An Enterococcus gallinarum Strain Carrying Both vanA and vanC1 Genes / 대한임상병리학회지

Enterococcus gallinarum carrying both vanA and vanC1 genes were detected from a surveillance culture from a patient staying at the surgical intensive care unit for a few years. E. gallinarum, SI04, was highly resistant to vancomycin (MIC of >or=256ng/mL) and teicoplanin (MIC of >or=256ng/mL). Multiplex PCR for vanA, vanB, vanC1 and vanC2/3 genes revealed SI04 to be positive for both vanA and vanC1 genes. This finding supports the fact that genotyping is needed to classify vancomycin-resistant enterococci (VRE). This is the first report on VanC VRE accompanying vanA gene in Korea.

Nontuberculous Mycobacterial Pulmonary Infection in Immunocompetent Patients / 결핵

BACKGROUND: Nontuberculous mycobacteria (NTM) have usually been considered to be contaminants or colonizers when isolated from respiratory specimens in Korea, where there is a high prevalence of tuberculosis and a low rate of HIV infections. Therefore, there has been few studies on the clinical significance of NTM in a pulmonary infection. In this study, the prevalence of pulmonary NTM and the clinical significance of NTM species in immunocompetent patients were investigated. METHOD: Thirty-five NTM isolates, for which species identification was requested by the treating physicians during 1999 at the Asan Medical Center, were retrospectively analyzed. They were identified to the species level by mycolic acid analysis using high-performance liquid chromatography. The medical records of the patients with the NTM isolates were reviewed to identify those patients who met the American Thoracic Society (ATS)'s criteria for mycobacterial pulmonary infection. Their antimicrobial susceptibility data were compared with the clinical outcomes. RESULTS: The NTM were identified as M. intracellulare (6 isolates), M. avium (5), M. abscessus (5), M. gordonae (5), M. terrae complex (4), M. szulgai (2), M. kansasii (2), M. fortuitum (2), M. peregrinum (1), M. mucogenicum (1), M. celatum (1), and M. chelonae (1). All 35 patients showed clinical symptoms and signs of chronic lung disease, but none had a HIV infections; 16 (45.7%) patients were found to be compatible with a NTM pulmonary infection according to the ATS criteria, 5 and 4 cases were affected with M. intracellulare and M. abscessus, respectively; 8 patients had a history of pulmonary tuberculosis. 13 patients received antimycobacterial therapy for an average of 21 months and 9 patients were treated with second-line drugs. Only 4 patients had improved radiologically. CONCLUSION: A NTM should be considered a potential pathogen of pulmonary infections in immunocompetent patients with chronic pulmonary diseases. Most NTM infections were left untreated for a prolonged period and showed a poor outcome as a result. M. intracellulare and M. abscessus were the two most frequent causes of NTM pulmonary infections in this study. Species identification and antimycobacterial susceptibility tests based on the species are needed for the optimum management of a NTM pulmonary infection in patients.

A Case of Septicemia Caused by Yersinia pseudotuberculosis / 대한임상미생물학회지

Yersinia pseudotuberculosis is a relatively infrequent cause of human infections, mostly as intestinal yersinosis. A septicemic form of Y. pseudotuberculosis infection has been reported only rarely. It is usually seen in patients with underlying disorders such as diabetes, hepatic cirrhosis or iron overload. A 63-year-old man with diabetes mellitus and liver fibrosis was admitted to Asan Medical Center via emergency department because of epigastric pain, fever and watery diarrhea; he was septic. The stool culture did not grow Salmonella, Shigella, or Yersinia. But, in the blood culture Y. pseudotuberculosis grew from one anaerobic vial among two sets of aerobic and anaerobic blood cultures. Serotype of Y. pseudotuberculosis strain was could not be determined because it was a rough type. The isolate was positive in the autoagglutination test and polymerase chain reaction for the virF gene. The serum levels of iron, TIBC and ferritin were within normal range. The patient received ceftriaxone therapy for 3 days and was discharged with a clinical improvement.

