ABSTRACT
Aim: This study evaluated the frequency of C. difficile and CDAD in the ICU of Shahid Bahonhar Hospital, Kerman, Iran
Background: Clostridium difficile [C. difficile] is the most important antibiotic associated diarrhea agent in intensive care unit [ICU] patients. Based on its toxin producing ability, C .difficile is divided to toxigenic and non-toxigenic strains
Methods: A total of 233 diarrheal samples were collected from ICU patients. The samples were cultured on Clostridium difficile medium with 5% defibrinated sheep blood containing cycloserine [500 mg/L], cefoxitin [16 mg/L] and lysozyme [5mg/L]. The isolates were confirmed as C. difficile by polymerase chain reaction [PCR] of 16s rRNA gene and the presence of toxins genes [tcdA, tcdB, cdtA and cdtB] was also confirmed. Then, the toxin production of isolates was evaluated using ELISA
Results: C. difficile was isolated from 49 [21%] out of 233 samples. The total isolates fell into the A-/B-/CDT- [48.97%], A+/B- /CDT- [28%], A+/B+/CDT- [20.4%] and A+/B+/CDT+ [2%] types. Both types of C.difficile, A-/B-/CDT- and A+/B-/CDT-, which account for 77.5% of all isolates, were unable to produce the toxin [nontoxigenic]. On the other hand, A+/B+/CDT+ and A+/B+/CDT- [22.5%], were able to produce toxin or were toxigenic
Conclusion: The frequency of C. difficile was about 21% and only 22.4% of C. difficile isolates were able to produce toxins. It is expected that C. difficile A+/B+/CDT+- are toxigenic and related to C. difficile associated diarrhea [CDAD]. Additionally, about 4.7% of hospitalized patients in ICU suffered from CDAD, which is higher than the rates reported from industrialized countries. Notably, 28% of isolates were C. difficile A+/B-/CDT- which only carries tcdA genes without toxin production
ABSTRACT
Meningococcal diseases have been recognized as an important problem in military population. Most patients with meningococcal diseases have not had a direct contact with other similar patients. Thus, asymptomatic carrier is presumably the major source of transmission of pathogenic strains. To determine the carrier rate of the newly-arrived recruits to a military center and to find out the sensitivity pattern of the isolated strains. One thousand four hundred and fifty-six tonsilopharyngeal samples were collected during a 15-month period from 2002 through 2003. All the samples were plated on chocolate agar supplemented with 3 mg/L vancomycin and 2 mg/L amphotericin B. Meningococci were identified by a standard method. Sero-grouping of part of isolated strains was carried out by the slide agglutination test. The antibiotic resistance was measured by the broth macrodilution method with penicillin, rifampicin, and ciprofloxacin. Sensitivity of part of isolated strains against two antiseptic solutions, chlorhexidine and eucalyptus inhaler, were also tested. The mean of meningococcal carrier rate in 4+1 seasons was 11.4% for the newly arrived recruits. After 1[1/2]- 2 months, it raised to 33%. Increases observed in cold seasons were considerable. During the second sampling stage, the mean carrier rate was 38% for smokers and 28% for nonsmokers. Strains isolated from carriers were phenotypically heterogeneous, with a dominance of group B [tilde27%]. All the invasive strains recovered concurrently from the patients with meningococcal diseases also belonged to this sero-group. The median of minimum inhibitory concentrations [MICs] for penicillin and rifampicin were 0.06 and 0.03 microg/mL, respectively. The MIC[50] of ciprofloxacin was 0.004. Thirteen percent of the isolates were partially resistant to penicillin. It was 8% for rifampicin. More than 60% of the isolated strains were sensitive to 1/600 dilution of chlorhexidine. It was negligible against the eucalyptus inhaler. Our results indicate that the transmission rate is strongly associated with the season. Furthermore, there is a correlation between the carrier state and smoking habit. Domination of B sero-group among the carriers and patients could be due to the lack of B antigen in the available vaccines. The resistance pattern of tested strains was similar to that of other studies