Confluent and reticulated papillomatosis

Author: Vanessa Ngan, Staff Writer, 2005. Updated by A/Prof Amanda Oakley, December 2017.

What is confluent and reticulated papillomatosis?

CRP is a rare skin disease characterised by a network pattern of discoloured small flat plaques. It mainly affects the mid trunk of young adults.

Confluent and reticulated papillomatosis is also known as Gougerot-Carteaud Syndrome. Gourgerot and Carteaud originally described the condition in 1927.

Confluent and reticulated papillomatosis

Who gets confluent and reticulated papillomatosis

Confluent and reticulated papillomatosis is more common in young women than in men (except in Japan where the reverse is true) and usually starts soon after puberty

What is the cause of confluent and reticulated papillomatosis?

The cause of confluent and reticulated papillomatosis is unknown. Several possible causes have been suggested and include:

  • Hormonal disturbance – it has been associated with hormonal abnormalities such as diabetes mellitus, thyroid disease and obesity
  • Proliferation of keratinocytes — microscopic studies show increased turnover of cells and increased production of the skin protein, keratin.
  • Bacterial infection – an actinomycete called Dietzia was isolated from a patient with confluent and reticulated papillomatosis [1].
  • Hereditary factors – there are several reports of CRP occurring in more than one family member. Keratin-16 may be involved.

It is no longer thought to be due to yeast infection (Malassezia).  

What are the clinical features of confluent and reticulated papillomatosis?

Confluent and reticulated papillomatosis causes no symptoms.  

  • There are greyish blue-brown 1-5mm flat scaly, wart-like bumps.
  • Papules may become confluent, larger patches with a net-like pattern on the edges.
  • Lesions usually first appear between the breasts and in the midline of the back, and gradually spread over the breasts, to include the neck, armpits and abdomen. They may spread across the shoulders, into the pubic areas and onto the face.

Confluent and reticulated papillomatosis is chronic and persistent or may have exacerbations and remissions.  

What is the differential diagnosis of confluent and reticulated papillomatosis?

Other conditions that may be considered include pityriasis versicolor, acanthosis nigricans, Dowling-Degos diseasedyskeratosis congenita, prurigo pigmentosa, terra firma-forme dermatosis, and Darier disease.

How is confluent and reticulated papillomatosis diagnosed?

Confluent and reticulated papillomatosis is usually diagnosed by its clinical features.

  • Reticulated macules, papules and plaques
  • Location on upper trunk, neck, and/or flexures
  • Absence of yeasts on microscopy  
  • Improvement with antibiotics

Histopathology of a skin biopsy shows patchy hyperkeratosis, papillomatosis, acanthosis and increased pigmentation.

What is the treatment for confluent and reticulated papillomatosis?

Confluent and reticulated papillomatosis is a benign skin disorder that results in cosmetic disfigurement.  Weight loss has been advocated in those that are overweight.

Antimicrobial agents

Topical antiproliferative agents

Discontinuation of successful treatment may result in a recurrence of the condition.


Related Information


  • Natarajan S, Milne D, Jones AL, Goodfellow M, Perry J, Koerner RJ. Dietzia strain xL a newly described Actinomycete isolated from confluent and reticulated papillomatosis. British Journal of Dermatology 2005; 153: 825-827
  • Confluent and reticulated papillomatosis: diagnostic and treatment challenges., Lim JH,Tey HL,Chong WS,, Clinical, cosmetic and investigational dermatology, 2016. PubMed.

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