Validation of automated blood cell counter for the determination of polymorphonuclear cell count in the ascitic fluid of cirrhotic patients with or without spontaneous bacterial peritonitis

Ascitic calprotectin for the diagnosis of spontaneous bacterial peritonitis: a systematic review and meta-analysis

Calprotectin is a promising diagnostic biomarker for spontaneous bacterial peritonitis (SBP) among cirrhotic patients, but published studies report a wide variation of its diagnostic accuracy. We systematically searched six databases for eligible studies (i.e., all original studies that reported ascitic calprotectin as a diagnostic marker for SBP in cirrhotic patients), and assessed their quality with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. We calculated the pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), and diagnostic odds ratio (DOR) using the bivariate mixed-effect model. We constructed the summary receiver operating characteristic and determined the area under the curve (AUC). We registered the study protocol in PROSPERO (CRD42019125476). Our search retrieved 102 studies, of which 10 were included in the analysis. The overall risk of bias of these studies ranged from low to moderate. There was no heterogeneity from the threshold effect (Spearman correlation coefficient = 0.100, P value = 0.770). The pooled estimates [95% confidence intervals (CIs)] for ascitic calprotectin were as follows: sensitivity 0.91 (95% CI: 0.88-0.94), specificity 0.87 (95% CI: 0.68-0.96), PLR 7.18 (95% CI: 2.52-20.43), NLR 0.10 (95% CI: 0.07-0.15), DOR 71.91 (95% CI: 19.42-266.34), and AUC 0.92 (95% CI: 0.90-0.94). The sensitivity analysis did not detect outliers, and the model had a robust goodness of fit. There was no significant publication bias detected (Deeks test of asymmetry, P value = 0.79). Ascitic calprotectin is a promising diagnostic biomarker for SBP in cirrhotic patients.

Cytological examination of cerebrospinal fluid: Sysmex UF-1000i versus optical microscopy

We evaluated the body fluid module on Sysmex UF-1000i (UF-1000i-BF) for analysis of white blood cell (WBC) and red blood cell (RBC) in cerebrospinal fluid. We collected 93 cerebrospinal fluid samples and compared the results of the UF-1000i-BF mode with the Fast-Read 102 disposable counting cell. Results shows a good correlation between the UF-1000i and the microscopic examination. The concordance percentage is 99.06% for white blood cells and 85.18% for red blood cells. The UF-1000i-BF mode offers rapid and reliable total WBC and RBC counts for initial screening of cerebrospinal fluid, and can improve the workflow in a routine laboratory.

[Spontaneous Bacterial Peritonitis]

Spontaneous bacterial peritonitis (SBP) is defined as bacterial infections that occur in patients with cirrhosis and ascites without any significant intraperitoneal infection, accounting for approximately 10-30% of bacterial infections in hospitalized patients. SBP develops in patients with liver cirrhosis because bacterial translocations are increased by changes in the intestinal bacteria and mucosal barriers. In addition, the decreased host immune response cannot remove the bacteria and their products. The most common cause of SBP is Gram-negative bacteria, such as Escherichia coli and Klebsiella species, and infections by Gram-positive bacteria are increasing. SBP is diagnosed by the presence of >250 polymorphonuclear leukocyte/mm³ in ascites after paracentesis. If SBP is diagnosed, empirical antibiotic therapy should be started immediately. Empirical antibiotic treatment should distinguish between community acquired infections and nosocomial infections. Cirrhotic patients with gastrointestinal bleeding or low ascitic protein concentrations should consider primary prevention and those who recover from SBP should consider secondary prevention. This review describes the pathophysiology, diagnosis, treatment, and prevention of SBP.

Ascitic fluid polymorphic nuclear cell count impacts on outcome of cirrhotic patients with ascites

Background

Spontaneous bacterial peritonitis (SBP) is defined as an ascitic polymorphonuclear cell count (A-PMN) > 250 cells/µl.

Objective

We aimed to investigate the prognostic value of ascitic fluid cell counts in patients without SBP.

