Extended-spectrum cephalosporin compared to cefazolin for treatment of Klebsiella pneumoniae-caused liver abscess

From January 1995 to May 2000, a total of 107 adults with liver abscess due to Klebsiella pneumoniae admitted at a large medical center in northern Taiwan were reviewed. Patients were considered to have received cefazolin or an extended-spectrum cephalosporin if they received at least 3 days of that antibiotic within the first 5 days of hospitalization. Fifty-nine (55.1%) patients received cefazolin, and 48 (44.9%) patients received an extended-spectrum cephalosporin. The demographic data, clinical features, severities of illness, and rates of early drainage for the two groups were comparable. However, the rates of developing complications for the two groups were significantly different (37.3 versus 6.3%, respectively; P < 0.001). Furthermore, six independent factors preventing severe complications following liver abscess due to K. pneumoniae were identified: normal platelet count, alkaline phosphatase less than 300 U/liter, no gas formation in the abscess, APACHE III score less than 40, use of an extended-spectrum cephalosporin, and early drainage. In conclusion, cefazolin therapy may be suboptimal for patients with liver abscess due to K. pneumoniae despite active in vitro susceptibility. Use of an extended-spectrum cephalosporin and early drainage for patients with liver abscess due to K. pneumoniae are suggested.     

Novel, plasmid-encoded, TEM-derived extended-spectrum beta-lactamase in Klebsiella pneumoniae conferring higher resistance to aztreonam than to extended-spectrum cephalosporins.

A clinical isolate of Klebsiella pneumoniae was more resistant to aztreonam than to cefotaxime and ceftazidime. It produced a clavulanate-susceptible beta-lactamase with an isoelectric point of 6.3 which readily hydrolyzed penicillins, cefotaxime, and ceftazidime, but which hydrolyzed aztreonam poorly. The enzyme was encoded by a gene on a 15-kb plasmid; the gene hybridized with an intragenic DNA probe of blaTEM.     

Two sporadic cases of infections due to Klebsiella pneumoniae resistant to expanded-spectrum cephalosporins in Japan

TEM- or SHV-type extended-spectrum β-lactamases (ESBLs) are of clinical concern in Europe and the United States, whereas bacterial strains producing such types of ESBLs have not been reported in Japan. We report here two cases of infection due to Klebsiella pneumoniae resistant to extended-spectrum cephalosporins in Japan. A ceftadizime-resistant K. pneumoniae strain (minimum inhibitory concentration; 32 μg/ml) was isolated transiently from the sputum of an 87-year-old woman with acute myocardial infarction and pneumonia (patient 1). Ceftadizime-susceptible and -resistant (minimum inhibitory concentration; ≥8 μg/ml) K. pneumoniae strains were isolated over a month from the blood, ascites, and feces of a 44-year-old man after bone marrow transplantation for acute lymphoblastic leukemia (patient 2); this patient died of K. pneumoniae sepsis and peritonitis followed by multiple organ failure. These isolates produced penicillinase, which was inhibited by clavulanic acid. A polymerase chain reaction (PCR) study showed that both isolates carried the SHV or LEN genes, but not the TEM, Toho-1, and IMP-1 genes. The pulsed-field gel electrophoresis profile of the strain isolated from patient 1 was genetically distinguishable from the profiles of the strains isolated from patient 2. It appeared that mutation of the β-lactamase gene may have occurred in the body of patient 2, since the genotypes of the ceftadizime-susceptible and -resistant isolates from this patient were identical. Another 12 strains of K. pneumoniae, isolated from other patients in the same wards during the period in which the K. pneumoniae strains were isolated from patients 1 and 2, did not produce ESBLs and showed different genotypes. The results suggest that these isolates of resistant K. pneumoniae did not spread by cross transmission in the hospital and that the two cases were sporadic. Surveillance of these types of resistant bacteria is necessary, since they may well be present in other hospitals in Japan. Although the organisms are suspected to produce SHV-type ESBLs or LEN-1 variant β-lactamases, further studies are necessary to specify the resistance genes. Received: July 6, 1998 / Accepted: December 17, 1998     

A novel virulence gene in Klebsiella pneumoniae strains causing primary liver abscess and septic metastatic complications

