Isolation of Clostridium difficile from the environment and contacts of patients with antibiotic-associated colitis

Application of a technique for serogrouping Clostridium difficile in an outbreak of antibiotic-associated diarrhoea

A severe outbreak of Clostridium difficile antibiotic-associated diarrhoea (AAD) in an orthopaedic surgical unit is reported. Thirty-seven cases and eight relapses were observed. The 45 related strains together with another 13 strains of C. difficile isolated during the same period in other wards of the same hospital were typed by detection of cytotoxin production, determination of sorbitol fermentation and serogrouping by agglutination with six rabbit antisera defining the serogroups A, B, C, D, F and G. All the strains from the outbreak belonged to serogroup C, were toxigenic and fermented sorbitol. In contrast, four different patterns were observed in seven isolates from cases of AAD in other wards. Finally, six strains isolated from four asymptomatic adults, one adult suffering from shigellosis and one child with salmonellosis demonstrated two patterns different from that of the epidemic isolates. The data strongly suggest nosocomial spread of this micro-organism.

Review of Clostridium difficile-associated diseases

Clostridium difficile has recently become recognized as an important nosocomial pathogen. This review summarizes what is known about the isolation of the organism, the spectrum of clinical disease, virulence factors, treatments, and methods of prevention. Risk factors for C. difficile disease are also discussed. The most important risk factor is the use of certain antibiotics (ampicillin, cephalosporins, and clindamycin). C. difficile is associated with 96% to 100% of cases of pseudomembraneous colitis, 60% to 75% of antibiotic-associated cases of colitis, and 11% to 33% of antibiotic-associated cases of diarrhea. Other risk factors include gastrointestinal manipulations, advanced age, female sex, inflammatory bowel disease, cancer chemotherapy, and renal disorders. Hospital outbreaks of C. difficile disease are examined. Data from nosocomial outbreaks support transmission of C. difficile by contaminated fomites and hand carriage by hospital personnel.

Significance of Clostridium difficile and its cytotoxin in children

Stools of 147 children belonging to different age groups were examined for the presence of Clostridium difficile, its cytotoxin and other enteric pathogens. None of the 31 full-term neonates, 5 (16%) of the 32 premature neonates, 27 (46%) of the 59 infants and 1 (4%) of the 25 older children excreted C. difficile in their stools. Faecal cytotoxin was only detected in four infants (7%). There was no correlation with diarrhoea, previous antibiotic therapy, type of diet, or the concomitant presence of other intestinal pathogens. We conclude that colonisation of the intestine by C. difficile is probably acquired from environmental sources and that it cannot be regarded as a significant cause of diarrhoea in children.

Method for the typing of Clostridium difficile based on polyacrylamide gel electrophoresis of [35S]methionine-labeled proteins

A typing method for Clostridium difficile based on the incorporation of [35S]methionine into cellular proteins, their separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their visualization by autoradiography is described. On analysis of the radiolabeled-protein profiles, nine distinct groups were observed (A to E and W to Z). The method, which is simple, reproducible, and readily expandable, has been applied in epidemiological studies to demonstrate cross-infection and hospital acquisition of C. difficile.

Diagnosis of Clostridium difficile-associated intestinal disease

Toxigenic Clostridium difficile is the major cause of antimicrobial agent-associated pseudomembranous colitis and is the etiological agent of approximately 30% of cases of nonspecific colitis and diarrhea (without colitis) induced by antimicrobial agents. In addition, C. difficile has been implicated in certain intestinal diseases not related to prior antimicrobial administration. C. difficile has been reported to be one of the most common enteropathogens isolated from stool specimens submitted to hospital laboratories. Thus, diagnosis of C. difficile-associated intestinal disease should now be routinely performed in diagnostic clinical laboratories. The diagnosis of C. difficile-associated intestinal disease relies on the demonstration of either the organism or the toxin(s) in stool specimens or antibody response in serum to the toxin(s). Several selective medium are available for the recovery of C. difficile from stool specimens. The toxin(s) of C. difficile can be demonstrated using a variety of techniques, including biological assays as well as immunological assays. This article will review the techniques currently available to aid in the diagnosis of C. difficile-associated intestinal disease.