Patients and methods

A total of 178 patients were included and stratified by ascitic cell counts at index paracentesis: A-LEUK-low (<250/µl), A-LEUK-intermediate (250-500/µl) and A-LEUK-SBP (>500/µl) for leukocytes; A-PMN-low (<125/µl), A-PMN-intermediate (125-250/µl) and A-PMN-SBP (>250/µl) for PMN cells.

Results

One-year mortality was comparable between group A-LEUK-SBP (53.9%) and patients with subclinical cell counts (34.5% for A-LEUK-low, 43.5% for A-LEUK-intermediate, log-rank p = 0.547). However, we observed an increase in one-year mortality already in group A-PMN-intermediate with 75% and A-PMN-SBP with 80.9% (vs 40.5% for A-PMN-low, log-rank p = 0.016).Importantly, increases of A-PMN cell counts between two paracenteses were associated with increased mortality: per 100 cells/µl increase of absolute A-PMN cell count: hazard ratio (HR): 1.03 (95% confidence interval (CI): 1.01-1.06), p = 0.005; per 5% increase of relative PMN cell count: HR: 1.15 (95% CI: 1.06-1.26), p = 0.001.

Conclusion

Patients with PMN cell counts of 125-250/µl are at high risk for mortality, which was very similar to SBP patients with PMN cell counts >250/µl. This highlights the need for preventive strategies. The prognostic value of changes in relative ascitic PMN cell counts should be evaluated in future studies.

Automated low-flow ascites pump in a real-world setting: complications and outcomes

BACKGROUND AND AIMS

The aim of this study was to investigate the Alfapump, an automated low-flow pump system for the treatment of refractory ascites (RA) as an alternative for repeated large-volume paracentesis in patients with contraindication for placement of a transjugular intrahepatic portosystemic shunt (TIPS) or liver transplantation.

MATERIALS AND METHODS

In 21 consecutive patients with RA and contraindication for a placement of a TIPS, the Alfapump was implanted at Hannover Medical School between December 2012 and May 2016. Repeated laboratory, clinical, and microbiology data were collected and analyzed to assess the outcome of patients with an Alfapump. Half of the patients received a modified peritoneal catheter.

RESULTS

Twenty-one patients with RA in end-stage liver disease and with a contraindication to TIPS placement received the Alfapump. Diuretic dosages were significantly reduced, and the number of paracentesis declined from 2.3±2.7 to 0 per week. Using the Alfapump, kidney function and serum sodium remained stable. Likewise, serum albumin remained stable in the absence of albumin infusions. Thirty-three complications (dislocation and/or blockade of the catheter, infection, pump dysfunction) related to the Alfapump were observed in 15 of 21 patients (71.4%), and 21 surgical interventions were needed in 15 patients (71.4%, 1-3 interventions per patient). A new peritoneal catheter system could significantly reduce blockage of the peritoneal catheter.

CONCLUSION

The Alfapump is an effective treatment in patients with RA. However, a high rate of complications were observed, which could be reduced with a modified peritoneal catheter.

Home-based drainage of refractory ascites by a permanent-tunneled peritoneal catheter can safely replace large-volume paracentesis

BACKGROUND AND AIM

Refractory ascites has a poor prognosis. Recurrent large-volume paracentesis is the current standard of care; however, it results in circulatory dysfunction and renal dysfunction, and hospitalization is commonly required. Transjugular intrahepatic portosystemic shunt placement is not an option in a substantial number of patients because of contraindications. The placement of a tunneled peritoneal drainage catheter has been shown to be effective in patients with malignant ascites. However, data in patients with nonmalignant refractory ascites are rare.

PATIENTS AND METHODS

We followed 24 consecutive patients in whom tunneled peritoneal drainage catheters were placed in the Endoscopy Unit at Hannover Medical School between June 2013 and December 2014.

