Coronary artery spasm as the probable cause of cardiac arrest immediately after the induction of spinal anesthesia: A case report

A 72-year-old man underwent spinal anesthesia for artificial urinary sphincter placement for urinary incontinence. After the block level was confirmed below T6, 1 g of cefotetan, which had not shown any reaction on skin test, was administered as a prophylactic antibiotic. The patient began complaining of chest discomfort and dyspnea shortly after injection. ST elevation appeared on the electrocardiogram and the patient's pulse could not be palpated. Accordingly, cardiopulmonary resuscitation was performed for 5 minutes; the patient recovered spontaneous circulation. The patient was diagnosed as experienced coronary artery spasm by coronary angiography with spasm test. Because coronary artery spasm can also develop in patients with no history of coronary artery disease and under spinal anesthesia, careful observation, suspicion of coronary artery spasm and prompt response to hemodynamic and electrocardiogram changes are necessary.

Multicenter Study of Antimicrobial Susceptibility of Anaerobic Bacteria in Korea in 2012

BACKGROUND: Periodic monitoring of regional or institutional resistance trends of clinically important anaerobic bacteria is recommended, because the resistance of anaerobic pathogens to antimicrobial drugs and inappropriate therapy are associated with poor clinical outcomes. There has been no multicenter study of clinical anaerobic isolates in Korea. We aimed to determine the antimicrobial resistance patterns of clinically important anaerobes at multiple centers in Korea. METHODS: A total of 268 non-duplicated clinical isolates of anaerobic bacteria were collected from four large medical centers in Korea in 2012. Antimicrobial susceptibility was tested by the agar dilution method according to the CLSI guidelines. The following antimicrobials were tested: piperacillin, piperacillin-tazobactam, cefoxitin, cefotetan, imipenem, meropenem, clindamycin, moxifloxacin, chloramphenicol, metronidazole, and tigecycline. RESULTS: Organisms of the Bacteroides fragilis group were highly susceptible to piperacillin-tazobactam, imipenem, and meropenem, as their resistance rates to these three antimicrobials were lower than 6%. For B. fragilis group isolates and anaerobic gram-positive cocci, the resistance rates to moxifloxacin were 12-25% and 11-13%, respectively. Among B. fragilis group organisms, the resistance rates to tigecycline were 16-17%. Two isolates of Finegoldia magna were non-susceptible to chloramphenicol (minimum inhibitory concentrations of 16-32 mg/L). Resistance patterns were different among the different hospitals. CONCLUSIONS: Piperacillin-tazobactam, cefoxitin, and carbapemems are highly active beta-lactam agents against most of the anaerobes. The resistance rates to moxifloxacin and tigecycline are slightly higher than those in the previous study.

Immunologic Evaluation of Patients with Cefotetan-Induced Anaphylaxis

Cefotetan is a commonly prescribed second-generation cephalosporin that acts against a wide range of bacteria. However, cefotetan-induced hypersensitivity has rarely been reported. We report 2 cases of cefotetan-induced anaphylaxis with immunologic evaluation. The first case was a 70-year-old asthmatic woman who had dyspnea and hypotension during administration of cefotetan, in which high serum-specific IgE to cefotetan-human serum albumin (HSA) conjugate was detected by enzyme-linked immunosorbent assay. The second case was a 63-year-old asthmatic woman who complained of chest tightness and dyspnea during cefotetan infusion, in which high serum-specific IgG1 and IgG4 with no serum specific IgE to cefotetan-HSA conjugate was detected. The basophil activation test using basophils from the patient showed a significant up-regulation of CD63 with the addition of anti-IgG4 antibody compared with that in non-atopic healthy controls. In conclusion, cefotetan can induce anaphylaxis, which may involve both IgE- and IgG4-mediated responses in the pathogenic mechanism.