Comparison of Perasafe(R) with Cidex(R) for Cidal Activities Against Bacteria, Yeast, Mycobacteria and Bacterial Spores / 병원감염관리

BACKGROUND: Glutaraldehyde is used most commonly as a high-level disinfectant for semicritical patient-care equipments. However, its potential toxicity to healthcare workers and a long exposure time needed to kill mycobacteria can be problematic. Recently, Perasafe(R) (Antec International, UK) has been introduced in the market as a safe and very effective disinfectant. This study was to evaluate the efficacy of Perasafe(R) against not only bacteria and yeast but also mycobacteria and bacterial spores and compare it with glutaraldehyde. MATERIAL AND METHOD: Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Mycobacterium tuberculosis, and Bacillus subtilis were used for the test. Perasafe(R) and Cidex(R) were used at the final concentration of 1.62% and 2.25%, respectively; the disinfectants were neutralized by Tween 80 (0.5%) in the mycobacterial test and by lecithin (0.75%) in all other tests. Bacterial suspensions were made in phosphate buffer with or without fetal bovine serum (1%) to simulate dirty or clean conditions, respectively. The disinfectants were tested at 0, 24 and 48 hr of preparation to check stability. An effective disinfectant activity was defined as a 5 log10 reduction in viable counts. RESULTS: E. coli, S. aureus, P. aeruginosa and C albicans were effectively disinfected in less than 5 min by both Perasafe(R) and Cidex(R) and the both disinfectants remained equally effective under the dirty conditions or at 48 hr of preparation. Perasafe(R) was effective in 1 min against B. subtilis spores compared to Cidex(R) which took 30 min for the same activity. M. tuberculosis was effectively disinfected in 10 min by Perasafe(R) and 20 min by Cidex(R). CONCLUSIONS: Perasafe(R) showed greater tuberculocidal and sporicidal activities than Cidex(R), although both disinfectants were equally effective against common bacterial and yeast pathogens. Perasafe(R) may be an outstanding high-level disinfectant for endoscopes and other semicritical medical equipment.

The Clinical Relevance of Four-Day Blood Cultures with the BACTEC 9240 System / 대한임상병리학회지

BACKGROUND: It is well established that automated blood culture systems require no more than five days of incubation for the detection of the majority of pathogens. It is not clear, however, whether continuous monitoring of blood culture systems also routinely require five days of incubation. This study was conducted to determine the clinical impact of incubating blood cultures for 4 days rather than for 5 days using the BACTEC 9240 blood culture system. METHODS: During the 6-month period from July to November 1998, 22,167 blood cultures were performed. Positive culture sets and the isolates were sorted by times to detection of isolates. Chart reviews were done for isolates detected on day 3 or later to determine whether therapy was changed due to this blood culture result. RESULTS: Of 2,426 isolates (2,319 positive cultures), 2,344 (96.6%) were recovered within 3 days and 52 (2.1%) were recovered on day 4, and 30 (1.2%) on day 5. Chart reviews showed that 21 of the 52 isolates detected on day 4 were considered clinically significant and 10 of those affected the treatment of the patients. On day 5, 5 of the 30 isolates were considered clinically significant and 3 of those affected the treatment. CONCLUSIONS: Four-days rather than a 5-day incubation period reduced culture sensitivity by 1.2% but most of those were clinically irrelevant. These data suggest that the 4-day protocol for the BACTEC 9240 system is adequate for detection of positive blood cultures.

In vitro activities of quinupristin/dalfopristin and eight other antimicrobial agents against 360 clinical isolates from Korea

