The Dermatologist’s Board Review - November 2019

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. The special stain in this slide is:

a) Hematoxylin-eosin stain

b) Silver methenamine (black)

c) Ziehl-Neelsen (acid fast)

d) Fontana (melanin)

e) Periodic acid-Schiff

2. The most likely result of this procedure is a:

a) Small focus of persistent onycholysis

b) Pterygium

c) Split nail plate

d) Focus of leukonychia

e) Longitudinal groove in the nail plate

1. The special stain in this slide is:

e) Periodic acid-Schiff

The hyphae in this nail biopsy of onychomycosis are highlighted by a positive periodic acid-Schiff stain. Silver methenamine may also be used for this purpose, but it does not tint the organism red. Hematoxylin-eosin is the routine stain used for skin biopsies but may not show the organism clearly. The Fontana stain is for melanin and Ziehl-Neelsen is for acid-fast organisms.

References

Mayer E, Izhak OB, Bergman R. Histopathological periodic acid-Schiff stains of nail clippings as a second-line diagnostic tool in onychomycosis. Am J Dermatolopathol. 2012;34(3):270-273. doi:10.1097/DAD.0b013e318234cc49

Barak O, Asarch A, Horn T. PAS is optimal for diagnosing onychomycosis. J Cutan Pathol. 2010;37(10):1038-1040. doi:10.1111/j.1600-0560.2010.01545.x

Wilsmann-Theis D, Sareika F, Bieber T, Schmid-Wendtner MH, Wenzel J. New reasons for histopathological nail-clipping examination in the diagnosis of onychomycosis.
J Eur Acad Dermatol Venereol. 2010;25(2):235-237. doi:10.1111/j.1468-3083.2010.03704.x

2. The most likely result of this procedure is a:

e) Small focus of persistent onycholysis

The procedure being performed here is a 3-mm punch biopsy of the nail bed. The nail matrix, not the nail bed, produces the nail plate. All of the defects mentioned above derive from the nail matrix except onycholysis, which is the only sequela to anticipate.  

Reference

Jellinek N. Nail surgery: practical tips and treatment options. Dermatol Ther. 2007;20(1):68-74. doi:10.1111/j.1529-8019.2007.00113.x

Dr McMichael is professor and chair in the department of dermatology at Wake Forest Baptist Health in Winston-Salem, NC, and a member of the editorial advisory board for The Dermatologist.

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. The special stain in this slide is:

a) Hematoxylin-eosin stain

b) Silver methenamine (black)

c) Ziehl-Neelsen (acid fast)

d) Fontana (melanin)

e) Periodic acid-Schiff

2. The most likely result of this procedure is a:

a) Small focus of persistent onycholysis

b) Pterygium

c) Split nail plate

d) Focus of leukonychia

e) Longitudinal groove in the nail plate

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. The special stain in this slide is:

a) Hematoxylin-eosin stain

b) Silver methenamine (black)

c) Ziehl-Neelsen (acid fast)

d) Fontana (melanin)

e) Periodic acid-Schiff

2. The most likely result of this procedure is a:

a) Small focus of persistent onycholysis

b) Pterygium

c) Split nail plate

d) Focus of leukonychia

e) Longitudinal groove in the nail plate

1. The special stain in this slide is:

e) Periodic acid-Schiff

The hyphae in this nail biopsy of onychomycosis are highlighted by a positive periodic acid-Schiff stain. Silver methenamine may also be used for this purpose, but it does not tint the organism red. Hematoxylin-eosin is the routine stain used for skin biopsies but may not show the organism clearly. The Fontana stain is for melanin and Ziehl-Neelsen is for acid-fast organisms.

References

Mayer E, Izhak OB, Bergman R. Histopathological periodic acid-Schiff stains of nail clippings as a second-line diagnostic tool in onychomycosis. Am J Dermatolopathol. 2012;34(3):270-273. doi:10.1097/DAD.0b013e318234cc49

Barak O, Asarch A, Horn T. PAS is optimal for diagnosing onychomycosis. J Cutan Pathol. 2010;37(10):1038-1040. doi:10.1111/j.1600-0560.2010.01545.x

Wilsmann-Theis D, Sareika F, Bieber T, Schmid-Wendtner MH, Wenzel J. New reasons for histopathological nail-clipping examination in the diagnosis of onychomycosis.
J Eur Acad Dermatol Venereol. 2010;25(2):235-237. doi:10.1111/j.1468-3083.2010.03704.x

2. The most likely result of this procedure is a:

e) Small focus of persistent onycholysis

The procedure being performed here is a 3-mm punch biopsy of the nail bed. The nail matrix, not the nail bed, produces the nail plate. All of the defects mentioned above derive from the nail matrix except onycholysis, which is the only sequela to anticipate.  

Reference

Jellinek N. Nail surgery: practical tips and treatment options. Dermatol Ther. 2007;20(1):68-74. doi:10.1111/j.1529-8019.2007.00113.x

Dr McMichael is professor and chair in the department of dermatology at Wake Forest Baptist Health in Winston-Salem, NC, and a member of the editorial advisory board for The Dermatologist.

1. The special stain in this slide is:

e) Periodic acid-Schiff

The hyphae in this nail biopsy of onychomycosis are highlighted by a positive periodic acid-Schiff stain. Silver methenamine may also be used for this purpose, but it does not tint the organism red. Hematoxylin-eosin is the routine stain used for skin biopsies but may not show the organism clearly. The Fontana stain is for melanin and Ziehl-Neelsen is for acid-fast organisms.

References

Mayer E, Izhak OB, Bergman R. Histopathological periodic acid-Schiff stains of nail clippings as a second-line diagnostic tool in onychomycosis. Am J Dermatolopathol. 2012;34(3):270-273. doi:10.1097/DAD.0b013e318234cc49

Barak O, Asarch A, Horn T. PAS is optimal for diagnosing onychomycosis. J Cutan Pathol. 2010;37(10):1038-1040. doi:10.1111/j.1600-0560.2010.01545.x

Wilsmann-Theis D, Sareika F, Bieber T, Schmid-Wendtner MH, Wenzel J. New reasons for histopathological nail-clipping examination in the diagnosis of onychomycosis.
J Eur Acad Dermatol Venereol. 2010;25(2):235-237. doi:10.1111/j.1468-3083.2010.03704.x

2. The most likely result of this procedure is a:

e) Small focus of persistent onycholysis

The procedure being performed here is a 3-mm punch biopsy of the nail bed. The nail matrix, not the nail bed, produces the nail plate. All of the defects mentioned above derive from the nail matrix except onycholysis, which is the only sequela to anticipate.  

Reference

Jellinek N. Nail surgery: practical tips and treatment options. Dermatol Ther. 2007;20(1):68-74. doi:10.1111/j.1529-8019.2007.00113.x

Dr McMichael is professor and chair in the department of dermatology at Wake Forest Baptist Health in Winston-Salem, NC, and a member of the editorial advisory board for The Dermatologist.