Evaluation of the effects of storage in two different swab fabrics and under three different transport conditions on recovery of aerobic and anaerobic bacteria.

Recovery of six anaerobic and five aerobic pathogens from viscose swabs and polyurethane swabs (Culturette EZ) was evaluated quantitatively, and transport in aerobic dry tubes, aerobic Amies transport medium (Transwab), and anaerobic universal transport medium (Port-a-Cul) was compared. The Culturette EZ in aerobic dry tubes gave the highest recovery levels. Data obtained with clinical specimens confirmed these results.

The effect of FCE 22891, a new oral penem, on faecal flora anaerobes and their fermentation end products in patients with chronic obstructive pulmonary disease.

The influence of FCE 22891 on the faecal flora was investigated in 11 patients with an acute exacerbation of chronic obstructive pulmonary disease (COPD). Colony counts of faecal (an)aerobes and concentrations of their short-chain fatty acids and organic acids were determined simultaneously in fresh faeces before, during and after administration of the drug, and compared to those of healthy human volunteers. The MIC of FCE 22891 for the 142 isolated anaerobes was determined, and compared to the biologically active concentration of the drug in faeces. The Bacteroides colony counts of the patients increased significantly by day 9 compared to day 3, but were significantly lower than those of the healthy controls before, during and after the study. Significant changes in short-chain fatty acids and organic acid concentrations occurred in faeces of the patients during and after treatment, and especially when compared to healthy controls. A strong increase in MICs during treatment was found in Clostridium species, other than Clostridium difficile. FCE 22891 had only a moderate effect on the composition of the anaerobic faecal flora, but bacterial fermentation was mainly disturbed before and early on in treatment, which could have been caused by the disease.

Anaerobes and their fermentation products in faeces of patients with familial adenomatous polyposis before and after subtotal colectomy and ileorectal anastomosis.

In view of the importance of short-chain fatty acids (SCFA) for the colonic epithelial function and their possible relation with the reported spontaneous regression of rectal polyps after subtotal colectomy with ileorectal anastomosis, we compared the SCFA concentrations in faeces of five familial adenomatous polyposis (FAP) patients before, and in 10 FAP patients after operation to each other and to those of 10 healthy controls. Anaerobe cultural counts and concentrations of organic acids were also investigated in the same faecal samples from FAP patients and controls. The preoperative cultural counts were not significantly different from those of the controls. After colectomy, the Bacteroides (P < 0.002; P < 0.02), and bifidobacteria counts (P < 0.02; P < 0.005) were decreased compared to controls and untreated FAP patients. The ratio of acetic acid to total SCFA significantly increased, which coincided with a proportional decrease of the other SCFA. The frequently observed regression of rectal polyps after colectomy cannot be explained from these results. One would rather expect a possible stimulation of polyp growth and dedifferentiation of colonic epithelial cells.

The effect of ceftriaxone on the anaerobic bacterial flora and the bacterial enzymatic activity in the intestinal tract.

The normal flora of the intestinal tract, mainly consisting of anaerobic bacteria, protects the host against colonization by pathogenic microorganisms. Antimicrobial treatment with ceftriaxone may influence the colonic microflora and as a consequence, the protective effect. Ten healthy volunteers received 1 g of ceftriaxone intramuscularly for five days. This resulted in a significant decrease (p less than 0.05) of the mean cultural counts (+/- SEM) of total anaerobes from 10.67 (0.11) (prior to treatment) to 9.02 (0.45) and 8.97 (0.46) at days 3 and 5, respectively (during treatment). After treatment (days 10 and 15-19), the cultural counts of anaerobes returned to 10.17 (0.16) and 10.44 (0.18), respectively. Bacterial enzymes may serve as an indicator of protective microflora. beta- aspartylpeptidase and deoxycholate hydrolase activity was determined in faecal supernatants of the volunteers and compared with anaerobic culturing. Both enzymatic activities show a significant correlation with the total number of anaerobes present at day 3 of deftriaxone treatment. At day 5 and 8 only beta-aspartylpeptidase showed significant correlations with cultural counts of total anaerobes, Bacteroides spp. or bifidobacteria. At day 15 to 19 (ten to 14 days after treatment) beta-aspartylpeptidase showed only a significant correlation with the number of Bacteroides spp. This indicates that changes in the indigenous bacterial flora during and shortly after treatment with ceftriaxone can be monitored by determination of beta-aspartylpeptidase. Recovery of the intestinal flora is difficult to assess in this manner.

Short-chain fatty acid and organic acid concentrations in feces of healthy human volunteers and their correlations with anaerobe cultural counts during systemic ceftriaxone administration.