The emergence of multi-drug resistant gram-positive cocci such as methicillin-resistant (MR) staphylococci, vancomycin-resistant (VR) enterococci, and vancomycin-intermediate resistant S. aureus (VISA) has given new urgency to the development of new antimicrobial agents. One of these is quinupristin/dalfopristin (Q/D). We decided to determine the susceptibility of gram-positive cocci isolated at two university hospitals in Seoul to Q/D and compare the results with eight other antimicrobial agents. We investigated 120 isolates of S. aureus including 49 MRSAs and one VISA, 120 isolates of coagulase negative staphylococci (CNS), 64 E. faecalis and 56 E. faecium, including seven strains of VR E. faecium. Minimum inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) for several antimicrobials, including vancomycin and Q/D, were determined by broth microdilution. All S. aureus including VISA were susceptible to Q/D. Q/D MIC90 for both methicillin-susceptible S. aureus (MSSA) and MRSA was 0.25 g/mL. 49 (87.5%) of 56 E. faecium including six of seven VR E. faecium were susceptible to Q/D. E. faecalis were not susceptible to Q/D (only 1.5% susceptible), but were inhibited by ampicillin (94% susceptible) or vancomycin (95%). CNS was susceptible to Q/D (96% susceptible) and vancomycin (100% susceptible). One of 38 staphylococci and two of 17 E. faecium were tolerant to Q/D. In conclusion, Q/D showed excellent activity against all species of gram-positive cocci including MRSA, VISA, and VR E. faecium except E. faecalis, and may provide a valuable option for the treatment of infections caused by these emerging nosocomial pathogens of gram-positive cocci.

Characteristics of Group B Streptococcal Bacteremia in Non-pregnant Adults and Neonates / 감염

BACKGROUND: Group B streptococci (GBS) are major cause of meningitis and septicemia in neonates and pregnant women, but the importance in non-pregnant adults has not been clearly defined. METHODS: Medical records of all patients with group B streptococcal bacteremia from 1988 to 1997 at Asan Medical Center were reviewed. We compared the clinical and laboratory findings of non-pregnant adults to those of neonates. RESULTS: In a 8-year period there were 41 patients with GBS bacteremia. Thirteen (31.7%) patients were neonates (mean age 14.0+/-11.5 day) and 28 (68.3%) were non-pregnant adults (mean age 52.8+/-13.3 year). Community-acquired infections were 2 cases (15.4%) in the neonates and 7 cases (25.0%) in the non-pregnant adults. In the non-pregnant adults, the most common clinical diagnosis was bacteremia without identified source (15 cases, 53.6%). The others were bone or joint infection (6), urinary tract infection (4), pneumonia (2), skin infection (2), peritonitis (2), and meningitis (1). GBS bacteremia was more common in old age (50 years, 20 cases, 71.4%), the presence of diabetes mellitus (10), solid tumors (10) and liver cirrhosis (10). The mortality rate in non-pregnant adults was 35.7% (10 cases), accounting for 10.7% (3) of deaths related to GBS. In the neonates, early onset infection were 5 cases (38.5%) and late onset infection were 8 (61.5%). The presumed portal of entries were bacteremia without identified focus (5 cases, 38.5%), and meningitis (8, 61.5%). The mortality rate in the neonates was 23.1% (3 cases) and 7.1% (1) related to GBS bacteremia. CONCLUSION: GBS bacteremia is a serious problem not only in the neonates and pregnant women but also in the non-pregnant adults, especially those who are elderly patients with significant underlying diseases.

Clinical Usefulness of Primary Broth Cultures / 대한임상미생물학회지

BACKGROUND: Although enriched broth cultures have been recommended as an adjuvant to the direct plating of tissue and body fluid specimens, the cost-effectiveness of broth cultures has been questioned in regard with the clinical significance of "broth only isolates(BOI)". The purpose of this study was to investigate the usefulness of thioglycollate broth(THIO) cultures. METHODS: We reviewed retrospectively results in the culture specimens of body fluids, tissue biopsies, and puses received during the month of July 1997. All specimens were inoculated into THIO in addition to agar plates. We reviewed the medical records of culture-positive patients to determine the clinical significance and relevance of their isolates. Clinically significant isolates were defined as those for which an appropriate antimicrobial therapy was done except one judged as contaminants by clinicians and clinically relevant isolates as the clinically significant one isolated first. RESULT: Of 2,008 specimens, 512(25.4%) from 365 patients grow 561 isolates 464 plate isolates and 97 BOI. Two hundred eighty nine(62.3%) of the 464 isolates from plate cultures were clinically significant, compared to only 12(12.4%) of 97 BOI (P<0.05). Only four (4.1%) BOI were clinically relevant, including one Pseudomonas aerugiosa from ascites. one Klebsiella pneumoniae and two Staphylococcus aureus from tissue specimens. CONCLUSION: A routine use of enriched broth culture rarely recover clinically relevant isolates. Considering the laboratory and medical costs of the recovery of contaminants and clinically irrelevant isolates, the enrichment broth cultures should be used more selectively.