Delayed Anaphylactic Shock to Intravenous Cefotetan in a Pregnant Woman: A Case Report / 대한구급학회지

Anaphylactic reactions to agents administered intravenously usually occur within minutes. We present an unusual case of a delayed onset anaphylactic shock to intravenous cefotetan in a pregnant woman who underwent an epidural cesarean section. She sustained hypotension, tachycardia, bronchospasm, and rash 90 min after administering intravenous cefotetan. The possibilities of high epidural blocks or amnionic fluid embolisms were excluded by the height of sensory blocks or different presenting symptoms and signs, respectively. Allergic skin tests for exposed materials were performed 6 weeks after discharge and no immediate reactions occurred. However, delayed systemic allergic reactions, such as urticaria, rash, and edema on her face, neck, back, and abdomen, occurred 3 h after skin test to cefotetan.

A simple and sensitive liquid chromatographic technique for the determination of cefotetan disodium in human plasma and its application in a pharmacokinetic study / 华中科技大学学报（医学）（英德文版）

A simple and sensitive liquid chromatographic method was developed for quantification of cefotetan disodium (CTT), a semi-synthetic cephamycin antibiotic, in human plasma. CTT and the internal standard chloramphenicol were extracted from plasma by a simple one-step protein precipitation with 35% (v/v) perchloric acid. Separation was carried out on a reverse-phase C18 column with a mobile phase of acetonitile-water containing 0.5% (v/v) phosphoric acids (20:80, v/v) at a flow rate of 1.0 mL/min. The column effluent was monitored by UV detection at 300 nm. The column temperature was maintained at 40°C. This method demonstrated good linearity in the range of 0.525-300.0 μg/mL, with correlation coefficients greater than 0.99. The limit of quantification (LOQ) was 0.525 μg/mL in human plasma. Intra- and inter-day precisions were less than 6.63% in terms of relative standard deviation (RSD). The accuracy, when expressed by the bias, ranged from 0.57% to 4.04%. The mean extraction recovery of CTT was higher than 40.94%. The method was found to be precise, accurate, and specific for CTT quantitative analysis, and was successfully applied for a pharmacokinetic study of CTT after a single intravenous dose of 1.0 g of CTT in healthy Chinese subjects.

A Prospective, Multicenter, Randomized Trial for Duration of the Prophylactic Antibiotics after Elective Colorectal Surgery: 3 Days versus 5 Days

PURPOSE: The use of prophylactic antibiotics in elective colorectal surgery is essential. Although postoperative prophylactic antibiotics are recommended within 24 hr, the optimal duration of the use of prophylactic antibiotics after colorectal surgery has not yet been fully proven in Korea. The aim of this study was to compare infectious outcomes in elective colorectal cancer surgery between postoperative 3-day antibiotic therapy and 5-day therapy. METHODS: We conducted a multicenter, randomized trial of a 3-day use vs. a 5-day use of the second-generation cephalosporin cefotetan after elective colorectal surgery. The main outcome measures were the incidences of surgical site infection and all other infectious complications within 21 days after surgery. RESULTS: A total of 306 patients were enrolled. Fifty-one patients were excluded because they received additional surgery or dropped out during the study. Two-hundred fifty-five patients were analyzed in this study. The two groups were similar in terms of demographics, ASA score, tumor location, tumor stage, surgical approach (conventional open vs. laparoscopy-assisted vs. robotic-assisted), and type of operation. The incidences of surgical site infection were not significantly different between the 3-day use group (4/130 or 3.1%) and the 5-day use group (3/125 or 2.4%) (P=1.000). Incidences of overall infectious diseases did not differ significantly between the two groups. Postoperatively, both groups had similar values in their white blood cell count, absolute neutrophil count, and C-reactive protein levels. However, the number of patients is small to draw a definite conclusion in this study. CONCLUSION: Three-day cefotetan administration may be not inferior in preventing surgical site infection compared to 5-day antibiotic administration. However, further studies with a large number of patients are needed before a definite conclusion can be drawn.

