Distribution of MIC Values of Various Antibiotics against Extended-spectrum Beta-lactamase (ESBL)-producing Klebsiella pneumoniae / 감염

BACKGROUND: Extended-spectrum beta-lactamases (ESBLs) confer resistance to extended-spectrum cephalosporin (e.g., cefotaxime, ceftazidime) and aztreonam. But the diversity of ESBLs results in various susceptibility profiles with different beta-lactams. To study the relative in vitro activities of various beta-lactams and non-beta-lactam antibiotics against the clinical isolates of ESBL-producing K. pneumoniae, we determined the MIC (minimum inhibitory concentration) of various antimicrobials. METHODS: Fifty-seven isolates of K. pneumoniae which produced ESBL and 63 isolates which did not produce ESBL from 3 university hospitals in Korea were tested. The MIC values of antimicrobials were determined by agar dilution method and detection of ESBL production was performed by double disk synergy test. RESULTS: The MIC values of beta-lactams against K. pneumoniae which produced ESBLs exhibited heterogeneous susceptability profiles. In differentiation of ESBL production, MIC value of 8 ug/mL (breakpoint of intermediate resistance) of ceftazidime was more sensitive and more specific than that of cefotaxime or aztreonam. MIC50 values of gentamicin, amikacin and ciprofloxacin against K. pneumoniae that produced ESBL were significantly higher than those against Non-ESBL producing isolates (P<0.001), suggesting that ESBL producing isolates are multi-drug resistant. CONCLUSION: The level of resistance to various beta-lactams of K. pneumoniae which produced ESBL was heterogeneous. ESBL-producing K. pneumoniae showed higher resistance to aminoglycoside and quinolone antibiotics. Ceftazidime was the most appropriate antibiotic to differentiate ESBL production.

Three Cases of Vibrio cholerae Serogroup Non-O1 Septicemia / 감염

Non-O1 V. cholerae usually causes endemic disease. Common clinical manifestations of this infection involve gastroenteritis, sepsis, and wound infection. In Korea, six cases of infection with this pathogen have been reported. From 1995 to 1996, non-O1 V. cholerae was isolated from blood of three patients of sepsis in this hospital. Two of them had liver cirrhosis as an underlying disease. One patient died of progressive sepsis and another two patients recovered. The isolates were identified by API 20E(API system, BioMerieux, France) and their biochemical properties were characterized. The serotypes of two isolates were determined to be O2 and O24. These cases, with the previous reports, suggest that non-O1 V. cholera should be considered as a pathogen causing septicemia in patients who have underlying disease of liver cirrhosis during summer.

Biliary Tract & Pancreas; Effectiveness of Endoscopic Ultrasonography in Detecting the Extrahepatic Choledocholithiasis / 대한소화기내시경학회지

BACKGROUND/AIMS: Ultrasonography is the easiest, fastest procedure for the diagnosis of choledocholithiasis, but the diagnostic failure are mostly because of the intrapancreatic level of this condition and the absence of bile duct dillatation. Endoscopic ultrasonography is a promising procedure for the diagnosis of extrahepatic cholestasis due to noninvasiveness and accuracy in the digestive gas interposition. The aim of this study was to prospectively compare the diagnostic accuracy of endoscopie ultrasonography with abdominal ultrasonography and endoscopic retrograde cholangiography in 66 patients with suspected choledocholithiasis. METHODS: All of the patients had abdominal ultrasonography, endoscopic ultrasonography ~and endoscopie retrograde cholangiography within 72 hours and final diagnosis was determined by endoseopic retrograde cholangiography with sphincterotomy. RESULTS: (l) Choledocholithiasis was confirmed in 45 patients: Thirteen patients had nondilated common bile ducts and 20 patients had stones with diamerer < 1 cm. (2) Endoscopic ultrasonography was more sensitive(95.5%) than abdominal ultrasonography (44.4%: P<0.0001) and similar to endoscopic retrograde cholangiography (97.8%). Specificity was same as 100% in 3 diagnostic tools. (3) Endoscopic ultrasonography was superior to abdommal ultrasonography for the diagnosis of choledocholithiasis with nondilated common bile duct(100% vs 15.3%, P<0.0001) and with less than 1cm sized small stone(100% vs 10.0%, P<0.0001). Endoscopic ultrasonography results did not depend on stone diameter or common bile duct dilatation. CONCLUSIONS: Endoscopic ultrasonography could be an accurate and safe diagnostic tool for the diagnosis of choledocholithiasis and could be promising especially in the cases with difficult cannulation of bile duct and gal1 stone pancreatitis.