to the disease and person-related.

See also

literature

  • Stefan Winkle: About scabies as a "story of errors". In: Hamburger Ärzteblatt. Hamburg 2004.5, pp. 214-225.
  • Wolfgang U. Eckart : scabies (lat. Scabies). In: Werner E. Gerabek , Bernhard D. Haage, Gundolf Keil , Wolfgang Wegner (eds.): Enzyklopädie Medizingeschichte. De Gruyter, Berlin / New York 2005, ISBN 3-11-015714-4 , p. 786 f.

Web links

Commons : Scabies  - Collection of pictures, videos and audio files

Individual evidence

  1. ^ E. Kämmerer: Scabies . In: Deutsches Ärzteblatt , 115, 15 S, pp. 700–702
  2. ↑ Peter Riethe : Scabies and the meaning of the "suriones" in Hildegard von Bingen. In: Sudhoff's archive. Volume 90, 2006, pp. 203-218.
  3. ^ A b Hans Christian Korting: Scabies . In: Journal of the German Dermatological Society , 2007, 5, p. 424 ff. Doi : 10.1111 / j.1610-0387.2007.06298_supp.x
  4. ↑ a b c Andreas Plettenberg, Wilhelm Meigel, Helmut Schöfer: Infectious diseases of the skin. Basics, diagnoses and therapy concepts for dermatologists, internists and pediatricians . Thieme, Stuttgart 2010, ISBN 978-3-13-137733-3 , p. 384-385 .
  5. ↑ The number of people suffering from scabies is increasing in North Rhine-Westphalia , last accessed on November 29, 2016.
  6. ↑ More cases of scabies in Hesse , last accessed on January 21, 2019.
  7. ↑ apotheken-umschau.de
  8. ^ Gundolf Keil: The pharmacopoeia Ortolfs von Baierland. Its scope and influence on the 'Cirurgia magistri Petri de Ulma'. In: Sudhoff's archive. Volume 43, 1959, pp. 20–60, here: p. 57, note 3 (on “Räudensalbe”).
  9. ↑ a b c d e Sunderkötter et al: S1 guidelines for diagnosis and treatment of scabies. (PDF) Retrieved October 9, 2017 .
  10. ^ Editor PZ: Oral ivermectin available in Germany. In: PZ issue 18/2016. Pharmaceutical newspaper PZ, May 2016, accessed on August 5, 2016 .
  11. ↑ Comparative study between benzyl benzoate and ivermectin in scabies (PDF; 534 kB) WHO (English)
  12. ↑ SF Walton et al. a .: Acaricidal activity of Melaleuca alternifolia (tea tree) oil - in vitro sensitivity of Sarcoptes scabiei var hominis to terpinen-4-ol. In: Archives of Dermatology . 2004, Volume 140: pp. 563-566. PMID 15148100 ISSN  0003-987X
  13. ↑ BfR Opinion No. 029/2007 of September 14, 2007 (PDF)
  14. ↑ RKI - RKI advice for doctors - Scabies (scabies). Retrieved October 9, 2017 .
  15. ↑ who.int prevalence according to WHO information
  16. ↑ Bart J. Currie: Scabies and global control of neglected tropical diseases, New England Journal of Medicine 2015, Volume 373, Issue 24, December 20, 2015, pages 2371-2372; doi: 10.1056 / NEJMe1511805
  17. ↑ Lucia Romani, Margot J. Whitfeld, Josefa Koroivueta et al .: Mass drug Administration for scabies control in a population with endemic disease . New England Journal of Medicine 2015, Volume 373, Issue 24, December 10, 2015, pp. 2305-2313, doi: 10.1056 / NEJMoa1500987