Confluent and Reticulated Papillomatosis

For educational purposes, here is a hypothetical example of a patient

History

This 27 year old male patient has a ten-year history of a hyperpigmented, scaly, non-itchy skin condition, which began on his chest and has slowly spread 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 treatments include topical anti fungal creams 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. Also Face, neck, chest, and back. Lesions are confluent centrally and reticulated peripherally.

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.

Laboratory Data A microscope slide was negative for fungus. No fluorescence was demonstrated with a Wood's lamp examination.

Microscopic Histopathology

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

Diagnosis

Confluent and reticulated papillomatosis

Discussion

In 1927, Gougerot and Carteaud described the clinical features of confluent and reticulated papillomatosis.  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.  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. Microscopically, the hyperpigmentation is due to an increased number of melanosomes in the hyperkeratotic horny layer.

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. Oral antibiotic treatment has also been effective. 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, Z pack 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 consistently effective.