Cefotetan versus Conventional Triple Antibiotic Prophylaxis in Elective Colorectal Cancer Surgery

This study examined infectious outcomes in elective colorectal cancer surgery between cefotetan alone or conventional triple antibiotics. From January to December 2007, 461 consecutive primary colorectal cancer patients underwent elective surgery. Group A contained 225 patients who received conventional triple antibiotics (cephalosporin, aminoglycoside and metronidazole) for prophylaxis, and group B contained 236 patients who received cefotetan alone for prophylaxis. Treatment failure was defined as the presence of postoperative infection including surgical-site infection (SSI), anastomotic leakage, and pneumonia or urinary tract infection. The two groups were similar in terms of demographics, American Society of Anesthesiologists (ASA) score, tumour location, stage, surgical approach (conventional open vs. laparoscopy-assisted), and type of operation. The treatment failure rates were 3.1% in Group A and 3.4% in Group B (absolute difference, -0.3%; 95% confidence interval [CI], 0.39 to 3.07, P=0.866), with SSI being the most common reason for failure in both groups (2.7% in Group A and 3.0% in Group B [absolute difference, -0.3%; 95% CI, 0.37 to 3.37, P=0.846]). Cefotetan alone is as effective as triple antibiotics for prophylaxis in primary colorectal cancer patients undergoing elective surgery.

Evaluation of the MicroScan NegCombo Panel Type 44 for Detection of Extended-Spectrum beta-Lactamase among Clinical Isolates of Escherichia coli, Klebsiella species, and Proteus mirabilis / 대한진단검사의학회지

BACKGROUND: Accurate and rapid detection of extended-spectrum beta-lactamases (ESBLs) is important in guiding proper antimicrobial therapy for infected patients. We evaluated the performance of MicroScan NegCombo Type 44 panel (Dade Behring, USA), which was developed to confirm ESBL-producing Enterobacteriaceae using ceftazidime/clavulanate and cefotaxime/clavulanate. METHODS: From August 30 to September 20, 2007, 206 non-duplicate clinical isolates, including 106 Escherichia coli, 81 Klebsiella pneumoniae, 11 Klebsiella oxytoca, and 8 Proteus mirabilis were subcultured and tested with Type 32 and Type 44 panels. The results were compared with those of the CLSI phenotypic confirmatory test (CLSI-PCT) and disk approximation test (DAT). Isolates not susceptible to cefotetan or flagged as "Possible ESBL, unable to interpret confirm test (Possible ESBL)" on Type 44 panel were tested with boronic acid disks to confirm AmpC beta-lactamases (AmpC) production. RESULTS: Of the 206 isolates tested, 44 (21.4%) produced ESBL by CLSI-PCT or DAT, including 27 E. coli, 14 K. pneumoniae, 2 K. oxytoca, and 1 P. mirabilis. Thirty-eight isolates flagged as "Confirmed ESBL" on Type 44 panel were all confirmed as ESBL-producers. Of 14 K. pneumoniae flagged as "Possible ESBL", 6 were confirmed as ESBL and AmpC co-producers and 8 as AmpC-producers. CONCLUSIONS: Type 44 panel showed an excellent performance in detecting ESBL-producing E. coli, Klebsiella spp., and P. mirabilis. When flagged as "Confirmed ESBL", no other confirmatory test was necessary to report as ESBL; however, "Possible ESBL" required a differential test for AmpC production.

Microbiological spectrum and antibiotic susceptibility pattern in more than 24-month-old children with urinary tract infection: A6-year retrospective, single center experience / 소아과

PURPOSE: To characterize the pathogens and their antibiotic susceptibilities in more than 24-month-old children with urinary tract infection (UTI) and to study the Escherichia coli antimicrobial susceptibility trend. METHODS: We retrospectively reviewed the record of more than 24-month-old children with UTI between January 2003 and December 2008. Positive results for 1 bacterial species with a colony count of > or =10(5) CFU/mL was considered statistically significant. We analyzed uropathogens and their antibiotic susceptibilities. To investigate E. coli antibiotic susceptibility trend, we compared 2 study periods (group A: 2003-2005 versus group B: 2006-2008) using the chi-square test for trend. RESULTS: In all, 63 bacterial isolates were identified in children with febrile UTI. The most common pathogen was E. coli (77.8%). There was no difference in the resistance patterns of uropathogens during the 2 study periods (P>0.05). Antibiotic susceptibility of the E. coli isolates to aztreonam, cefotetan, cefotaxime, ceftriaxone, cefepime, amikacin, and imipenem was >90% to trimethoprim/sulfamethoxazol, 49% and to ampicillin and ampicillin/sulbactam, 20-25%. Over the 2 study period, the E. coli susceptibilities to most antibiotics did not change: the susceptibility to cefuroxime increased from 74.1% to 95.5% (P=0.046) and that to ciprofloxacin increased from 59.3% to 86.4% (P=0.039). CONCLUSION: Empirical treatment with trimethoprim/sulfamethoxazole, ampicillin, and ampicillin/sulbactam alone appeared to be insufficient in childhood UTI because of the high resistance of E. coli and other gram-negative uropathogens. Antibiotics for empirical therapy should be selected based on the sensitivity and resistance pattern of uropathogens found in a particular region.