RESULTS

Catheters were placed in 24 patients with refractory ascites in end-stage liver disease and with a contraindication to transjugular intrahepatic portosystemic shunt placement. Placement was technically successful in all patients. The dosage of diuretics could be reduced significantly. The number of paracentesis decreased from 2.2±1 to 0 per week, although the volume of daily ascites removal remained stable (2 l). Despite frequent drainage of ascites, kidney function, serum sodium, and serum albumin remained stable. Seven adverse events occurred in six (25%) patients. Five patients listed for liver transplantation underwent successful transplantation without a negative impact.

CONCLUSION

The tunneled peritoneal drainage catheter placement is a viable and effective treatment alternative in patients with refractory ascites because of end-stage liver disease, reducing diuretic intake and the need for paracentesis. The procedure avoids hyponatremia, worsening kidney function, and albumin infusions without an increased risk of spontaneous bacterial peritonitis.

A Real-World Evaluation of Repeat Paracentesis-guided Management of Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a common infection in cirrhosis associated with high mortality. More than 20% of patients with SBP do not respond to initial antibiotics. Guidelines differ in recommendations to repeat paracentesis (retap) to confirm antibiotic efficacy. We aim to evaluate the effect of retap-guided management of SBP on antibiotic escalation and 30-day transplant-free survival.

MATERIALS AND METHODS

Retrospective cohort study of cirrhotic patients with SBP admitted to a single transplant center from 2010 to 2014. Patients were divided into 2 groups: retap-guided management versus no retap. Prevalence of initial antibiotic treatment failure, defined as <25% decrease in ascitic polymorphonuclear cells, and factors associated with treatment failure, antibiotic escalation and 30-day transplant-free survival were evaluated.

RESULTS

Out of 210 patients, 146 (age 58, 74% male, mean model for end-stage liver disease score, 25) had retap and treatment failure was noted in 28 (22%). Gram-positive bacteria accounted for 44% of all positive cultures and third-generation cepahalosporin resistance was noted in 23%. Thirty-day transplant-free survival was 72% and 62% in retap and control groups, respectively (P=0.07). Treatment failure independently doubled the 30-day mortality rate (hazard ratio: 2.15, 1.03 to 4.50, P=0.04). After adjusting for age, model for end-stage liver disease and nosocomial infection, retap-guided management was not associated with improved survival (P=0.34).

CONCLUSIONS

The prevalence of initial treatment failure is high (22%) in patients with SBP and doubles the 30-day mortality risk, supporting recommendations to retap all patients with SBP.

Detection of molecular bacterascites in decompensated cirrhosis defines a risk with decreased survival

BACKGROUND

The prognostic relevance of bacterial DNA (bactDNA) detection in ascitic fluid of patients with cirrhosis is still under debate. Using quantitative real-time PCR with broad-range primers targeting the V3 and V4 variable region of the 16S rRNA gene, we measured bactDNA concentrations in patients with and without leukocytic ascites and evaluated the impact on short-term survival.

PATIENTS AND METHODS

Ascites samples from 173 patients with decompensated cirrhosis were consecutively collected between February 2011 and December 2012. BactDNA-positive ascites samples were sequenced and chromatograms were identified using RipSeq. Clinical data collection and survival analyses were carried out retrospectively and correlated with ascites bactDNA levels.

RESULTS

BactDNA was detected qualitatively with a similar frequency in both nonleukocytic and leukocytic ascites [40% (57/144) and 43.5% (10/23), respectively; P=0.724]. However, the median bactDNA level was significantly higher in leukocytic ascites than in nonleukocytic ascites (1.2×10 vs. 5.7×10 copies/ml; P=0.008). Patients' survival was associated significantly with bactDNA level. The 30-day and 180-day survival was reduced if bactDNA was above the quantification limit of 520 copies/ml (84 and 63% vs. 72 and 43%, respectively; P<0.05) and worst if bactDNA was above 5000 copies/ml. The bacterial spectrum was dominated by Gram-positive strains as shown by direct sequencing.

CONCLUSION

BactDNA quantification in ascitic fluid samples using culture-independent 16S rRNA gene-based methods seems to be an interesting approach to identify patients at risk of reduced survival. Our study warrants further evaluation of antibiotic treatment in patients with molecular bacterascites.

