MOLLUSCUM CONTAGIOSUM

Introduction

Mollusum contagiosum (MC) is a common virus infection caused by a so-called pox virus. The appearance and history of the disease are not unlike those of viral warts, but the viruses that cause the two disorders are quite different.

Symptoms

Little white or pink bumps or papules develop on the skin. The number of bumps (medically called mollusca) that occur varies enormously and is unpredictable. Each of the mollusca contains a central depression. The face, neck, armpits and trunk are often involved but any area of the body may be affected. Involvement of the genitalia may occur in adults.

Prevalence

MC is most commonly seen in children but also may affect young adults. Because it is infectious small outbreaks can occur within families. Children with asthma or eczema (atopics) seem particularly prone to develop extensive infections. MC may also be more common in those using steroid creams to treat other skin disorders.

Development

Eczematous patches often appear around mollusca. If left alone individual papules clear after 6 to 9 months and the disease as a whole clears in a year or two. Once MC has come and gone those affected remain permanently immune.

Tests

Normally MC is easily recognised by a dermatologist and no tests are required. Occasionally single mollusca may be confused with moles or other harmless skin lumps. Examination of a skin specimen under the microscope will easily distinguish between these possibilities.

Treatment

Many simple destructive procedures such as squeezing with fine forceps or freezing with liquid nitrogen will lead to a rapid resolution of mollusca. This type of treatment is fine for adults or older children but few patients under the age of 8 will tolerate painful measures of this type. Sometimes applying a wart paint, such as Salactol, once weekly will be helpful but wart paints must be kept well away from the eyes. There is a local anaesthetic cream (EMLA) which if applied will reduce pain sufficiently to enable small numbers of mollusca to be frozen. It is usually best to wait for MC to go on its own if the patient is a child under eight.