Identification and Clinical Significance of Kluyvera species / 대한임상병리학회지

BACKGROUND: Kluyvera, a new genus in the family Enterobacteriaceae, has been rarely isolated from clinical specimens and regarded as an opportunistic pathogen. Although there were several case reports in Korea, most of them were reported at a genus level except a case of K. cyrocrescens. We isolated Kluyvera species from seven patients from July 1996 to January 1999. We identified them to species level and investigated their clinical significance. METHODS: The medical records of seven patients were reviewed for demographical findings, underlying diseases, diagnoses, the association of Kluyvera isolates with disease, antibiotic treatments, and clinical outcomes. Eight strains were identified and tested for the antimicrobial susceptibilities by MicroScan Neg Combo type 14 and 21 Panel(Dade Behring, USA). Five of the eight strains had been stored at -70degrees C and were tested for ascorbate fermentation, the ability to grow and ferment glucose at 5degrees C, and the zone of inhibition around carbenicillin and cephalothin. RESULTS: Kluyvera isolates were regarded as true pathogens in six of seven cases including Hickman-catheter associated sepsis(HCAS), empyema, peritonitis, necrotizing cholecystitis, sepsis, and liver abscess although the latter four cases yielded mixed cultures. While three of the six patients had underlying diseases, malignant lymphoma, hepatocellular carcinoma and stomach cancer, other three were previousely healthy. Most of them were improved with an empirical therapy, but Kluyvera species was repeatedly isolated from the HCAS case in spite of the antibiotic treatment; it was cured bacteriologically after the removal of the catheter. The five isolates were all confirmed to be K. ascorbata by positive ascorbate test, and failure to grow at 5degrees C. CONCLUSIONS: Six of the seven cases including three with no underlying diseases, isolates of Kluyvera species were found clinically significant, suggesting that Kluyvera species is potentially pathogenic in healthy individuals as well as compromized hosts. MicroScan system is capable of identifying Kluyvera species at the genus level, but not at the species level. The ascorbate test is simple and useful for differ entiation of K. ascorbata from K. cryocrescens.

Comparison of Murex Candida albicans CA50 with the Germ Tube Test for Presumptive Identification of Candida albicans / 대한임상병리학회지

BACKGROUND: Rapid and reliable identification of Candida albicans becomes more important because the incidence of yeast infections has increased in recent years. Murex C. albicans 50(CA50) assay was developed for rapid and presumptive identification of C. albicans. We evaluated the CA50 assay to identify C. albicans. METHOD: Seventy four yeast isolates from clinical specimens were tested with CA50 and germ tube test. They were identified to species level by API 20C and chlamydospore agar test. RESULT: Of the 74 isolates, 52 were C. albicans and 22 were non-albicans Candida. The sensitivity and specificity for CA50 were 88.5% and 86.4%, respectively. The sensitivity and specificity of the germ tube test using human serum were 88.5% and 90.9% respectively, and those using fetal bovine serum(FBS) were 92.3% and 90.9% respectively. CONCLUSION: CA50 was a rapid and easy-to-perform test, and it was comparable to germ tube test in regard of sensitivity and specificity.

The Value of Superoxidized Water (Cleantop(R)) for Endoscopic Disinfection / 대한소화기내시경학회지

BACKGROUND/AIMS: Conventional disinfectants are expensive, hazardous, and often require long periods of exposure. The aim of this study was to evaluate the effectiveness of a new endoscopic disinfector (Cleantop(R)) that uses superoxidized water (SW) as a disinfectant. METHODS: Immediately after patient examinations, endoscopes were cleaned manually and disinfected with SW for seven minutes. Cultures were taken from valves (swabbing), biopsy channels (rinsing), and biopsy channels after brushing (rinsing). The results were compared with those of other disinfectants tested previously by the same culture methods. RESULTS: Of 12 endoscopes disinfected with SW, disinfection rates were 83.3%, 58.3% and 25% at valves, channels and channels after brushing, respectively. In no instances were more than 100 colony forming units (cfu) of bacteria recovered from each endoscope. SW was similar to peroxygen compound (33.3%, 50%, 50%) and 2% glutaraldehyde (100%, 16.7%, 16.7%) in its disinfectant effect, since 100 or more cfu of bacteria were recovered only from endoscopes disinfected with peroxygen compound. The number of bacterial recovered from endoscopes disinfected with 2% glutaraldehyde was less than 10 cfu. CONCLUSIONS: Disinfection with SW appears to be an effective and time-saving alternative to conventional disinfectants.

