Molluscum contagiosum - Anogenital in
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 tend to be located on the hair-bearing regions of the mons and inguinal creases. The labia majora, inner thighs, and buttocks may also be involved.
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.
B08.1 – Molluscum contagiosum
40070004 – Molluscum contagiosum
Differential Diagnosis & Pitfalls
- Hidradenoma can be umbilicated although much larger.
- Condyloma acuminatum can look similar if small.
- Herpes simplex virus lesions can resemble molluscum with a central umbilication, but lesions are fluid-filled rather than solid as in molluscum contagiosum.
- Milia and epidermal cysts
- Lobular capillary hemangioma (pyogenic granuloma) is obviously vascular with frequent ulceration.
- Lichen planus lesions are purple, pruritic, planar papules that can also spread in a linear pattern.
- Papular acantholytic dermatosis
- Sebaceous adenitis
- Fordyce spots
- Vestibular papillomatosis