This summary discusses adult patients. Molluscum contagiosum in children is addressed separately.

Molluscum contagiosum is a viral skin infection caused by a DNA poxvirus. It manifests as smooth, firm papules with a central umbilication. Genital lesions are most commonly spread by sexual contact, and papules are most commonly seen on the shaft of the penis. However, lesions may also be found on the scrotum, in the pubic area, and on the inner aspect of the thighs.

Molluscum contagiosum may also be spread by direct contact (most often in children) and autoinoculation (ie, shaving). Infections have also been associated with swimming pool facilities via fomites.

Many cases are asymptomatic, but there can be surrounding irritation and pruritus. In the immunocompetent host, the disease tends to be self-limited, but papules may persist for several months and up to 2 years before disappearing.

In cases of underlying immunodeficiency, such as HIV disease, molluscum may be widespread or large, atypical papules and/or plaques may be seen.