Comparison of the detection of anaerobic bacteria in haemoculture systems BACTEC Lytic/10 Anaerobic/F, BacT/Alert FAN Anaerobic and BacT/Alert FN Anaerobic

The purpose of this study is to deal with the problem of anaerobic cultivation of clinical specimens and consider the possibility of using semi-automated blood culture instruments. The Bactec Lytic, BacT/Alert FAN Anaerobic and BacT/Alert FN Anaerobic bottles were inoculated with Bacteriodes fragilis, Clostridium perfringens, Peptostreptococcus anaerobius and Feingoldia magna strains. The times to detection (TTD) for positive bottles were evaluated with reference to the number of inoculated bacteria. Inoculation with the same suspension of equal bacterial strain resulted in shorter TTD values for all the Bactec Lytic bottles as compared with the BacT/Alert FAN Anaerobic or BacT/Alert FN Anaerobic bottles, respectively. Statistically significant differences were recorded (p=0,05) by Bacteroides fragilis and Clostridium perfringens species. Feingoldia magna was submitted to culture in the Bactec Lytic alone. The anaerobic blood culture bottles are deemed acceptable for application in the culture of anaerobc isolates drawn from other samples except for blood (namely when prompt delivery of the sample to the laboratory is impossible and the sample can suffer damage), however, only a limited range of microorganisms can be taken into account for the detection purposes. The Bactec Lytic bottles are more appropriately designed for the detection of anaerobic bacterial species compared to the BacT/Alert FAN Anaerobic and BacT/Alert FN Anaerobic bottles. They achieve faster growth parametres and provide more successful readings of anaerobic bacteria culture and detection.     

Synovial fluid culture: agar plates vs. blood culture bottles for microbiological identification

Clinical Rheumatology - Bacteriological diagnosis of septic arthritis (SA) is complicated. Agar plates are the main culture method and yields 40–60% of positive bacterial detection. Addition...     

Evaluation of the BacT/Alert automated blood culture system for detecting bacteria and measuring their growth kinetics in leucodepleted and non-leucodepleted platelet concentrates

BACKGROUND AND OBJECTIVE: To evaluate the BacT/Alert automated blood culture system for the detection of bacteria in platelet concentrates, and to determine bacterial growth kinetics in leucodepleted and non-leucodepleted units. MATERIALS AND METHODS: Apheresis (Cobe Leucocyte Reduction System [LRS]) and pooled buffy coat-derived (Optipress) platelet concentrates (PCs) were tested. Six organisms were used for spiking the PCs: Clostridium perfringens, Bacillus cereus, Group B Streptococcus, Staphylococcus epidermidis, Staphylococcus aureus and Escherichia coli. Units were inoculated to give a final concentration of approximately equal to 1 and 50 colony-forming units (CFU)/ml. On days 0, 2 and 5, BacT/Alert standard aerobic and anaerobic bottles were inoculated with a 5-ml fill volume and bacteria were enumerated. RESULTS: The BacT/Alert Automated blood culture system gave rapid determination times of spiked units, with all positives detected within 48 h and 98.1% detected within 24 h. In general, as the inoculum concentration increased, the detection time decreased. Rapid growth was obtained with all organisms tested except for B. cereus, which failed to grow on four occasions. Bacterial numbers on day 2 ranged from 10(5) to 10(11) CFU/ml and on day 5 ranged from 10(4) to 10(12) CFU/ml. Growth was not significantly greater in leucodepleted units. CONCLUSIONS: The study confirmed that PCs are an excellent growth medium for bacteria. Rapid and substantial growth was obtained with all organisms under test. Leucodepletion does not appear to enhance bacterial proliferation. The BacT/Alert automated blood culture system could rapidly detect contamination of units. Bacterial screening using an automated blood culture system is therefore a potential option.     

