Treatment of Clostridium perfringens enterotoxin-associated diarrhoea with metronidazole

Type IV pili and the CcpA protein are needed for maximal biofilm formation by the gram-positive anaerobic pathogen Clostridium perfringens

The predominant organizational state of bacteria in nature is biofilms. Biofilms have been shown to increase bacterial resistance to a variety of stresses. We demonstrate for the first time that the anaerobic gram-positive pathogen Clostridium perfringens forms biofilms. At the same concentration of glucose in the medium, optimal biofilm formation depended on a functional CcpA protein. While the ratio of biofilm to planktonic growth was higher in the wild type than in a ccpA mutant strain in middle to late stages of biofilm development, the bacteria shifted from a predominantly biofilm state to planktonic growth as the concentration of glucose in the medium increased in a CcpA-independent manner. As is the case in some gram-negative bacteria, type IV pilus (TFP)-dependent gliding motility was necessary for efficient biofilm formation, as demonstrated by laser confocal and electron microscopy. However, TFP were not associated with the bacteria in the biofilm but with the extracellular matrix. Biofilms afforded C. perfringens protection from environmental stress, including exposure to atmospheric oxygen for 6 h and 24 h and to 10 mM H(2)O(2) for 5 min. Biofilm cells also showed 5- to 15-fold-increased survival over planktonic cells after exposure to 20 microg/ml (27 times the MIC) of penicillin G for 6 h and 24 h, respectively. These results indicate C. perfringens biofilms play an important role in the persistence of the bacteria in response to environmental stress and that they may be a factor in diseases, such as antibiotic-associated diarrhea and gas gangrene, that are caused by C. perfringens.

Clostridium perfringens toxin genotypes in the feces of healthy North Americans

We investigated the frequency of Clostridium perfringens in the normal fecal flora of healthy North Americans. About half of 43 subjects were colonized with C. perfringens at levels of approximately 10(6)cfu/g feces. Only type A strains were recovered. Spores sometimes outnumbered vegetative cells. Several genotypes were found. Some donors carried two genotypes, some only one. We found no alpha, beta2 or enterotoxin in the stools of any donors. Though some isolates carried toxin genes (e.g. cpe and cpb2) on plasmids, we saw no indication that healthy humans are the reservoir for the chromosomally-borne cpe recovered from cases of C. perfringens food poisoning.

Laboratory diagnosis of antibiotic-associated diarrhea: a Polish pilot study into the clinical relevance of Clostridium difficile and Clostridium perfringens toxins

In the present study, we investigated the prevalence of the Clostridium perfringens enterotoxin (CPEnt) in stool samples originally submitted for detection of Clostridium difficile toxins. Fifty-two fecal samples from inpatients were screened simultaneously for C. difficile and C. perfringens toxins: 75% of the specimens were positive for TcdA/TcdB toxins, 40% were positive for CPEnt, and 31% gave positive test results for both. It is interesting to note that only a relatively small number of C. perfringens isolates were positive for the cpe gene. All C. difficile strains were susceptible to metronidazole, but intermediate metronidazole resistance was documented for the C. perfringens isolates, which decreased upon in vitro passaging in the absence of metronidazole. We recommend that CPEnt detection should be included when diagnosing patients with presumed antibiotic-associated diarrhea.

Comparative analysis of prevalence, risk factors, and molecular epidemiology of antibiotic-associated diarrhea due to Clostridium difficile, Clostridium perfringens, and Staphylococcus aureus