Vancomycin-resistant Staphylococcus aureus / 대한임상미생물학회지

Clinical isolates of Staphylococcus aureus with reduced susceptibility to vancomycin(VRSA) have been reported from Japan, the United States and France Although the isolates are considered intermediately resistant according to the National Committee for Clinical Laboratory Standards(NCCLS), they are already a cause of a serious concern in the ever worsening antibiotic crisis of today, because they are all methicillin-resistant S. aureus(MRSA) and they are isolated after prolonged and unsuccessful vancomycin therapy. Furthermore, a study in Japan showed a high prevalence of "hetero-VRSA", MRSA strains that are susceptible to vancomycin according to NCCLS, but contain subpopulation of VRSA at the frequency of > or =10-6 and thus can be converted easily to full-blown VRSA upon exposure to the antibiotic. Recent reports from Seoul showed that hetero-VRSA is also prevalent in Korea. This review is to examine the epidemiology, clinical significance, mechanisms and laboratory detection of vancomycin resistance in clinical isolates of S. aureus; and to summerize infection control guidelines recommended by Centers for Disease Control and Prevention and others for this newly emerging nosocomial pathogen.

Use of Methyl-alpha-D-glucopyranoside Test for Species Identification of Vancomycin Resistant Enterococci / 대한임상미생물학회지

BACKGROUND: The precise identification of Enterococcus gallinarum and E. casseliflavus has assumed additional importance in clinical microbiology due to the intrinsic low-level resistance to vancomycin and the difficulty in differentiating them from E. faecium or E. faecalis, which are frequently found to be clinically significant vancomycin resistant enterococci(VRE). We evaluated the usefulness of Methyl-alpha-D-glucopyranoside(MDG) test for accurate species identification among them. METHODS: A total of 23 enterococci isolates including 18 clinical isolates of VRE from Nov 1997 to Aug 1998 and 5 VRE strains which had previously been reported as E. faecalis (2), E. faecium(2), E. avium(1) carrying vanC were tested for acidification of MDG. MDG test was done using 1% MDG in phenol red broth base and yellow coloration was interpreted as positive after 1 and 2 days of incubation at 35 degrees C. MDG results were compared with species identification by MicroScan Pos Combo type 6 (Dade, US A), motility test, pigment production, and PCR results of vanA, vanB, vanC1, vanC2/C3. RESULTS: Vancomycin resistance of 23 strains were genotyped as 7 strains of vanA, 12 strains of vanC1, 4 strains of vanC2/C3. MicroScan identified 7 vanA VRE as E. faecalis(1) and E. faecium(6), 12 VRE carrying vanC1 as E. faecalis(3), E. faecium(8) and E. avium(1), and 4 VRE carrying vanC2/C3 as E faecalis(3) and E. avium(1). Sixteen vanC VRE strains were all positive for MDG test and only 8(50%) of the 16 strains were motile. Yellow pigment were detected in all 4 vanC2/C3 VRE but only after a careful examination with a prolonged incubation. Seven vanA VRE were all negative in MDG tests, motility test and pigment production. CONCLUSIONS: MicroScan system plus motility and pigment production test was not able to differentiate reliably E. gallinarum and E. casseliflavus from E. faecalis and E. faecium. The MDG test was shown to be superior to motility test in differentiating those from E. faecalis and E. faecium. We conclude that the MDG test should be included for identifcation of VRE.

Vancomycin-resistant Staphylococcus aureus (VRSA): Infection Control Consideration / 병원감염관리

No Abstract available.