In vitro comparison of fluid blood culture media

Summary Eight fluid blood culture media from different manufacturers were compared with regard to their ability to culture fastidious microorganisms. In turbidity measurements following inoculation with different bacteria, the media differed with respect to the duration of the lag phase and the log phase of bacterial growth. Similar differences were observed with small inocula in original blood culture bottles (commercially available). Fastidious microorganisms grew better in Supplemented Peptone Broth II (Becton-Dickinson), BHI Roche and BHI bioMérieux. Meningococci could only be cultured in four of the eight media tested, and pneumococci in seven of the eight media (with different velocities of growth).Haemophilus influenzae showed the best results after adding blood or IsoVitalex BBL.

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In vitro-Vergleich von flüssigen Blutkultur-Medien

Zusammenfassung Acht flüssige Blutkulturmedien verschiedener Hersteller wurden auf ihre Eignung für anspruchsvolle Keime geprüft. Sie unterschieden sich bei Trübungsmessungen sowohl in der Latenzzeit als auch in den Wachstumsgeschwindigkeiten der eingeimpften Bakterien. Bei geringer Keimeinsaat in kommerziell erhältlichen Original-Blutkulturflaschen wurden ähnliche Unterschiede beobachtet. Am besten geeignet waren Supplemented Peptone Broth II (Becton-Dickinson), BHI Roche und BHI bioMérieux. Meningokokken wuchsen nur in vier von acht geprüften Medien an, Pneumokokken in sieben von acht Medien, jedoch mit unterschiedlicher Geschwindigkeit. BeiHaemophilus influenzae waren die Unterschiede geringer (bei Zusatz von Blut oder IsoVitalex BBL).

     

Inoculation of blood culture bottles with ascitic fluid. Improved detection of spontaneous bacterial peritonitis

The observation that only 42% of the cases of suspected spontaneous bacterial peritonitis at the University of New Mexico, Albuquerque, had positive cultures prompted a change in ascitic fluid culture technique such that a large volume (10 mL in toto) of ascitic fluid was inoculated into blood culture bottles at the bedside. This new method of culture increased the percentage of cases with positive cultures to 91% and decreased the interval between inoculation of the culture and detection of bacterial growth. This is a more sensitive method of culture than the conventional method in detecting spontaneous bacterial peritonitis.     

Biocompatibility of peritoneal dialysis fluid and influence of compositions on peritoneal fibrosis

Conventional peritoneal dialysis fluid (PDF) is a bioincompatible solution because of several components. These unphysiological compositions might contribute to the development of peritoneal fibrosis. In the present overview we summarize the influence of each composition of PDF (acidic pH, high concentration of glucose and glucose degradation products; advanced glycation end-products and lactate) on the peritoneal fibrotic changes in long peritoneal dialysis (PD) patients. We also summarized the report of new approaches to the prevention of peritoneal fibrosis in Japan.     

BacT/Alert 3D系统与罗氏培养基分离分枝杆菌的比较

目的评价BacT/Alert 3D系统从临床标本中分离分枝杆菌的价值。方法收集从2004年12月至2005年4月的临床标本共416份,每份标本接种BacT/Alert 3D系统的同时接种两支改良罗氏培养基和涂片作荧光染色。结果416份临床标本中,共分离出144株分枝杆菌,分离率为34.6%。BacT/Alert 3D系统分离130株,分离率为31.3%,罗氏培养基分离出126株,分离率为30.3%。BacT/Alert 3D系统平均阳性报告时间为是19.9 d,罗氏培养基平均阳性报告时间为26.4 d。BacT/Alert 3D系统的污染率为3.6%,罗氏培养培养基的污染率为5.8%。结论BacT/Alert 3D系统和罗氏培养基联合检测有助于提高检出率和降低污染率。     