Clostridium difficile-associated diarrhea follows perioperative prophylaxis with cefoxitin

Clostridium difficile-associated diarrhea during prolonged therapy of obstetric and gynecologic infections is known to occur with use of all classes of antibiotics except vancomycin and the aminoglycosides. We present 11 cases of C. difficile-associated diarrhea which followed a short course of perioperative prophylaxis with cefoxitin during a 1-year period. Nine of the cases of C. difficile-associated diarrhea were among 162 women who received cefoxitin perioperative prophylaxis for cesarean section or hysterectomy, but none occurred in 85 women who received one of four other antibiotics for perioperative prophylaxis (p = 0.024, Fisher's exact test). The two other occurrences of C. difficile-associated diarrhea following perioperative prophylaxis with cefoxitin were in women who underwent exploratory laparotomy. We conclude that C. difficile-associated diarrhea is related to perioperative prophylaxis with cefoxitin.

Prevention of cecitis in hamsters by certain prostaglandins

Acute inflammation of the colon (cecitis) was produced in hamsters by daily subcutaneous administration of an antibiotic for 3 days. The following prostaglandins completely prevented the cecitis: 16,16-dimethyl-PGE2, 15(R)-15-methyl-PGE2, and 2-acetyl-2-decarboxy-15(S)-15-methyl-PGF2 alpha. PGF2 beta was less active. The synthesis of 2-acetyl-2-decarboxy-15(S)-methyl-PGF2 alpha is described. Castor oil also prevented the cecitis and peanut oil exerted partial protection. Since these oils contain linoleic acid, a precursor of PGE1, protection may have been due to endogenous formation of that prostaglandin. A partial block of the protective effect of castor oil by treatment with indomethacin supports such mechanism. The tissue level of endogenous prostaglandins seems to exert protection since administration of cyclooxygenase inhibitors, indomethacin and aspirin, markedly increased the incidence of cecitis. Magnesium sulfate given orally and sodium salicylate given subcutaneously reduced the incidence of cecitis only partially. The following agents were inactive: loperamide, an antidiarrheic agent; carbachol, a cholinergic and diarrheogenic agent, atropine, an anticholinergic agent; and acetazolamide, a carbonic anhydrase inhibitor. These results, show that certain prostaglandins, which have been shown earlier to be cytoprotective for the stomach and the small intestine, are cytoprotective for the large intestine as well.

Effect of adding sodium taurocholate to selective media on the recovery of Clostridium difficile from environmental surfaces

The recovery of Clostridium difficile on a medium containing cefoxitin, cycloserine, fructose, and egg yolk was compared with that on media containing one of three preparations of sodium taurocholate. In aerobic environments contaminated with C. difficile, media containing either crude taurocholate from Mann Research Laboratories, New York, N.Y., or pure taurocholate from Sigma Chemical Co., St. Louis, Mo., recovered organisms significantly more often than did cefoxitin-cycloserine-fructose-egg yolk agar.

Serogrouping of Clostridium difficile strains by slide agglutination

Six different agglutinating antisera were obtained by immunizing rabbits with Formol-treated strains of Clostridium difficile. After appropriate absorption, these antisera were used to define six serogroups designated by the letters A, B, C, D, F, and G. Altogether, 315 strains of C. difficile from various origins were tested for slide agglutination by these antisera; 312 (99%) of them were agglutinated by one of these antisera. A and C were the most common serogroups. An excellent correlation, ranging from 85 to 100%, was found between the serogroup and the toxigenicity of the strains. The correlation between serogroup and sorbitol fermentation was higher, ranging from 89 to 100%. The results of this typing were compared with the clinical origin of the strains. Only strains of serogroups A, C, and D were isolated in 153 cases of antibiotic-associated diarrhea. This series included strains from three outbreaks; all the strains in two of the outbreaks belonged to serogroup C, and in the third, all the strains belonged to serogroup A. Strains of serogroups B, F, and G were only found in the stools of asymptomatic neonates or young children. In the latter samples, strains of serogroups A and D were found in the same ratio as in adults with antibiotic-associated diarrhea, but strains of serogroup C were seldom isolated. In patients treated with antineoplastic drugs and suffering from diarrhea, the distribution of the strains was the same as in cases of antibiotic-associated diarrhea.

