[Epidemiology of extended spectrum beta-lactamases (ESBL) Enterobacteriaceae in a General Hospital, South of France, 1999-2007]

PURPOSE OF THE STUDY

The global epidemiology of extended spectrum betalactamases (ESBL) producing Enterobacteriaceae has evolved in recent years with the emergence of a new type of ESBL: CTX-M, mainly in Escherichia coli. These CTX-M type producing Enterobacteriaceae are responsible for both nosocomial and, more recently, community infections, including urinary tract infections. The aim of our work is to study ESBL producing Enterobacteriaceae evolution between 1999 and 2007 in the population from the Centre Hospitalier du Pays-d'Aix (CHPA), a general hospital from South of France.

PATIENTS AND METHODS

ESBL producing strains of Enterobacteriaceae isolated in odd years between 1999 and 2007 from clinical isolates of all origins have been phenotypically identified and their ESBL genotyped. Molecular and epidemiological data from our hospital health-care associated infection committee were analyzed.

RESULTS

Two hundred and sixty-two ESBL producing isolates were studied. Within ESBL producing Enterobacteriaceae, Enterobacter aerogenes was predominant in 1999 (48.7% of isolates), and decreased to 18.8% of isolates in 2007. On the other hand, E. coli, which represented 10.5% of ESBL isolates in 1999, grew up to 37.5% of the isolates in 2007. ESBL prevalence in E. coli increased during this period from 0.3 to 2.5%. Simultaneously, ESBL, predominantly TEM-24 in 1999, were replaced by CTX-M in 2007, among which CTX-M-15 is predominant (88% of CTX-M).

CONCLUSION

Our study confirms a major change in ESBL epidemiology in CHPA, with the emergence of CTX-M type ESBL, mainly CTX-M 15, and an increase of ESBL prevalence in E. coli.

Intrarectal injection of glycerol induces hypersensitivity to rectal distension in healthy subjects without modifying rectal compliance

BACKGROUND

Rectal sensory thresholds are lowered in patients with irritable bowel syndrome (IBS), reflecting visceral hyperlagesia, which might be related to subclinical inflammation.

AIM

To evaluate the effects of an intraluminal injection of glycerol, a mucosal irritant, on rectal tone and perception of distension in 12 healthy subjects.

METHODS

Rectal tone was evaluated with a barostat. First sensation, need to defecate and pain thresholds were evaluated during isobaric phasic distensions, before and 20 and 120 min after injection of 10 ml glycerol in the rectum.

RESULTS

Baseline bag volume (97.9 +/- 56.2 ml) significantly decreased 20 min (49.7 +/- 42.2 ml; P= 0.026) and 120 min (66.5 +/- 38.3 ml; P= 0.050) after injection of glycerol, indicating its hypertonic effect. The pressure defining sensory thresholds was decreased significantly 20 min after glycerol injection: first sensation, 14.6 +/- 2.9 versus 18.3 +/- 7.2 mm Hg (P = 0.01); need to defecate, 19.6 +/- 3.7 versus 26.0 +/- 6.9 mm Hg; pain, 23.8 +/- 4.5 versus 35.6 +/- 9.5 mm Hg (P = 0.001). This effect was maintained for 120 min after injection of glycerol. Slopes of the compliance curves did not differ before and after injection of glycerol.

CONCLUSIONS

Intraluminal injection of glycerol significantly increases rectal tone and sensitizes healthy volunteers to rectal distension, since they show significantly lower thresholds after glycerol. This could constitute a model of visceral hypersensitivity in healthy volunteers.

Detection and incidence of drug-induced liver injuries in hospital: a prospective analysis from laboratory signals

AIMS

Liver damage remains the most frequent type of adverse drug reaction (ADRs) that can lead to the withdrawal of a drug from the market. The abnormal laboratory data identified by computerized hospital information systems can be used in order to improve the detection of ADRs. Our objectives were to assess the detection and incidence of drug-induced liver abnormalities in a university hospital inpatient population and to evaluate the underreporting rate of drug-induced liver injury.

METHODS

We conducted a prospective study performed 1 week per month from June to October 1997. We selected patients by a computerized process using biochemistry laboratory data, based on serum enzyme values, alanine aminotransferase (over 2 fold normal) and alkaline phosphatase (over 1.5 fold normal).