BacT／Alert 3D系统与罗氏培养基分离分枝杆菌的比较

目的评价BacT／Alert 3D系统从临床标本中分离分枝杆菌的价值。方法收集从2004年12月至2005年4月的临床标本共416份，每份标本接种BacT／Alert 3D系统的同时接种两支改良罗氏培养基和涂片作荧光染色。结果416份临床标本中，共分离出144株分枝杆菌，分离率为34．6％。BacT／Alert 3D系统分离130株，分离率为31．3％，罗氏培养基分离出126株，分离率为30．3％。BacT／Alert 3D系统平均阳性报告时间为是19．9d，罗氏培养基平均阳性报告时间为26．4d。BacT／Alert 3D系统的污染率为3．6％，罗氏培养培养基的污染率为5．8％。结论BacT／Alert 3D系统和罗氏培养基联合检测有助于提高检出率和降低污染率。     

糖尿病终末期肾病患者透析方式的探讨

目的比较腹膜透析（PD）及血液透析（HD）对糖尿病终末期肾病患者长期预后的影响,以便为临床选取适当治疗方法提供参考。方法将131例糖尿病终末期肾病患者分为HD组（58例）和PD组（73例）,比较两组患者的血液生化指标、生存率和死亡原因。结果两组患者年龄比较无显著性差异,但大于65岁的老年糖尿病患者PD组明显增多（P〈0．01）。透析第1、第2年两组患者死亡率比较无显著性差异,第3、4年PD组死亡率大幅上升,显著高于HD组（P〈0．01）。HD组18例死亡患者中,年龄大于65岁者4例（22．2％）;PD组29例死亡患者中,年龄大于65岁者17例（58．6％）,两组比较有显著性差异（P〈0．01）。HD组死亡主要原因为脑血管病变（占38．9％）,PD组死亡主要原因为感染（占34．5％）。PD组空腹血糖、甘油三酯、胆固醇均高于HD组,两组比较差异有显著性（P〈0．01）。PD组患者血浆白蛋白、血钾明显低于HD组（P〈0．01）。结论糖尿病终末期肾病患者适于PD,但PD组患者2年以上远期生存率明显低于HD组,尤其是大于65岁高龄糖尿病患者PD死亡率明显上升。腹膜透析相对于血液透析仍存在局限性。     

乳酸盐腹膜透析液对人腹膜间皮细胞功能的影响

目的研究乳酸盐腹膜透析液(L-PDF)对人腹膜间皮细胞(HPMC)功能的影响.方法分离HPMC作体外培养,以MTT试验测定HPMC增殖程度;采用ELISA法检测细胞培养液中白细胞介素-8(IL-8)和纤维连接蛋白(FN)的蛋白质水平;逆转录多聚酶链反应检测IL-8mRNA的表达;用Lowry方法检测细胞培养液内总蛋白.结果L-PDF抑制HPMC的增殖,且呈时间依赖关系.L-PDF刺激HPMC后,培养液中IL-8和FN蛋白质水平明显增高,并上调IL-8mRNA的表达.在恢复培养期间,若加用脂多糖(10mg/L)、金黄色葡萄球菌肠毒素(10mg/L)和肿瘤坏死因子-α(TNF-α,10×10     