Short-chain fatty acid (SCFA) and organic acid concentrations and (an)aerobe cultural counts were determined simultaneously in fresh feces from 10 human volunteers before, during, and after 5 days of single-dose ceftriaxone administration. The changes and the correlation coefficients between these variables were tested to be significant (P less than 0.05). to investigate whether significant changes in the intestinal microflora could be predicted by significant changes in SCFA/organic acid concentrations. Multivariate analysis was used with the same objective. Significant decreases in most SCFA, total SCFA (0.01 less than P less than 0.02), and pyruvic acid (0.02 less than P less than 0.05) concentrations in feces were found on day 3 of treatment and also on day 5, with the exception of the pyruvic acid concentrations. Lactic acid concentrations, however, were significantly increased (0.01 less than P less than 0.02) on day 5. All anaerobic cultural counts were significantly decreased (P less than 0.05) on days 3 and 5 of treatment except those for Clostridium difficile agar, which were only decreased on day 5. Highly significant correlations were found on day 3 between the total anaerobe counts (P less than 0.001), the Bacteroides counts (P less than 0.001), and propionic acid, of which the latter had a predictive value during treatment. The results of multivariate analysis were significant but did not have a predictive value. From this study we can conclude that propionic acid concentrations during ceftriaxone treatment in healthy volunteers have a predictive value for the Bacteroides cultural counts. The results of this study must be confirmed by those from patients treated with ceftriaxone.

Low-dose ciprofloxacin for selective decontamination of the digestive tract in human volunteers.

The effect on the faecal aerobic and anaerobic flora of ciprofloxacin given in low doses for selective decontamination of the digestive tract was investigated in ten human volunteers. The volunteers received 50, 100 and 200 mg of ciprofloxacin every 12 h for five days at intervals of three and five weeks respectively. No significant differences in the numbers of aerobes or anaerobes were seen after the 2 x 50 mg regime. The colony counts of most anaerobes and the total aerobe count were significantly decreased after the 2 x 100 mg [corrected] regime. Whereas the aerobe count was also significantly decreased after administration of 2 x 200 mg, the anaerobe count remained stable. Clostridium difficile was not detected during or after treatment. From these results it can be concluded that ciprofloxacin in a dose of 2 x 200 mg [corrected] can be recommended for selective decontamination of the digestive tract.

Short-chain fatty acid and organic acid concentrations in feces of 10 human volunteers and their correlation with anaerobe cultural over a 15-month period.

Short-chain fatty acid (SCFA) and organic acid concentrations were determined with gas-liquid chromatography (GLC) in fresh feces from 10 healthy volunteers, simultaneously with their fecal cultural counts. To find a simple and reliable method to detect disturbances in fecal flora, we calculated the intraindividual correlations between the concentrations determined by GLC and the fecal cultural counts. Twenty-three (4.7%) significant (P less than 0.05) linear correlations were thus found in nine of the volunteers. Using multivariate analysis, we attempted to assign fecal samples to individuals in accordance with their SCFA, cultural count, and organic acid profiles. Percentages of samples thus classified correctly were 49, 39, and 29, respectively. We conclude from this study that these percentages represent the normal situation in a group of healthy humans and that the low percentage of significant correlation coefficients shows that the relation between fecal SCFA/organic acid concentrations and fecal cultural counts has not been established.

The effect of new broad-spectrum antibiotics on faecal flora of cancer patients.

The effects of newly available broad-spectrum antibiotics, used for infection prophylaxis and therapy in cancer patients, on faecal aerobic and anaerobic bacteria were investigated. Quantitative and qualitative aerobic and anaerobic cultures were performed in 34 patients before therapy and between the sixth and eleventh day of therapy. Of the two prophylactic regimens norfloxacin plus amphotericin-B eliminated Enterobacteriaceae and enterococci without encouraging growth of yeasts or Clostridium difficile whereas trimethoprim-sulphamethoxazole did not eliminate enterococci and colonization with toxin producing C. difficile occurred in two of ten patients. The effect of the two infection prophylaxis regimens on counts of faecal anaerobes was comparable. Monotherapy with ceftazidime and combination therapy with ceftazidime plus tobramycin did not result in major changes (greater than or equal to 3 log increase or decrease) in faecal anaerobic bacteria. Enterobacteriaceae were eliminated except in one patient treated with ceftazidime. The effect of these therapeutic regimens on enterococci was variable. Colonization by yeasts or by toxin negative C. difficile (two of three patients) were found in the ceftazidime group only. During combination therapy with piperacillin plus amikacin for fever during granulocytopenia signs of a disturbed faecal flora were found in one of three patients. Changes in faecal anaerobic bacteria were most marked in the ceftazidime plus piperacillin group. Moreover the isolation of a toxin positive C. difficile occurred in this group, in a patient who was colonized with toxin negative C. difficile before treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Short-chain fatty acids and succinate in feces of healthy human volunteers and their correlation with anaerobe cultural counts.

