title: Haematoxylin and eosin staining identifies medium to large bacterial aggregates with a reliable specificity: A comparative analysis of follicular bacterial aggregates in axillary biopsies using peptide nucleic acid-fluorescence in situ hybridization and haematoxylin and eosin staining.
abstract: Although peptide nucleic acid (PNA), fluorescence in situ hybridization (FISH) and confocal laser scanning microscopy (CLSM) are the reference tools in the study of bacterial aggregates/biofilms, it may also be rather time-consuming. This study aimed to investigate the sensitivity and specificity between bacterial aggregates identified by haematoxylin and eosin (HE) staining vs bacterial aggregates in corresponding PNA-FISH samples. Axillary biopsies were obtained in 24 healthy controls. HE-stained and PNA-FISH samples were investigated using traditional light microscopy and CLSM, respectively. The data demonstrate that HE staining identifies large bacterial aggregates (>10 μm) with a sensitivity of 0.43 and specificity of 1. The methods, however, are not equivalent as demonstrated by a McNemar's test (P=.04). Where bacterial aggregates >10 μm in diameter, HE staining may offer a rapid and practical low-cost tool to evaluate bacterial aggregates.
authors.affiliation: Department of Dermatology, Zealand University Hospital, Health Sciences Faculty, University of Copenhagen, Roskilde, Denmark.
authors.forename: Hans Christian
authors.identifier: 0000-0002-6145-5549
authors.initials: HC
authors.lastname: Ring
authors.affiliation: Department of Dermatology, Zealand University Hospital, Health Sciences Faculty, University of Copenhagen, Roskilde, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Theut Riis
authors.affiliation: Department of Immunology and Microbiology, Costerton Biofilm Centre, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Lene
authors.initials: L
authors.lastname: Bay
authors.affiliation: Department of Pathology, Zealand University Hospital, Health Sciences Faculty, University of Copenhagen, Roskilde, Denmark.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kallenbach
authors.affiliation: Department of Pathology, Zealand University Hospital, Health Sciences Faculty, University of Copenhagen, Roskilde, Denmark.|Department for Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bjarnsholt
authors.affiliation: Department of Dermatology, Zealand University Hospital, Health Sciences Faculty, University of Copenhagen, Roskilde, Denmark.
authors.forename: Gregor B E
authors.initials: GBE
authors.lastname: Jemec
mesh_terms: D001365:Axilla; D001419:Bacteria; D018407:Bacterial Physiological Phenomena; D001706:Biopsy; D004396:Coloring Agents; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018613:Microscopy, Confocal; D020135:Peptide Nucleic Acids; D012680:Sensitivity and Specificity; D012867:Skin / Q000382:microbiology* / Q000473:pathology*
chemical_list: D004396:Coloring Agents; D020135:Peptide Nucleic Acids; D004801:Eosine Yellowish-(YS); D006416:Hematoxylin
keywords: HE staining; PNA-FISH; bacterial aggregate; confocal laser scanning microscopy