Idiopathic Papular Dermatitis in the Spectrum of Chronic Papular Eruptions (Subacute Prurigo): Reappraisal and Diagnostic Algorithm

Dermatology. 2019;235(3):205-212. doi: 10.1159/000496540. Epub 2019 Mar 5.

Abstract

Background: The clinical diagnosis of papular eruptions is common but poorly characterized in the literature and the etiology is often unknown.

Objective: To characterize the entity of idiopathic papular dermatitis in the spectrum of chronic papular eruptions.

Methods: The cohort consisted of patients who presented at a tertiary medical center in 2005-2014 with a papular eruption of at least 4 months' duration. Findings on histological analysis and thorough clinical investigation, performed in all cases, were collected. The patients completed a questionnaire on disease course and outcome.

Results: Sixty-five patients were included. Sixteen patients showed morphological changes over time and were excluded. Investigations in the remaining 49 patients with a consistent papular morphology yielded a well-defined diagnosis in 23 (46%). Twenty-six patients (54%; 14 male) were diagnosed with idiopathic papular dermatitis. Their mean age at onset was 61.6 ± 14.4 years and the mean duration of disease 3.11 ± 2.726 years. In 60%, the rash resolved with conservative treatment during follow-up (mean 4.35 ± 2.53 years).

Conclusions: Chronic papular eruptions encompass a wide range of skin diseases. In more than half of the cases, the etiopathogenesis remains unclear. On the basis of our results, we propose a diagnostic algorithm for idiopathic papular dermatitis.

Keywords: Dermatitis; Idiopathic papular dermatitis; Papular eruptions.

MeSH terms

  • Academic Medical Centers
  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Algorithms
  • Biopsy, Needle
  • Chronic Disease
  • Cohort Studies
  • Dermatitis / epidemiology*
  • Dermatitis / pathology*
  • Dermatitis / physiopathology
  • Female
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Prevalence
  • Prognosis
  • Prurigo / epidemiology*
  • Prurigo / pathology*
  • Prurigo / physiopathology
  • Retrospective Studies
  • Severity of Illness Index
  • Sex Distribution
  • Surveys and Questionnaires*
  • Tertiary Care Centers
  • United States