BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection ...BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis.展开更多
AIM： To evaluate the accuracy of automated blood cell counters for ascitic polymorphonuclear （PMN） determination for： （1） diagnosis, （2） efficacy of the ongoing antibiotic therapy, and （3） resolution of spon...AIM： To evaluate the accuracy of automated blood cell counters for ascitic polymorphonuclear （PMN） determination for： （1） diagnosis, （2） efficacy of the ongoing antibiotic therapy, and （3） resolution of spontaneous bacterial peritonitis （SBP）. METHODS： One hundred and twelve ascitic fluid samples were collected from 52 consecutive cirrhotic patients, 16 of them with SBP. The agreement between the manual and the automated method for PMN count was assessed. The sensitivity/specificity and the positive/negative predictive value of the automated blood cell counter were also calculated by considering the manual method as the ＂gold standard＂ RESULTS： The mean ＋ SD of the difference between manual and automated measurements was 7.8 4- 58 cells/ram3, while the limits of agreement were ＋124 cells/mm3 [95% confidence interval （CI）： ＋145 to ＋103] and -108 cells/mm3 （95% CI： -87 to -129）. The automated cell counter had a sensitivity of 100% and a specificity of 97.7% in diagnosing SBP, and a sensitivity of 91% and a specificity of 100% for the efficacy of the ongoing antibiotic therapy. The two methods showed a complete agreement for the resolution of infection. CONCLUSION： Automated cell counters not only have a good diagnostic accuracy, but are also very effectivein monitoring the antibiotic treatment in patients with SBP. Because of their quicker performance, they should replace the manual counting for PMN determination in the ascitic fluid of patients with SBP.展开更多
AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of gastroscopes.METHODS:Teflon tubes were incubated in a mixt...AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of gastroscopes.METHODS:Teflon tubes were incubated in a mixture of different detergents and E. coli culture (106 CFU/mL) for 72 h at 15℃,and biofilms on the inner surface of the teflon tubes were analyzed by bacterial count and scanning electron microscopy. To evaluate the clear-ance effect of detergents,after biofilms were formed on the inner surface of Teflon tubes by 72 h lavage with E. coli culture,tubes were lavaged by enzymatic and non-enzymatic detergents at a speed of 250 mL/min,then biofilms on the inner surface were analyzed by bacterial count and scanning electron microscopy.RESULTS:Non-enzymatic detergent had a better inhi-bition function on biofilm formation than enzymatic de-tergent as it reduced bacterial burden by 2.4 log compared with the control samples (P = 0.00). Inhibition function of enzymatic detergent was not significantly different to that of control samples and reduced bac-terial burden by 0.2 log on average (P > 0.05). After lavaging at 250 mL/min for 3 min,no living bacteria were left in the tubes. Scanning electron microscopy observation showed biofi lms became very loose by the high shear force effect. CONCLUSION:Non-enzymatic detergent has a better inhibition effect on biofilm formation at room temperature. High speed pre-lavage and detergents are very important in temporal formed biofilm elimination.展开更多
AIM:To evaluate effective alternative antibiotics in treatment of cefotaxime-resistant spontaneous bacterial peritonitis.METHODS:One hundred cirrhotic patients with spontaneous bacterial peritonitis [ascitic fluid pol...AIM:To evaluate effective alternative antibiotics in treatment of cefotaxime-resistant spontaneous bacterial peritonitis.METHODS:One hundred cirrhotic patients with spontaneous bacterial peritonitis [ascitic fluid polymorphonuclear cell count(PMNLs) ≥ 250 cells/mm 3 at admission] were empirically treated with cefotaxime sodium 2 g/12 h and volume expansion by intravenous human albumin.All patients were subjected to history taking,complete examination,laboratory tests(including a complete blood cell count,prothrombin time,biochemical tests of liver and kidney function,and fresh urine sediment),chest X-ray,a diagnostic abdominal paracentesis,and the sample subjected to total and differential cell count,chemical examination,aerobic and anaerobic cultures.Patients were divided after 2 d by a second ascitic PMNL count into group Ⅰ;patients sensitive to cefotaxime(n = 81),group Ⅱ(n = 19);cases resistant to cefotaxime(less than 25% decrease in ascitic PMNL count).Patients of group Ⅱ were randomly assigned into meropenem(n = 11) or levofloxacin(n = 8) subgroups.All patients performed an end of treatment ascitic PMNL count.Patients were considered improved when:PMNLs decreased to < 250 cells/mm 3,no growth in previously positive culture cases,and improved clinical manifestations with at least 5 d of antibiotic therapy.RESULTS:Age,sex,and Child classes showed no significant difference between group Ⅰ and group Ⅱ.Fever and abdominal pain were the most frequent manifestations and were reported in 82.7% and 