Identification of Shiga Toxin-producing E. coli Isolated from Diarrhea Patients and Cattle in Gwangju Area, Korea

Shiga toxin-producing Escherichia coli (STEC) strains are commensal bacteria in cattle and cause food borne disease in human. We analyzed the isolation rate of STEC in stool specimens of patients with diarrhea and in fecal samples of cattle in Gwangju, Korea. STEC strains were detected from 33 (0.19%) out of 17,148 patients with diarrhea while there has been a progressive increase in the incidence rate from 0.07% in 2004 to 0.33% in 2008. We investigated serotypes, shiga toxin genes, and antimicrobial resistance patterns of the 44 STEC isolates from human and cattle sources. The 33 STEC isolates from human belonged to 14 O serotypes including O157, O26 and O111. The 11 isolates from cattle belonged to 11 O serotypes. PCR detection for stx genes showed that 12 (27.3%) isolates carried stx1 genes, 20 (45.5%) possessed stx2 genes, and 12 (27.3%) carried both stx1 and stx2. Of the 33 STEC isolates from human, 25 strains (76%) were resistant to one or more antibiotics. High level of resistance to tetracycline (73%) was most common, followed by ticarcillin and ampicillin (64%). But none of the 33 isolates from human were resistant to amikacin, cefazolin, cefepime, cefotetan, cefotaxime, ciprofloxacin, or imipenem. The 5 strains (45%) of the 11 isolates from cattle were resistant to at least one or three antibiotics but most of the isolates were sensitive to the 16 antibiotics employed in this survey. In conclusion, toxin types and serotypes of STEC isolated from human and cattle were diverse, and non-O157 STEC was also observed to be a greater proportion of STEC isolates. According to a specific comparison solely based on the toxin types and serotypes, most of the STEC strains isolated from cattle feces in Gwangju, Korea showed characteristics different from those isolated from patients. Therefore, laboratory surveillance is required to detect and carefully monitor the potentially hypervirulent STEC not only in human and cattle but also in other animals.

Comparison of 3 Phenotypic-detection Methods for Identifying Plasmid-mediated AmpC beta-lactamase-producing Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis Strains / 대한진단검사의학회지

BACKGROUND: Plasmid-mediated AmpC beta-lactamases (PABLs) have been detected in the strains of Escherichia coli, Klebsiella spp., Proteus mirabilis, and Salmonella spp. PABLs may be difficult to detect and might interfere in the therapeutic and infection-control processes. Although several PABL-detection methods based on phenotypes have been reported, the Clinical and Laboratory Standards Institute currently does not recommend a routine detection method for PABLs. The aim of this study is to compare the performances of 3 phenotypic PABL detection methods. METHODS: Total 276 non-duplicated clinical isolates of E. coli (N=97), K. pneumoniae (N=136), and P. mirabilis (N=43) were collected from 14 hospitals in Korea between April and June 2007 in a non-consecutive and non-random manner. Multiplex PCR was performed to detect the PABL genes. Further, 3 phenotypic detection methods-cephamycin-Hodge test, Tris-EDTA (TE) disk test, and combination-disk test with 3-aminophenylboronic acid (BA)-were performed using cefoxitin and cefotetan disks. RESULTS: PABL genes were detected by multiplex PCR in 122/276 isolates, including 14/97 E. coli, 105/136 K. pneumoniae, and 3/43 P. mirabilis isolates. The combination-disk test with BA showed higher sensitivity (98.4%), specificity (92.2%), and efficiency (96.3%) than the cephamycin-Hodge (76.2%, 96.1%, and 88.6%, respectively) and the TE-disk (80.3%, 91.6%, and 87.9%, respectively) tests. CONCLUSIONS: The combination-disk test with BA is a simple, efficient, and interpretable test that can be applicable in clinical laboratories involved in the detection of PABLs in clinical isolates of E. coli, K. pneumoniae, and P. mirabilis.