Diagnostic Value of Leukocyte Esterase Test Strip Reagents for Rapid Clinical Diagnosis of Spontaneous Bacterial Peritonitis in Patients Admitted to Hospital Emergency Departments in Iran

Background:

Spontaneous bacterial peritonitis (SBP) is a common and important clinical problem and is life-threatening in decompensated liver disease. Ascites fluid test by leukocyte esterase test strip has been recently proposed as an effective and rapid method to diagnose SBP in patients with cirrhosis.

Objectives:

This study aimed to evaluate sensitivity and specificity of leukocyte esterase test strip in the diagnosis of SBP.

Patients and Methods:

The population of this research was all patients with cirrhosis and ascites admitted to the emergency room at Imam Reza (AS) hospital, Mashhad. A written consent was taken for inclusion in the study. 50 mL ascites sample was taken from all patients for use in a urine test strip (LER) (Urine Test Strips Convergys®Urine Matrix 11). The patient’s ascites samples were evaluated for cell counting. Positive dipstick test for LER in this study considered as grade 3 +. The values of WBC > 500 cell/mm³ or PMN > 250 cell/mm³ considered as positive result of the gold standard method for the diagnosis of SBP.

Results:

In this study, 100 patients with ascites due to cirrhosis, with an average age of 38.9 ± 6.54 years were evaluated. Twenty cases had positive results, of whom 17 cases were also detected based on the standard diagnostic criteria and other three cases were healthy individuals. Thus, sensitivity, specificity, positive and negative predictive values, and accuracy of the method were 95%, 96.3%, 85%, 97.5% and 95%, respectively.

Conclusions:

The use of leukocyte esterase urine dipstick test can be a quick and easy method in early diagnosis of SBP to start the treatment until preparation of SBP-cell count results.

[Spontaneous bacterial peritonitis in patients with cirrhosis]

Spontaneous bacterial peritonitis (SBP) is a severe complication occurring in patients with cirrhosis, and is associated with high mortality. Liver transplantation should be considered after a first episode of SBP. Gram-negative bacilli are the major cause of SBP, however there is an increasing trend of Gram-positive cocci related SBP. Management includes empirical antibiotic treatment and albumin infusion. The choice of antibiotics depends on the site of acquisition (community-acquired vs nosocomial or health-care associated infection) and local resistance profile, due to the emergence of drug-resistant bacteria. Secondary prophylaxis is recommended after resolution of SBP and reduces recurrence and mortality. Primary prophylaxis in patients with low protein ascites (<15 g/L) should be restricted to patients with severe cirrhosis awaiting for liver transplantation.

Bacterial meningitis in children under 15 years of age in Nepal

BACKGROUND

Bacterial meningitis in children is a life-threatening problem resulting in severe morbidity and mortality. For the prompt initiation of antibacterial therapy, rapid and reliable diagnostic methods are of utmost importance. Therefore, this study was designed to find out the rate of bacterial pathogens of meningitis from suspected cases by performing conventional methods and latex agglutination.

METHODS

A descriptive type of study was carried out from May 2012 to April 2013. Cerebrospinal fluid (CSF) specimens from 252 suspected cases of meningitis were subjected for Gram staining, bacterial culture and latex agglutination test. The identification of growth of bacteria was done following standard microbiological methods recommended by American Society for Microbiology. Antibiotic sensitivity testing was done by modified Kirby-Bauer disk diffusion method.

RESULTS

From the total 252 suspected cases, 7.2 % bacterial meningitis was revealed by Gram staining and culture methods whereas latex agglutination method detected 5.6 %. Gram-negative organisms contributed the majority of the cases (72.2 %) with Haemophilus influenzae as the leading pathogen for meningitis. Overall, 33.3 % mortality rate was found.

CONCLUSIONS

In conclusion, a significant rate of bacterial meningitis was found in this study prompting concern for national wide surveillance.