80.2% of patients in group Ⅰ and in 94.7% and 84.2% of patients in group Ⅱ,respectively.Patients in group Ⅱ had a more severe ascitic inflammatory response than group Ⅰ and this was demonstrated by more ascitic lactate dehydrogenase(LDH) [median:540 IU/L(range:150-1200 IU/L) vs median:240 IU/L(range:180-500 IU/L),P = 0.000] and PMNL [median:15 000 cell/mm 3(range:957-23 822 cell/mm 3) vs 3400 cell/mm 3(range:695-26 400 cell/mm 3),P = 0.000] counts.Ascitic fluid culture was positive in 32% of cases.Cefotaxime failed in 19% of patients;of these patients,11(100%) responded to meropenem and 6(75%) responded to levofloxacin.Two patients with failed levofloxacin therapy were treated according to the in vitro culture and sensitivity(one case was treated with vancomycin and one case was treated with ampicillin/sulbactam).In group Ⅱ the meropenem subgroup had higher LDH(range:108-860 IU/L vs 120-491 IU/L,P = 0.042) and PMNL counts(range:957-23 822 cell/mm 3 vs 957-15 222 cell/mm 3,P = 0.000) at initiation of the alternative antibiotic therapy;there was no significant difference in the studied parameters between patients responsive to meropenem and patients responsive to levofloxacin at the end of therapy(mean ± SD:316.01 ± 104.03PMNLs/mm 3 vs 265.63 ± 69.61 PMNLs/mm 3,P = 0.307).The isolated organisms found in group Ⅱ were;enterococci,acinetobacter,expanded-spectrum β-lactamase producing Escherichia coli,β-lactamase producing Enterobacter and Staphylococcus aureus.CONCLUSION:Empirical treatment with cefotaxime is effective in 81% of cases;meropenem is effective in cefotaxime-resistant cases.展开更多
AIM： To verify the validity of the International Ascites Club guidelines for treatment of spontaneous bacterial peritonitis （SBP） in clinical practice. METHODS： All SBP episodes occurring in a group of consecutive...AIM： To verify the validity of the International Ascites Club guidelines for treatment of spontaneous bacterial peritonitis （SBP） in clinical practice. METHODS： All SBP episodes occurring in a group of consecutive cirrhotics were managed accordingly and included in the study. SBP was diagnosed when the ascitic fluid polymorphonuclear （PIN） cell count was 〉 250 cells/mm^3, and empirically treated with cefotaxime. RESULTS： Thirty-eight SBP episodes occurred in 32 cirrhotics （22 men/20 women; mean age： 58.6 ＋ 22.2 years）. Prevalence of SBP, in our population, was 27%. Ascitic fluid culture was positive in nine （24%） cases only. Eleven episodes were nosocomial and 71% community-acquired. Treatment with cefotaxime was successful in 59% of cases, while 41% of episodes required a modification of the initial antibiotic therapy because of a less-than 25% decrease in ascitic PMN count at 48 h. Change of antibiotic therapy led to the resolution of infection in 87% of episodes. Among the cases with positive culture, the initial antibiotic therapy with cefotaxime failed at a percentage （44%） similar to that of the whole series. In these cases, the isolated organisms were either resistant or with an inherent insufficient susceptibility to cefotaxime. CONCLUSION： In clinical practice, ascitic PMN count is a valid tool for starting a prompt antibiotic treatment andevaluating its efficacy. The initial treatment with cefotaxime failed more frequently than expected. An increase in healthcare-related infections with antibiotic-resistant pathogens may explain this finding. A different first-line antibiotic treatment should be investigated.展开更多
This paper focuses on the quantitative expression of bacterial regrowth in water distribution system. Considering public health risks of bacterial regrowth,the experiment was performed on a distribution system of sele...This paper focuses on the quantitative expression of bacterial regrowth in water distribution system. Considering public health risks of bacterial regrowth,the experiment was performed on a distribution system of selected area.Physical,chemical,and microbiological parameters such as turbidity,temperature,residual chlorine and pH were measured over a three-month period and correlation analysis was carried out.Combined with principal components analysis(PCA) ,a logistic regression model is developed to predict and diagnose bacterial regrowth and locate the zones with high risks of microbiology in the distribution system.The model gives the probability of bacterial regrowth with the number of heterotrophic plate counts as the binary response variable and three new principal components variables as the explanatory variables.The veracity of the logistic regression model was 90%,which meets the precision requirement of the model.展开更多
