Clinical case report for family physicians

molluscum _contagiosum

A 12-year old boy with atopic dermatitis complains of multiple popular lesions over his body and upper limbs. They are mildly itchy and the number has been increasing over the past few weeks. Physical examination reveals multiple flesh-color papules, 1-5 mm in diameter distributed over both flank and upper limbs; some of the papules have a depressed centre.

Molluscum contagiosum (MC) is a viral infection of the skin or occasionally of the mucous membranes. It is caused by a DNA poxvirus called the Molluscum contagiosum virus (MCV). MC can affect any area of the skin but is most common on the trunk of the body, arms, and legs. It is spread through direct contact or shared items such as clothing or towels.

The virus commonly spreads through skin-to-skin contact. Handling objects that have the virus on them (fomites), such as a towel, can also result in infection. The virus can spread from one part of the body to another (auto-innoculation) or to other people. Molluscum contagiosum is contagious until the bumps are gone (which, if untreated, may last up to 6 months or longer).

Diagnosis is made on the clinical appearance of the papules which are flesh-colored, dome-shaped, and pearly in appearance. They are often 1–5 millimeters in diameter, with a dimpled center. They are generally not painful, but they may itch or become irritated. The diagnosis can be confirmed by excisional biopsy. Histologically, Molluscum contagiosum is characterized by Molluscum bodies in the epidermis above the stratum basale, which consist of large cells with abundant granular eosinophilic cytoplasm (accumulated virons), and a small peripheral nucleus.

Individual Molluscum lesions may go away on their own and are reported as lasting generally from 6 to 8 weeks, to 2 or 3 months. Treatment is often unnecessary depending on the location and number of lesions, and no single approach has been convincingly shown to be effective. For those who need treatment, trichloracetic acid, imiquimod, cryotherpay, curettage, laser has been used.