Short-chain fatty acids (SCFA) and succinate in fresh feces from 10 healthy human volunteers were detected with gas-liquid chromatography and were correlated with their fecal cultural counts. The SCFA content of feces did not change significantly after freezing, but the cultural counts of total anaerobes and bifidobacteria showed significant changes (0.001 less than P less than 0.01). A significant negative correlation (r = -0.78; 0.01 less than P less than 0.02) was found between the bifidobacteria cultural counts and the succinic acid concentration in fresh feces, which disappeared after freezing of the samples. Because of the significant differences in cultural counts and the shift in significant correlations after freezing, it is important to use fresh fecal samples for these correlation studies. Lactic acid and i-caproic acid were not found in the fecal samples. The results show that SCFA and organic acid concentrations cannot replace (an)aerobe cultural counts in fecal flora studies of healthy human volunteers because of the low rate of significant correlations between these two.

Variations in the anaerobic faecal flora of ten healthy human volunteers with special reference to the Bacteroides fragilis-group and Clostridium difficile.

Ninety nine stool specimens of ten healthy human volunteers were collected over a one year period, and processed anaerobically. The individual variations in intestinal colonization with bacteria of the Bacteroides fragilis-group were detected, using the Bacteroides Bile Esculin medium and an identification scheme for bile-resistant Bacteroides species. Clostridium difficile agar supplemented with cycloserine/cefoxtin was used to detect the incidence of C. difficile in this group. The species of the B. fragilis-group most often detected were: B. vulgatus (in 31 samples from ten persons), B. uniformis (22/9), B. fragilis (19/7). C. difficile was never detected in this group. The mean total anaerobic cultural counts (log) of the ten volunteers varied between 9.94 and 10.91. This shows that interindividual variations in anaerobic cultural counts of about one log are common. In spite of these moderate interindividual variations, intraindividual variations in time of up to three log were detected. The mean Bacteroides cultural counts showed a variation between 8.83 and 10.24. The mean DMCCs of the ten volunteers were between 10.22 and 10.73. We conclude that at least a three to four log difference from the control samples will be required to establish a significant change in anaerobic cultural count due to antibiotic treatment.

The presence of antibody-coated anaerobic bacteria in asymptomatic bacteriuria during pregnancy.

Quantitative anaerobic culture of urine samples obtained from 593 pregnant women by suprapubic bladder aspiration was performed to establish the involvement of anaerobic bacteria in asymptomatic urinary tract infections. The fluorescent antibody (FA) test was applied to the sediments of bladder aspirates to determine the site of infection. Anaerobic bacteriuria (greater than or equal to 10(4) microorganisms/ml of urine) was found in 34 patients, of whom five were FA-positive. These anaerobes were identified as Lactobacillus minutus, Veillonella parvula (two patients). Clostridium putrefaciens, and Peptostreptococcus anaerobius. Aerobic bacteriuria (greater than 10(4) microorganisms/ml of urine) was detected in 27 patients, of whom 13 were FA-positive. In 10 women with mixed aerobic/anaerobic bacteriuria, no FA-positive bacteria were found. The finding of FA-positive anaerobes may indicate that these organisms are involved in silent renal infection.

The prevalence of anaerobic bacteria in suprapubic bladder aspirates obtained from pregnant women.

The incidence of asymptomatic bacteriuria due to aerobic, facultative anaerobic and strictly anaerobic bacteria during pregnancy was determined in 185 patients admitted for complications of pregnancy, using suprapubic bladder aspiration. Anaerobic bacterial counts of 103 per ml urine or higher were detected in 6.4 per cent of the specimens. The incidence of anaerobic bacteriuria seems comparable to that of bacteriuria due to aerobic and facultative anaerobic micro organisms. In our group of patients the incidence of the latter was 5.4%. The presence of anaerobic bacteria was not confined to the occurrence of a particular species. Peptostreptococcus species, Veillonella species, Bacteroides species, Eubacterium species, Clostridium species and Bifidobacterium species were isolated from specimens in concentrations of more than 103 per ml. Consequences of asymptomatic bacteriuria during pregnancy are totally uncertain. Further investigation is necessary to obtain insight into the effect of bacteriuria due to anaerobes upon the outcome of pregnancy.