title: The usefulness of measuring tear periostin for the diagnosis and management of ocular allergic diseases.
abstract: Chronic ocular allergic diseases such as vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are accompanied by serious comorbidities; however, the underlying pathogenesis remains obscure. Furthermore, diagnosing conjunctival lesions in patients with atopic dermatitis and estimating the severity in AKC are important for the treatment of ocular allergic diseases.
  
  
  
  We addressed whether periostin, a novel mediator and biomarker in allergic inflammation, is involved in the pathogenesis of ocular allergic diseases and whether periostin can be a biomarker for these diseases.
  
  
  
  We investigated tear periostin in patients with seasonal allergic conjunctivitis (SAC), VKC, and AKC and allergic patients without conjunctivitis and compared it with tear IL-13 and serum periostin. Furthermore, in patients with AKC, we measured tear periostin before and after topical treatment with tacrolimus.
  
  
  
  Tears from patients with ocular allergic disease showed significantly high periostin levels than did tears from allergic patients without conjunctivitis and from patients with AKC, VKC, and SAC in descending order. Tear periostin was associated with serious comorbidities such as large papilla formation and corneal damage in AKC, although both tear IL-13 and serum periostin had little to no such abilities. Furthermore, after topical tacrolimus treatment, tear periostin tended to decrease in most patients with AKC along with their clinical improvement.
  
  
  
  Periostin produced in conjunctival tissues stimulated by IL-13 may contribute to the pathogenesis of ocular allergic diseases. Furthermore, tear periostin can be potentially applied as a biomarker to diagnose conjunctivitis in allergic patients and to evaluate disease severity as well as the efficacy of treatments in AKC.
authors.affiliation: Department of Ophthalmology, Tsurumi University School of Dental Medicine, Tsurumi, Yokohama, Japan. Electronic address: fujishima117@gmail.com.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Fujishima
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development Laboratory, Tokyo, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Okada
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development Laboratory, Tokyo, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Matsumoto
authors.affiliation: Ryogoku Eye Clinic, Tokyo, Japan; Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Kazumi
authors.initials: K
authors.lastname: Fukagawa
authors.affiliation: Department of Ophthalmology, Tokyo Dental College, Ichikawa General Hospital, Ichikawa, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Igarashi
authors.affiliation: Department of Allergy and Clinical Immunology, National Research Institute for Child Health and Development Laboratory, Tokyo, Japan.
authors.forename: Akio
authors.initials: A
authors.lastname: Matsuda
authors.affiliation: Shino-Test Corporation, Sagamihara, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Ono
authors.affiliation: Department of Laboratory Medicine, Saga Medical School, Saga, Japan.
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Ohta
authors.affiliation: Division of Medical Biochemistry, Department of Biomolecular Sciences, Saga Medical School, Saga, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Mukai
authors.affiliation: Department of Dermatology, Toho University School of Medicine, Tokyo, Japan.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Yoshikawa
authors.affiliation: Department of Otorhinolaryngology, Toho University School of Medicine, Tokyo, Japan. Electronic address: kizuhara@cc.saga-u.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Izuhara
mesh_terms: D015415:Biomarkers; D016022:Case-Control Studies; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002908:Chronic Disease; D003233:Conjunctivitis, Allergic / Q000175:diagnosis / Q000378:metabolism; D019468:Disease Management; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000378:metabolism; D005128:Eye Diseases / Q000175:diagnosis* / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis* / Q000378:metabolism*; D018793:Interleukin-13 / Q000097:blood / Q000378:metabolism; D008297:Male; D013666:Tears / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D015815:Cell Adhesion Molecules; D018793:Interleukin-13; C512835:POSTN protein, human
keywords: Atopic keratoconjunctivitis; IL-13; biomarker; periostin; serum; tear