Confluent and Reticulated Papillomatosis (CARP)

CARP (Gougerot-Carteaud Syndrome)

Overview

Confluent and reticulated papillomatosis (CARP), also known as Gougerot-Carteaud syndrome, is an uncommon dermatosis characterized by hyperpigmented, slightly verrucous (rough) papules and plaques that become confluent centrally and reticulated (net-like) at the periphery. It most commonly affects the central chest, upper back, and neck of young adults. The cause is debated but may involve abnormal keratinization, with Dietzia species or Malassezia furfur playing a possible role.

Key Symptoms

  • Brown, slightly rough or velvety papules and plaques
  • Confluent (merged together) centrally with a reticulated (net-like) pattern at the edges
  • Most common on the central chest, upper back, and neck
  • Gradually spreading and persistent
  • Usually asymptomatic, though mild itching may occur
  • Often mistaken for tinea versicolor or acanthosis nigricans

Affected Areas

Central chest, Upper back (interscapular area), Neck, Shoulders, Axillae

Care Instructions

  1. See a dermatologist for evaluation — CARP is often misdiagnosed as tinea versicolor.
  2. Oral minocycline (or other tetracyclines) is the most effective treatment and is considered first-line.
  3. Oral azithromycin is an alternative if tetracyclines are not tolerated.
  4. Topical retinoids or antifungals may provide partial improvement.
  5. Recurrence is common after discontinuation of treatment.
  6. A trial of antifungal therapy may be appropriate to rule out tinea versicolor.

Medical Disclaimer: This information is for educational purposes only and does not replace professional medical advice. Always consult a qualified dermatologist for diagnosis and treatment.

Prevalence: Uncommon; most often affects young adults aged 15-30, with a slight female predominance