Anaphylactic Reaction to Cefotetan during Spinal Anesthesia: A case report / 대한마취과학회지

A 37-year-old male was admitted for a hemorrhoidectomy. He received uneventfully spinal anesthesia for a hemorrhoidectomy. He had no previous history of any allergic tendency. By the request of the general surgeon, a cefotetan was intravenously administered slowly to reduce the incidence of infection. A few minutes later, anaphylactic reaction developed with hypotension, tachycardia, consciousness change and urticaria. After appropriate management, he recovered without any complication.

Anaphylactic Reaction to Cefotetan during Spinal Anesthesia: A case report / 대한마취과학회지

A 37-year-old male was admitted for a hemorrhoidectomy. He received uneventfully spinal anesthesia for a hemorrhoidectomy. He had no previous history of any allergic tendency. By the request of the general surgeon, a cefotetan was intravenously administered slowly to reduce the incidence of infection. A few minutes later, anaphylactic reaction developed with hypotension, tachycardia, consciousness change and urticaria. After appropriate management, he recovered without any complication.

Characterization and Prevalence of Escherichia coli and Klebsiella pneumoniae Isolates Producing an Extended-Spectrum beta-Lactamase from Korean Hospitals / 대한진단검사의학회지

BACKGROUND: The aim of this study was to survey the nationwide susceptibilities of E. coli and K. pneumoniae against third generation cephalosporins and aztreonam in order to determine the prevalence of extended-spectrum beta-lactamase (ESBL)-producers and to characterize genotypes of ESBLs. METHODS: A total of 6, 567 E. coli and 2, 652 K. pneumoniae non-duplicate strains were isolated from 13 hospitals in April to June 2002. Antimicrobial susceptibilities were tested by the disk diffusion method. Twenty isolates of E. coli and 20 K. pneumoniae were collected from each hospital. ESBL production was determined by a double-disk synergy test. The ceftazidime-resistance of the ESBL-producers was transferred to azide-resistant E. coli J53 by conjugation. MICs of beta-lactam antibiotics to transconjugants were determined by the agar dilution method. Searches for blaTEM , blaSHV , blaCTX-M and blaCMY genes in transconjugants were performed by PCR amplification. RESULTS: Eighty-nine percents of E. coli and 71% of K. pneumoniae isolates were susceptible to ceftazidime. Nine percents of E. coli (23/249) and 30% (78/260) of K. pneumoniae isolates showed positive results in the double-disk synergy test. Ceftazidime-resistance of 13 (57%) E. coli and 42 (53%) K. pneumoniae isolates were transferred to E. coli J53 by conjugation. Among 55 transconjugants, 46 strains were resistant to ceftazidime, while only 16 strains were resistant to cefotaxime. Twelve transconjugants were also resistant to cefoxitin and cefotetan. Banding patterns of PCR amplification showed that the blaTEM , blaSHV , blaCTX-M and blaCMY genes were harboured by 44, 39, 4 and 5 transconjugants, respectively. CONCLUSIONS: E. coli and K. pneumoniae isolates producing TEM-, SHV-type, or CTX-M-type ESBLs are wide spread in Korean hospitals. The spread of ESBL genes could compromise the future usefulness of 3rd generation cephalosporins and aztreonam for the treatment of E. coli and K. pneumoniae infections.

Two cases of occupational asthma induced by 7-ACA and ACT / 천식및알레르기

7-ACA(7-aminocephalosporanic acid) and ACT(aminocephalosporanic thiazine) are basic materials for development of 2nd and 3rd generation cephalosporin. Occupational asthmas(OA) induced by these materials have been very rarely reported. We had experienced 2 cases of OA by them. One was 26 year-old male laboratorian involving 7ACA manufacturing directly. The other case was 40 year-old male asthmatics working at the ware house keeping 7ACA and ACT, not directly making these. The result of skin prick test with 55 common inhalant allergens and 7ACA, ACT and several cephalosporins including Cefazolin, Cefuroxime, Ceftazidime, Cefotaxime, Ceftriaxone and Cefotetan. First case revealed positive reactions to 7ACA and Ceftriaxone, but second case, only positive to ACT. In first case, bronchial challenge with 7ACA only showed positive, but in second, those with 7ACA and ACT both showed positive, though negative to 7ACA in skin test.

