Molluscum contagiosum is a parasitic lesion of the skin and mucous membranes with a specific virus. It is manifested by painless nodular rashes with an umbilical depression in the center, from which, when pressed, the curd content is released. When this secret gets on the skin or mucous membranes, self-infection occurs and the disease is transmitted to contact persons. Has a tendency to relapse, is often fixed together with other infections, including HIV infection.
ICD 10
B08.1 Molluscum Contagiosum
General information
Molluscum contagiosum is a chronic highly contagious skin disease, the causative agent is included in the smallpox group of viruses – Molluscipoxvirus. According to the international classification of diseases, contagious mollusc does not belong to venereal diseases, however, WHO includes contagious mollusc in the list of sexually transmitted infections. Persons of both sexes are susceptible to infection, regardless of age groups, but people who are promiscuous in sexual contacts and children fall into the risk group.
Pathogenesis
Molluscum contagiosum is a benign neoplasm of the skin; DNA virus synthesis occurs in the keratinocytes of the epidermis, after the virus multiplies in the host cells, the activity of T-lymphocytes is blocked, and therefore there are no immune cells when affected, which explains the immune tolerance that favors the pathogen during infection.
Causes
Contagious mollusc is a disease that only humans are susceptible to. Infection occurs when a sick person comes into direct contact with a healthy person, but there is an indirect way of infection – through contaminated objects.
Adults are mainly infected during sexual contact, infection occurs due to the contact of the skin of partners, and not through coitus, which is why some international medical organizations do not classify a molluscum contagiosum as a group of sexually transmitted infections. The affected area during sexual intercourse is usually the perineum, the inner surface of the thighs, the lower abdomen, the external genitals.
When infected by domestic means, there is no specific localization of the molluscum contagiosum, neoplasms can be found on any skin areas. The presence of skin lesions and microtrauma is a favorable condition for inoculation of the virus.
Cases of infection are usually isolated, despite the high contagiousness of the mollusk, but in kindergartens the lesions can be endemic.
Factors such as crowding, skin contact, and a humid atmosphere favor dissemination. The incubation period of a molluscum contagiosum ranges from several weeks to several months, so it can be difficult to determine the source of infection. After the appearance of clinical manifestations, the molluscum contagiosum spreads through the body by self-infection. Cellular immune deficits, congenital and acquired, contribute to infection, in people with HIV infection, the incidence of molluscum contagiosum is several times higher.
Since the causative agent of a molluscum contagiosum is a DNA virus, it is impossible to achieve a complete cure, but modern methods of exposure allow for long-term and persistent remission.
Symptoms
After the incubation period, single painless dense nodules of a rounded shape appear on the skin, the color of the skin affected by a molluscum contagiosum is usually not changed or acquires a pink hue, sometimes a waxy or pearlescent shine may be noted. Then there is an increase in the number of elements of a molluscum contagiosum due to self-infection. The size of the eruptions from millet grain to pea, sometimes when the elements merge, giant molluscum contagiosum can form, they look like hemispherical papules with a sunken central part.
Nodules are located everywhere on the body, but since self-infection occurs through the hands at the second stage of the development of a molluscum contagiosum, the skin areas that are most often touched are affected. This is the face, neck, upper torso and the hands themselves. The eruptions of the molluscum contagiosum are disorderly, and their number sometimes reaches several hundred, hand friction and involuntary scratching increase the number of dissemination.
When pressed with tweezers or accidental damage to a molluscum contagiosum, a white mushy mass is released from it, which consists of keratinized cells and lymphocytes. But it also contains inclusions of molluscous bodies, which is why the disease got its name. There are no subjective sensations, but some patients with contagious mollusc note itching and slight infiltration, which happens when a secondary infection is attached.
With atypical forms of molluscum contagiosum, there may not be a characteristic concave center on the rashes, and the elements themselves may be very small in size. Profuse forms of contagious mollusc are diagnosed in children with atopic dermatitis, in children with leukemia and immunodeficiency, as well as in HIV-positive patients. As a rule, the course of a molluscum contagiosum passes without complications, aseptic and purulent abscesses of the skin around the affected area are possible. In very rare cases, superinfection is observed, after which scars remain.
Diagnostics
The diagnosis is made by a dermatologist on the basis of a clinical examination of the patient, in doubtful cases, histological examination is resorted to for diagnosis, during which molluscan corpuscles are found in the cytoplasm of epidermal cells. It is necessary to differentiate a molluscum contagiosum with lichen planus, multiple keratoacanthoma and warts.
Treatment
Surgical removal using curettage after preliminary local anesthesia under the film gives a good effect, since a large number of molluscum contagiosum can be removed in one session due to the almost complete absence of pain syndrome during the procedure. Usually, one session is performed per month, and a complete clinical recovery occurs in a few months. With this method of treatment, the contents of the nodules do not remain, traumatization of the skin is minimal, after curettage, in some cases, electrocoagulation of the affected areas is indicated.
Removal of skin formations of a molluscum contagiosum is possible by cryodestruction or by radio wave method. Laser removal is also used. If there are few rashes of a molluscum contagiosum, then chemotherapy drugs give a good effect, but it is not recommended to use them for a long time because of the irritating effect on the skin. With minor dissemination, UV irradiation with therapeutic ultraviolet radiation of the affected skin and the use of creams with acyclovir are indicated for all patients with contagious mollusc.
The method of applying Tuberculin to the affected area with a molluscum contagiosum is especially often used in pediatric dermatology, as it is painless. This technique is new, and therefore there are no accurate statistical data on its effectiveness. But children should be pre-vaccinated with BCG or isoprinosine.
Prevention and prognosis
In most cases, the prognosis for infection with a molluscum contagiosum is favorable, the exceptions are patients with immunodeficiency conditions. Prevention consists in observing personal hygiene both in public places and at home. It is necessary that each family member has his own washcloth and other bath accessories. When diagnosing a molluscum contagiosum in children, infected children are isolated and quarantined for the duration of the incubation period with daily preventive examination of the entire children’s collective and service personnel.