Answers to Q1

Molluscum contagiosum (MC) is caused by a DNA poxvirus of the same name, and is largely a disease of humans. Infection follows contact with infected persons or contaminated objects. MC virus transmission through direct skin contact between children sharing a bath and between athletes sharing gymnasium equipments and benches has been documented. Between 5-18% of children show signs of clinical disease, increased in patients with HIV infection, with severity inversely proportional to CD4 count. In the general population the prevalence of MC is 33% in developed countries. Even though reinfection is common, the virus is not strongly immunogenic and infrequently induces antibody formation that can be detected by several serological tests such as complement fixation test. It was first described by Bateman in 1817, its viral nature in 1905 by Juliusburg and its infectious nature by Paterson in 1941. Four types of MC have been identified by restrictive endonuclease analysis of the viral genome namely MC I, II, III and IV.

Type I causes 96.6% of infections in non-HIV-infected individuals, while type II causes 60% of infections in HIV-infected patients. Types III and IV are rare. It is more prevalent in tropical areas and transmission may be related to poor hygiene, warmth and humidity. It is more common in whites than other races and more common in males than females. It peaks among pediatric age group due to casual contact and among young adults during sex. Use of school swimming pools correlates with childhood infections. MC infection normally resolves without therapy within 6-9 months, but may persist for 3-4 years.

Infection in adults is usually sexually transmitted with lesions limited to the perineum, lower abdomen or buttocks. Complications of MC are mainly irritation, inflammation and secondary infection. Lesions on eyelids are associated with follicular or papillary conjunctivitis. Bacterial super-infection in HIV-infected patients is associated with Staphylococcus aureus and Pseudomonas aeruginosa with abscess formation. MC may be widespread, persistent and atypical in immunocompromised patients.

Patients on immunosuppressive medication may have more extensive infections, which are difficult to mangage. Patient education as to the benign nature of the disease is important to allay the distress it can cause in patients or parents of infected children. It is unclear whether condoms and other barrier methods provide adequate protection against transmission, thus safe sex and abstinence in adolescents and adults should be encouraged. MC can occur on penis, scrotum, inner thigh or any other parts of the body.

Question 2: What is the diagnosis and other investigations would you do to confirm the diagnosis?

Answer to Q3

In healthy patients who are not immunocompromised, MC infection is self-limited and heals spontaneously after several months. The most important precautionary measure in both children and adults is to reduce autoinoculation or transmission to close contacts and to improve the clinical appearance. Topical application of medications such as Podophylin, Potassium hydroxide, Tretinoin cream and Cantharidin, radiation therapy and/or surgery is recommended. These include cryotherapy or curettage of individual lesions in adults. Therapy with lasers, imiquimod and antiviral therapy or combinations of both have been successfully used. Treatment may result in scarring or post-inflammatory pigment changes. Multiple treatment sessions may be necessary because of the recurrence of treated lesions and/or appearance of new lesions due to autoinoculation. Once the lesions have completely resolved MC virus doesn’t remain latent. I can be completely cured. However, there is no permanent immunity to the virus one may get infected again upon contact to an infected person.