The contents of these questions are taken from the Galderma Pre-Board Webinar. The Pre-Board Webinar is now an online course. For details, go to https://www.galdermausa.com/Our-Commitment/PreBoard-Webinar.aspx.
1. This 43-year-old stockbroker has been treated by his primary care physician for a clinically diagnosed fungal infection with fluconazole for 6 months. The nails have not changed. Although potassium hydroxide and culture should be done, they will probably be negative. He has:
a) Habit-tic deformity
b) Median nail dystrophy
c) Chronic paronychia
d) Eczema of the proximal nail fold
e) Yellow nail syndrome
2. The finger of this patient shows a severe hypertrophy of the distal nail unit. It is most likely due to:
a) Verrucous squamous cell carcinoma
b) Subungual wart
c) Pachyonychia congenita tarda
d) Pterygium inversum unguis
e) Hypertrophic lichen planus
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1.This 43-year-old stockbroker has been treated by his primary care physician for a clinically diagnosed fungal infection with fluconazole for 6 months. The nails have not changed. Although potassium hydroxide and culture should be done, they will probably be negative. He has:
a) Habit-tic deformity
Habit-tic deformity is characterized by multiple Beau lines of the nail plate, hypertrophied lunula, and absent cuticle. Median nail dystrophy shows a midline nail plate split with a fir tree-like configuration. The lunula is enlarged in both conditions. Chronic paronychia produces multiple Beau lines; however, no paronychia is present here. This is also true of chronic nail fold eczema, which is also absent. In yellow nail syndrome, the cuticles disappear but the nails have a yellow color with increased longitudinal and lateral curvature plus markedly reduced growth rates.
References
Kim BY, Jin SP, Won CH, Cho S. Treatment of median canaliform nail dystrophy with topical 0.1% tacrolimus ointment. J Dermatol. 2010;37(6):573-574. doi:10.1111/j.1346-8138.2009.00769.x
Wu JJ. Habit tic deformity secondary to guitar playing. Dermatol Online J. 2009;15(3):16.
2. The finger of this patient shows a severe hypertrophy of the distal nail unit. It is most likely due to:
d) Pterygium inversum unguis
This entity is a hypertrophy of the distal nail bed/hyponychium due to pterygium inversum unguis. The distal nail plate remains attached on its under surface to the stratum corneum of the distal nail unit, which may result in painful digits and make it difficult to trim the nails without bleeding. It most commonly occurs in patients with collagen vascular disease, but it is also seen in otherwise healthy individuals. It is thought that there is obliteration of the distal nail groove. Treatment has not been highly successful and sometimes surgery may be helpful. The other choices do not fit: lesion is not verrucous, nail is not thickened, and lichen planus is usually destructive/atrophic. n
Reference
Balma A, Pope E. Acquired idiopathic pterygium inversum unguis. Clin Pediatr (Phila). 2010;49(4):394-395. doi:10.1177/0009922809346731
Dr McMichael is professor and chair in the department of dermatology at Wake Forest Baptist Health in Winston-Salem, NC.
