Molluscum Contagiosum

Biopsy proven molluscum contagiosum. (Courtesy Kimberly Reed, O.D.)

Molluscum contagiosum in an HIV patient. (Courtesy Kimberly Reed, O.D.)

Signs and symptoms: Molluscum contagiosum are raised lesions found around the ocular adnexa. The lesions are round, whitish-pink, shiny, dome-shaped nodules, 2-3mm in diameter, with an umbilicated center and filled with a cheese-like material. They frequently appear in the margin of the eyelid.

The lesions may be single and unilateral or, as usually seen in patients with HIV, multiple (10-20) and bilateral. When located at the eyelid margin, the lesions shed viral particles into the inferior conjunctival tissues, cul-de-sac and fornix. This produces a symptomatic follicular conjunctival response, epithelial keratitis, pannus formation and conjunctival scarring. Epiphora secondary to resultant punctal occlusion has also been reported.

Pathophysiology: Molluscum contagiosum lesions are produced by a large DNA poxvirus that is usually transmitted by direct contact in children and by sexual activity in adults. Histopathologically, the lesions demonstrate multiple round or oval eosinophilic and basophilic inclusion bodies. Electron microscopy of these inclusions reveals viral particles. These particles and inclusions produce an invasive acanthosis (diffuse hyperplasia and thickening of the dermis) that causes the surface of the epidermis to slough and form a central cavity, which opens through a pore. Intracyto-plasmic inclusions containing the virons, referred to as molluscum bodies, are round, eosinophilic and found in the lower layers of the epidermis.

Management: Molluscum contagiosum typically resolves spontaneously over 3-12 months. In mildly symptomatic patients, only supportive therapy is necessary. In other cases, a more aggressive approach may be necessary to arrest symptoms, prevent transmission and prevent corneal damage. The treatments include excision and curettage, electrodessication, thermal cautery, chemical cautery with topical 10% potassium hydroxide aqueous solution (bid for 30 days), hyperfocal cryotherapy and topical 1% imiquimod cream.

Clinical Pearls

• Bilateral, multiple, molluscum lesions in immunocompromised patients often produce the fewest symptoms. However, because of their extensive involvement and ability to recur, hyperfocal cryotherapy is often the treatment of choice.
• Molluscum lesions respond to coincidental intravenous administration of highly active anti-retroviral therapy (protease inhibitor plus two reverse-transcriptase inhibitors) over 5­6 months.
• Differential diagnoses include verucca and neoplasms.

Other reports in this section

• Molluscum Contagiosum
• Canaliculitis
• Verruca and Papilloma
• Pediculosis and Pthiriasis