血液透析和腹膜透析患者死亡原因分析及比较

目的:分析血液净化患者的死亡原因,并比较血液透析(HD)和腹膜透析(PD)患者的死因差异.方法:纳入2005-01-01至2008-12-31期间新进入透析的患者,随访至2009-03-31.结果:460例透析患者中,247例起始采用HD治疗,213例起始采用PD治疗.HD组男性比例和血肌酐显著较高,而PD组基础疾病为高血压肾病比例显著较高,其余基线资料包括透始年龄、体重指数、透析前已知的肾功能不全病程、首次透析治疗前eGFR、平均动脉压、心脑血管事件、Charlson并发症指数等两组间均无明显统计学差异.共87例死亡患者,其中HD患者40例,PD患者47例.HD总体死亡率低于PD患者(0.102和0.171/患者年,P＜0.01).HD 1年死亡率与PD患者无显著差异(0.133和0.196/患者年,P＞0.05),HD 2年死亡率低于PD患者(0.101和0.170/患者年,P＜0.05),HD 3年死亡率低于PD患者(0.101和0.165/患者年,P＜0.05).透析患者的主要死亡原因为心血管疾病(31.0%)、脑血管疾病(21.8%)、感染(16.1%).PD患者心血管病因死亡率显著高于HD患者(0.064和0.022/患者年,P＜0.01),而两组的脑血管疾病、感染、多脏器衰竭和恶性肿瘤导致的死亡率均无显著差异.年龄＜65岁患者中,HD总体死亡率与PD无显著差异,两组患者的心血管疾病、脑血管疾病、感染、多脏器衰竭和恶性肿瘤死亡率均无显著差异.年龄≥65岁患者中,HD总体死亡率低于PD(0.179和0.378/患者年,P＜0.05),PD患者心血管疾病死亡率高于HD患者(0.164和0.004/患者年,P＜0.05),两组患者的脑血管疾病、感染、多脏器衰竭和恶性肿瘤死亡率均尤显著差异.透析龄≤1年患者中,HD总体死亡率与PD患者无显著差异;PD患者多脏器衰竭导致的死亡率显著高于HD患者(0.082和0.000/患者年,P＜0.05),而两组的心血管疾病、脑血管疾病、感染和恶性肿瘤导致的死亡率均无显著差异.透析龄＞1年患者中,HD总体死亡率与PD患者无显著差异;PD患者心血管病因死亡率高于HD患者(0.026和0.006/患者年,P＜0.05),感染导致的死亡率显著高于HD患者(0.013和0.000/患者年,P＜0.05),两组的脑血管疾病、多脏器衰竭、恶性肿瘤导致的死亡率均无显著差异.结论:透析患者最主要的死因为心、脑血管疾病和感染.HD总体死亡率可能低于PD,尤其是心血管疾病和感染导致的死亡率.应该强调透析患者的心脑血管并发症和感染的防治,以提高透析质量,改善长期预后.     

Icodextrin as salvage therapy in peritoneal dialysis patients with refractory fluid overload

Background  

Icodextrin is a high molecular weight, starch-derived glucose polymer, which is capable of inducing sustained ultrafiltration over prolonged (12–16 hour) peritoneal dialysis (PD) dwells. The aim of this study was to evaluate the ability of icodextrin to alleviate refractory, symptomatic fluid overload and prolong technique survival in PD patients.     

腹膜透析患者容量控制对血压的影响

目的探讨限制水钠摄入对腹膜透析患者容量负荷及血压的影响。方法对45例腹膜透析患者,实行限制水钠摄入治疗2个月,测量患者治疗前后的体重、体液容量及血压等相关资料。结果治疗后,33例患者体重减轻(1.9±1.4)kg,细胞外液(ECW)减少(1.20±0.81)L,收缩压(SBP)降低(9.2±14.3)mmHg,差异均有显著性(P<0.01);患者体力、睡眠、饮食等自我感觉改善。另12例患者体重增加(1.2±1.2)kg,ECW增加(0.55±1.09)L,收缩压升高(2.8±10.6)mmHg。治疗前患者收缩压与nECW可能有直线相关关系(r前=0.285,P=0.058);治疗后则显著相关(r后=0.359,P=0.017),还受抗高血压药物治疗的影响(r后=0.334,P=0.027);各因素变化量之间存在直线相关关系。结论腹膜透析患者中,体液容量与血压间存在正相关关系。严格限制患者水钠摄入可以有效控制容量过度负荷,从而控制血压。     

