Dermatology: Practical and Conceptual


Letter  |  Dermatol Pract Concept 2020;10(2):e2020041 1

Dermatology Practical & Conceptual

Introduction

Sudden change in a pigmented lesion accompanied by the 

appearance of new lesions is a cause for concern for poten-

tial melanoma development. Here we present such a case, 

diagnosed as eruptive blue nevi in a young woman. This case 

highlights the importance of dermoscopy for the diagnosis of 

this rare phenomenon.

Case Presentation

A 24-year-old woman with no significant medical history 

presented with a blue lesion on her right shin. The patient 

reported that the lesion had been present on her leg for many 

years but had started growing in the preceding 2 months. In 

addition, she had noticed 2 additional similar, albeit smaller, 

blue lesions that had appeared on her right thigh and her 

buttocks 2 weeks before. The lesions were asymptomatic, 

and the patient denied any additional complaints at the time 

of examination.

Clinical examination revealed a well-circumscribed, 6 mm 

in diameter, blue-gray nodule on the distal lateral aspect of 

the right shin (Figure 1A). Smaller macules, 4 mm in diameter, 

with a lighter blue color, were present on her right thigh and 

buttocks (Figure 1B). Dermoscopic examination revealed 

structureless, blue, symmetrical lesions, with a homogenous 

pattern (Figure 2). Histopathological examination confirmed 

the clinical suspicion of a cellular blue nevus, with a Ki-67 

proliferation index of less than 1%, and negative HMB45 

and MART-1 stainings.

Conclusions

Blue nevus is a benign neoplasm composed of aberrant mela-

nocytes located in the dermis, which can be found in 0.5%-

4% of the white population. It is usually acquired during the 

second decade of life, presenting as a macule, papule, nodule, 

or plaque on the buttocks, face, scalp, hands, or feet. Several 

types of blue nevi exist, including common, cellular, or com-

bined blue nevus; atypical or malignant blue nevus; and large 

patch/plaque lesions [1].

When a blue nevus develops, it usually remains stable 

and does not change with time. Furthermore, the presence of 

multiple blue nevi is a rare phenomenon and usually presents 

as aggregated or plaque-type lesions. So far, there have been 

only 13 reports of eruptive blue nevi, where the number of 

Eruptive Blue Nevi: A Rare Phenomenon Diagnosed 
With the Aid of Dermoscopy

Laurent Klapholz,1 Yuval Ramot1

1 Department of Dermatology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel

Key words: blue nevus, melanoma, dermoscopy, dermatology, skin

Citation: Klapholz L, Ramot Y. Eruptive blue nevi: a rare phenomenon diagnosed with the aid of dermoscopy. Dermatol Pract Concept. 
2020;10(2):e2020041. DOI: https://doi.org/10.5826/dpc.1002a41

Accepted: December 4, 2019; Published: April 3, 2020

Copyright: ©2020 Klapholz and Ramot. This is an open-access article distributed under the terms of the Creative Commons Attribution 
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are 
credited.

Funding: None.

Competing interests: The authors have no conflicts of interest to disclose.

Authorship: Both authors have contributed significantly to this publication.

Corresponding author: Yuval Ramot, Department of Dermatology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty 
of Medicine, Jerusalem, 9112001, Israel. Email: yramot@gmail.com

https://doi.org/10.5826/dpc.1002a41
mailto:yramot@gmail.com


2 Letter  |  Dermatol Pract Concept 2020;10(2):e2020041

2. Kesty K, Zargari O. Eruptive blue nevi. 

Indian J Dermatol Venereol Leprol. 

2015;81(2):198-201.

K, eds. Fitzpatrick’s Dermatology in Gen-

eral Medicine. 8th ed. New York: Mc-

Graw-Hill; 2012.

nevi varied from 3 to hundreds [2]. In 

general, but also in the case of eruptive 

blue nevi, the sudden eruption of mul-

tiple nevi is observed following physio-

logical conditions such as pregnancy or 

pathological disorders such as sunburn 

or trauma.

Although the clinical and dermo-

scopic features of the lesions in the 

patient described here were typical for 

a blue nevus, the sudden change and 

the appearance of new lesions in a short 

period of time were suspicious, espe-

cially when considering the importance 

of the blue hue as part of the dermo-

scopic features of malignancy. This, 

together with the lack of any trigger-

ing factor, warranted histopathological 

examination of the lesion to rule out 

malignancy.

Here we presented a rare case of 

eruptive blue nevi in a patient with 

no known triggering factors. It high-

lights the need for careful inspection of 

these lesions to rule out melanoma or 

malignant blue nevus, especially since 

melanoma has been reported to mimic 

benign blue nevus.

References

1. Grichnik JM, Rhodes AR, Sober AJ. 

Benign neoplasias and hyperplasias of 

melanocytes. In: Goldsmith LA, Katz SI, 

Gilchrest BA, Paller AS, Leffell DJ, Wolff 

Figure 1. (A) A well-circumscribed, blue-gray macule on the distal lateral aspect of the right 

shin. (B) A smaller blue lesion on the right thigh.

Figure 2. Dermoscopic examination of the lesions on the shin (A) and thigh (B) showing 

structureless, blue, symmetrical lesions, with a homogenous pattern.