Squamous cell carcinoma of the nail bed: is finger predominance another clue to etiology? A report of 5 cases.

Although squamous cell carcinoma (SCC) is commonly found on sun-exposed skin, the occurrence of this malignancy in the nail bed is rare. We report 5 cases of SCC of the nail bed and suggest that the disproportionate number of neoplasms of this type on the second, third, and fourth fingers, combined with the known relationship of SCC and human papillomavirus (HPV), is evidence that most SCC of the nail bed result from contact with HPV. Moreover, we suggest that patients who present with new, verrucous lesions of the nail bed and have a history of cervical dysplasia, cervical carcinoma, or condyloma acuminata undergo diagnostic biopsy as opposed to traditional destructive therapy for a lesion presumed benign.

Routine periodic acid-Schiff staining of nail plate fragments in fungal cultures for onychomycosis: a method to increase the sensitivity of diagnosis.

We propose the routine staining of nail plate fragments with periodic acid-Schiff stain to increase diagnostic accuracy in diagnosing onychomycosis. The advantages of this method, including increasing diagnostic yield after contaminant growth, confirmation of negative culture, and low cost, are reviewed.

A review of topical and intralesional cidofovir.

Cidofovir is a potent nucleoside analog antiviral drug approved for the treatment of cytomegalovirus (CMV) retinitis in patients with the Acquired Immune Deficiency Syndrome (AIDS). It is currently available only for intravenous infusion. Several small studies and case reports describe the successful use of cidofovir applied either topically or by intralesional injection in several virally induced cutaneous diseases. Available information demonstrates that cidofovir is a potent antiviral agent with activity against several DNA viruses that cause cutaneous disease when applied topically or administered by intralesional injection. No significant systemic side effects have been noted, although application site reactions are common and can occasionally be severe. The effective use of topical and intralesional cidofovir for the treatment of diseases of the skin caused by DNA viruses has been demonstrated in animals and a limited number of patients including those infected with human immunodeficiency virus (HIV). This article reviews the pharmacology of cidofovir and the utility of topical and intralesional cidofovir for the treatment of viral infections caused by human papillomavirus, herpesviruses (including acyclovir resistant strains), Kaposi's sarcoma-associated herpesvirus, molluscum contagiosum and monkeypox.

A potpourri of parasitic infestations.

Ectoparasitic infestations are common cutaneous problems. The vast majority of these are attributable to scabies and pediculosis. While these are usually readily recognizable, infestations caused by other ectoparasites, such as nonscabetic mites, may pose difficulty in diagnosis. In this article, we present a variety of ectoparasitic infestations that initially eluded diagnosis and review the gamut of ectoparasites that can cause eruptions in the skin.

Hereditary hypodontia and onychorrhexis of the fingernails and toenail koilonychia: Witkop's tooth-and nail syndrome.

The tooth-and-nail syndrome (Witkop's syndrome) is a rare autosomal dominant ectodermal dysplasia manifest by defects of the nail plates of the fingers and toes and hypodontia with normal hair and sweat gland function. We report a thirteen year-old girl who presented with marked longitudinal ridging of the nail plates of all ten fingers. The toenails were mildly ridged with koilonychia. Her mother's fingers were similarly affected to a lesser degree while her toenails appeared normal. Examination of the child's dentition revealed a hyperplastic frenulum and the absence of one of the usual four mandibular incisors. History provided by the mother described the maternal grandmother and maternal great aunt as having identical nail findings and the presence of only three lower incisors. Hair examination was normal in the mother and child, and no history or findings of sweat gland dysfunction was present. This report describes familial hypodontia, fingernail onychorrhexis, and toenail koilonychia consistent with Witkop's syndrome.

Topical and intralesional cidofovir: a review of pharmacology and therapeutic effects.

BACKGROUND: Cidofovir is a potent nucleoside analog antiviral drug approved for the treatment of cytomegalovirus (CMV) retinitis in patients with AIDS. It is currently available only for intravenous infusion. Several small studies and case reports describe the successful use of cidofovir applied either topically or intralesionally in several virally induced cutaneous diseases. OBJECTIVE: Our purpose was to review the usefulness of topical and intralesional cidofovir for the treatment of viral infections caused by human papillomavirus, herpesviruses (including acyclovir-resistant strains), Kaposi's sarcoma-associated herpesvirus, and molluscum contagiosum. METHODS: We performed a review of recent literature. RESULTS: Cidofovir is a potent topical intralesional antiviral agent with activity against several DNA viruses that cause cutaneous disease. No significant systemic side effects have been noted, although application site reactions are common and can occasionally be severe. CONCLUSION: The effective use of topical and intralesional cidofovir for the treatment of diseases of the skin caused by DNA viruses has been demonstrated in a limited number of patients including those infected with HIV. Although larger studies will be necessary to determine the specific function that topical cidofovir will have in the treatment of cutaneous diseases caused by DNA viruses, the drug offers significant promise.