Which of the following statements regarding onychomycosis is true?
A) The infection is caused by Trichophyton rubrum.
B) Fungi are responsible for 90% of nail dystrophies.
C) Ciclopirox (Penlac) is very effective for the treatment of onychomycosis.
D) Griseofulvin and ketoconazole are first-line medications for the treatment of onychomycosis.
E) Periodic testing of renal function is indicated with the use of antifungal medication.
A) The infection is caused by Trichophyton rubrum.
ans is A
treatment is griseofulvin ( inhibit microtubule formation)
also terbinafine( blocking squalene eposidase of ergosterole)
AAA is correct
Onychomycosis (tinea unguium) is a fungal infection of the nail bed, matrix, or plate. Toenails are affected more often than fingernails. The infection is usually caused by T. rubrum, which invades the nail bed and the underside of the nail plate beginning at the hyponychium and then migrating proximally through the underlying nail matrix. Because fungi are responsible for only approximately one-half of nail dystrophies, the diagnosis of onychomycosis may need to be confirmed by potassium hydroxide preparation, culture, or histology. Psoriasis, lichen planus, contact dermatitis, trauma, nail-bed tumor, and yellow nail syndrome may be mistakenly diagnosed as onychomycosis. The FDA has approved ciclopirox (Penlac) nail lacquer for the treatment of mild to moderate onychomycosis caused by T. rubrum without involvement of the lunula. Although safe and relatively inexpensive, ciclopirox therapy is seldom effective. Triazole and allylamine antifungal drugs have largely replaced griseofulvin and ketoconazole as first-line medications in the treatment of onychomycosis. These agents offer shorter treatment courses, higher cure rates, and fewer relapses. Of the newer drugs, terbinafine (Lamisil), itraconazole (Sporanox), and fluconazole (Diflucan) are the most widely used. Liver enzyme monitoring is recommended before continuous medication therapy is initiated and every 4 to 6 weeks during treatment. Onychomycosis is expensive to treat. Costs include medications, procedures, laboratory tests, and health-care providers' time, as well as expenses associated with the management of adverse drug effects