A 63-year-old woman reports changes in her toenails. The toenails of her right foot have been discolored for 3 years and are becoming thicker and more difficult to cut. She experiences pain in her toenails when wearing some of her high-heeled shoes. The patient feels that her toenails are "embarrassing" when she is barefoot at the beach.
A photograph of her foot is shown below.

A KOH preparation of material removed from under the nails reveals hyphae.
What is the best therapy for this patient?

Question

A 63-year-old woman reports changes in her toenails.  The toenails of her right foot have been discolored for 3 years and are becoming thicker and more difficult to cut.  She experiences pain in her toenails when wearing some of her high-heeled shoes.  The patient feels that her toenails are "embarrassing" when she is barefoot at the beach.
A photograph of her foot is shown below.

A KOH preparation of material removed from under the nails reveals hyphae.
What is the best therapy for this patient?

Quizplus · Accepted Answer

11ec193a_9778_b38e_853d_df92e0cd14ed_MD0002_00 The yellowish discoloration of the toenails and hyphae on KOH smear make onychomycosis the most likely diagnosis. Nail dystrophy from psoriasis has a similar look, and the diagnosis should be established with KOH preparation. If KOH is negative, culture of the nail material on special media should be performed. Culture, which can take up to 6 weeks for an organism to grow, is the gold standard for establishing the diagnosis. Treatment of onychomycosis is expensive and often ineffective, with a high (20-50%) recurrence rate. Adverse reactions to systemically administered drugs occur in 2-4% of patients. Thus, treatment is indicated when it becomes necessary (Table). Most studies indicate that a 12-week course of oral terbinafine offers the best chance (40%-60%) of successful treatment and has fewer drug-drug interactions. One week of twice-daily itraconazole per month for 2 months (pulse therapy) is another option for onychomycosis (Choice D). Even though its efficacy is less than that of daily terbinafine, it can still be used as an alternative for those who are not drug compliant or prefer this method. Although debatable, most clinicians obtain pretreatment serum aminotransferase as both terbinafine and the azoles can be associated with hepatotoxicity. (Choice E) Topical anti-fungal agents are generally ineffective due to poor penetration of the drug into the nail plate. (Choices A and C) Multiple studies have shown that griseofulvin and fluconazole are less effective than terbinafine or itraconazole for onychomycosis. Educational objective: Because nail dystrophies caused by other diseases (eg, psoriasis, lichen planus) can mimic the appearance of onychomycosis, confirmation with potassium hydroxide (KOH) preparation or culture of nail scrapings is recommended. If therapy is undertaken for toenail fungal disease, optimal results are obtained with 3 months of oral terbinafine. __________ References: Cumulative meta-analysis of systemic antifungal agents for the treatment of onychomycosis. (http://www.ncbi.nlm.nih.gov/pubmed/15030339)

A 63-Year-Old Woman Reports Changes in Her Toenails