title: A diagnostic method for herpes simplex keratitis by simultaneous measurement of viral DNA and virus-specific secretory IgA in tears: an evaluation.
abstract: OBJECTIVE
  We performed simultaneous measurement of herpes simplex virus (HSV) DNA by real-time polymerase chain reaction (real-time PCR) and of HSV-specific secretory IgA antibody (HSV-sIgA) by enzyme-linked immunosorbent assay (ELISA) in tears obtained using Schirmer strips in order to investigate its diagnostic efficacy for herpes simplex keratitis (HSK).
  
  
  METHODS
  A total of 59 affected eyes from 59 patients with clinically suspected HSK (HSK group) and 23 eyes from 23 healthy volunteers (control group) were enrolled in this study. The HSK group was divided into five subgroups: dendritic/geographic keratitis, disciform keratitis, necrotizing keratitis, atypical keratitis, and others. The tear samples were taken using Schirmer strips to determine the HSV DNA and HSV-sIgA levels.
  
  
  RESULTS
  The overall sensitivity and specificity were 55.8 and 100 % for HSV DNA and 49.2 and 82.6 % for HSV-sIgA. The HSV DNA levels in the disciform keratitis subgroup (median, 3.1 × 10(2) copies/sample) were significantly lower than those in the dendritic/geographic keratitis subgroup (median, 2.3 × 10(4) copies/sample) (P < 0.05, Mann-Whitney test). The HSV-sIgA levels in the disciform keratitis subgroup (median, 50.0 NU/ml) were significantly higher than those in the control group (median, 18.0 NU/ml) (P < 0.05, Steel test). The positive and negative predictive values obtained by simultaneous measurement of HSV DNA and sIgA were 90.9 and 61.3 %, respectively.
  
  
  CONCLUSIONS
  The combination of laboratory detection of HSV DNA by real-time PCR and of HSV-sIgA by ELISA using tear samples enables higher reliability in diagnosing the subgroups of HSK, although the HSV DNA value is relatively lower in disciform HSK than in dendritic/geographic HSK.
authors.affiliation: Division of Ophthalmology, Department of Visual Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-Kamicho, Itabashi-ku, Tokyo, 173-8610, Japan. shojig3589eye@athena.ocn.ne.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Shoji
authors.affiliation: Division of Ophthalmology, Department of Visual Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-Kamicho, Itabashi-ku, Tokyo, 173-8610, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Sakimoto
authors.affiliation: Division of Ophthalmology, Department of Visual Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-Kamicho, Itabashi-ku, Tokyo, 173-8610, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Inada
authors.affiliation: Department of Ophthalmology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kamei
authors.affiliation: Department of Ophthalmology, Tokyo Women's Medical University Medical Center East, Tokyo, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Matsubara
authors.affiliation: Department of Ophthalmology, Tokyo Women's Medical University School of Medicine, Tokyo, Japan.
authors.forename: Etsuko
authors.initials: E
authors.lastname: Takamura
authors.affiliation: Division of Ophthalmology, Department of Visual Sciences, Nihon University School of Medicine, 30-1 Oyaguchi-Kamicho, Itabashi-ku, Tokyo, 173-8610, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Sawa
mesh_terms: D000914:Antibodies, Viral / Q000032:analysis*; D003319:Corneal Stroma / Q000000981:diagnostic imaging* / Q000821:virology; D004279:DNA, Viral / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000276:immunology*; D016849:Keratitis, Herpetic / Q000175:diagnosis* / Q000821:virology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D018139:Simplexvirus / Q000235:genetics* / Q000276:immunology; D013666:Tears / Q000737:chemistry*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D007071:Immunoglobulin A, Secretory
keywords: Herpes simplex virus; Keratitis; Real-time polymerase chain reaction; Secretory IgA; Tear fluid