Dermatology: Practical and Conceptual


Image Letter | Dermatol Pract Concept. 2025;15(2):4997 1

Dermoscopy of a Rare Case of Porokeratotic 
Eccrine Ostial and Dermal Duct Nevus

Ranjana Beniwal1, Akriti Agrawal2

1 Dr. Sampurnanand Medical College and associated group of hospitals, Jodhpur

2 Department of Dermatology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry

Citation: Beniwal R, Agrawal A. Dermoscopy of a Rare Case of Porokeratotic Eccrine Ostial and Dermal Duct Nevus.  
Dermatol Pract Concept. 2025;15(2):4997. DOI: https://doi.org/10.5826/dpc.1502a4997 

Accepted: February 4, 2025; Published: April 2025

Copyright: ©2025 Beniwal et al. This is an open-access article distributed under the terms of the Creative Commons Attribution-
NonCommercial License (BY-NC-4.0), https://creativecommons.org/licenses/by-nc/4.0/, which permits unrestricted noncommercial use, 
distribution, and reproduction in any medium, provided the original authors and source are credited.

Funding: None.

Competing Interests: None.

Authorship: All authors have contributed significantly to this publication. 

Corresponding Author: Ranjana Beniwal M.D, Consultant dermatologist, Department of Dermatology, Venereology and Leprology,  
Dr. Sampurnanand Medical College and associated group of hospitals, Jodhpur; ORCID ID 0000-0002-9358-8282.  
E-mail: ranjanabeniwal@gmail.com 

Case Presentation

A 20-year-old female presented with multiple asymptomatic 

raised lesions over the right hand since birth. Family history 

was unremarkable. Systemic examination was within normal 

limits. Examination revealed multiple discrete firm pitted 

papules with a central comedo-like keratotic plug arranged in 

a Blaschkoid pattern over the palmar aspect of the middle fin-

ger of her right hand (Figure 1A). Dermoscopy showed mul-

tiple yellowish-white milia-like structures over a background 

of brownish globules (Figure 1B). Histopathology showed 

hyperkeratosis, acanthosis, and papillomatosis. Columns of 

parakeratosis were seen invaginating the epidermis with an 

absent granular layer beneath the columns (Figure 1C). Based 

on these findings, a diagnosis of porokeratotic eccrine ostial 

and dermal duct nevus (PEODDN) was made. The patient 

was started on oral isotretinoin 20 mg daily and 12% sali-

cylic acid ointment for six weeks, with satisfactory subjective 

response and 20–25% objective improvement. (Figure 1D)

Teaching Point

Porokeratotic eccrine ostial and dermal duct nevus is a rare 

disorder considered to be an eccrine hamartoma. Most of 

the cases are present since birth or early childhood, but cases 

with later age at onset have also been reported [1]. Dermos-

copy has been done in only limited cases of PEODDN, and 

features such as numerous distinct white dots that represent 

hypertrophic dilated appendageal ducts are an important di-

agnostic feature of PEODDN, as also seen in our case [2]. 

Dermoscopy and the pathognomonic histopathological find-

ing of a parakeratotic column overlying eccrine duct helps 

in differentiating PEODDN from other close differentials 

such as linear verrucous epidermal naevus and unilateral 

punctate porokeratosis. Different modalities have been tried 

for the management of PEODDN including topical steroids, 

cryotherapy, retinoids, and ablative lasers with variable 

 efficacy [1]. 



2 Image Letter | Dermatol Pract Concept. 2025;15(2):4997

Figure 1. (A) Multiple papules with central keratotic plug arranged in a Blaschkoid pattern over palmar aspect of middle finger of right hand. 

(B) Dermoscopy showing multiple yellowish-white milia-like structures over a background of brownish globules. (C) Histopathology show-

ing columns of parakeratosis are seen invaginating the epidermis with absent granular layer beneath the columns (H&E, ×100). (D) 20–25% 

improvement seen in lesions after six weeks of therapy.

References

1. Masferrer E, Vicente MA, Bassas-Vila J, Rovira C,  

González-Enseñat MA. Porokeratotic eccrine ostial and dermal 

duct naevus: report of 10 cases. J Eur Acad Dermatol Venereol. 

2010 Jul;24(7):847-51. DOI:10.1111/j.1468-3083.2009.03498.x.  

PMID: 19925595.

2. Sarma N, Chakraborty S. Diagnostic role of dermatoscopy in 

porokeratotic adnexal ostial nevus. Indian J Dermatol Venereol 

Leprol. 2019;85(5):546-548. DOI:10.4103/ijdvl.IJDVL_776_18. 

PMID: 31368451.