BACKGROUND: The aim of this study was to compare the BD Phoenix (Beckton Dickinson Diagnostic Systems, USA) extended-spectrum beta-lactamase (ESBL) test with the Clinical and Laboratory Standards Institute (CLSI) ESBL phenotypic confirmatory test by disk diffusion (CLSI ESBL test) in Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Proteus mirabilis. METHODS: We tested 224 clinical isolates of E. coli, K. pneumoniae, K. oxytoca and P. mirabilis during May 2006 to March 2007. These isolates were examined by the Phoenix and the CLSI ESBL tests simultaneously. For the isolates showing discordant results between the two tests, boronic acid disk test was performed to differentiate AmpC beta-lactamase and ESBL. RESULTS: Among the 224 clinical isolates, 75 and 79 isolates were positive for ESBL by CLSI ESBL test and Phoenix test, respectively. Having detected 4 more isolates as ESBL-producers, Phoenix test showed a 98.2% agreement with a 100% sensitivity and 97.3% specificity compared with CLSI ESBL test. Among the four false positive isolates, three were AmpC-positive but ESBL-negative. CONCLUSIONS: The BD Phoenix ESBL test was sensitive and specific, and can be used as a rapid and reliable method to detect ESBL production in E. coli, Klebsiella species, and P. mirabilis.
Automation ; Bacterial Proteins/classification/*metabolism ; Disk Diffusion Antimicrobial Tests ; Escherichia coli/drug effects/*enzymology/isolation & purification ; Humans ; Klebsiella/*enzymology ; Klebsiella oxytoca/drug effects/enzymology/isolation & purification ; Klebsiella pneumoniae/drug effects/enzymology/isolation & purification ; *Microbial Sensitivity Tests ; Proteus mirabilis/drug effects/*enzymology/isolation & purification ; Reagent Kits, Diagnostic ; Sensitivity and Specificity ; beta-Lactamases/classification/*metabolism

Acute phlegmonous gastritis is an uncommon disease, often fatal condition characterized by suppurative bacterial infection of the gastric wall. It has a high mortality rate mainly because the diagnosis is usually made late. Until recently, gastrectomy in combination with antibiotics was recommended. We had experienced a case of 66-year-old man presented with epigastric pain, nausea, vomiting, and hematemesis, followed by aspiration pneumonia. At upper gastrointestinal endoscopy, the gastric lumen was narrow, and the mucosa was severely inflamed, which was erythematous, swelled, and showed necrotic areas covered with purulent exudate. Klebsiella oxytoca and Acinetobacter lwoffii were isolated in the gastric tissue culture. Contrast-enhanced computerized tomography scan of abdomen demonstrated diffuse gastric wall thickening and an intramural abscess in the gastric antral wall. Although delayed gastric emptying by gastroparesis prolonged the in-hospital period, the only medical treatment with antibiotics alone successfully cured the patient without gastrectomy.
Acinetobacter/isolation & purification ; Acute Disease ; Aged ; Anti-Bacterial Agents/*therapeutic use ; Anti-Infective Agents/therapeutic use ; Cefotaxime/therapeutic use ; Ceftriaxone/therapeutic use ; Ciprofloxacin/therapeutic use ; Drug Resistance, Multiple, Bacterial ; Drug Therapy, Combination ; Gastritis/*diagnosis/drug therapy/microbiology ; Gastroparesis/*diagnosis/microbiology ; Gastroscopy ; Humans ; Imipenem/therapeutic use ; Klebsiella oxytoca/isolation & purification ; Male ; Ofloxacin/therapeutic use ; Pneumonia/diagnosis/drug therapy ; Tomography, X-Ray Computed