How to Diagnose Molluscum Contagiosum

Molluscum contagiosum is an infection by the virus of the same name. It is a benign disease that affects the skin, especially the genitals, and is sexually transmitted. Molluscum contagiosum resembles smallpox microscopically but has a latent period as long as six months. It can occasionally progress and cause lesions in the presence of a secondary infection or break in the skin. The following steps will show how to diagnose molluscum contagiosum.

Instructions

1. Expect the usual presentation of molluscum contagiosum to be a solitary or group of flesh colored papules with a central pit. They are typically painless and resolve spontaneously but may progress into hard red pustules that are painful. The patient history may reveal an infected family member or sexual partner.

2. Observe the advanced disease to cause well-defined papules 2 to 6 mm in diameter that resolve as new ones appear elsewhere. The lesions show the usual signs of bacterial infection if they become super infected. They can become more widespread and grow to 10 to 15 mm in immunocompromised patients.

3. Make the diagnosis of molluscum contagiosum clinically in most cases based on the location and appearance of the lesions.

4. Examine the suspect tissue microscopically. A thin smear stained with Giemsa, Gram or Wright should show cells infected with Molluscum contagiosum. An electron microscope is needed to detect the viral particle. A biopsy should be performed and stained with hematoxylin and eosin to confirm the diagnosis, if needed.

5. Detect the antigens of Molluscum contagiosum with fluorescent antibodies.