Primary Klebsiella pneumoniae liver abscess complicated with metastatic meningitis or endophthalmitis is a globally emerging infectious disease. Its pathogenic mechanism remains unclear. The bacterial virulence factors were explored by comparing clinical isolates. Differences in mucoviscosity were observed between strains that caused primary liver abscess (invasive) and those that did not (noninvasive). Hypermucoviscosity correlated with a high serum resistance and was more prevalent in invasive strains (52/53 vs. 9/52; P < 0.0001). Transposon mutagenesis identified candidate virulence genes. A novel 1.2-kb locus, magA, which encoded a 43-kD outer membrane protein, was significantly more prevalent in invasive strains (52/53 vs. 14/52; P < 0.0001). The wild-type strain produced a mucoviscous exopolysaccharide web, actively proliferated in nonimmune human serum, resisted phagocytosis, and caused liver microabscess and meningitis in mice. However, magA- mutants lost the exopolysaccharide web and became extremely serum sensitive, phagocytosis susceptible, and avirulent to mice. Virulence was restored by complementation using a magA-containing plasmid. We conclude that magA fits molecular Koch's postulates as a virulence gene. Thus, this locus can be used as a marker for the rapid diagnosis and for tracing the source of this emerging infectious disease.     

双肺肺炎克雷伯杆菌感染合并肝脓肿及颅内多发脓毒性脑梗死1例

<正>患者男,71岁,头晕、乏力伴腹痛、腹泻及偶发胸痛不适6天,无发热;既往高血压病史8年。查体:体温38.2℃,脉搏114次/分,呼吸23次/分,血压148/87 mm Hg,左上腹压痛。实验室检查:总胆红素31.30μmol/L,直接胆红素21.00μmol/L,γ-谷氨酰转肽酶89.0 U/L,尿素13.07 mmol/L,肌酐165.2μmol/L,尿酸635.0μmol/L。颅脑及胸、腹部平扫CT:桥脑及双侧放射冠区见多发腔隙性脑梗死;     

Pyogenic liver abscess due to hypervirulent Klebsiella pneumoniae in a 14-year-old boy

A 14-year-old otherwise healthy boy presented with right-sided back pain following high fever. Abdominal computed tomography scan showed a large liver abscess. Klebsiella pneumoniae (KP) was rapidly identified from peripheral blood using the melting temperature mapping (Tm) method, which enables identification of pathogenic microorganisms within four hours after patient sample collection. He was diagnosed with pyogenic liver abscess (PLA) caused by KP on the day of admission. The KP was the hypervirulent (hv) clinical variant (string test positive, serotype K1, sequence type 23, rmpA and magA positive). After intravenous antibiotic therapy and drainage of the abscess, his condition resolved. The highlights of this case report are a healthy child with hypervirulent Klebsiella pneumoniae liver abscess in Japan and the new Tm mapping method for rapid and accurate identification of the pathogenic microorganism.     

肺炎克雷伯菌致多发性肝脓肿患者的加强护理

目的总结肺炎克雷伯菌致多发性肝脓肿患者的成功抢救与加强护理。方法介绍2例危重患者的抢救配合、肝脓肿穿刺置管与手术切开冲洗引流护理、肺炎克雷伯菌感染特点与预防交叉感染、高热护理、用药护理、基础护理、营养支持、心理护理、出院指导等。结果 2例患者经加强护理,完全康复出院。结论肺炎克雷伯菌是常见的多重耐药菌,其引起的多发性肝脓肿患者病情危重、病程长,加强监护、积极处理危及生命的症状和体征、尽早使用敏感抗菌药物、有效的脓肿切开引流、预防交叉感染是抢救成功的关键。     

Primary liver abscess due to CC23-K1 virulent clone of Klebsiella pneumoniae in France

Clin Microbiol Infect 2012; 18: E338-E339 ABSTRACT: Since the mid-1980s, Klebsiella pneumoniae hypermucoviscous isolates have emerged in Taiwan and other Asian countries. We reported the first autochthonous European liver abscess due to an ST57 isolate, which belongs to virulent clonal complex CC23-K1. This case highlights the emergence in France and Europe of hypermucoviscous virulent K.?pneumoniae isolates.     