We prospectively studied the comparative epidemiology and risk factors for Clostridium difficile, Clostridium perfringens, and Staphylococcus aureus antibiotic-associated diarrhea (AAD). Four thousand six hundred fifty-nine inpatient fecal specimens (11 months) were tested for C. difficile cytotoxin, C. perfringens enterotoxin, and S. aureus by Vero cell assay, enzyme-linked immunosorbent assay, and growth on fresh blood agar, respectively. Two distinct age-, sex-, and location-matched control patient groups were used for multivariate logistic regression risk factor analyses: symptomatic patients who were AAD pathogen negative and asymptomatic patients with histories of recent antimicrobial therapy. All AAD pathogen isolates were DNA fingerprinted. In AAD cases, the prevalences of C. difficile cytotoxin, C. perfringens enterotoxin, and S. aureus were 12.7%, 3.3%, and 0.2%, respectively (15.8% overall). Age of >70 years was a common risk factor. Other risk factors for infective AAD and C. difficile AAD included length of hospital stay and use of feeding tubes (length of stay odds ratios [OR], 1.017 and 1.012; feeding tube OR, 1.864 and 2.808). Female gender and use of antacids were significantly associated with increased risk of C. perfringens AAD (OR, 2.08 and 2.789, respectively), but unlike what was found for C. difficile AAD, specific antibiotic classes were not associated with increased risk. A limited number of genotypes caused the majority of C. difficile and C. perfringens AAD cases. Similar to what was found for C. difficile AAD, there was epidemiological evidence of C. perfringens AAD case clustering and reinfection due to different strains. C. difficile AAD was approximately 4 and 60 times more common than C. perfringens AAD and S. aureus AAD, respectively. Risk factors for these AAD pathogens differed, highlighting the need to define specific control measures. There is evidence of nosocomial transmission in cases of C. perfringens AAD.

Small Intestinal Infections

The differential diagnosis of small intestinal infections is broad, making the identification and management of these disorders challenging. The majority of cases of acute diarrhea are self-limited and do not require diagnostic evaluation or treatment. Most patients do not require specific therapy, and treatment should focus on fluid and electrolyte replacement. In patients with severe, persistent, or chronic diarrhea, a careful medical history and routine stool testing are helpful in determining the cause. Pathogen-specific therapy should be given in patients in whom a pathogen is identified. In those without an identifiable pathogen, antidiarrheal agents are helpful in reducing the number of bowel movements and preventing further dehydration. Endoscopy may be helpful in patients with severe diarrhea and a negative stool evaluation, particularly in HIV-infected patients with chronic diarrhea. Surgery has a limited role in the management of small intestinal infections, but may be lifesaving in patients with intestinal perforation or small bowel obstruction.

Foal diarrhoea between 1991 and 1994 in the United Kingdom associated with Clostridium perfringens, rotavirus, Strongyloides westeri and Cryptosporidium spp

A case control study of foal diarrhoea in the United Kingdom was carried out over a 3-year period. Clostridium perfringens was significantly associated with foal diarrhoea (Odds Ratio (OR) = 3.0), being isolated from 57% of 421 animals with diarrhoea but from only 27% of 223 healthy foals. Also, C. perfringens was significantly associated with fatal diarrhoea (OR = 4.5). About half of diarrhoea with a fatal outcome was attributable to this organism. The other pathogens significantly associated with diarrhoea were rotavirus (OR = 5.6), Cryptosporidium spp. (OR = 3.2) and the nematode Strongyloides westeri, which was significant only when present in large numbers (> 2000 eggs/g of faeces: OR = 6.1). Salmonella spp. (OR = 14.2) and Cryptosporidium spp. (OR = 3.0) were the only other pathogens associated with fatal illness. Overall, C. perfringens, rotavirus, and large numbers of Cryptosporidium spp. or S. westeri were isolated from 80% of foals with diarrhoea. Thermophilic Campylobacter spp., Yersinia enterocolitica, Escherichia coli and other parasites were not associated with diarrhoea. Carriage of C. perfringens, rotavirus and Cryptosporidium spp. was significantly greater in healthy foals in contact with cases of diarrhoea than in foals that were not in contact with diarrhoea (P < 0.05). There were no statistical interactions between any of the pathogens associated with diarrhoea although separate cases from one location often involved more than one pathogen.

An investigation into Clostridium perfringens enterotoxin-associated diarrhoea

An investigation was carried out to establish the incidence of diarrhoea associated with the presence of enterotoxigenic Clostridium perfringens. The results indicate a high risk group, namely elderly hospitalized patients, who should be investigated for this organism in a similar way to Clostridium difficile if symptoms occur. The significance of antibiotic association is suggested and cross-infection was shown to be a possibility. Detection of the enterotoxin was accompanied in all cases by the presence of high faecal counts of enterotoxigenic strains of C. perfringens.