Comamonas Acidovorans Peritonitis in a CAPD Patient Managed with Preservation of the Catheter / 대한신장학회잡지

To date, only one case of peritonitis with exit site infection in peritoneal dialysis caused by this micro- organism has been reported. In spite of its apparently benign clinical course, which distinguished it from peritonitis caused by Pseudomonas, this peritonitis relapsed and Comamonas could not be eliminated from the peritoneal liquid, probably due to the persistence of the micro-organism in the exit site. Consequently, peritoneal catheter was removed. In this case, a 68-year-old man was admitted with fever, abdominal tenderness and cloudy peritoneal effluent and empirically treated with antibiotics(cefazolin, tobramycin), intraperitoneally(IP) for 7 days. The first culture was positive for Comamonas acidovorans, sensitive to ceftazidime, cefotetan, ceftriaxone, ciprofloxaxin and imipenem and the perotoneal effluent remained cloudy after 7 days. He was treated with ceftazidime IP, oral ciprofloxacin and nystatin for 26 days. 4 days after the antibiotics treatment, the patient was asymptomatic and the cell count of peritoneal effluent was 50 WBC/mm3 with negative culture. 25 days after the treatment, the patient remained asymptomatic and with 5 WBC/mm3 in peritoneal effluent. Consequently, We experienced a case of peritonitis due to Comamonas acidovorans in a patient on CAPD without exit site infection and managed with preservation of the catheter.

Culture-Sensitivity Test and Infectious Complication in Perforated Appendicitis

PURPOSE: The purpose of this study was aimed to disclose main affected organisms in patients with perforated appendicitis and to analyze correlations between culture-sensitivity test and infectious complication. METHODS: In 26 of 421 patients who had undergone appendectomy due to acute appendicitis from April 1996 to March 1999, we performed culture-sensitivity test. The clinical records of these patients were collected and reviewed about clinicopathological features and results of culture-sensitivity test, retrospectively. Culture material was collected in BBL transport media with cotton swab and cultured by MacConkey agar plate. The method of MIC by VITEK was used for sensitivity test. RESULTS: Cultured organisms were E. coli (18 cases), Pseudomonas (4), Enterobacter (2), Enterococcus (1), and Proteus (1). In sensitivity test, sensitive antibiotics against all cultured organism were amikacin, ceftriaxone, imipenem and cefotetan. But ampicillin, sulfametoxazole/trimethoprim and piperacillin were mostly resistant. Infectious complications occurred in 11 of 26 patients (42.3%) and consisted of 9 wound infection and 2 intraabdominal abscess. Especially, 13 of 18 cases in which E. coli were isolated, were resistant to ampicillin. And they had infectious complications statistically more than those who were not resistant to ampicillin (p=0.036). CONCLUSIONS: E. coli was a main organism in perforated appendicitis. In case of ampicillin-resistant E. coli, the patients were susceptible to infectious complication such as wound infection and intraabdominal abscess.

In Vitro Activities of Cefminox against Enterobacteriaceae Species, Haemophilus influenzae, and Methicillin-Susceptible Staphylococcus aureus / 감염

