title: Evaluation of immunohistochemistry in identifying Bartonella henselae in cat-scratch disease.
abstract: Cat-scratch disease (CSD) is largely due to infection with Bartonella henselae. Microbiologic detection is difficult, and molecular testing is not readily available. A monoclonal antibody (mAB) to B henselae has become commercially available. We evaluated the usefulness of immunohistochemical analysis (IHC) for diagnosing CSD on surgical specimens and compared these results with polymerase chain reaction (PCR) detection and serologic testing for B henselae. We studied 24 formalin-fixed, paraffin-embedded (FFPE) cases of lymphadenitis with histologic and/or clinical suspicion of CSD. Control cases included 14 cases of lymphadenopathy other than CSD. FFPE tissue sections were evaluated with an mAB to B henselae, Steiner silver stain (SSS), and PCR that targeted B henselae and Bartonella quintana. Positive cases were as follows: SSS, 11 (46%); PCR, 9 (38%); and IHC, 6 (25%). Only 2 cases (8%) were positive for all 3 studies. All control cases were negative for IHC and PCR. The diagnostic sensitivity of these 3 tests is low for CSD. SSS seems to be the most sensitive test but is the least specific. PCR is more sensitive than IHC and may, therefore, serve as a helpful second-line test on all IHC- cases.
authors.affiliation: Department of Pathology, Baystate Medical Center, Tufts University School of Medicine, Springfield, MA, USA.
authors.forename: Gabriel C
authors.initials: GC
authors.lastname: Caponetti
authors.forename: Liron
authors.initials: L
authors.lastname: Pantanowitz
authors.forename: Sharon
authors.initials: S
authors.lastname: Marconi
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Havens
authors.forename: Laura W
authors.initials: LW
authors.lastname: Lamps
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Otis
mesh_terms: D000293:Adolescent; D000328:Adult; D000942:Antigens, Bacterial / Q000032:analysis; D018416:Bartonella henselae / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D002372:Cat-Scratch Disease / Q000097:blood / Q000175:diagnosis* / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D007223:Infant; D008199:Lymphadenitis / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D012698:Serologic Tests; D016622:Silver Staining / Q000379:methods; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D004269:DNA, Bacterial