Germinability and heat resistance of spores of Clostridium difficile strains

Out of 111 Clostridium difficile strains, 108 produced spores in numbers of more than 10(5)/ml and the remaining three did not produce any spores in brain heart infusion medium. The germination frequency in the medium without lysozyme varied widely from strain to strain, ranging from less than 10(-8) to 10(0), and in 77 of the 108 strains the germination frequency was 10(-5) or less. The spores, when treated with sodium thioglycollate and then inoculated into the medium containing lysozyme, germinated in all of the 108 strains at a frequency of 10(-0.5) or more. The spores of two strains germinated at a frequency of more than 10(-0.5) in all methods. Spores of C. difficile strains were fairly highly heat-resistant; D100C values ranged from 2.5 to 33.5 min.

Typing scheme for Clostridium difficile: its application in clinical and epidemiological studies

Epidemiological studies of Clostridium difficile diarrhoeal disease have been hindered by the lack of a typing scheme for this organism. A typing method based on the incorporation of sulphur-35-labelled methionine into cellular proteins and their separation by sodium dodecylsulphate/polyacrylamide gel electrophoresis showed clear pattern differences between strains, and nine distinct groups within the C difficile species were established. 98% of 250 clinical strains derived from four hospitals were typable. Group X was the commonest group and was associated with outbreaks of pseudomembranous colitis and antibiotic-associated colitis in two hospitals. Groups A-D were isolated predominantly from mothers and newborn infants. In outbreaks of antibiotic-associated colitis in oncology and orthopaedic wards the same strains, group X and group E, respectively, were isolated from patients and their environment, providing strong evidence of cross-infection between patients and of hospital acquisition of C difficile.

Clostridium difficile-associated diarrhoea

During the course of 1 year, Clostridium difficile was isolated from 145 (4 per cent) of 3591 faecal specimens submitted to a hospital routine bacteriology laboratory. These C. difficile positive specimens came from 95 patients or 10.99 per cent of 864 patients investigated for suspected gastroenteritis. In a control population of 318 persons C. difficile was isolated from only 10 of them or 3.1 per cent; this difference was statistically significant. We conclude that as this increase in the isolation of C. difficile from patients with diarrhoea is significant and is about as frequent as that of Campylobacter spp., faecal specimens submitted for routine bacteriology should also be cultured for C. difficile . As with diarrhoea caused by other enteric pathogens, most C. difficile -associated episodes of diarrhoea are mild and spontaneously reversible but approximately 20 per cent of patients have prolonged diarrhoea and may benefit from treatment.

Clostridium difficile colitis associated with the use of antineoplastic agents

Eight patients are presented in whom treatment with antineoplastic agents, in particular the folic acid antagonist methotrexate, precipitated Clostridium difficile-related diarrhoea and pseudomembranous colitis. The clinical presentation of these patients was identical to that encountered in patients developing antibiotic associated diarrhoea and colitis. Clostridium difficile-related diarrhoea and colitis should be suspected in any patient developing diarrhoea during the course of anti-neoplastic chemotherapy or within three weeks of its cessation. This complication is effectively treated with oral vancomycin.

