Cross-comparison of patch test and lymphocyte proliferation responses in patients with a history of acute generalized exanthematous pustulosis

Am J Dermatopathol. 2005 Aug;27(4):343-6. doi: 10.1097/01.dad.0000160982.75176.6c.

Abstract

An adverse cutaneous reaction to a systemically administered drug may rarely manifest as acute generalized exanthematous pustulosis (AGEP). Several recent reports have documented positive patch test results in patients with a history of AGEP, while two have demonstrated drug-specific in vitro lymphocyte proliferative responses. These findings suggest that drug-specific T cells mediate AGEP. We describe two patients with a history of AGEP who each demonstrated positive patch test results specific for the inciting drug: Patient #1 to the antibiotic metronidazole, and Patient #2 to the calcium channel-blocker diltiazem. Histologic examination of biopsy specimens taken from the patch test sites of these patients revealed spongiotic dermatitis and perivascular lymphocytes consistent with a delayed-type hypersensitivity reaction, rather than demonstrating subcorneal neutrophilic pustules more typical of AGEP. In vitro testing by measuring peripheral T cell proliferative responses to chemically purified drug correlated with the clinical response. In a direct cross-comparison, patch test results were shown to correlate with in vitro lymphocyte proliferative responses in two patients with a history of AGEP to different drugs. These findings provide additional evidence that the pathogenesis of AGEP involves a T cell-mediated immune response.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Anti-Infective Agents / adverse effects
  • Calcium Channel Blockers / adverse effects
  • Cell Proliferation
  • Diltiazem / adverse effects
  • Drug Eruptions / immunology*
  • Drug Eruptions / pathology
  • Drug Hypersensitivity / immunology*
  • Female
  • Humans
  • Immunologic Techniques*
  • Male
  • Metronidazole / adverse effects
  • Patch Tests*
  • T-Lymphocytes / immunology*

Substances

  • Anti-Infective Agents
  • Calcium Channel Blockers
  • Metronidazole
  • Diltiazem