A 42-year-old woman comes to the office due to worsening toenail disfiguration over the past 3 months. The patient has had no lower extremity pain or redness and recalls no trauma. She has a history of hypertension and takes hydrochlorothiazide.
Examination findings are shown in the image.

Which of the following is the best next step in management of this patient?

Question

A 42-year-old woman comes to the office due to worsening toenail disfiguration over the past 3 months.  The patient has had no lower extremity pain or redness and recalls no trauma.  She has a history of hypertension and takes hydrochlorothiazide.
Examination findings are shown in the image.

Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

This patient may have onychomycosis, which is caused by a variety of fungi, including yeasts, dermatophytes, and other molds. Typical findings include discoloration (white, yellow, brown), dystrophic changes (eg, thickening, splitting, fracturing), and occasionally injury to the underlying nail bed. However, only 50%-60% of patients with dystrophic nails have onychomycosis. Other conditions that can cause a similar appearance include psoriasis, eczema, and lichen planus. Given this, many experts recommend confirmation of onychomycosis before starting antifungal treatment. Potassium hydroxide (KOH) preparation of nail scrapings is simple and inexpensive, and fungal culture or histopathological examination of nail clippings can also be considered. As an alternate strategy, empiric oral terbinafine may be cost effective for toenail onychomycosis, with diagnostic testing reserved for those who fail treatment. However, topical antifungal therapy (eg, efinconazole) is less effective and is typically recommended for less severe cases (eg, limited to distal nail plate) and only after diagnostic confirmation (Choice D). (Choice A) Biopsy is typically employed when malignancy (eg, squamous cell carcinoma) is suspected or the diagnosis is uncertain. Nail biopsy can confirm the diagnosis of onychomycosis, but less disruptive sampling methods (eg, nail scrapings) are typically adequate for diagnosis. (Choice C) Topical antibiotics and antiseptic soaks are useful in treating acute paronychia, which presents with swelling, erythema, and pain involving the nail folds and surrounding skin. (Choice E) Topical corticosteroids are used for chronic paronychia (eg, swelling and redness of the nail folds with dystrophic changes of the nail plate) and ungual psoriasis (eg, nail pitting and onycholysis). Corticosteroids are not indicated for onychomycosis. Educational objective: Onychomycosis can be difficult to distinguish from other nail dystrophies (eg, psoriasis, eczema, lichen planus). Potassium hydroxide (KOH) preparation of nail scrapings can confirm the diagnosis prior to initiation of oral antifungal therapy. __________ References: Onychomycosis: diagnosis and management. (http://www.ncbi.nlm.nih.gov/pubmed/22016272) Cost-effectiveness of confirmatory testing before treatment of onychomycosis. (http://www.ncbi.nlm.nih.gov/pubmed/26716567)

A 42-Year-Old Woman Comes to the Office Due to Worsening