Incidence and origin of Clostridium difficile in neonates

The stools of 65 of 92 (71%) infants in a special care nursery yielded Clostridium difficile on culture. Ninety percent of stools collected after 6 to 35 days in the unit were positive, and 36% of these also contained toxin. When tested in vitro, 94% of the isolates produced toxin. Of 110 swabs collected from the environment of the unit, 9% were positive for C. difficile, but the stools of 12 nurses working on the unit were negative. Thirty-five vaginal swabs collected from mothers just before delivery were negative for C. difficile on culture, but 16 of their infants had C. difficile in their stools. It was concluded that there is a high carriage rate in the stools of neonates of C. difficile acquired progressively during the course of their stay in the special care unit. Infection is mainly from environmental sources rather than maternal transmission.

[Clostridium difficile and antibiotic-associated colitis in risk patients: 2-month epidemiologic study in an intensive care unit]

A toxin produced by Clostridium difficile has been implicated in the pathogenesis of antibiotic-associated colitis. It is not known how often the microorganism is encountered in Germany particularly in high risk patients. Therefore, following a lethal case of colitis, stool samples of 90 patients and 30 staff members of an intensive care unit were screened routinely for C. difficile over 2 months. The organism was found in 6 of 41 patients treated with antibiotics (14.6%); four of them apparently acquired C. difficile while in hospital whereas in 2 a pre-existing carrier state could not be excluded. Colitis developed in 3 of the 6 patients as judged from endoscopy or a positive cytotoxin assay; in 2 patients (not subjected to endoscopy) colitis was suspected on clinical grounds, and 1 patient became an asymptomatic carrier. C. difficile was not found in 49 patients without antibiotic medication, in the health personal and in 12 patients of a general ward. Patients harbouring C. difficile were clustered in certain bed sites of the unit. Environmental studies recovered the microorganism from bed pan washing machines of bedridden and from toilets of ambulant patients but not from other sites like the hands of the personal. These results suggest that chronic carriers of C. difficile, as far as they are identified by current bacteriological methods, are rare in Germany (not more than 2 out of 132 persons investigated, i.e. 1.5%). The frequent finding of C. difficile in patients treated in certain bed sites supports the view that the infection may be acquired from exogenous sources. Antibiotic-associated colitis should be considered more often when intensive care patients are treated with antibiotics.

Pseudomembranous colitis associated with changes in an ileal conduit

A case of antibiotic associated pseudomembranous colitis following total cystectomy is reported, in which there was involvement of the ileal conduit. The small bowel remaining in situ was uninvolved. Bacteriological studies revealed Clostridium difficile and the toxin in both colon and ileal conduit. Relevant publications concerning pathogenesis are discussed, in relation to the unusual site described in this case. Epidemiological evidence is reviewed which suggests that isolation of patients with pseudomembranous colitis is a logical course of action.

Comparison of methods for recovery of Clostridium difficile from an environmental surface

Survival of Clostridium difficile in an aerobic environment is possible because of spore formation. When sodium taurocholate is substituted for the egg yolk of a selective medium, cycloserine-cefoxitin-fructose-agar (CCFA), enhanced recovery of C. difficile spores is shown. This selective medium (TCCFA) does not improve recovery of vegetative forms. In this study, dry and saline-moistened swabs, adhesive paddles, and Rodac plates containing CCFA and TCCFA were compared in their ability to recover C. difficile spores from an inoculated surface. Rodac plates grew 20 to 25 times as many spores on TCCFA as on CCFA. Saline-moistened swabs recovered fewer organisms than Rodac plates. Dry swabs and adhesive paddles rarely recovered spores. Prereduction of agar in an anaerobic chamber was not necessary for optimal spore recovery. Optimal growth of vegetative C. difficile required prereduced media. Agar prereduced for 2 h supported the growth of 12 C. difficile isolates as well as agar prereduced for 18 h. Vegetative cells of C. difficile survived for only 15 min in room air. Use of Rodac plates containing TCCFA is preferred for detection of C. difficile spores in the hospital environment.