Sheep and horse blood are the most commonly used blood for the isolation of microorganisms from human tissue and fluids. However, in many developing countries such as Nigeria, expired human blood from blood banks is s...Sheep and horse blood are the most commonly used blood for the isolation of microorganisms from human tissue and fluids. However, in many developing countries such as Nigeria, expired human blood from blood banks is still used despite the risk of exposure to HIV and other blood-borne infections, because it is easy to obtain. Blood agar made from blood of rams (similar to sheep), cows, chickens and goats, which are very common in Nigeria, were therefore evaluated. The isolation rates, colony size and morphology as well as haemolytic characteristics of common hospital pathogens such as Pseudomonas aeruginosa, Klebsiella pneumonae, Staphylococcus aureus, and Streptococcus spp, were tested on blood agar prepared from the different animal blood types. All reactions were observed at 24 hrs and 48 hrs respectively. Good growth was achieved by all isolates on rabbit, sheep and chicken blood agar though the best growth was achieved on ram blood agar but there was no significant variation in their morphology. There were differences in their abilities to distinguish haemolytic patterns. Beta Haemolytic Streptococci remained the same on all the blood agar, but the haemolysis of Staphylococci aureus and Pseudomonas aeruginosa varied on different media while haemolysis was least consistent on chicken and cow blood agar. Ram blood agar gave the best reactions in terms of good growth rates of organisms, good morphological characterization as well as good haemolytic reactions. Besides, it is easily available and large quantities of blood can be obtained. Despite the good qualities of ram blood agar observed in this study, however, there is a need for it to be tested further for its ability to support more fastidious organisms.展开更多
文摘BACKGROUND Spontaneous bacterial peritonitis(SBP)is one of the most important complications of patients with liver cirrhosis entailing high morbidity and mortality.Making an accurate early diagnosis of this infection is key in the outcome of these patients.The current definition of SBP is based on studies performed more than 40 years ago using a manual technique to count the number of polymorphs in ascitic fluid(AF).There is a lack of data comparing the traditional cell count method with a current automated cell counter.Moreover,current international guidelines do not mention the type of cell count method to be employed and around half of the centers still rely on the traditional manual method.AIM To compare the accuracy of polymorph count on AF to diagnose SBP between the traditional manual cell count method and a modern automated cell counter against SBP cases fulfilling gold standard criteria:Positive AF culture and signs/symptoms of peritonitis.METHODS Retrospective analysis including two cohorts:Cross-sectional(cohort 1)and case-control(cohort 2),of patients with decompensated cirrhosis and ascites.Both cell count methods were conducted simultaneously.Positive SBP cases had a pathogenic bacteria isolated on AF and signs/symptoms of peritonitis.RESULTS A total of 137 cases with 5 positive-SBP,and 85 cases with 33 positive-SBP were included in cohort 1 and 2,respectively.Positive-SBP cases had worse liver function in both cohorts.The automated method showed higher sensitivity than the manual cell count:80%vs 52%,P=0.02,in cohort 2.Both methods showed very good specificity(>95%).The best cutoff using the automated cell counter was polymorph≥0.2 cells×10^(9)/L(equivalent to 200 cells/mm^(3))in AF as it has the higher sensitivity keeping a good specificity.CONCLUSION The automated cell count method should be preferred over the manual method to diagnose SBP because of its higher sensitivity.SBP definition,using the automated method,as polymorph cell count≥0.2 cells×10^(9)/L in AF would need to be considered in patients admitted with decompensated cirrhosis.
文摘AIM： To evaluate the accuracy of automated blood cell counters for ascitic polymorphonuclear （PMN） determination for： （1） diagnosis, （2） efficacy of the ongoing antibiotic therapy, and （3） resolution of spontaneous bacterial peritonitis （SBP）. METHODS： One hundred and twelve ascitic fluid samples were collected from 52 consecutive cirrhotic patients, 16 of them with SBP. The agreement between the manual and the automated method for PMN count was assessed. The sensitivity/specificity and the positive/negative predictive value of the automated blood cell counter were also calculated by considering the manual method as the ＂gold standard＂ RESULTS： The mean ＋ SD of the difference between manual and automated measurements was 7.8 4- 58 cells/ram3, while the limits of agreement were ＋124 cells/mm3 [95% confidence interval （CI）： ＋145 to ＋103] and -108 cells/mm3 （95% CI： -87 to -129）. The automated cell counter had a sensitivity of 100% and a specificity of 97.7% in diagnosing SBP, and a sensitivity of 91% and a specificity of 100% for the efficacy of the ongoing antibiotic therapy. The two methods showed a complete agreement for the resolution of infection. CONCLUSION： Automated cell counters not only have a good diagnostic accuracy, but are also very effectivein monitoring the antibiotic treatment in patients with SBP. Because of their quicker performance, they should replace the manual counting for PMN determination in the ascitic fluid of patients with SBP.