Proteus mirabilis bloodstream infections: risk factors and treatment outcome related to the expression of extended-spectrum beta-lactamases

Bloodstream infection (BSI) due to Proteus mirabilis strains is a relatively uncommon clinical entity, and its significance has received little attention. This study was initiated to evaluate risk factors and treatment outcome of BSI episodes due to P. mirabilis producing extended-spectrum beta-lactamases (ESBLs). Twenty-five BSI episodes caused by P. mirabilis occurred at our hospital (Ospedale di Circolo e Fondazione Macchi, Varese, Italy) over a 7.5-year period. Phenotypic and molecular methods were used to assess ESBL production. Clinical records of BSI patients were examined retrospectively. Demographic data, underlying diseases (according to McCabe and Jackson classification and Charlson weighted index), risk factors, and treatment outcome were investigated by comparing cases due to ESBL-positive strains to cases due to ESBL-negative strains. Eleven isolates were found to express ESBLs (TEM-52 or TEM-92). The remaining 14 isolates were ESBL negative and were uniformly susceptible to extended-spectrum cephalosporins and monobactams. Comparison of the two groups showed that previous hospitalization in a nursing home (P = 0.04) and use of bladder catheter (P = 0.01) were significant risk factors for infections due to ESBL-positive strains. In addition, cases due to ESBL-positive strains showed a significantly higher mortality attributable to BSI (P = 0.04). BSI cases due to ESBL-negative isolates uniformly responded to therapy, whereas 5/11 cases due to ESBL-positive isolates failed to respond (P < 0.01). Use of carbapenems was associated with complete response independently of ESBL production. Therapeutic failure and mortality may occur in BSI episodes caused by ESBL-positive P. mirabilis isolates. Thus, recognition of ESBL-positive strains appears to be critical for the clinical management of patients with systemic P. mirabilis infections.     

Emerging K1 serotype Klebsiella pneumoniae primary liver abscess: three cases presenting to a single university hospital in Norway

Community‐acquired Klebsiella pneumoniae primary liver abscess (KLA) has been emerging worldwide over the past two decades and with high incidence in Asia. The presence of specific virulence characteristics is a risk factor for a syndrome with metastatic complications. This report signals an increasing emergence in Northern Europe.     

Bloodstream infections due to extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae: risk factors for mortality and treatment outcome, with special emphasis on antimicrobial therapy

This study was conducted to evaluate risk factors for mortality and treatment outcome of bloodstream infections due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EK). ESBL production in stored K. pneumoniae and E. coli blood isolates from Jan 1998 to Dec 2002 was phenotypically determined according to NCCLS guidelines and/or the double-disk synergy test. A total of 133 patients with ESBL-EK bacteremia, including 66 patients with ESBL-producing K. pneumoniae and 67 with ESBL-producing E. coli, were enrolled. The overall 30-day mortality rate was 25.6% (34 of 133). Independent risk factors for mortality were severe sepsis, peritonitis, neutropenia, increasing Acute Physiology and Chronic Health Evaluation II score, and administration of broad-spectrum cephalosporin as definitive antimicrobial therapy (P < 0.05 for each of these risk factors). In 117 of the 133 patients, excluding 16 patients who died within 3 days after blood culture sample acquisition, the 30-day mortality rates according to definitive antibiotics were as follows: carbapenem, 12.9% (8 of 62); ciprofloxacin, 10.3% (3 of 29); and others, such as cephalosporin or an aminoglycoside, 26.9% (7 of 26). When patients who received appropriate definitive antibiotics, such as carbapenem or ciprofloxacin, were evaluated, mortality in patients receiving inappropriate empirical antimicrobial therapy was found not to be significantly higher than mortality in those receiving appropriate empirical antimicrobial therapy (18.9 versus 15.5%; P = 0.666). Carbapenem and ciprofloxacin were the most effective antibiotics in antimicrobial therapy for ESBL-EK bacteremia. A delay in appropriate definitive antimicrobial therapy was not associated with higher mortality if antimicrobial therapy was adjusted appropriately according to the susceptibility results. Our data suggest that more prudent use of carbapenem as empirical antibiotic may be reasonable.     

