Crutchfield Dermatology Case-of-the-month header image

Case of the Month

A 19-year-old man comes in for the treatment of “body fungus”. He said he had done 3 sessions of Selsun Blue shampoo for the treatment of a diagnosis of ‘tinea versicolor”. He reports none of the treatments worked.

Rash Body Before treatment
Rash Body After Treatment

What's Your Diagnosis?

Diagnosis: Confluent and Reticulated Papillomatosis of Carteaud and Gougerot, a.k.a. “CARP”

Information from

(Dr. Crutchfield is a Dermatology Editor for

Contributors: Elizabeth B. Wallace MD, Susan Burgin MD


Confluent and reticulated papillomatosis (also known as confluent and reticulated papillomatosis of Gougerot and Carteaud or Gougerot-Carteaud syndrome) is a rare cutaneous dermatosis of undetermined etiology with clinical features resembling acanthosis nigricans and tinea versicolor. It has been speculated that the disorder may be due to an endocrine disturbance, abnormal keratinocyte differentiation and maturation, an abnormal host reaction to bacteria or fungi, or that it may be hereditary. Onset is usually at puberty, but the age range of those affected has been reported to be from 5-63 years.

It is clinically characterized by brown, hyperkeratotic or verrucous, thin papules that usually affect the upper central trunk and axillae. These papules coalesce into reticulated plaques. The lesions are usually asymptomatic but may be pruritic. The disorder typically affects young adults. While responsive to treatment, the disease is usually chronic and marked by exacerbations and remissions.

Diagnostic criteria have been proposed by Davis et al (Ann Dermatol. 2014 Jun;26[3]:409-410) due to frequent misdiagnosis of this condition and include the following: (i) clinical findings include scaly brown macules and patches, with at least some appearing reticulated and papillomatous; (ii) involvement of the upper trunk and neck; (iii) negative fungal staining of the scales; (iv) no response to antifungal treatment; and (v) excellent response to minocycline. A second research group proposed revised criteria to include clinical involvement of the flexural areas and management with antibiotics, rather than minocycline specifically.


There are several abx protocols used to treat CARP, found in textbooks and on the internet.

In this particular case I gave the patient minocycline, 100mg tabs, 1 P.O. BID x 2 months with complete resolution.


The possibility that this is due to skin infection is supported by the success of treatment with antibiotics. Dietzia papillomatosis is the current leading infectious candidate. This is a gram-positive actinomycete that was first isolated from a patient with confluent and reticulated papillomatosis in 2005 (

online appointments

Charles Crutchfield III M.D. Eagan Dermatologist

For more dermatology cases-of-the-month visit Dr. Crutchfield's Case of the Month Archive

Look Good, Feel Great with Beautiful Skin ™

Dr. Crutchfield is a member or graduate of these prestigious organizations.

Demonstrating his education, experience, and commitment to providing patients with the highest quality medical & cosmetic dermatologic care.
When choosing your physician, demand nothing less. Remember..... "Quality Matters"

Crutchfield Dermatology Location
Crutchfield Dermatology Logo
top 100 places to work

Crutchfield Dermatology

1185 Town Centre Drive, Suite 101
Eagan, MN 55123 USA

Phone: (651) 209-3600 Fax: (651) 209-3601

Hours: Monday-Friday 8am-5pm

Newsletter Sign Up

Sent once or twice a month with the latest in skin care news and treatments.

©Crutchfield Dermatology
All Photographs copyright protected, unauthorized use is prohibited.

Web Site by Arbor Bay Marketing

Alpha Omega Alpha Honor Medical Society