基金Supported by Medical and Health Research Foundation of Zhejiang Province, China, No. 2007B040, 2007B039
文摘AIM:To compare the influence and clearance effect of enzymatic and non-enzymatic detergents against Escherichia coli (E. coli) biofilm on the inner surface of gastroscopes.METHODS:Teflon tubes were incubated in a mixture of different detergents and E. coli culture (106 CFU/mL) for 72 h at 15℃,and biofilms on the inner surface of the teflon tubes were analyzed by bacterial count and scanning electron microscopy. To evaluate the clear-ance effect of detergents,after biofilms were formed on the inner surface of Teflon tubes by 72 h lavage with E. coli culture,tubes were lavaged by enzymatic and non-enzymatic detergents at a speed of 250 mL/min,then biofilms on the inner surface were analyzed by bacterial count and scanning electron microscopy.RESULTS:Non-enzymatic detergent had a better inhi-bition function on biofilm formation than enzymatic de-tergent as it reduced bacterial burden by 2.4 log compared with the control samples (P = 0.00). Inhibition function of enzymatic detergent was not significantly different to that of control samples and reduced bac-terial burden by 0.2 log on average (P > 0.05). After lavaging at 250 mL/min for 3 min,no living bacteria were left in the tubes. Scanning electron microscopy observation showed biofi lms became very loose by the high shear force effect. CONCLUSION:Non-enzymatic detergent has a better inhibition effect on biofilm formation at room temperature. High speed pre-lavage and detergents are very important in temporal formed biofilm elimination.
文摘AIM:To evaluate effective alternative antibiotics in treatment of cefotaxime-resistant spontaneous bacterial peritonitis.METHODS:One hundred cirrhotic patients with spontaneous bacterial peritonitis [ascitic fluid polymorphonuclear cell count(PMNLs) ≥ 250 cells/mm 3 at admission] were empirically treated with cefotaxime sodium 2 g/12 h and volume expansion by intravenous human albumin.All patients were subjected to history taking,complete examination,laboratory tests(including a complete blood cell count,prothrombin time,biochemical tests of liver and kidney function,and fresh urine sediment),chest X-ray,a diagnostic abdominal paracentesis,and the sample subjected to total and differential cell count,chemical examination,aerobic and anaerobic cultures.Patients were divided after 2 d by a second ascitic PMNL count into group Ⅰ;patients sensitive to cefotaxime(n = 81),group Ⅱ(n = 19);cases resistant to cefotaxime(less than 25% decrease in ascitic PMNL count).Patients of group Ⅱ were randomly assigned into meropenem(n = 11) or levofloxacin(n = 8) subgroups.All patients performed an end of treatment ascitic PMNL count.Patients were considered improved when:PMNLs decreased to < 250 cells/mm 3,no growth in previously positive culture cases,and improved clinical manifestations with at least 5 d of antibiotic therapy.RESULTS:Age,sex,and Child classes showed no significant difference between group Ⅰ and group Ⅱ.Fever and abdominal pain were the most frequent manifestations and were reported in 82.7% and 80.2% of patients in group Ⅰ and in 94.7% and 84.2% of patients in group Ⅱ,respectively.Patients in group Ⅱ had a more severe ascitic inflammatory response than group Ⅰ and this was demonstrated by more ascitic lactate dehydrogenase(LDH) [median:540 IU/L(range:150-1200 IU/L) vs median:240 IU/L(range:180-500 IU/L),P = 0.000] and PMNL [median:15 000 cell/mm 3(range:957-23 822 cell/mm 3) vs 3400 cell/mm 3(range:695-26 400 cell/mm 3),P = 0.000] counts.Ascitic fluid culture was positive in 32% of cases.Cefotaxime failed in 19% of patients;of these patients,11(100%) responded to meropenem and 6(75%) responded to levofloxacin.Two patients with failed levofloxacin therapy were treated according to the in vitro culture and sensitivity(one case was treated with vancomycin and one case was treated with ampicillin/sulbactam).In group Ⅱ the meropenem subgroup had higher LDH(range:108-860 IU/L vs 120-491 IU/L,P = 0.042) and PMNL counts(range:957-23 822 cell/mm 3 vs 957-15 222 cell/mm 3,P = 0.000) at initiation of the alternative antibiotic therapy;there was no significant difference in the studied parameters between patients responsive to meropenem and patients responsive to levofloxacin at the end of therapy(mean ± SD:316.01 ± 104.03PMNLs/mm 3 vs 265.63 ± 69.61 PMNLs/mm 3,P = 0.307).The isolated organisms found in group Ⅱ were;enterococci,acinetobacter,expanded-spectrum β-lactamase producing Escherichia coli,β-lactamase producing Enterobacter and Staphylococcus aureus.CONCLUSION:Empirical treatment with cefotaxime is effective in 81% of cases;meropenem is effective in cefotaxime-resistant cases.
