title: Tissue eosinophilia: not an indicator of drug-induced subacute cutaneous lupus erythematosus.
abstract: OBJECTIVE
  To investigate whether tissue eosinophilia is a differentiating histopathologic feature of drug-induced subacute cutaneous lupus erythematosus (DI-SCLE) compared with non-DI-SCLE.
  
  
  METHODS
  Retrospective medical record review with prospective blinded histopathologic analysis.
  
  
  METHODS
  University-affiliated dermatology and dermatopathology practice.
  
  
  METHODS
  Fifty-nine patients with SCLE were divided into DI (n = 15) and non-DI (n = 44) groups.
  
  
  METHODS
  A dermatopathologist masked to the etiologic associations reviewed corresponding histopathologic specimens. For each patient, an eosinophil ratio was calculated as the mean eosinophil score (averaging eosinophil counts from 10 high-power histologic fields) divided by the intensity of inflammation. Eosinophil ratios for both groups were compared using the Mann-Whitney test.
  
  
  RESULTS
  No significant difference was found in mean eosinophil ratios in the DI vs non-DI groups (0.11 vs 0.004; P = .34). Mucin deposition was present in both populations and was not significantly different (P = .18). The inflammatory infiltrate was superficial and deep in 10 patients (67%) in the DI group vs 24 (55%) in the non-DI group. Periadnexal inflammation was observed in 12 patients (80%) in the DI group vs 37 (84%) in the non-DI group, and basal layer liquefaction with dyskeratosis was seen in 15 patients (100%) in the DI group and in 37 (84%) in the non-DI group.
  
  
  CONCLUSIONS
  Tissue eosinophilia is not a differentiating histopathologic feature of DI-SCLE. Careful review of a patient's drug history in correlation with clinical findings remains the standard for identifying a drug as an etiologic or exacerbating factor in patients with SCLE.
authors: Department of Pathology and Laboratory Medicine, University of Louisville, 530 S Jackson St, Louisville, KY 40202, USA. pbhill01@louisville.edu
authors: Paul B
authors: PB
authors: Hillesheim
authors: Soon
authors: S
authors: Bahrami
authors: Brooke G
authors: BG
authors: Jeffy
authors: Jeffrey P
authors: JP
authors: Callen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D003875:Drug Eruptions / Q000473:pathology*; D004802:Eosinophilia / Q000209:etiology / Q000473:pathology*; D004804:Eosinophils; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008178:Lupus Erythematosus, Cutaneous / Q000097:blood / Q000139:chemically induced* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000032:analysis; D012189:Retrospective Studies; D016037:Single-Blind Method; D018709:Statistics, Nonparametric; D055815:Young Adult
chemical_list: D009077:Mucins