Molluscum Contagiosum

The lesions appear in the form of small papules of 2-5 mm size. Papules of size greater than 15 mm diameter are rarely seen. These papules are spherical or round in shape, firm, smooth- surfaced and have a characteristic central dimpling.

The sites of these papules are different for children and adults. Although the papules are red and swollen in appearance but no local tenderness has been noted. In children, the lesions commonly occur on the chest, arms, legs, and face. Lesions on the mucous membranes such as nose, lips and buccal mucosa are rare. The genitalia, gluteal areas, perineum and inguinal areas are mainly affected in adults as the lesions are mostly sexually transmitted.

These lesions are severe and extensive in individuals with a compromised immunity such as in HIV. The infection lasts for around 2 months but the disease in general takes about 2 years to resolve completely [7].

Molluscum contagiosum is diagnosed through clinical presentation and physical examination alone. The hallmark of diagnosis is done by identification of the molluscum contagiosum inclusion bodies from the specimen of the lesion obtained, through histopathological examination. The blood tests are usually not required except in suspected cases of HIV, where in it is the only symptom.

As it is a self limiting disease, treatment is not required and in healthy subjects, the lesions disappear in a 3 month period.

Treatment is advised to prevent autoinoculation and limit the transmission of the infection. This is achieved by various methods such as curettage, cryotherapy, topical antiviral applications and surgery.

In immunocompromised patients, treatment is difficult and laser techniques, antiviral therapy along with imiquimod is recommended. Imiquimod application causes stimulation of immune response by producing interferons [8] [10]. The ointment of 1% concentration is to be applied 3 times daily for 4 weeks on the lesions and that of 5% once daily at bedtime. In patients with HIV, antiretroviral therapy is found to be much more efficient and useful. The drugs are mainly ritonavir, cidofovir and zidovudine. A new drug called Veregen is prepared from the extract of the green tea. This drug is available in an ointment form and is to be applied on the affected areas 3 times daily [6].

In a study conducted in children for treatment of molluscum contagiosum, few children were treated with cantharidin, few others had undergone curetting, few with imiquiod and the rest with salicylic acid. Of these, curettage therapy was found to be more efficient and acted well. This is because cantharidin has a strong vesicant action and acts by exfoliating the entire lesion. This treatment has also not been acknowledged by the FDA.

Salicylic acid is a caustic agent hence results in inflammation and desquamation. It also has the quality to adhere and coat the lesion, and therefore the infection doesn’t spread and remains limited to that area itself.

Cryotherapy is frequently used by many therapists, especially in elderly age group. This procedure involves freezing of the lesions which causes thinning of the adjacent skin. This is repeated after a few weeks until the disease disappears. Cryotherapy leads to loud sounds and so could be frightening to younger children. Also, the pain element is relatively high during the procedure. Pulse dye laser (PDL) therapy is found to be successful and is routinely performed. This treatment proves to be very efficient and there have been drastic reductions in the number of molluscum contagiosum lesions.

Molluscum contagiosum is a self remitting disease; hence the prognosis is very good. The rate of recovery is different for different individual. In healthy immunocompetent individuals, the recovery occurs by approximately 2 years. There is no death noted till date.

The morbidity percentage is higher, especially in HIV or other immunocompromised patients as they have extensive and wide spread areas infected. Though there is a complete remission; chances of recurrence of the infection is about 40%, which is also estimated due to aggravation of the current infection or new lesions appearing after an extended no infection period.

The lesions regress totally with no long lasting skin defect; however skin scarring and disfiguring of skin has been noted [6].

Molluscum contagiosum is caused by Molluscum Contagiosum virus (MCV). This virus has a high molecular weight and is a DNA virus. After reaching the epithelium, it enters the cytoplasm and multiplies in it. It is found that MCV can survive and develop only in human skin and not in any tissue culture or eggs.

Personal contact with the infected objects such as personal items, razors, beddings, towels, napkins spreads the infection. Also, the lesion spreads locally if the lesions are touched or manipulated. This phenomenon is called as autoinoculation. Spread via swimming pools has been reported [1].

Molluscum contagiosum infection is prevalent throughout the world and is one of the most common skin infections. In the United States, it occupies 1% of all skin infections. Studies reveal that the rate of this infection has been increasing.

The tropical regions show the highest infection rates. Mali has been reported to have about 5% of total prevalence with maximum age group of children getting affected [3]. The incidences grow with increasing age; lowest in children up to 2 years and high in adults more than 40 years. Certain areas like Fiji, and Africa, are repeatedly affected.

Studies have associated climatic seasonal factors such as humidity and warmth as the likelihood to the prevalence of this infection, as there is a possibility of young age group being moderately dressed and hence the chances of them transmitting the infection rise. Men are frequently affected. Infants are hardly infected and those more than 5 years are highly infected [4].

Mollluscum contagiosum virus produces cytoplasmic inclusions and enlargement of the cells in the epithelial layer of the skin. The virus disperses the infection from the basal layer of epidermis to the spindle and the granular layers of the epidermis during the 8 weeks of the infection period.

At the cellular level, the infected cells undergo intense destruction and distortion resulting in formation of huge hyaline bodies called molluscum bodies or Henderson-Paterson bodies [5]. These bodies have a typical structure which looks like a smooth papule with a central white dimple. It has been noted that these lesions have a possibility to get inflamed and develop edema with proliferation of blood vessels and monocytic and lymphocytic infiltration.

Self manipulation or scratching of the lesions should be avoided as it causes local spread. Observe self hygiene and repel from any physical contact. Molluscum contagiosum is transmitted through sexual route, so care must be taken and abstinence is recommended or possibly to use a condom. The disease is transmitted even though fomites like cupboards etc., so direct contact with it must be avoided.

Patients are advised to maintain usual hygiene and avoid physical contact with other individuals. They are informed not to share beddings, bath towels, sports equipment, and swimming pools with other people. Touching or scrapping of the local lesions should be avoided to minimize autoinoculation [1] [8].

Molluscum contagiosum is a common cutaneous viral infection. It was discovered in the early nineteenth century by Dr. Bateman. Molluscum contagiosum is an infection which spreads from person to person and it is prevalent worldwide. This infection is found in the adult age group as well as in children.

The virus invades the host from the epidermal layer of the skin through small breaks appearing in the hair follicles. As only the epidermis is involved, it is also called as epithelioma contagiosum or dimple warts. The lesions appear as papules which are pearly and smooth occurring in clusters.

Like all contagious infections, molluscum contagiosum also gets transmitted from person to person. Care must be taken to avoid physical contact with family and other members. The area should be enclosed in a thicken gauze piece or bandage; scrapping or touching must be avoided in order to avoid the local spread. Individual must refrain from sexual activity during the infection if the lesions involve the genital area.

Molluscum contagiosum is a self remitting disease, so if left untreated it will resolve on its own. Complete recovery takes about 6 months. The lesions can culminate into deep scarring after the disease remission. Local surgery, lasers, curetting are different recommendations for treating in order to cut the duration and prevent disfiguring of the skin [11].

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