文摘AIM： To verify the validity of the International Ascites Club guidelines for treatment of spontaneous bacterial peritonitis （SBP） in clinical practice. METHODS： All SBP episodes occurring in a group of consecutive cirrhotics were managed accordingly and included in the study. SBP was diagnosed when the ascitic fluid polymorphonuclear （PIN） cell count was 〉 250 cells/mm^3, and empirically treated with cefotaxime. RESULTS： Thirty-eight SBP episodes occurred in 32 cirrhotics （22 men/20 women; mean age： 58.6 ＋ 22.2 years）. Prevalence of SBP, in our population, was 27%. Ascitic fluid culture was positive in nine （24%） cases only. Eleven episodes were nosocomial and 71% community-acquired. Treatment with cefotaxime was successful in 59% of cases, while 41% of episodes required a modification of the initial antibiotic therapy because of a less-than 25% decrease in ascitic PMN count at 48 h. Change of antibiotic therapy led to the resolution of infection in 87% of episodes. Among the cases with positive culture, the initial antibiotic therapy with cefotaxime failed at a percentage （44%） similar to that of the whole series. In these cases, the isolated organisms were either resistant or with an inherent insufficient susceptibility to cefotaxime. CONCLUSION： In clinical practice, ascitic PMN count is a valid tool for starting a prompt antibiotic treatment andevaluating its efficacy. The initial treatment with cefotaxime failed more frequently than expected. An increase in healthcare-related infections with antibiotic-resistant pathogens may explain this finding. A different first-line antibiotic treatment should be investigated.
基金Supported by National Natural Science Foundation of China(No.50878140)Project of Water Pollution Control and Repair(No.2008ZX07317-005)
文摘This paper focuses on the quantitative expression of bacterial regrowth in water distribution system. Considering public health risks of bacterial regrowth,the experiment was performed on a distribution system of selected area.Physical,chemical,and microbiological parameters such as turbidity,temperature,residual chlorine and pH were measured over a three-month period and correlation analysis was carried out.Combined with principal components analysis(PCA) ,a logistic regression model is developed to predict and diagnose bacterial regrowth and locate the zones with high risks of microbiology in the distribution system.The model gives the probability of bacterial regrowth with the number of heterotrophic plate counts as the binary response variable and three new principal components variables as the explanatory variables.The veracity of the logistic regression model was 90%,which meets the precision requirement of the model.
文摘Sheep and horse blood are the most commonly used blood for the isolation of microorganisms from human tissue and fluids. However, in many developing countries such as Nigeria, expired human blood from blood banks is still used despite the risk of exposure to HIV and other blood-borne infections, because it is easy to obtain. Blood agar made from blood of rams (similar to sheep), cows, chickens and goats, which are very common in Nigeria, were therefore evaluated. The isolation rates, colony size and morphology as well as haemolytic characteristics of common hospital pathogens such as Pseudomonas aeruginosa, Klebsiella pneumonae, Staphylococcus aureus, and Streptococcus spp, were tested on blood agar prepared from the different animal blood types. All reactions were observed at 24 hrs and 48 hrs respectively. Good growth was achieved by all isolates on rabbit, sheep and chicken blood agar though the best growth was achieved on ram blood agar but there was no significant variation in their morphology. There were differences in their abilities to distinguish haemolytic patterns. Beta Haemolytic Streptococci remained the same on all the blood agar, but the haemolysis of Staphylococci aureus and Pseudomonas aeruginosa varied on different media while haemolysis was least consistent on chicken and cow blood agar. Ram blood agar gave the best reactions in terms of good growth rates of organisms, good morphological characterization as well as good haemolytic reactions. Besides, it is easily available and large quantities of blood can be obtained. Despite the good qualities of ram blood agar observed in this study, however, there is a need for it to be tested further for its ability to support more fastidious organisms.