ICU护士对中心静脉导管相关性感染集束干预策略认知状况的调查研究

目的 了解ICU护士对中心静脉导管相关性感染集束干预策略(CLB)认知状况及影响因素.方法 采用方便采样方法,应用自行设计的结构式调查问卷,对枣庄市2所三甲综合医院156名ICU护士进行问卷调查,并对结果进行分析.结果 ICU护士对中心静脉导管相关性感染集束干预策略认知平均得分为40.87±1.35(满分50分),行为平均得分为30.98±2.56(满分40分).影响其认知的因素有科室、学历、护士类别、ICU工作年限.阻碍ICU护士实施中心静脉导管集束干预策略行为的主要因素是“缺乏中心静脉置管引起导管相关性感染(CRBSI)相关知识的培训教育、科室没有制定预防CRBSI集束干预策略、科室没有中心静脉导管(CVC)标准化操作和维护流程、对CRBSI集束干预策略不熟悉、科室无CVC准入制度、无CVC护理记录制度、无预防CRBSI的教育墙报或操作图片强化学习和提醒”七个方面.结论 医院应加强ICU护士有关导管相关性感染集束干预策略知识的培训和教育;逐步完善相关的护理指南和操作规范;培养ICU专科护理人才,确保有效落实中心静脉导管相关性感染集束干预策略,有效降低导管相关性感染的发生率.     

Redefining the HIV-infectious window period in the chimpanzee model: evidence to suggest that viral nucleic acid testing can prevent blood-borne transmission

BACKGROUND: Although it is rare, blood-transmitted HIV infection can occur when a donor presents in the window period between HIV-1 exposure and the first appearance of detectable p24 antigen. STUDY DESIGN AND METHODS: To study this seronegative window period, a chimpanzee (X034) was inoculated with 38 median tissue culture infective doses of HIV-1 IIIB; serum and peripheral blood mononuclear cells were obtained one to two times per week for 12 weeks and then biweekly for 12 weeks. Infectivity was monitored by the detection of serum HIV RNA, cell-associated HIV DNA, p24 antigen, and anti-HIV and by co-culture methods. RESULTS: No HIV markers were noted until 5 weeks after inoculation, at which time virus was isolated and HIV RNA and DNA were detected in plasma and cells, respectively. Anti-HIV and HIV p24 antigen were not present until 8 weeks after inoculation. Plasma and cells obtained from Chimpanzee X034 3 or 4 weeks after exposure were then sequentially inoculated into a second chimpanzee (X176); no HIV infection was observed in this animal during serial follow-up for 24 weeks after each inoculation. In contrast, when the fifth-week HIV-1 RNA- and DNA-positive sample was inoculated, Chimpanzee X176 was unequivocally infected with HIV-1. CONCLUSIONS: Nucleic acid testing narrowed the seronegative window by 3 weeks (37%). More important, there was no demonstrable infectivity in either plasma or peripheral blood mononuclear cells obtained before molecular markers were detectable.This suggests that the infectious window may be considerably shorter than the total window as measured from exposure and that nucleic acid testing might not only shorten the seronegative window, but totally prevent transfusion-transmitted HIV infection.     

Direct evidence that decreased serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in sickle cell disease is related to antibody deficiency.

Two approaches were used to demonstrate that reduction in serum opsonization of Streptococcus pneumoniae via the alternative complement pathway in children with sickle cell disease is related to a deficiency of antibodies to pneumococcal capsular polysaccharide. First, opsonization of S. pneumoniae mediated by the alternative pathway in patients' sera was restored to normal by addition of the purified IgG or IgM fraction of goat antiserum to capsular polysaccharide of the homologous serotype. Secondly, IgG antibody titers to capsular polysaccharide in patients' sera correlated significantly with alternative pathway-mediated opsonization; the correlation between titers of IgM anticapsular antibodies and opsonization approached statistical significance. The sum of the IgG and IgM anticapsular antibody titers correlated most significantly with opsonization. Our results suggest that reduction in alternative pathway-mediated opsonization in sera from children with sickle cell disease is related to low levels of both IgG and IgM anticapsular antibodies.