老年持续性腹膜透析患者外周血及腹膜透析流出液辅助性T淋巴细胞亚群分析

目的观察老年维持性腹膜透析患者外周血及腹膜透析流出液中辅助性T细胞亚群的分布情况。方法选取长海医院腹膜透析中心60岁及以上稳定透析16例患者为研究对象（老年实验组）,同一中心稳定透析且一般营养状态、合并症匹配的60岁以下患者16例为对照（对照组）,取外周血及腹膜透析流出液为标本,分离单个核细胞,流式细胞术检测Thelp1、Thelp2、Thelp17及调节性T细胞比例。结果老年实验组外周血中,Th1、Th17细胞比例均降低,分别为（34．2±14．5）％和（1．9±0．6）％,与对照组（38．1±10．7）％,（4．3±2．1）％比较略有降低,但没有统计学意义;Th2、Treg细胞比例咀显升高,分别为（3．2±1．5）％相比于（1．9±1．2）％（P=-0．033）,（7．3±2．9）％相比于（4．3±2．1）％（P=0．028）,差异均有统计学意义。腹膜透析流出液情况类似,除Th2无统计学意义外,Th1、Th17、Treg细胞亚群在老年组中比例分别为（24．2±11．8）％、（3．2±1．8）％和（8．2±4．3）％,对照组为（30．7±19．2）％、（6．7±2．9）％和（5．9±3．9）％,同比变化明显,P值分别为0．031、0．047和O．022,均有统计学意义。结论老年长期连续性不卧床腹膜透析患者机体细胞免疫功能明显下降、宿主免疫功能紊乱,需要通过更细致的营养、疾病评估以明确是否同年龄因素相关。     

Short-term biological effects of a new and less acidic fluid for peritoneal dialysis

BACKGROUND: Conventional peritoneal dialysates are potentially bioincompatible and seem to be a causative factor for peritoneal sclerosis. Recent studies demonstrated that a new type of dialysate has a positive long-term clinical effect on dialysis patients. METHODS: In this study, to elucidate the short-term biological effects of a newly developed dialysate of higher pH on the peritoneal membrane, we assessed macrophage proportions and several markers (inflammatory cytokines, cancer antigen 125 (CA125) and albumin) in spent dialysates before and 2 weeks after the change to the new fluid from a conventional fluid. RESULTS: We found that the use of the new dialysate decreased intraperitoneal levels of inflammatory cytokines, CA125 and albumin associated with the decrease of macrophage populations in dialysis effluents. CONCLUSION: These observations suggest that a new and less acidic fluid reduces pro-inflammatory potential in the peritoneum, and thus affords better preservation of peritoneal membrane integrity in uremic patients on peritoneal dialysis.     

腹膜透析对老年终末期肾脏病病人的血压控制

目的 探讨腹膜透析(PD)对老年终末期肾脏病(ESRD)病人的血压控制情况。方法 50例行PD老年ESRD病人根据年龄分为三组：60～69、70～79和≥80岁，对其血压控制情况进行比较和分析。结果 50例持续不卧床性腹膜透析(CAPD)病人。15例血压正常。5例表现低血压，其余30例均有不同程度的水负荷过多表现。经控制水盐摄入后。7例血压正常。余23例均对饮食控制依从性差。三组病人间的血压控制无显著差异．结论 PD是老年终末期肾脏病(ESRD)患者一个安全有效的治疗方式，但老年PD病人血压控制状况不满意。主要与水负荷过多有关。     

