Challenges in diagnosing confluent and reticulated papillomatosis: a case of atypical lesions distribution.

Gougerot-Carteaud Syndrome (Confluent and Reticulate Papillomatosis, CARP) is a rare dermatological condition characterized by coalescent reticulate papules predominantly affecting the upper trunk and neck. The etiology remains debated, with hypotheses ranging from keratinization disorders to bacterial and fungal infections, endocrine abnormalities, and genetic predispositions. This report presents the case of an 18-year-old male with pruritic, maculopapular, and scaly lesions unresponsive to antifungal and antibiotic therapies. Histopathological examination revealed hyperkeratosis, acanthosis, and papillomatosis, leading to a diagnosis of CARP. Despite initial treatment with doxycycline, the patient showed significant improvement only after isotretinoin therapy, suggesting a non-bacterial etiology. The consanguinity in the patient's family underscores the potential for genetic factors in CARP's pathogenesis. This case highlights the diagnostic and therapeutic challenges associated with CARP and emphasizes the need for further research into its underlying mechanisms.