Clinical Challenge: Widespread Skin Pigmentation

Confluent and reticulated papillomatosis (CRP) was first described in 1927 by the French dermatologists Gougerot and Carteaud.1 It occurs predominantly in young adults and teenagers. The condition manifests as scaling brown macules and patches that are at least in part reticulated...

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Confluent and reticulated papillomatosis (CRP) was first described in 1927 by the French dermatologists Gougerot and Carteaud.¹ It occurs predominantly in young adults and teenagers. The condition manifests as scaling brown macules and patches that are at least in part reticulated and papillomatous. Sites of involvement are the upper trunk, axillae, and neck. The entire back and chest may be involved. Extensive cases may also extend to the shoulders and pubic areas.^2-4

The histologic features of CRP include hyperkeratosis, parakeratosis, papillomatosis, and acanthosis with mild-to-moderate increase in pigmentation. Sparse perivascular lymphocytic inflammation and dilation of superficial vessels may be noted in the dermis.⁵ Dermoscopic findings include brownish pigmentation and whitish scales with poorly defined edges. Depressions and elevations (sulci and gyri) correspond to papillomatosis.⁶ 

The diagnosis of CRP is often made clinically. Davis et al proposed the following diagnostic criteria based on a study on 39 patients⁷:

• Clinical findings of scaly brown macules and patches, with at least some appearing reticulated and papillomatous

• Involvement of the upper trunk and neck

• Negative fungal staining of scales

• No response to antifungal treatment 

• Excellent response to minocycline

Other conditions that may mimic CRP include tinea versicolor and acanthosis nigricans. Indeed, because of their similar and overlapping clinical features, Decroix et al suggested that CRP and acanthosis nigricans are a spectrum of the same entity.⁸ Some cases of CRP have been associated with hyperinsulinemia, hypothyroidism, diabetes mellitus, obesity, and Stein-Leventhal syndrome (polycystic ovarian syndrome).^9-11

Topical therapies include keratolytics and retinoids.⁴ Oral minocycline (50 mg twice a day for 6 weeks) is highly effective against CRP and is considered a first-line treatment.¹²

Nejib Doss, MD, is a dermatologists practicing in Tunis, Tunisia. Kofi A. Brifo, MD; Koma S. Jehu-Appiah, MD; and Edmundo N. Delle, MD, are dermatologists practicing at the Rabito Clinic in Accra, Ghana. Stephen Schleicher, MD, is director of the DermDox Center for Dermatology in Pennsylvania, associate professor of medicine at Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.

References

1. Gougerot H, Carteaud A. Papillomatose pigmentée innominée [Unclassified pigmented papillomatosis]. Cas pour diagnostic. Bulletin de la Société Française de Dermatologie et de Syphiligraphie. 1927;34:712–719.

2. Ahogo KC, Gbery PI, Bamba V, Kouassi YI, Ecra EJ, Kouassi KA, Allou AS. Confluent and reticulated papillomatosis of gougerot-carteaud on black skin: two observations. Case Rep Dermatol Med. 2016;2016:2507542. doi:10.1155/2016/2507542

3. Shashikumar BM, Harish MR, Deepadarshan K, Kavya M, Mukund P, Kirti P. Confluent and reticulate papillomatosis: a retrospective study from southern India. Indian Dermatol Online J. 2021;12(1):90-96.

4. Lim JHL, Tey HL, Chong WS. Confluent and reticulated papillomatosis: diagnostic and treatment challenges. Clin Cosmet Investig Dermatol. 2016;9: 217-223. doi:10.2147/CCID.S92051

5. Cho YM, Jung KE, Koo DW, Lee JS. Clinical and histopathologic study of confluent and reticulated papillomatosis by anatomic site and age. Ann Dermatol. 2018;30(5):550-555.  doi:10.5021/ad.2018.30.5.550

6. Filho FB, Quaresma MV, Rezende FC, Kac BK, da Costa Nery JA, Azulay-Abulafia L. Confluent and reticulate papillomatosis of Gougerot-Carteaud and obesity: dermoscopic findings. An Bras Dermatol. 2014;89(3):507–509. doi:10.1590/abd1806-4841.20142705

7. Davis MDP, 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. doi:10.1111/j.1365-2133.2005.06955.x

8. Decroix J, Bourlond A, Minet A, Eggers S. [Gougerot-Carteaud confluent and reticulated papillomatosis associated with pseudoacanthosis nigricans: the same entity?] Ann Dermatol Venereol. 1987;114(2):223-226.

9. Fukumoto T, Kozaru T, Sakaguchi M, Oka M. Concomitant confluent and reticulated papillomatosis and acanthosis nigricans in an obese girl with insulin resistance successfully treated with oral minocycline: case report and published work review. J Dermatol. 2017;44(8):954-958. doi:10.1111/1346-8138.13819

10. Lahouel M,  Aounallah A, Mokni  S,  Belajouza C, Denguezli M. Confluent and reticulated papillomatosis associated with obesity: case series of three patients successfully treated with oral doxycycline. Dermatol Pract Concept. 2021; 11(2):e2021006. doi:10.5826/dpc.1102a06

11. Fite LP, Cohen PR. Polycystic ovarian syndrome-associated confluent and reticulated papillomatosis: report of a patient successfully treated with azithromycin. J Clin Aesthet Dermatol. 2017;10(9):30-35.

12. Le C, Bedocs PM. Confluent and reticulated papillomatosis. StatPearls. StatPearls Publishing; 2021. Updated August 10, 2020. Accessed July 29, 2021. https://www.ncbi.nlm.nih.gov/books/NBK459130/.