title: Evaluation of postmortem bacterial migration using culturing and real-time quantitative PCR.
abstract: Postmortem bacteriology can be a valuable tool for evaluating deaths due to bacterial infection or for researching the involvement of bacteria in various diseases. In this study, time-dependent postmortem bacterial migration into liver, mesenteric lymph node, pericardial fluid, portal, and peripheral vein was analyzed in 33 autopsy cases by bacterial culturing and real-time quantitative polymerase chain reaction (RT-qPCR). None suffered or died from bacterial infection. According to culturing, pericardial fluid and liver were the most sterile samples up to 5 days postmortem. In these samples, multigrowth and staphylococci were not or rarely detected. RT-qPCR was more sensitive and showed higher bacterial positivity in all samples. Relative amounts of intestinal bacterial DNA (bifidobacteria, bacteroides, enterobacter, clostridia) increased with time. Sterility of blood samples was low during the studied time periods (1-7 days). The best postmortem microbiological sampling sites were pericardial fluid and liver up to 5 days after death.
authors.affiliation: School of Medicine, University of Tampere, Tampere, Finland. Sari.Tuomisto@uta.fi
authors.forename: Sari
authors.initials: S
authors.lastname: Tuomisto
authors.forename: Pekka J
authors.initials: PJ
authors.lastname: Karhunen
authors.forename: Risto
authors.initials: R
authors.lastname: Vuento
authors.forename: Janne
authors.initials: J
authors.lastname: Aittoniemi
authors.forename: Tanja
authors.initials: T
authors.lastname: Pessi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification; D018407:Bacterial Physiological Phenomena; D001431:Bacteriological Techniques; D001769:Blood / Q000382:microbiology; D004269:DNA, Bacterial / Q000032:analysis*; D006801:Humans; D008099:Liver / Q000382:microbiology; D008198:Lymph Nodes / Q000382:microbiology; D008297:Male; D008643:Mesentery / Q000382:microbiology; D008875:Middle Aged; D010496:Pericardium / Q000382:microbiology; D011180:Postmortem Changes; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D004269:DNA, Bacterial
keywords: bacterial culturing; forensic science; postmortem microbiology; real-time quantitative polymerase chain reaction; sample reliability; sampling place