title: Recall injection-site reactions associated with etanercept therapy: report of two new cases with immunohistochemical analysis.
abstract: Injection site reactions (ISRs) are the most common adverse effect reported with etanercept therapy. It has been observed that some patients treated with etanercept develop ''recall ISRs'', that are reactions at sites where etanercept was previously injected after the last injection. Etanercept-associated recall ISRs have been scarcely published. We report two patients with rheumatoid arthritis who developed recall ISRs during etanercept therapy. Biopsy specimens from ISRs demonstrated a superficial perivascular lymphocytic infiltrated with a few eosinophils. Immunohistochemical study in both cases revealed that T cells bearing a CD4+ phenotype mostly composed the inflammatory infiltrate. Our observations suggest that ISRs may be mediated by classic cellular-hypersensitivity reactions directed by CD4+ T lymphocytes.
authors.affiliation: Department of Dermatology, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria, Santander, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: González-López
authors.forename: V M
authors.initials: VM
authors.lastname: Martínez-Taboada
authors.forename: M C
authors.initials: MC
authors.lastname: González-Vela
authors.forename: R
authors.initials: R
authors.lastname: Blanco
authors.forename: H
authors.initials: H
authors.lastname: Fernández-Llaca
authors.forename: V
authors.initials: V
authors.lastname: Rodríguez-Valverde
authors.forename: J F
authors.initials: JF
authors.lastname: Val-Bernal
mesh_terms: D018501:Antirheumatic Agents / Q000009:adverse effects*; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology; D003875:Drug Eruptions / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D004487:Edema / Q000139:chemically induced / Q000276:immunology / Q000473:pathology; D004890:Erythema / Q000139:chemically induced / Q000276:immunology / Q000473:pathology; D000068800:Etanercept; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000139:chemically induced / Q000276:immunology / Q000473:pathology; D007074:Immunoglobulin G / Q000009:adverse effects*; D007279:Injections, Subcutaneous / Q000009:adverse effects; D008875:Middle Aged; D018124:Receptors, Tumor Necrosis Factor
chemical_list: D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D000068800:Etanercept