An African American man, aged 38 years, presents for evaluation an extensive rash involving his chest and back. The dermatitis began as a small patch several months ago and spread rapidly despite treatment with topical ketoconazole shampoo and triamcinolone cream. He denies significant pruritus. Examination reveals hyperpigmented patches with scale on the affected areas. Fluorescence was not observed under Wood’s light, and skin scrapings did not reveal hyphae or spores.
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Confluent and reticulated papillomatosis (CRP) was initially described by French dermatologists Gougerot and Carteaud in 1927 under the name papillomatose pigmentée innominée.1 The first case in the United States was reported in 1937, and the condition became known as CRP of Gougerot and Carteaud.2 CRP is a benign acquired ichthyosiform dermatitis,3 presenting with brownish patches that are confluent centrally and reticulated peripherally. Pruritis is minimal, and the disorder is most common in African Americans.4
The cause of CRP is unknown. The differential diagnosis includes tinea versicolor; however, unlike tinea versicolor, CRP dermatitis does not fluoresce under Wood’s light, skin scrapings are negative for spores and hyphae, and response to antifungal medications is minimal. CRP may also resemble acanthosis nigricans both clinically and histopathologically; however, there is a greater degree of pigmentation microscopically in acanthosis nigricans, and it usually does not involve the trunk.5
The treatment of choice for CRP is minocycline, which was first described in 1996.6 Successful treatment with minocycline has been proposed as a diagnostic criterion.7 The patient in this case was given minocycline at a dose of 100 mg twice daily and had complete resolution of the rash within 6 weeks.
Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia. He practices dermatology in Hazleton, Pennsylvania.
1. Gougerot H, Carteaud A. Papillomatose pigmentée innominée. Bull Soc Fr Dermatol Syphiligr. 1927;34:719-721.
2. Wise F. Confluent and reticular papillomatosis (Gougerot-Carteaud). Arch Derm Syphilol. 1937;35:550.
3. Tamraz H, Raffoul M, Kurban M, Kibbi AG, Abbas O. Confluent and reticulated papillomatosis: clinical and histopathological study of 10 cases from Lebanon. J Eur Acad Dermatol Venereol. 2013;27(1):e119-e123.
4. el-Tonsy MH, el-Benhawi MO, Mehregan AH. Confluent and reticulated papillomatosis. J Am Acad Dermatol. 1987;16(4):893-894.
5. Park YJ, Kim SJ, Kang HY, Lee E-S, Kim YC. Differentiating confluent and reticulated papillomatosis from acanthosis nigricans. J Am Acad Dermatol. 2015;72(5 Suppl 1):AB45.
6. Montemarano AD, Hengge M, Sau P, Welch M. Confluent and reticulated papillomatosis: response to minocycline. J Am Acad Dermatol. 1996;34(2 Pt 1):253-256.
7. Davis MD, Weenig RH, Camilleri MJ. Confluent and reticulate papillomatosis (Gougerot-Carteaud syndrome): a minocycline-responsive dermatosis without evidence for yeast in pathogenesis. A study of 39 patients and a proposal of diagnostic criteria. Br J Dermatol. 2006;154(2):287-293.