A Case of Vancomycin Resistant Enterococci(VRE) Peritonitis in a Patient on CAPD / 대한신장학회잡지

Peritonitis is a major complication of continuous ambulatory peritoneal dialysis and it remains the leading cause of patient droupout. VRE is a very serious pathogen because it is difficult to eradicate due to very limited effective antibiotics and because there is a possibility of transfer of this resistance to other gram-positive organisms including Staphylo-coccus aureus. We experienced a case of CAPD peritonitis by VRE, which was treated with high dose ampicillin and streptomycin without removal of CAPD catheter. We report our experience of CAPD peritonitis caused by VRE and review the literature.

Emergence of Superbacteria, Vancomycin-Resistant Staphylococcus Aureus

No abstract available.

Study for diagnostic efficacy of minibronchoalveolar lavage in the detection of etiologic agents of ventilator-associated pneumonia in patients receiving antibiotics / 결핵

BACKGROUND: Early diagnosis and proper antibiotic treatment are very important in the management of ventilator-associated pneumonia (VAP) because of its high mortality. Bronchoscopy with a protected specimen brush (PSB) has been considered the standard method to isolate the causative organisms of VAP. However, this method burdens consumer economically to purchase a PSB. Another useful method for the diagnosis of VAP is quantitative cultures of aspirated specimens through bronchoscopic bronchoalveolar lavage (BAL), for which the infusion of more than 120 ml of saline has been recommended for adequate sampling of a pulmonary segment. But occasionally it leads to deterioration of the patient's condition. We studied the diagnostic efficacy of minibronchoalveolar lavage (miniBAL), which retrieves only 25 ml of BAL fluid, in the isolation of causative organisms of VAP. METHODS: We included 38 consecutive patients (41 cases) suspected of having VAP on the basis of clinical evidence, who had received antibiotics before the bronchoscopy. The two diagnostic techniques of PSB and miniBAL, which were performed one after another at the same pulmonary segment, were compared prospectively. The cut-off values for quantitative cultures to define causative bacteria of VAP were more than 10(3) colony-forming units (cfu)/ml for PSB and more than 10(4) cfu/ml for BAL. RESULTS: The amount of instilled normal saline required to retrieve 25 ml of BAL fluid was 93 +/- 32 ml (mean +/- SD). The detection rate of causative agents was 46.3% (19/41) with PSB and 43.9% (18/41) with miniBAL. The concordance rate of PSB and miniBAL in the bacterial culture was 85.4% (35/41). Although arterial blood oxygen saturation dropped significantly (p<0.05) during (92 +/- 10 %) and 10 min after (95 +/- 3 %) miniBAL compared with the baseline (97 +/- 3 %), all except 3 cases were within normal ranges. The significantly elevated heart rate during (125 +/- 24/min, p<0.05) miniBAL compared with the baseline (111 +/- 22/min) recovered again in 10 min after (111 +/- 26/min) miniBAL. Transient hypotension was developed during the procedure in two cases. The procedure was stopped in one case due to atrial flutter. CONCLUSION: MiniBAL is a safe and effective technique to detect the causative organisms of VAP.

Mycobacterial Testing in Hospital Laboratories in Korea: Results of a Survey of 40 University or Tertiary-care Hospitals / 대한임상병리학회지

BACKGROUND: Although tuberculosis has often been referred to as diseases of the past, the current prevalence of active tuberculosis is still about 1% and it is 10th leading cause of death in Korea. In United States where tuberculosis has resurged since 1985, mycobacteriology laboratories have been playing a pivotal role in the control of tuberculosis by providing sensitive and rapid diagnostic tests. In Korea, the extent of mycobacteriology services at hospital laboratories has never been documented, although they too should play a central role in controlling tuberculosis. The purpose of this survey is to assess the facility and testing methods of mycobacteriology laboratories and the turnaround times of diagnostic tests. METHOD: In January 1997, the mycobacteriology laboratory of 40 tertiary or university hospitals in Korea were asked to complete a questionnaire involving mycobacterial test methods, test volume, turnaround time (TAT) for AFB stain. TATs for isolation, identification, and susceptibility testing were collected from the laboratory of Asan Medical Center. RESULTS: Of the 40 laboratories participating in this survey, AFB mciroscopy was performed at 40, cultures at 38, and susceptibility tests only at two laboratories. 38 laboratories referred susceptibility tests to other non-hospital laboratories. TATs for AFB microscopy were < or =24 hrs at 34 laboratories and 24-36 hrs in 6 laboratories. Isolation/identification and susceptibility tests for mycobacteria took 40.4+/-13.2 days and 45.7+/-12.4 days, respectively. All but one laboratory used solid media, mostly Ogawa media, for primary culture, and for AFB stain, 37 laboratories were using Ziehl-Neelsen method. For identification of AFB, only 4 laboratories were using a nucleic acid probe method, 18 laboratories biochemical tests, and 16 laboratories no identification test except AFB stain. CONCLUSION: Long TATs were the common and serious problems in mycobacteriology laboratories in Korea. There are urgent needs for optimizing their testing procedures if they were to play a role in the control of tuberculosis in this country. They include introduction of broth media for cultures and susceptibility tests as well as rapid methods for identification.

