Asymptomatic carriage of Clostridium difficile in an Irish continuing care institution for the elderly: prevalence and characteristics.
BACKGROUND
Clostridium difficile is an increasing cause of nosocomial diarrhoea and colitis. The aim of this study was to identify the prevalence and characteristics of asymptomatic C. difficile carriage in a continuing care institution for the elderly.


METHODS
Stool samples were collected from 100 asymptomatic patients, whose median age was 83 years. Samples were tested for C. difficile using traditional culturing methods, 16s rDNA and 16s-23s intergenic spacer (IGS) rDNA sequencing, and analysed for toxin production and toxin genes.


RESULTS
The prevalence of C. difficile carriage was 10/100 (10%) following culture and 16s and IGS sequencing. An additional seven isolates, initially identified as C. difficile, were subsequently identified by IGS rDNA sequencing as C. sordellii of the 10% that tested positive for C. difficile, seven tested positive for toxin A and B. A significant number of C. difficile carriers had recent antibiotic exposure compared with non-carriers, P = 0.046.


CONCLUSIONS
The prevalence of asymptomatic C. difficile carriage in this institution was 10%, 7% of which were toxin positive. This study underscores the importance of increased vigilance for C. difficile using microbial and molecular methodology and identifies patients at increased risk following antibiotic administration.
Ryan
J
J
4.31 Alimentary Pharmabiotic Centre, Biosciences Institute, University College Cork, College Road, Cork, Ireland.
Murphy
C
C
Twomey
C
C
Paul Ross
R
R
Rea
M C
MC
MacSharry
J
J
Sheil
B
B
Shanahan
F
F
D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000009:adverse effects / Q000627:therapeutic use; D001483:Base Sequence; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology / Q000635:transmission; D016360:Clostridioides difficile / Q000235:genetics / Q000302:isolation & purification*; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology / Q000635:transmission; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004197:Disease Reservoirs / Q000382:microbiology; D004761:Enterocolitis, Pseudomembranous / Q000453:epidemiology* / Q000382:microbiology / Q000473:pathology / Q000635:transmission; D004768:Enterotoxins; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D007902:Length of Stay; D008134:Long-Term Care / Q000706:statistics & numerical data; D008297:Male; D015995:Prevalence; D012307:Risk Factors
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D004768:Enterotoxins