RESULTS

Among 1976 ALT and 1814 AP assays performed during the period of the study, 156 (7.9%) and 159 (8.8%) tests, respectively, fell into the selected criteria. These concerned 147 patients. Among these patients, 13 (8.8%) cases of drug-induced liver injuries were suspected. Seven cases were asymptomatic. Six cases were classified as serious by these criteria: hospitalization to investigate the cause of health status impairment (4 patients), prolongation of hospitalization (1 patient) and life-threathening (1 patient). Using the hospitalization database, the incidence of drug-induced liver injuries was estimated as 6.6 per 1000 inpatients a week. Only 1 case was reported by physicians in the same period.

CONCLUSIONS

Computerization of biochemical data would allow the development of systems to improve detection of drug-induced injury. Moreover, underreporting remains important for such potentially serious ADRs, even in a university hospital.

Influence of age on rectal tone and sensitivity to distension in healthy subjects

Hypersensitivity to rectal distension is frequently observed in patients with irritable bowel syndrome (IBS). However, few data are available about the influence of age on rectal sensory thresholds and tone. The aim of this study was to measure rectal sensory thresholds and tone with a barostat in 12 healthy subjects (aged 86 +/- 4 years, eight females, four males) as compared with 12 young healthy male controls (26 +/- 1 years). Isobaric phasic distensions were performed in the fasted state (increment of 4 mmHg, steps of 5 min, interval of 5 min). Rectal tone changes were then measured as changes in volume of the barostat bag, the pressure being kept constant. After a baseline recording of 1 h, a 1000-kcal meal was served and the tone recorded until return to baseline. Rectal sensory thresholds were significantly higher in aged subjects. First sensation, sensation of urge to defaecate and sensation of pain were triggered at 21.1 +/- 3.2 mmHg, 30.4 +/- 5.4 mmHg and 40.5 +/- 5.0 mmHg, respectively, in aged subjects, vs 13.3 +/- 4.6 mmHg (P < 0.05), 20.7 +/- 1.0 mmHg (P < 0.001) 31.3 +/- 1.7 mmHg (P < 0.001) in controls. Rectal compliance was not significantly different between the two groups. Mean barostat bag volume was 104 +/- 13 mL in fasting aged subjects and 125 +/- 23 mL in controls (NS). After the meal, the barostat bag volume decreased by 69 +/- 11% during 85 +/- 17 min in aged subjects and 75 +/- 14% during 89 +/- 15 min in young controls (NS). Rectal sensory thresholds triggered by distension are increased in aged healthy subjects while compliance and tone are not different. Age should be considered as a confounding factor when studying rectal sensitivity and further studies in aged patients with IBS should include a group of control subjects within the same range of age as studied patients.

The kappa agonist fedotozine relieves hypersensitivity to colonic distention in patients with irritable bowel syndrome

BACKGROUND & AIMS

Visceral hypersensitivity plays a major role in the pathophysiology of inflammatory bowel syndrome (IBS). Opioid kappa receptors on afferent nerves may modulate it and may be the target of new IBS treatments. The aim of this study was to evaluate the effects of fedotozine, a potent and selective kappa agonist, on responses to colonic distention and colonic compliance in patients with IBS.

METHODS

Fourteen patients with IBS (Rome criteria; 50 +/- 12 years; 6 men and 8 women) were included in a randomized double-blind, crossover trial comparing the effect of an intravenous infusion of 100 mg fedotozine or saline on sensory thresholds elicited by left colon phasic distention (4-mm Hg steps for 5 minutes) up to a sensation of abdominal pain. Colonic compliance was compared by the slope of the pressure-volume curves built on placebo and on fedotozine.

RESULTS

In the fedotozine group, thresholds of first perception (28.7 +/- 5.9 mm Hg) and pain (34.7 +/- 5.5 mm Hg) were significantly greater than with placebo (23.3 +/- 4.5 and 29.0 +/- 3.5 mm Hg, respectively; P = 0.0078). Colonic compliance was 9. 20 +/- 3.87 mL. mm Hg-1 with placebo and 8.73 +/- 3.18 mL. mm Hg-1 with fedotozine (not significant).

CONCLUSIONS

Fedotozine increases thresholds of perception of colonic distention in patients with IBS without modifying colonic compliance. Fedotozine seems capable of reversing visceral hypersensitivity observed in these patients and could have some beneficial action on their symptoms.

