DermNet provides Google Translate, a free machine translation service. Note that this may not provide an exact translation in all languages

Idiopathic eruptive macular hyperpigmentation

Author: Dr Daniel Mazzoni, Junior Medical Officer, Royal Brisbane and Women’s Hospital, Brisbane, QLD, Australia. DermNet NZ Editor in Chief: Adjunct A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand. Copy edited by Gus Mitchell. January 2020.


What is idiopathic eruptive macular hyperpigmentation?

Idiopathic eruptive macular hyperpigmentation is a rare benign pigmentary disorder characterised by asymptomatic hyperpigmented macules with a predilection for the upper body regions [1]. It is classified as a variant of acquired dermal macular hyperpigmentation.

See images of acquired dermal macular hyperpigmentation.

Who gets idiopathic eruptive macular hyperpigmentation?

Idiopathic eruptive macular hyperpigmentation can occur in any age group and affects both sexes. Most reported cases involve children and adolescents [2].

What causes idiopathic eruptive macular hyperpigmentation?

The cause of idiopathic eruptive macular hyperpigmentation is unknown. The hypermelanosis occurs sporadically in the absence of preceding illness, inflammation, sun exposure, or medication [3]. It has not been reported to be familial [4].

Hormones have been hypothesised to play a role in cases that have got worse during pregnancy.

What are the clinical features of idiopathic eruptive macular hyperpigmentation?

Idiopathic eruptive macular hyperpigmentation is characterised by multiple discrete asymptomatic brownish-black small macules or larger patches.

  • The pigmentation is most often located on the face, neck, trunk and proximal extremities. Mucosal surfaces, hair, nails, palms, and soles are not affected.
  • The size of lesions can vary from person to person, but most are less than 10 mm in diameter [1,2].
  • There is no preceding erythema.
  • Pigmentation spontaneously regresses within a few months or years.

Idiopathic eruptive macular hyperpigmentation is not influenced by exposure to ultraviolet (UV) radiation [2]. 

How is idiopathic eruptive macular hyperpigmentation diagnosed?

The diagnosis of idiopathic eruptive macular hyperpigmentation is established by histopathological evaluation of a skin biopsy.

  • There is increased pigmentation of the basal cell layer with papillomatosis in otherwise normal epidermis.
  • Dermal melanophages, pigmentary incontinence and sparse mast cells may be observed [2].

What is the differential diagnosis for idiopathic eruptive macular hyperpigmentation?

Idiopathic eruptive macular hyperpigmentation can be clinically misdiagnosed as one of the following conditions. 

What is the treatment for idiopathic eruptive macular hyperpigmentation?

Treatment of idiopathic eruptive macular hyperpigmentation is not required because lesions are asymptomatic and resolve spontaneously within several months to years. Once cleared, there are no residual changes or scarring [1]. Recurrence has not been reported.

See smartphone apps to check your skin.
[Sponsored content]

 

Related information

 

References

  1. Joshi RS, Rohatgi S. Idiopathic eruptive macular pigmentation: A critical review of published literature and suggestions for revision of criteria for diagnosis. Indian J Dermatol Venereol Leprol 2015; 81: 576–80. PubMed
  2. Jang KA, Choi JH, Sung KS, et al. Idiopathic eruptive macular hyperpigmentation: report of 10 cases. J Am Acad Dermatol 2001; 44: 351–3. PubMed
  3. Komorowska O, Szczerlowska-Dobosz A, Roziewska D, et al. Idiopathic eruptive macular hyperpigmentation: A rare pigmentary disorder. Adv Dermatol Allergol 2011; 2: 150–3. Journal
  4. De Souza DF, Cunha AC, Pinerio-Maceira J, et al. Idiopathic eruptive macular pigmentation associated with pregnancy. Int J Dermatol 2010; 49: 810–2. PubMed

On DermNet NZ

Books about skin diseases