Identifying and Treating MC
By William L. Miller, OD, PHD, FAAO
Small, waxy, and often flesh-colored skin lesions on the eyelids may be indicative of molluscum contagiosum (MC). Lesions are typically raised and umbilicated with a central indentation and are caused by a double-stranded, large DNA pox virus. Found in children and young adults, it can commonly lead to a chronic follicular conjunctivitis. The cornea may also demonstrate punctate keratitis with subepithelial infiltration and pannus.
Immunocompetent children are usually exposed through infected clothing, towels, or bed linen. It has been reported that children up to age 14 represent 90 percent of MC occurrences (Pannell et al, 2005). Children demonstrate MC lesions mostly in the upper torso region. Young adults are typically affected by transmission sexually with lesions affecting the lower abdomen and lower torso.
In immunocompetent patients, MC lesions tend to be unilateral, smaller, and less frequent than in immunocompromised patients. As an opportunistic infection, it is found more commonly in AIDS patients as a result of the severely depressed T-lymphocyte-mediated immune response from the HIV infection. Unlike immunocompetent patients, AIDS patients who have MC typically do not have conjunctival hyperemia or exhibit follicular conjunctivitis. Additional nodular, pink lesions on the conjunctiva, although rare, are associated with AIDS patients. A few reports have even linked the appearance of MC lesions as the first clinical manifestation of HIV disease (Leahey et al, 1997; Biswas et al, 1997).
MC is self-limiting in immunocompetent patients with a resolution time of between three months and 12 months. You may choose to observe the MC lesions over time to monitor resolution, however if the cornea or conjunctiva become involved, prompt treatment may be indicated.
No antiviral treatments exist for MC. In AIDS patients, the lesions may recur within six to eight weeks after treatment, which matches the virus' incubation period. This recurrence can be resolved in AIDS patients undergoing highly active antiretroviral therapy (HAART), which uses at least three antiretroviral agents as a therapeutic cocktail. HAART allows for a reconstitution of immune function and lessens the severity of any future MC attacks.
Treatments consist of topical agents and surgical approaches. Topical application of phenol and trichloroacetic acid as well as serial application of liquid nitrogen has been suggested (Janniger and Schwartz 1993; Williams and Webster 1991). Incision with or without curettage as well as cryotherapy have been effective (Biswas and Sudharshan, 2008). Other treatments are electrodissection and Tretinion 0.1% cream.
Therapeutic agents used in the dermatology field for MC lesions elsewhere on the body can include imiquimod 5% cream, cantharidin 0.9%, and potassium hydroxide (Cantisani et al, 2012; Kose et al, 2012; Marsal et al, 2011; Seo et al, 2010). Cantharidin is a solution that contains collodian and acetone that causes severe blistering. Imiquimod is an immune response modifier that causes an increase in interleukin-12 and interferon. Although expensive, it may be suitable for application via home therapy.
As mentioned with cantharidin, many of the aforementioned treatment protocols have varying complications. Potassium hydroxide in children may be a more noninvasive approach to reduce MC. Recognition and proper referrals are necessary with an MC diagnosis. Coordinated care with a dermatologist, internist, or other health professional is necessary in affected patients. CLS
For references, please visit www.clspectrum.com/references.asp and click on document #198.
|Dr. Miller is an associate professor and chair of the Clinical Sciences Department at the University of Houston College of Optometry. He is a member of the American Academy of Optometry and the AOA where he serves on its Journal Review Board. He is a consultant or advisor to Alcon and Vistakon and has received research funding from Alcon and CooperVision and lecture or authorship honoraria from Alcon and B+L. You can reach him at firstname.lastname@example.org|