Journal of Infection (1998) 36, 287-288
Community-acquired Clostridium difficile infection L. Kyne .I, C. Merry 2, B. O'Connell 2, C. Keane 2 and D. O'Neill 1 1Department of Medicine for the Elderly, St. lames's Hospital, James's Street, Dublin 8, Ireland, and 2Department of Mircobiology, St. James's Hospital, lames's Street, Dublin 8, Ireland Clostridium difficile-associated disease (CDAD) is primarily a nosocomial condition, Community-acquired disease has been reported but the incidence is felt to be low and the rate of disease resulting in hospitalization is reported as negligible. We recently experienced a 6-month outbreak of CDAD (January to June 1995): 139 patients were involved and four deaths were attributable to pseudomembranous colitis. Early in the outbreak period we were aware that many new admissions presented with C. difficile cytotoxin B positive diarrhoea: in some cases this was the sole reason for hospitalization. This observation forms the basis of this report.
Patients, Methods and Results St. James's hospital is a 700-bed university teaching hospital. It is a tertiary referral centre and serves a population of approximately 2 50 000 people. From January to April 1995 all new cases of CDAD were reviewed. All cases had diarrhoea in association with a positive stool cytotoxin test for Clostridium difficile. The following information was recorded: demographic data, diagnosis, previous hospitalizations and prior antimicrobial therapy. Isolates were typed using pyrolysis mass spectrometry (PMS). Community-acquired disease was defined as C. difficile-associated diarrhoea occurring on or within 72 h of admission, in the absence of hospitalization in the previous 60 d a y s ] Seventy-three cases were identified: 15 (20.6%) had CDAD on admission; seven (9.6%) of these had been hospitalized within the previous 60 days (four in St. James's hospital; three in other hospitals) and eight (11%) cases were community-acquired (Table I). The remaining 58 (79.4%) cases were hospital-acquired. All communityacquired cases had diarrhoea, defined as three or more loose bowel motions for at least 2 days, in association with a positive stool cytotoxin test for C. difficile. Other possible causes for diarrhoea, including medications and chronic gastrointestinal conditions, were excluded. Stools were examined and tested negative for ova, cysts, parasites and other enteric pathogens including Salmonella, Shigella and Campylobacter jejuni. PMS identified two predominant strains (1 and 2) which were responsible * Address all correspondenceto: L. Kyne,ResearchFellow, Gerontology Division, Beth Israel Deaconess Medical Center (East Campus), 330 Brookline Avenue, Boston, MA 02215, U.S.A. Accepted for publication 7 August, 1997. 0163-4453/98/030287 + 02 $12.00/0
for the hospital outbreak and isolated in almost 75% of samples tested. The group 1 strain was isolated in the faeces of two patients with community-acquired infection. Isolates submitted from one patient transferred from another Dublin hospital and from eight patients in three associated Dublin hospitals also tested positive for this strain.
Comment The isolation of one of the outbreak strains in two new admissions without prior hospitalization suggests that there may have been a link between the hospital outbreak and the community. Further support for this comes from identification of this strain in isolates from four other Dublin hospitals. Although the latter may represent intrahospital transfer of patients, or readmission of colonized patients to other hospitals, direct evidence for this is lacking and was only documented in one case. These results suggest that there may be a significant reservoir of toxigenic C. difficile in the community or that the hospital outbreak reflected a large but unrecognized outbreak of disease in this setting. However, the latter is speculation only, as testing of non-hospitalized community cases of diarrhoea for C. difficile was not possible. Another element may be that a co-factor (for example, an u n k n o w n viral or toxic agent) was responsible for the simultaneous presence of two epidemic strains in the hospital plus an increase in the incidence of communityacquired disease (two cases of which were not associated with prior antimicrobial therapy). The epidemiology of community-acquired CDAD is unclear. 2 In a recent study, Riley et al. suggested that the © 1998 The British Infection Society
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Table I. Patients with symptomatic C, difficile infection admitted from the community. Case
1 2 3 4 5 6 7 8
Age
25 84 59 62 67 46 89 76
Reason for admission
Recent hospitalization
Recent antibiotics
Duration of diarrhoea pre-admission
C. difficile
Diarrhoea COAl) Diarrhoea Abdo pain Chest pain Hepatitis A COAD COAD
No No No No No No No No
Flucloxacillin Co-amoxiclav None None Not known Ampicillin Co-amoxiclav Amoxycillin
10 3 9 5 3 6 1 1
NA 1 Distinct NA 1 Distinct NA Distinct
days days days days days days day day
strain
COAD = chronic obstructive airways disease; NA = not available.
incidence m a y be underestimated: this in part m a y be due to a lack of awareness and investigation of this organism as a cause of community-acquired diarrhoea by doctors. 3 Following the distribution of educational material to GPs, the isolation rate of this organism rose from 2.6% to 10.7°/o. 3 Hospital-based studies have demonstrated that almost 20% of C. difficile culture positive patients harboured the organism on admission; however, in these studies few of these patients were symptomatic) This is the first description of a large outbreak in which a significant proportion of cases had symptomatic C. difficile infection on admission. In light of these findings, we believe that CDAD is a problem which is not confined to hospitals. Communityacquired disease m a y be related to the increasing incidence of nosocomial CDAD, or the more widespread use of broad spectrum antibiotics in general practice) We recommend that C. difficile should be considered
as a cause of diarrhoea in both settings and that all symptomatic new admissions should be screened for its presence.
References 1 Samore M, Bettin, Degirolami PC, Clabots CR, Gerding DN, Karchmer AW. Wide diversity of Clostridium difficile types at a tertiary referral hospital, l Infect Dis 1994; 170: 615-621. 2 Hirschhorn LR, Trnka Y, Onderdonk A, Lee ML, Plait R. Epidemiology of community-acquired Clostridium difficile-associated diarrhoea. J lnfect Dis 1994; 169: 127-133. 3 Riley TV, Cooper M, Bell B, Golledge CL. Community acquired Clostridium difficile-associated diarrhea. Clin lnfec Dis 1995; 20(Suppl. 2): $263-$265. 4 Clabots CR, Johnson S, Olson MM, Peterson LR, Gerding DN, Acquisition of Clostridium difficile by hospitalized patients; evidence for colonized new admissions as a source of infection. ] lnfect Dis 1992; 166: 561-567. 5 Davey PG, Bax RP, Newey J e t al. Growth in the use of antibiotics in the community in England and Scotland in 1980-93. BM] 1996; 312: 613.