BACKGROUND: Recent clinical isolates of bacteria often produce various beta-lactamases, for example, extended spectrum beta-lactamase (ESBL) by some species of Enterobacteriaceae, TEM beta-lactamase by Haemophilus influenzae, and penicillinase by methicillin-susceptible Staphylococcus aureus (MSSA). Cefminox, a commonly used cephamycin, is stable to various beta-lactamases, but its activity against recent clinical isolates has not been evaluated. The aim of this study was to determine the activities of cefminox against recent clinical isolates of Enterobacteriaceae, H. influenzae, and MSSA. METHODS: The organisms, isolated from Severance Hospital patients during 1997 to 1998, were kept frozen until the test. Antimicrobial susceptibility was determined by the NCCLS agar dilution method. RESULTS: All 30 isolates of Escherichia coli and 90% of 30 Klebsiella pneumoniae isolates were susceptible to cefminox, cefotetan and amikacin. All of the Enterobacter cloacae and Serratia marcescens, and 86% of Citrobacter freundii isolates were susceptible to amikacin. All of the 15 isolates each of Proteus mirabilis, P. vulgaris and Morganella morganii were susceptible to cefminox, cefotetan, cefotaxime, ceftazidime, and aztreonam, while all of the Providencia spp. were susceptible to ceftazidime and aztreonam. All of the 29 H. influenzae isolates were susceptible to cefminox, cefotaxime, and levofloxacin, while all MSSA isolates were susceptible to cefoxitin and cotrimoxazole. CONCLUSION: Cefminox is more active than the other beta-lactams against Enterobacteriaceae including, ESBL- producing E. coli, and K. pneumoniae.

Antimicrobial susceptibility of Klebsiella pneumoniae producing extended-spectrum ß-lactamase (ESBL) isolated in hospitals in Brazil

The prevalence of Klebsiella pneumoniae producing extended-spectrum ß-lactamase (ESBL) has been increasing all over the world. Infections caused by ESBL producing isolates are difficult to detect with current susceptibility test, and are difficult to treat. ESBLs confer resistence to all currently available ß-lactam, except carbapenems. In addition, ESBL, production is usually associated with resistence to other classes of antimicrobial agents such as aminoglycosides and quinolones. The objective of this study was to evaluate in vitro susceptibility patterns of ESBL producing K. pneumoniae isolated in Brazil. Seventy-two strains were tested using E test against 30 antimicrobial agents, inclusing carbapenems, second and third generation cephalosporins, aminoglycosides, quinolones, and some new compounds. The most active compounds (i.e. 100 percent susceptibility) were meropenem (MIC90,0.125µg/mL), imipenem (MIC90,0.25µg/mL), and cefotetan (MIC90,2µg/mL). Ciprofloxacin (MIC90, 1µg/mL, 94 percent susceptibility) and cefepime (MIC90, 6µg/mL, 92 percent susceptibility), were also very active against our collection of ESBL producing K. pneumoniae. None of the six aminoglycosides showed good activity against these strains (16 percent to 41 percent susceptibility) and only 39 percent of the isolates were susceptible to piperacillin/tazobactam. The results of our study indicated that the carbapenems are most active compounds against ESBL producing K.pneumoniae in Brazil, and ciprofloxaxin remains very active against these strains. Cefotetan and cefepine were also very active against ESBL producing K.pneumoniae in Brazil; however, further studies are necessary to evaluate the role of these cephalosporins in the treatment of infections due to ESBL producing strains.

Molecular Epidemiologic Analysis of Nosocomial Escherichia coli Isolates

One hundred and eighteen strains of Escherichia coli isolated from clinical specimens were epidemiologically analyzed for antimicrobial resistance, EcoRI restriction endonuclease analysis, southern hybridization with TEM and SHV probe of conjugative R plasmids. 1. Sixty-two to 73% of E. coli isolates were resistant to ampicillin, carbenicillin, sulfisomidine, and tetracycline, and 20-27% to kanamycin, gentamicin, tobramycin, and nalidixic acid. However more than 93% were susceptible to cephalosporins and all strains were highly susceptible to cefotetan, imipenem, aztreonam, and amikacin. 2. Twelve strains were susceptible to all drugs tested and the multiple resistant strains showed 65 resistance pattern types. 3. Thirty-six resistant strains(34%) transferred R plasmids to E. coli RG488 or RG176 by mixed culture. Fifty-six plasmids with 31 different resistant phenotype were obtained from them. 4. Some of 15 plasmids derived from 10 strains showed identical or similar EcoRI restriction endonuclease digestion patterns, hybridized fragment patterns with TEM probe by southern hybridization, and resistance levels of j3-lactams and aminoglycosides. These results indicate that the epidemic strains or plasmids were present in this hospital and molecular genetic analysis of R plasmids can be used to discriminate clinical isolates of multi- resistant E. coli.