Peer Reviewed

Dermclinic

What Is the Best Approach to This Subungual Lesion?

David L. Kaplan, MD
Volume 56 - Issue 12 - December 2016

AUTHOR:
David L. Kaplan, MD—Series Editor

CITATION:
Kaplan DL. What is the best approach to this subungual lesion? Consultant. 2016;56(12):1108-1109.

 

This 59-year-old woman presented for evaluation of a new area of pigmentation under her great toenail that she had noticed for the first time in the past 2 weeks. It was asymptomatic, and there was no history of trauma. No other toenails have a similar appearance.

subungual leasion

What is the best approach to this subungual lesion?

  1. Punch biopsy through the nail plate
  2. Excisional biopsy by removing the nail plate and excising the pigmented lesion beneath
  3. Conservative management with reevaluation over the next 2 to 3 months
  4. Clip the nail back as far as possible to expose the lesion
  5. Offer reassurance only

What is the most likely diagnosis?

  1. Benign melanocytic nevus
  2. Melanoma
  3. Longitudinal pigmented band (melanonychia striata)
  4. Onychomycosis
  5. Subungual hematoma

Answers and discussion on next page.

Answer: Punch biopsy of a subungual hematoma

This patient had 2 subungual hematomas. Upon further history, she said that the dark areas under her toenail had appeared after she had taken a long walk. The clinical clue to the diagnosis was the longitudinal streaking and sudden onset, although these lesions are hard to discern. Doing a punch biopsy through the nail plate, taking care not to go too deep, will provide the answer when in doubt. It has been recently reported that using a fecal occult blood test to identify the heme is an easy and effective way to establish the diagnosis of subungual hematoma.1 

David L. Kaplan, MD, is a clinical assistant professor of dermatology at the University of Missouri–Kansas City School of Medicine in Kansas City, Missouri, and at the University of Kansas School of Medicine in Kansas City, Kansas. He practices adult and pediatric dermatology in Overland Park, Kansas.

Reference:

1. Lee A, Kovich O, Greenspan A, Shan HY. Rapid, cost-effective diagnosis of subungual hematoma. DermPearls. http://dermpearls.com/2011/01/rapid-cost-effective-diagnosis-of-subungual-hematoma. Published January 10, 2011. Accessed November 23, 2016.