ABSTRACT

Molluscum contagiosum (MC) is a viral infection of the skin and mucosal tissues characterized by skin-colored or transparent round nodules with a dimple or pit in the center. The infection is caused by a DNA poxvirus called the MC virus. Although MC generally occurs in children, it has also been reported in immunocompromised and atopic patients. The virus is transmitted by skin contact or sexual intercourse. The lesions disappear spontaneously within several months in most cases. However, excision, cryotherapy, cauterization, topical chemical and antiviral agents, and/or oral cimetidine are used in refractory cases or to accelerate the healing process. Herein, we discussed the clinical findings and our treatment of two patients with unilateral chronic conjunctivitis associated with eyelid MC lesions in light of the literature.

Introduction

Molluscum contagiosum (MC) is characterized by papular lesions in the skin and mucous membranes caused by theMolluscum contagiosumvirus, a DNA virus from the poxvirus group.^1,2Humans are the only known host. The virus is transmitted through skin contact and sexual intercourse. It is particularly common in hot, developing countries and in communities with poor personal hygiene.^1,2,3,4Signs of MC infection have been reported in about 4.5% of children under 10 years old. In developed countries, infections are sometimes acquired from swimming pools, saunas, and sports centers. In addition, it can also be seen in immunosuppressed patients (e.g. with AIDS or using drugs such as corticosteroids, TNF-α antibodies, and methotrexate), and in patients with atopic dermatitis, sarcoidosis, and Wiskott-Aldrich syndrome.^5,6,7,8Diagnosis is usually based on clinical findings, and histopathological examination and laboratory tests are often not necessary.

The lesions, located on the skin and mucosa, typically appear as small (between about 2-6 mm), raised, flesh-colored or clear papules and there is pearly white caseous material in the pitted center.^1,2,3,9The papular lesions, usually found in clusters, are often seen on the face, head, torso, and extremities in children, and in the genital area, lower abdomen, and upper legs in young adults in whom the infection is sexually transmitted.

Ophthalmic MC lesions are often located on the eyelids.^1,2,8,9,10Viral proteins shed from the lid lesions into the tear film can lead to a hypersensitivity reaction with secondary chronic follicular reaction, punctate keratopathy in the conjunctiva, and in some cases subepithelial opacities and pannus. Rarely, primary MC lesions are seen in the conjunctiva and cornea. While the lesions usually resolve spontaneously within a few months, treatments such as excision, incision and curettage, cryotherapy, cauterization, topical chemical agents, and oral cimetidine can be used in refractory cases and to speed up the healing process.^{1,11,12,13,14}

In this case report, the clinical findings and treatment of two patients who were admitted with unilateral chronic conjunctivitis and were found to have eyelid MC lesions are discussed in light of the literature.

Discussion

Ocular involvement of MC presents with round, small, hard papules on the eyelids. The virus proliferates in epithelial cells. After the lesions reach about 3-5 mm in diameter, a central depression forms due to the cellular damage mechanism and they typically develop the appearance of whitish lesions filled with caseous material and having a dimple or pit in the center.^1,2

Although the diagnosis is made clinically when these characteristic MC lesions are evident on the lids, half of patients cannot be diagnosed at the first examination. Both of our patients presented with a 2- to 3-month history of red eye and lid edema. The first case had previously seen several ophthalmologists, but the lid lesions were overlooked and her condition had been treated as infectious conjunctivitis. Charteris et al.²examined the clinical and immunopathologic features of 35 MC cases and found that only 60% of the patients were diagnosed at the time of initial presentation. Histopathologic sections showed increased numbers of T lymphocyte cells and macrophages in the epidermis and dermis around the molluscum lesion.

In recent years, the increased incidence of MC among adults has been associated with AIDS.^1,2,5,6HIV-related lesions are usually numerous and at least 5 mm in size. They respond poorly to treatment and recurrence is common. Blood testing of our patients revealed no significant systemic pathology or immunodeficiency.

The differential diagnosis of lid lesions can include basal cell carcinoma, papilloma, chalazion, sebaceous cyst, keratoacanthoma, blepharitis, wart, eczema, obstructed nasolacrimal duct, and ectropion. However, the typical appearance of papular lesions is consistent with MC. Allergic, bacterial, viral, and chlamydial conjunctivitis may be considered in the differential diagnosis of the follicular reaction in patients with conjunctival involvement. For patients with corneal pannus, it may be necessary to rule out chlamydia and rosacea keratitis in the differential diagnosis.

Chlamydial conjunctivitis is defined as inclusion conjunctivitis occurring in adulthood. Ocular involvement may occur in 0.3-2% of patients with urogenital manifestation.¹⁵Ocular findings emerge within 5-14 days after contagion. Follicular response appears in the lower fornix and palpebral conjunctiva. In chlamydial infection, history and clinical findings facilitate diagnosis, and treatment is systemic.¹⁵

Although MC resolves spontaneously within months in healthy, immunocompetent individuals, it requires treatment in refractory cases.¹ It should be kept in mind that progressive corneal neovascularization and scarring may develop, especially in patients with chronic conjunctivitis and corneal involvement. Conjunctivitis and keratitis show rapid improvement after skin lesions are eradicated. There is no known antiviral treatment specific for MC. While topical ganciclovir is approved for use in acute herpetic keratitis, its efficacy has also been demonstrated against cytomegalovirus and some strains of adenovirus, while systemic administration of ganciclovir is effective against HIV.¹⁶Although there are no previous studies showing that topical ganciclovir is effective against MC, we initially administered it to both of our patients considering its broad-spectrum antiviral activity, but no improvement was achieved.

Surgical techniques include cryotherapy with liquid nitrogen, cauterization, needle aspiration, photodynamic therapy, and various laser therapies.^{1,11,12,13,14}Silver nitrate, phenol, and trichloracetic acid are used as chemical agents, while treatment options for immunocompromised patients with refractory lesions include topical cidofovir (5%), intralesional or systemic interferon, imiquimod cream (5%), salicylic acid, glycolic acid, tretinoin, tazarotene, 5% sodium nitrate, podophyllotoxin, liquefied phenol, cantharidin, potassium hydroxide, 1% adenine cream, and oral cimetidine. Eyelid scarring, depigmentation, and eyelash loss may occur after these treatments. Karabulut et al.¹¹reported dramatic improvement in dense eyelid lesions with only physical drainage in an immunocompetent pediatric patient with MC. Weller et al.¹⁴compared esthetic appearance after chemical ablation with phenol versus emptying the lesion by squeezing and reported that although there was no significant difference, phenol treatment caused more scarring. In our cases, we demonstrate that surgical excision of the papules and cryotherapy applied to their bases and margins resulted in complete disappearance of the lesions with no scarring or recurrences within the 6-month follow-up period, and the chronic conjunctivitis also resolved completely.