Diagnostic value of five commercial tests for the rapid diagnosis of Clostridium difficile-associated disease.

We compared five commercial immunoassays (Biostar OIA CdTOX AB, ImmunoCard Toxins A&B - Meridian, Xpect C. difficile toxin A/B -Remel, C. difficile toxin A test- Oxoid, and TOX A/B QUIK CHEK- Techlab) which allow a rapid diagnosis of C. difficile associated disease. The tests were performed directly on patient's stool specimen submitted for routine investigation of C. difficile infection from two University Hospitals in Brussels. The cell cytotoxicity assay was considered as the gold standard. Of the 100 stool specimens included in the study 23 were positive for C. difficile toxin. The sensitivity, specificity, positive and negative predictive values were respectively, 95.7%, 100%, 100% and 98.7% for TOX A/B QUIK CHEKTM, 91.3%, 100%, 100% and 97.5% for ImmunoCard Toxins A&B and for Xpect C. difficile toxin A/B, 87%, 100%, 100% and 96.3% for OIA CdTOX AB and 87%, 98.7%, 97.2% and 96.3% for C. difficile toxin A test. The differences were not statistically significant (p > 0.05). These data suggest that the tested immunoassays are acceptable for rapid detection of C. difficile toxin.

Antimicrobial susceptibility of clinical isolates of non-jejuni/coli campylobacters and arcobacters from Belgium.

OBJECTIVES: To determine the susceptibility of non-jejuni/coli campylobacters and arcobacters isolated from diarrhoeal stool specimens in Belgium. METHODS: The MICs were determined using Etest for six antimicrobial agents including ampicillin, erythromycin, nalidixic acid, ciprofloxacin, gentamicin and tetracycline for the most frequently isolated non-jejuni/coli campylobacter and arcobacter strains in two University Hospital laboratories between 1995 and 2005. RESULTS: In total, 85 Campylobacter upsaliensis, 20 Campylobacter concisus, 11 Campylobacter fetus, 61 Arcobacter butzleri and 10 Arcobacter cryaerophilus isolates were tested. Most C. upsaliensis strains were susceptible to ampicillin (100%), gentamicin (100%), ciprofloxacin (94.1%) and tetracycline (100%), whereas 11.8 and 12.9% were resistant to nalidixic acid and erythromycin, respectively. For A. butzleri, 78.7% of isolates were susceptible to ampicillin and erythromycin. Most A. butzleri isolates were susceptible to ciprofloxacin (96.7%), nalidixic acid (82.0%), gentamicin (100%) and tetracycline (100%). All C. concisus strains were fully susceptible to ampicillin and tetracycline, but 5% of them were resistant to gentamicin, ciprofloxacin and erythromycin. Nearly all C. fetus and A. cryaerophilus strains were susceptible to erythromycin but the results should be interpreted with caution since only a small number of strains were tested. CONCLUSIONS: Fluoroquinolones should be considered in the treatment of severe C. upsaliensis and A. butzleri infection. When clinically indicated, erythromycin remains the first choice for the treatment of intestinal campylobacteriosis caused by C. concisus and C. fetus.

Arcobacter species in humans.

During an 8-year study period, Arcobacter butzleri was the fourth most common Campylobacter-like organism isolated from 67,599 stool specimens. Our observations suggest that A. butzleri displays microbiologic and clinical features similar to those of Campylobacter jejuni; however, A. butzleri is more frequently associated with a persistent, watery diarrhea.