Evaluation of MicroScan Neg Combo Panel type 21 to Detect ESBL / 대한임상미생물학회지

BACKGROUND: Escherichia coli and Klebsiella pneumoniae resistant to 3rd generation cephalosporin have been reported with increasing frequency in tertiary-care hospital in Korea. MicroScan Neg Combo Panel Type 21 (Type 21) contains a 1 microgram/mL cepfodoxime (POD) in addition to other screen wells containing ceftazidime, cefotaxime, ceftriaxone, and aztreonam, which are designed for detecting extended-spectrum beta-lactamase (ESBL)-producing E. coli and Klebsiella species. We evaluated the Type 21 panel for its ability to detect ESBL. METHODS: From November to December in 1998, 496 E. coli and 326 K. pneumoniae strains isolated from clinical specimens were tested with Type 21 panel The isolates flagged as ESBL producers by the panel were confirmed by the double disk synergy test (DDS). To evaluate the specificity of POD, n-lactamases of 54 E, coli and 20 K. pneumoniae strains that were flagged by, POD only from January to May 1999 were analyzed by isoelectric focusing(IEF). RESULTS: 75/496(15%) E. coli and 68/326(21%) K. pneumoniae were flagged as ESBL producers by Type 21 panel. Of those, 94 isolates including 38/75 (51%) of E. coli and 56/68 (82%) of K. pneumoniae were positive for DDS. Among the 94 ESBL producers, all were detected by POD, 84% by cefotaxime, 85% by ceftazidime, 84% by ceftriaxone, and 86% by aztreonam. The 74 strains that were flagged as ESBL producers by POD screen well only were mostly DDS-negative, cefoxitin- resistant and showed beta-lactamases with pls of 5.4 and 7.6 or no band, which could be interpreted as the presence of TEM-1 or SHV-1 type beta-lactamases and/or basal AmpC beta-lactamases, not ESBL. CONCLUSION: MicroScan Neg Combo Panel Type 21 was able to detect a greater number of ESBL producers by inclusion of POD in its screening well. However, the specificity of POD was compromised by flagging a significant number of DDS negative strains. We conclude that the isolates with reduced susceptibility to 3rd generation cephalosporins as well as POD can be reported as ESBL-producers and those resistant to POD only should be confirmed by DDS.

The Role of Clinical Pathologists in Nosocomial Infection Control in Korea: Challenge in the New Millennium / 대한임상병리학회지

Systemic nosocomial infection control programs were instituted for the first time in Korea by two university hospitals in Seoul in 1991 when full-time infection control nurses were employed. Since then, infection control programs and activities have been expanded to many university hospitals throughout the country, thanks to an increasing awareness of the importance of preventing nosocomial infections by the government, medical and academic communities and citizens' groups. However, progress has been slow. The tow major problems are: 1) the lack of financial incentives for the hospitals to prevent nosocomial infections ; and 2) a shortage of trained professionals, namely, the infection control nurse and the infection control physician. This review is to summerize the components of cost-effective infection control programs, and the current state of and the problems in the infection control in Korea; and to recommend the clinical pathologist a new role as a infection control physician, which will help not only to activate the infection control programs in the country, but also to reduce the financial loss of the hospital caused by nosocomial infections under the prospective payment system based on diagnosis related groups.