[Determination of the isoelectric point of beta-lactamases isolated from 67 Klebsiella oxytoca strains and phenotype behaviour against eight beta-lactam antibiotics]

Klebsiella oxytoca is naturally resistant to aminopenicillins and carboxypenicillins by production of a chromosomal beta-lactamase but susceptible to third generation cephalosporins. The third generation cephalosporins activity may be reduced by: overproduction of the chromosomally encoded beta-lactamase or an extended-spectrum beta-lactamase. These activity modification are rarely found in the hospital of Aix-en-Provence (France). The activity modification rate of K. oxytoca resistant by one of these mechanisms between 1986 and 1991 are 3.6% for chromosomally encoded beta-lactamase overproduction and 0.7% for acquisition of an extended-spectrum beta-lactamase. We have determined the isoelectric point (pI) by isoelectrofocusing of the beta-lactamases isolated from 67 K. oxytoca and the activity of 8 beta-lactams has been studied by disk-diffusion. 51 wild strains, 14 overproducing strains (including 2 in vitro mutants) and 2 strains with extended-spectrum beta-lactamase were studied. For every wild strain, we observed only one band except for two strains with two bands (pl 5.4 + 6.3 and pl 5.6 + 7.7). The isoelectric points for the other strains are comprised between pl 5.25 and pl 8.2: 22 pl 7.7; 13 pl 5.25; 4 pl 5.6; 4 pl 6.3; 2 pl 6.6; 2 pl 8.1 and 2 pl 8.2. In the strains with chromosomally encoded beta-lactamase overproduction we observed several bands in each extract and only the major band was considered. The isoelectric point of in vitro mutant strains with beta-lactamase overproduction was the same that the wild strains. We observed 3 pl: 5.25 - 1 pl: 5.6 - 3 pl 6.3 and 5 pl 7.7.(ABSTRACT TRUNCATED AT 250 WORDS)

[In vitro effect of cefixime against 200 strains of Branhamella catarrhalis. Comparison with cefotaxime]

The in vitro activity of cefixime was tested against 200 strains of Branhamella catarrhalis. Of these strains, 146 had been collected during 1987 from 15 different "Centres hospitaliers généraux", through a multicenter collaborative investigation organized by the "Collège de Bactériologie-Virologie-Hygiène des hôpitaux généraux". The remaining 54 strains were isolated at the "Centre hospitalier", of Aix-en-Provence. The strains originated from: bronchopulmonary collections: 80.2 per cent, sinusitis: 5.6 per cent, conjunctivitis: 4.6 per cent, otitis: 3.5 per cent, blood cultures: 0.5 per cent, miscellaneous: 5.6 per cent. Seventy-three per cent of the strains produced beta-lactamases. MIC determination was performed according to the agar dilution procedure on non-enriched Mueller-Hinton agar (30 hours incubation at 37 degrees C without CO2). The inoculum was 10(5) CFU per spot. Non beta-lactamase producing strains displayed the following MIC 50 and MIC 90 values (mg/l): amoxicillin: 0.03 - 0.125; cefotaxime: 0.06 - 1; cefixime: 0.06 - 0.5. Beta-lactamase producing strains were generally more resistant: amoxicillin: 32 - 128; cefotaxime: 1 - 2, and cefixime: 0.5 - 1.

[In vitro comparative activity of five macrolides against 190 Branhamella catarrhalis strains]

We compared the in vitro activity of 5 macrolides against 190 strains of Branhamella catarrhalis; 48 strains were isolated at Centre Hospitalier, Aix-en-Provence, the 142 others were isolated during 1987, in 15 different Centres-Hospitaliers-Généraux in France. 153 strains were betalactamase producing strains; no difference in susceptibility to erythromycin was observed on betalactamase producing and non producing strains. Three active macrolides against 100% of strains were: erythromycin (MIC 50 = 0.25 mg/l - MIC 90 = 0.50 mg/l), roxithromycin (MIC 50 = 0.50 mg/l - MIC 90 = 0.50 mg/l) and josamycin (MIC 50 = 0.50 mg/l - MIC 90 = 1 mg/l); A lower activity was noted on midecamycin (mic 50 = 2 mg/l - MIC 90 = 2 mg/l) and spiramycin (MIC 50 = 4 mg/l - MIC 90 = 8 mg/l).

[Pathogenic role of Actinomyces apart from actinomycosis. Apropos of 2 cases of acute suppurations with Actinomyces odontolyticus]

The authors report two cases of acute suppurative lesions due to Actinomyces odontolyticus. They point out the fairly high incidence of this pathogen in such conditions, either isolated or more often as part of a mixed flora. Conversely, Actinomyces odontolyticus is only exceptionally recovered in true actinomycosis.