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Confluent and Reticulate Papillomatosis

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Confluent and Reticulate Papillomatosis
Erick A. Mafong M.D.
Dermatology Online Journal 7(1): 13

Department of Dermatology, New York University

PATIENT: 29-year-old man

DURATION: Twelve years

DISTRIBUTION: Face, neck, chest, and back


The patient has a twelve-year history of a hyperpigmented, scaly, non-pruritic skin condition, which began on his chest and has slowly expanded to involve his back, neck, and face.. He denies a family history of similar lesions. He does not have a history of diabetes mellitus or thyroid disease. Prior unsuccessful treatments include topical clotriamazole cream and selenium sulfide solution. Current treatment is minocycline 100 mg twice daily.

Physical Examination

Hyperpigmented, hyperkeratotic, patches and plaques with scale were present on the neck, mid-back, and sternal area. Lesions were confluent centrally and reticulated peripherally.

Figure 1Figure 2

Laboratory Data

A potassium hydroxide preparation was negative for hyphae. No fluorescence was demonstrated with a Wood's lamp examination.


There was mild hyperkeratosis, papillomatosis, and focal acanthosis present between elongated dermal papillae. There was a superficial perivascular infiltrate of lymphocytes.


Confluent and reticulated papillomatosis


In 1927, Gougerot and Carteaud described the clinical features of confluent and reticulated papillomatosis.[1] This is a rare condition, in which the lesions appear as 1-to-5-mm gray-brown, hyperkeratotic papules and patches that become confluent centrally and reticulated at the periphery.[2] The first lesions usually appear in the intermammary area and the midback. Subsequent lesions may develop in the neck, axillae, and epigastrium. This condition is more common in women and people of darker pigmentation. The majority of cases are sporadic, although familial cases have been reported. Ultrastructurally, the hyperpigmentation is due to an increased number of melanosomes in the hyperkeratotic horny layer.[3]

The cause of confluent and reticulated papillomatosis is unknown and often it does not respond well to therapy. Confluent and reticulated papillomatosis has been found to be associated with endocrine abnormalities, such as diabetes mellitus and thyroid disease. A case report demonstrated an association with ultraviolet light exposure. Also, an abnormal tissue reaction to Pityrosporum orbiculare colonization has been suggested. This hypothesis was supported by the clinical resemblance of confluent and reticulated papillomatosis to lesions of tinea versicolor and to studies which demonstrated the presence of P. orbiculare in the lesions. Some cases of confluent and reticulated papillomatosis have responded to either systemic or topical antifungal therapy. A disorder of keratinization has also been suggested due to the response of this disorder to retinoid therapy. Topical tretinoin has been useful as have the systemic retinoids etretinate and isotretinoin.[4] Oral antibiotic treatment has also been effective.[5,6] In 1965, Carteaud was the first to describe the successful treatment of confluent and reticulated papillomatosis with minocycline. Since then, several other reports also support its use and cite the anti-inflammatory and immunomodulatory effects of certain antibiotics. Most recently, azithromycin has been effective in the treatment of confluent and reticulated papillomatosis. Overall, many treatments have been utilized for confluent and reticulated papillomatosis but none has been universally effective or subjected to controlled clinical trials.


1. Gougerot H, Carteaud A. Papillomatose pigmentee innominee. Bull Soc Fr Dermatol Syphilol 1927;34:719.

2. Vassileva S, Pramatarov K, Popova L. Ultraviolet light-induced confluent and reticulated papillomatosis. J Am Acad Dermatol 1989;21(2 Pt 2):413-4. PubMed

3. Jimbow M, Talpash O, Jimbow K. Confluent and reticulated papillomatosis: clinical, light and electron microscopic studies. Int J Dermatol 1992;31(7):480-3. PubMed

4. Baalbaki SA, Malak JA, al-Khars MA. Confluent and reticulated papillomatosis. Treatment with etretinate. Arch Dermatol 1993;129(8):961-3. PubMed

5. Montemarano AD, Hengge M, Sau P, Welch M. Confluent and reticulated papillomatosis: response to minocycline. J Am Acad Dermatol 1996;34(2 Pt 1):253-6. PubMed

6. Gruber F, Zamolo G, Saftic M, Peharda V, Kastelan M. Treatment of confluent and reticulated papillomatosis with azithromycin [letter] Clin Exp Dermatol 1998;23(4):191. PubMed

© 2001 Dermatology Online Journal