Clostridium difficile toxin associated with chronic diarrhea and failure to gain weight

Two young children are described in whom chronic diarrhea associated with the presence of Clostridium difficile toxin responded to treatment with oral vancomycin. C. difficile infection should be considered in the evaluation of young children with diarrhea who fail to gain weight, even in the absence of prior antibiotic treatment.

Bacteriophage and bacteriocin typing scheme for Clostridium difficile

The study of the epidemiology of infection with Clostridium difficile would be aided by a way to type individual bacterial isolates. We therefore sought bacteriophages for use in typing. With mitomycin C exposure (3 micrograms/ml), filtrates from 10 strains of C. difficile had plaque-forming lytic activity on other C. difficile strains. Individual phage were passaged and made into high-titer stock preparations for typing. Electron microscopy revealed tailed phage particles from one such preparation. In addition to phage, inhibitory activity without distinct plaque formation consistent with bacteriocins was observed for 20 strains. C. difficile isolates from 16 patients taken 1 to 14 days apart were similar in their phage sensitivity pattern, whereas isolates from separate geographic locations showed a great variety of patterns. We conclude that bacteriophage should be useful for typing strains of C. difficile.

Relapse of antibiotic associated colitis: endogenous persistence of Clostridium difficile during vancomycin therapy

This study reports 24 patients with antibiotic associated colitis due to Clostridium difficile. Fifteen patients were treated with vancomycin due to the severity of the colitis and in eight of these a clinical relapse of the colitis occurred after vancomycin therapy was stopped. Bacteriological investigations of these patients indicated that C difficile was able to persist in stool samples during vancomycin therapy in the absence of detectable cytotoxin. This was in contrast with the seven patients successfully treated with vancomycin without relapse, and those not treated with vancomycin where both stool cultures and cytotoxin assays became negative. These results suggest that patients being treated with vancomycin for antibiotic associated colitis due to C difficile should have stool cultures done during and after treatment. Persistence of the organism in the absence of detectable cytotoxin may identify those patients who relapse and lead to either recommencement of vancomycin or alternative therapeutic approaches.

Outbreaks of diarrhea associated with Clostridium difficile and its toxin in day-care centers: evidence of person-to-person spread

Clostridium difficile was associated with five outbreaks of diarrhea occurring in three day-care centers caring for children less than 2 years of age during a three and one-half-month period; two centers had one outbreak of diarrhea, and one had three outbreaks. The frequency of isolation of C. difficile and its toxin was determined in stool specimens from 65 children attending the three day-care centers. Twelve of 21 (57%) children who had diarrhea excreted C. difficile and its toxin, whereas only four of 44 (9%) children who did not experience diarrhea yielded the organism and the toxin. Five of the 12 symptomatic children with C. difficile and its toxin had received prior antimicrobial therapy for upper respiratory tract infections. An eight-month prospective study was then carried out in one room of the center where the three outbreaks had occurred. Initially, one child had culture-positive stools for C. difficile. During the first 13-week study period six additional children of the 12 (50%) in the room under study became colonized with C. difficile. Six of the seven children who excreted C. difficile and its toxin experienced diarrhea with C. difficile toxin-positive stools by the end of the 13 weeks. Environmental contamination increased as more children became colonized and developed diarrhea. Electrophoretic evaluation of environmental and stool isolates obtained during one outbreak of diarrhea showed that the isolates had an identical protein pattern. Findings of this study indicate the importance of searching for C. difficile in children in day-care centers who develop diarrhea.

Isolation of Clostridium difficile from patients and the environment of hospital wards

Rectal swabs from 122 patients and 497 environmental swabs from several wards were examined for the presence of Clostridium difficile in order to assess the role of the environment in the spread of this organism. Clostridium difficile was isolated from 6/27 (22.2%) oncology patients and from 8/163 (4.9%) environmental specimens obtained from the oncology unit. Items found positive for C difficile were those subjected to faecal contamination such as commode chairs, bed pans, dust pans, discard bins, the sluice and a disposable bed pan machine. Fourteen of 51 (27.4%) asymptomatic neonates yielded mostly toxigenic C difficile in their stools during their first week of life. Five of 156 (3.2%) specimens taken from inanimate objects in the environment of the neonatal units were positive for C difficile. The organism was also isolated from the hands of a nurse. Similar antibiogram patterns were demonstrated in the strains obtained from the patients and their environment indicating the possible occurrence of cross infection. These results indicate that environmental contamination is important in the spread of C difficile in hospitalised patients and the implementation of isolation procedures may limit that spread.

