[Reticular pigmented anomaly of the flexures. Dowling-Degos disease of the intertrigo type in association with acne inversa].

Reticulated pigmented anomaly of the flexures (Dowling-Degos disease) is a rare autosomal-dominant genodermatosis with variable penetrance that is characterized by reticulated hyperpigmentation of the flexures. Acne inversa has been previously described in the literature under several synonyms, such as acne triad, acne tetrad and hidradenitis suppurativa. Acne inversa is an inflammation affecting the pilosebaceous units of the flexures. We report a case of Dowling-Degos disease in association with acne inversa. The association of these diseases has been described several times and it appears not to be coincidental. Pathogenetic mechanisms leading to this coincidence are discussed.