title: In-stent restenosis exacerbated by drug-induced severe eosinophilia after second-generation drug-eluting stent implantation.
abstract: BACKGROUND
  In-stent restenosis (ISR) is still a recognized clinical problem in the era of drug-eluting stent (DES). Some previous studies have suggested that circulating eosinophils play an important role in both restenosis and thrombosis after DES implantation. However, the contribution of eosinophils to the pathogenesis of ISR has not yet been concisely clarified.
  
  
  METHODS
  We present the case of an 83-year-old male Japanese patient with ISR exacerbated by drug-induced severe eosinophilia. He had previous histories of coronary stent implantations by DES and was referred to our hospital because of erythema with severe eosinophilia (maximum was 6500/μl [48% of total white blood cell count]). Around the same time, the patient developed ISR, for which a stent was deployed 2 years earlier. Arterial wall injury due to the increase in circulating eosinophils was verified in several findings, such as the increase of D-dimer and brain natriuretic peptide. In addition, the histology of the resected tissue from erythema demonstrated that the nuclei of endothelial cells were swollen where eosinophils and lymphocytes heavily infiltrated into the extravascular space, suggesting the presence of vascular injury. This injury due to the increase in circulating eosinophils may have a marked impact on the pathologic process of ISR in DES implantation.
  
  
  CONCLUSIONS
  Just a few anecdotal reports are available of ISR occurring in the setting of hypereosinophilia. The clarification of the mechanism in this patient provides a new effective therapeutic strategy against ISR in the setting of DES implantation.
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Yagi
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Amiya
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Jiro
authors.initials: J
authors.lastname: Ando
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Dermatology, Jikei University School of Medicine, Tokyo, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Yanaba
authors.affiliation: Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Masako
authors.initials: M
authors.lastname: Ikemura
authors.affiliation: Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Fukayama
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
mesh_terms: D000369:Aged, 80 and over; D001706:Biopsy; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D023903:Coronary Restenosis / Q000175:diagnosis / Q000209:etiology*; D003331:Coronary Vessels / Q000473:pathology*; D003937:Diagnosis, Differential; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D004802:Eosinophilia / Q000139:chemically induced* / Q000175:diagnosis; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects; D008297:Male; D017239:Paclitaxel / Q000009:adverse effects*; D011474:Prosthesis Design; D012720:Severity of Illness Index; D020123:Sirolimus / Q000009:adverse effects*; D050257:Tubulin Modulators / Q000009:adverse effects
chemical_list: D007166:Immunosuppressive Agents; D050257:Tubulin Modulators; D017239:Paclitaxel; D020123:Sirolimus