Investigation of an outbreak of antibiotic-associated colitis by various typing methods

During an outbreak of diarrheal disease due to Clostridium difficile in a surgical ward, 16 C. difficile isolates were cultured from fecal samples of 15 patients. Agarose gel electrophoresis for the detection of plasmid DNA, crossed immunoelectrophoresis for the detection of extracellular antigens and toxins, polyacrylamide gel electrophoresis for analyses of soluble proteins, assays for cytotoxicity, and a comparison of susceptibility to antimicrobial agents were employed. At least 12 of the 16 isolates were shown to be phenotypically the same strain. These findings suggest that in a hospital setting, diarrhea and pseudomembranous colitis caused by C. difficile can be of nosocomial origin and that they can spread from patient to patient.

Clostridium difficile toxin in asymptomatic neonates

Clostridium difficile toxin was detected in the feces of 10.5% of normal newborn infants and 55% of neonates in the intensive care unit. None of the normal infants and less than one-third of those in the NICU had any signs of enteric illness. Vaginal delivery and breast-feeding were associated with increased rates of toxin carriage. Although toxin was not detected during antibiotic therapy, it could be found in 85% of infants two weeks or more, and for at least an additional two months, following exposure to antibiotics.

The prevalence of Clostridium difficile and toxin in a nursery population: a comparison between patients with necrotizing enterocolitis and an asymptomatic group

During a period when certain neonates in our nursery developed necrotizing enterocolitis, we studied stool specimens from a population of symptomatic and asymptomatic patients for the presence of Clostridium difficile and its toxin. The presence of the organism among nursery personnel and in the nursery environment was also evaluated. Results showed that five symptomatic neonates and 17 asymptomatic neonates in a population of 37 patients studied in our neonatal intensive care and intermediate care nurseries had positive stool cultures for C. difficile. Toxin was detected in stool from four of five symptomatic patients and was present at dilutions of greater than 1/125 in stool from six asymptomatic patients who were culture positive for C difficile. The organism was not found in stool samples from any nursery personnel but was recovered from the hand culture of a nursery worker and from the inanimate environment. Although our findings support the notion of nosocomial spread of C difficile, we were unable to clearly implicate the organism as the cause of necrotizing enterocolitis in our nursery.

Clostridium difficile in association with sporadic diarrhoea

A total of 154 patients admitted to an infectious diseases unit were included in a year's prospective survey of sporadic diarrhoeal disease. Stools from 19 of them yielded Clostridium difficile, generally on more than one occasion. Twelve of these patients were assessed as having a severe or moderately severe gastrointestinal illness: Cl difficile was the only pathogen isolated from 10 of them, and two had an associated salmonella infection. Seven had had a recent course of antibiotics, but five had not taken antibiotics. Faeces from seven patients with moderate or mild gastrointestinal illness yielded Cl difficile, and two of these patients also had an associated salmonella infection. Two patients in this group had no antibiotic history. From these findings, the occurrence of C difficile in faeces could not be described as antibiotic-associated. Faecal Cl difficile cytotoxin was detected in only six patients, and generally at low levels. In such patients a more relevant pathogenic index might take account of the numbers of Cl difficile present and of their toxigenic potential.

Production of antitoxins to two toxins of Clostridium difficile and immunological comparison of the toxins by cross-neutralization studies

We prepared antitoxins specific for each of two toxins of Clostridium difficile and used these to demonstrate that the toxins are immunologically distinct.