Distribution, organization, and ecology of bacteria in chronic wounds

TY - JOUR

T1 - Distribution, organization, and ecology of bacteria in chronic wounds

AU - Kirketerp-Møller, Klaus

AU - Jensen, Peter Østrup

AU - Fazli, Mustafa

AU - Madsen, Kit G

AU - Pedersen, Jette

AU - Moser, Claus

AU - Tolker-Nielsen, Tim

AU - Høiby, Niels

AU - Givskov, Michael

AU - Bjarnsholt, Thomas

N1 - Keywords: Ecosystem; Humans; In Situ Hybridization, Fluorescence; Pseudomonas Infections; Pseudomonas aeruginosa; Staphylococcal Skin Infections; Staphylococcus aureus; Wound Infection

PY - 2008/8/1

Y1 - 2008/8/1

N2 - Between 1 and 2% of the population in the developed world experiences a nonhealing or chronic wound characterized by an apparent arrest in a stage dominated by inflammatory processes. Lately, research groups have proposed that bacteria might be involved in and contribute to the lack of healing of these wounds. To investigate this, we collected and examined samples from chronic wounds obtained from 22 different patients, all selected because of suspicion of Pseudomonas aeruginosa colonization. These wound samples were investigated by standard culturing methods and peptide nucleic acid-based fluorescence in situ hybridization (PNA FISH) for direct identification of bacteria. By means of the culturing methods, Staphylococcus aureus was detected in the majority of the wounds, whereas P. aeruginosa was observed less frequently. In contrast, using PNA FISH, we found that a large fraction of the wounds contained P. aeruginosa. Furthermore, PNA FISH revealed the structural organization of bacteria in the samples. It appeared that P. aeruginosa aggregated as microcolonies imbedded in the matrix component alginate, which is a characteristic hallmark of the biofilm mode of growth. The present investigation suggests that bacteria present within these wounds tend to be aggregated in microcolonies imbedded in a self-produced matrix, characteristic of the biofilm mode of growth. Additionally, we must conclude that there exists no good correlation between bacteria detected by standard culturing methods and those detected by direct detection methods such as PNA FISH. This strongly supports the development of new diagnostic and treatment strategies for chronic wounds.

AB - Between 1 and 2% of the population in the developed world experiences a nonhealing or chronic wound characterized by an apparent arrest in a stage dominated by inflammatory processes. Lately, research groups have proposed that bacteria might be involved in and contribute to the lack of healing of these wounds. To investigate this, we collected and examined samples from chronic wounds obtained from 22 different patients, all selected because of suspicion of Pseudomonas aeruginosa colonization. These wound samples were investigated by standard culturing methods and peptide nucleic acid-based fluorescence in situ hybridization (PNA FISH) for direct identification of bacteria. By means of the culturing methods, Staphylococcus aureus was detected in the majority of the wounds, whereas P. aeruginosa was observed less frequently. In contrast, using PNA FISH, we found that a large fraction of the wounds contained P. aeruginosa. Furthermore, PNA FISH revealed the structural organization of bacteria in the samples. It appeared that P. aeruginosa aggregated as microcolonies imbedded in the matrix component alginate, which is a characteristic hallmark of the biofilm mode of growth. The present investigation suggests that bacteria present within these wounds tend to be aggregated in microcolonies imbedded in a self-produced matrix, characteristic of the biofilm mode of growth. Additionally, we must conclude that there exists no good correlation between bacteria detected by standard culturing methods and those detected by direct detection methods such as PNA FISH. This strongly supports the development of new diagnostic and treatment strategies for chronic wounds.

U2 - 10.1128/JCM.00501-08

DO - 10.1128/JCM.00501-08

M3 - Journal article

C2 - 18508940

SN - 0095-1137

VL - 46

SP - 2717

EP - 2722

JO - Journal of Clinical Microbiology

JF - Journal of Clinical Microbiology

IS - 8

ER -