Journal List > Korean J Leg Med > v.41(4) > 1088024

Na, Park, Kim, and Park: Bacteria as Normal Flora in Postmortem Body Fluid Samples

Abstract

Bacterial culture and identification are both useful in the clinical and forensic fields, although the postmortem changes in human microbiology are poorly understood. This study aimed to identify bacteria that were considered normal flora in postmortem body fluid samples. Bacterial culture and identification testing were performed for 336 body fluid samples (e.g., cardiac blood, peripheral blood, pericardial fluid, pleural fluid, peritoneal fluid, cerebrospinal fluid, and urine) from 129 forensic autopsy cases. Bacteria were identified using both genetic and biochemical methods, and testing for C-reactive protein (CRP) was used to identify the presence of antemortem inflammation. Among the 129 autopsy cases, 79 cases (69.3%) were negative for CRP, and bacterial culture and identification testing were performed for 185 samples from those 79 cases. Bacteria that were considered both normal flora and pathogens were identified in the CRP-negative cases. Therefore, the results from postmortem bacterial culture and identification testing should be interpreted in the context of other postmortem examination, including CRP testing. Furthermore, case selection, postmortem testing, and interpretations of the results should be performed by both clinical bacteriologists and forensic pathologists. To best of our knowledge, this is the first study to examine normal flora in various postmortem body fluid samples form Korean autopsy cases.

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Table 1.
General characteristics of the cases and samples
Characteristic No.
Sex 129
Male 88
Female 41
Age, mean (range, yr) 50.9 (0-111)
Cases 129
Positive CRP cases 35
Negative CRP cases 79
Not tested for CRP 15
Samples 336
In positive CRP cases 151
In negative CRP cases 185
Cardiac blood 71
Peripheral blood 5
Pericardial fluid 41
Pleural fluid 27
Peritoneal fluid 15
Cerebrospinal fluid 18
Urine 3
Miscellaneous 5

CRP, C-reactive protein.

Table 2.
Representative postmortem bacteria in cases that were negative for C-reactive protein
  Cardiac blood Pericardial fluid Pleural fluid Peritoneal fluid Cerebrospinal fluid Urine
By genetic method Acinetobacter spp. Acinetobacter spp. Aeromonas spp. Citrobacter spp. Aeromonas spp. Acinetobacter spp.
  Aeromonas spp. Aeromonas spp. Aeromonas hydrophila Citrobacter freundii Comamonas spp. Pseudomonas spp.
  Citrobacter spp. Aeromonas hydrophila Aeromonas veronii Clostridium spp. Enterobacter spp.  
  Citrobacter freundii Citrobacter spp. Citrobacter spp. Enterobacter spp. Escherichia spp.  
  Escherichia spp. Citrobacter freundii Citrobacter freundii   Lactococcus spp.  
  Escherichia coli Enterobacter spp. Citobacter braakii   Proteus spp.  
  Enterococcus spp. Enterobacter cancerogenus klebsiella spp.   Pseudomonas spp.  
  Enterococcus faecalis Leuconostoc spp. klebsiella pneumoniae   Serratia spp.  
  Klebsiella spp. Leuconostoc lactis Proteus spp.   Vibrio spp.  
  Klebsiella pneumoniae Pseudomonas spp. Proteus hauseri      
  Lactococcus spp. Pseudomonas monteilii Pseudomonas spp.      
  Lactococcus lactis Pseudomonas fulva Raoultella spp.      
  Proteus spp. Staphylococcus spp. Shewanella spp.      
  Proteus hauseri Staphylococcus aureus Shewanella algae      
  Pseudomonas spp. Staphylococcus epidermidis Vibrio spp.      
  Pseudomonas monteilii          
  Pseudomonas fulva          
  Staphylococcus spp.          
  Streptococcus spp.          
  Streptococcus agalactiae          
  Vibrio spp.          
By biochemical method Acinetobacter spp. Acinetobacter spp. Aeromonas spp. Acinetobacter spp. Aeromonas spp. Enterobacter spp.
  Aeromonas spp. Acinetobacter baumannii Chryseobacterium spp. Citrobacter spp. Enterobacter spp. Lactobacillus spp.
  Bacillus spp. Acinetobacter junii Chryseobacterium indologenes Enterobacter spp. Enterobacter aerogenes Pseudomonas spp.
  Citrobacter spp. Aeromonas spp. Citrobacter spp. Enterococcus spp. Lactococcus spp. Streptococcus spp.
  Citrobacter sordellii Aeromonas hydrophila Citrobacter freundii Escherichia spp. Lactococcus lactis  
  Escherichia spp. Aeromonas sobria Enterococcus spp. Escherichia coli Staphylococcus spp.  
  Escherichia coli Bacillus spp. Escherichia spp. Morganella spp. Staphylococcus capitis  
  Escherichia hermannii Bacillus pumilus Escherichia coli Morganella morganii Staphylococcus epidermidis  
  Enterobacter spp. Citrobacter spp. Klebsiella spp. Staphylococcus spp. Vibrio spp.  
  Enterobacter aerogenes Citrobacter freundii Klebsiella pneumoniae Streptococcus spp. Vibrio parahaemolyticus  
  Enterobacter cloacae Enterobacter spp. Lactobacillus spp.      
  Enterococcus spp. Enterobacter aerogenes Lactococcus spp.      
  Enterococcus faecalis Enterococcus spp. Lactococcus lactis      
  Enterococcus casseliflavus Enterococcus faecalis Proteus spp.      
  Klebsiella spp. Escherichia spp. Proteus penneri      
  Klebsiella pneumoniae Escherichia coli Proteus vulgaris      
  Lactobacillus spp. Escherichia hermannii Pseudomonas spp.      
  Lactococcus spp. Klebsiella spp. Pseudomonas putida      
  Lactococcus lactis Lactobacillus spp. Shewanella spp.      
  Proteus spp. Lactobacillus fermentum Shewanella algae      
  Proteus vulgaris Lactococcus spp. Shewanella putrefaciens      
  Pseudomonas spp. Lactococcus lactis Streptocossus spp.      
  Pseudomonas putida Pantoea spp. Streptococcus mitis      
  Staphylococcus spp. Photobacterium spp. Streptococcus salivarius      
  Staphylococcus capitis Photobacterium damselae Vibrio spp.      
  Streptococcus spp. Proteus spp.        
  Streptococcus mitis Proteus vulgaris        
  Streptococcus salivarius Pseudomonas spp.        
  Vibrio spp. Pseudomonas putida        
  Staphylococcus spp.          
  Staphylococcus xylosus Staphylococcus epidermidis          
  Stenotrophomonas spp.          
  Streptococcus spp.          
  Streptococcus mitis          
  Streptococcus parasanguinis          
  Streptococcus salivarius          
  Streptococcus agalactiae          
  Vibrio spp.          
  Vibrio parahaemolyticus          
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