水盐限制对腹膜透析患者血压的影响

目的研究水盐限制对腹膜透析患者血压的影响。方法选择我院肾内科门诊随访超过3个月的高血压腹膜透析患者42例,并对其进行限制水盐摄入治疗3个月,比较治疗前后体重、水肿状况、血压、血钠、白蛋白、血红蛋白水平、24小时尿钠定量、肾小球滤过率及降压药用量。结果水盐限制后,无浮肿的患者增加（P〈0．05）,轻中度浮肿患者减少（P〈0．01）,重度浮肿患者减少为0（P〈0．01）。患者体重明显减轻（P〈0．05）,24小时尿钠排出量降低（P〈0．05）,血压显著下降（P〈0．01）。透析液灌入量前后比较无显著性差异,总出量及超滤量减少,尿量增加（P〈0．05）,高渗透析液用量减少（P〈0．05）,白蛋白及血红蛋白明显升高（P〈0．05）,肾小球滤过率前后比较有显著性差异。降压药用量明显减少（P〈0．05）。结论对高血压腹膜透析患者进行严格水盐限制可明显减轻水肿、降低血压,减少高渗透析液及降压药用量。饮食指导增加了患者的依从性,患者营养状况改善。治疗后未观察到残。肾功能减退的现象。     

Net ultrafiltration in peritoneal dialysis: role of direct fluid absorption into peritoneal tissue.

'Net ultrafiltration' in peritoneal dialysis refers to the difference between the osmotically induced ultrafiltration into the peritoneal cavity and the fluid loss from the cavity during dialysis. Recent research has demonstrated that, during a 3- to 4-hour experimental dialysis, 5-25% of the total fluid loss is via lymphatics and the remaining fluid is absorbed directly into the tissue surrounding the peritoneal cavity. The driving force for this convection into tissue is the hydrostatic pressure gradient between the peritoneal cavity and the tissue, which ranges from 2 to 8 mm Hg during the typical 2-liter dialysis in humans. Because the convection from the cavity occurs during periods of a positive net ultrafiltration, the peritoneum and its underlying tissue cannot be represented as a single membrane but function as a composite of 'tight' and 'loose' membranes. More data on the mechanical properties of the peritoneal tissue space and its response to hydrostatic pressure in the cavity are required before we fully understand fluid transport at the tissue level.     

Net fluid absorption under membrane transport models of peritoneal dialysis.

The effect of oncotic pressure and lymphatic flow on intraperitoneal dialysate volumes in peritoneal dialysis is investigated under each of two membrane transport models: one assuming a homogeneous single-pore membrane and the other a heteroporous three-pore membrane. In both cases, solute and fluid removal are assumed to occur via a mass transport model in which the peritoneum acts like a synthetic membrane separating two well-mixed compartments (body and dialysate). The homoporous mass transport model of Pyle and Popovich and the three-pore model of Rippe et al., although conceptually different, are shown to be equivalent mathematically. This feature allows one to apply the analytical solutions of Vonesh et al. to either model. It also enables one to apply parameter estimates from one model to another; for example, one can apply the lumped sum reflection coefficients of the three-pore model to a homoporous membrane model. A comparison is made between the use of empirically estimated rejection coefficients computed under the homoporous membrane model of Pyle and Popovich versus lumped-sum reflection coefficients calculated in accordance with the three-pore model of Rippe et al. The two models predict similar drain volumes provided the exchange is conducted using glucose as the osmotic agent. However, one does see a significantly different contribution of protein oncotic pressure and lymphatic drainage to fluid absorption under the two sets of osmotic reflection coefficients. Moreover, for a simulated exchange employing an osmotic agent with a molecular weight of 20,000 daltons, the use of reflection coefficients calculated under the three-pore model yields net ultrafiltration values which are more consistent and physiological than results obtained using the empirically estimated rejection coefficients. Since estimates of 'lymphatic flow' will vary according to the quantity and quality of input parameter values (i.e., hydrostatic pressure, protein concentrations, osmotic reflection coefficients), it would be better to label these estimates as the sum of lymphatic and unmodeled net fluid absorption.     

Isolation of Cardiobacterium hominis from the peritoneal fluid of a patient on continuous ambulatory peritoneal dialysis

Cardiobacterium hominis, an uncommon cause of bacterial endocarditis, is rarely implicated in infections outside the vascular system. We report the isolation of C. hominis from the peritoneal fluid of a patient on continuous ambulatory peritoneal dialysis with a presentation suggestive of peritonitis but no evidence of infective endocarditis.