Review article: spontaneous bacterial peritonitis--bacteriology, diagnosis, treatment, risk factors and prevention

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with cirrhosis and ascites.

AIM

To review the known and changing bacteriology, risk factors, ascitic fluid interpretation, steps in performing paracentesis, treatment, prophylaxis and evolving perspectives related to SBP.

METHODS

Information was obtained from reviewing medical literature accessible on PubMed Central. The search term 'spontaneous bacterial peritonitis' was cross-referenced with 'bacteria', 'risk factors', 'ascites', 'paracentesis', 'ascitic fluid analysis', 'diagnosis', 'treatment', 'antibiotics', 'prophylaxis', 'liver transplantation' and 'nutrition'.

RESULTS

Gram-positive cocci (GPC) such as Staphylococcus, Enterococcus as well as multi-resistant bacteria have become common pathogens and have changed the conventional approach to treatment of SBP. Health care-associated and nosocomial SBP infections should prompt greater vigilance and consideration for alternative antibiotic coverage. Acid suppressive and beta-adrenergic antagonist therapies are strongly associated with SBP in at-risk individuals.

CONCLUSIONS

Third-generation, broad-spectrum cephalosporins remain a good initial choice for SBP treatment. Levofloxacin is an acceptable alternative for patients not receiving long-term flouroquinolone prophylaxis or for those with a penicillin allergy. For uncomplicated SBP, early oral switch therapy is reasonable. Alternative antibiotics such as pipercillin-tazobactam should be considered for patients with nosocomial SBP or for patients who fail to improve on traditional antibiotic regimens. Selective albumin supplementation remains an important adjunct in SBP treatment. Withholding acid suppressive medication deserves strong consideration, and discontinuing beta-adrenergic antagonist therapy in patients with end-stage liver disease and resistant ascites is standard care. Liver transplant evaluation should be undertaken for patients who develop SBP barring contraindications.

Diagnosis of spontaneous bacterial peritonitis and an in situ hybridization approach to detect an "unidentified" pathogen

Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication in cirrhotic patients with ascites. Although identifying the pathogen(s) plays a major role in the management of infectious diseases, ascitic fluid cultures often show negative results in patients with clinical signs and symptoms of SBP, and ascitic fluid cell analyses are the gold standard method for diagnosing SBP. SBP is generally diagnosed based on an increased number of polymorphonuclear neutrophils in the ascitic fluid (>250/mm(3)), and the identification of the causal pathogen may not be given consideration. We newly developed an in situ hybridization (ISH) method to provide early and direct evidence of bacterial infection in ascites in patients with SBP. This paper will review the diagnosis of SBP, including our novel approach with ISH method to detect bacterial DNA in SBP ascitic fluid.

Diagnosis of spontaneous bacterial peritonitis and an in situ hybridization approach to detect an "unidentified" pathogen

Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication in cirrhotic patients with ascites. Although identifying the pathogen(s) plays a major role in the management of infectious diseases, ascitic fluid cultures often show negative results in patients with clinical signs and symptoms of SBP, and ascitic fluid cell analyses are the gold standard method for diagnosing SBP. SBP is generally diagnosed based on an increased number of polymorphonuclear neutrophils in the ascitic fluid (>250/mm(3)), and the identification of the causal pathogen may not be given consideration. We newly developed an in situ hybridization (ISH) method to provide early and direct evidence of bacterial infection in ascites in patients with SBP. This paper will review the diagnosis of SBP, including our novel approach with ISH method to detect bacterial DNA in SBP ascitic fluid.

Measurement of calprotectin in ascitic fluid to identify elevated polymorphonuclear cell count

AIM: To evaluate the diagnostic capability of calprotectin in ascitic fluid for detecting a polymorphonuclear (PMN) cell count > 250/μL ascites.

METHODS: In this prospective observational study, a total of 130 ascites samples were analysed from 71 consecutive patients referred for paracentesis. Total and differential leukocyte cell counts were determined manually with a Neubauer chamber and gentian-violet stain. Calprotectin was measured in 1 mL ascetic fluid by enzyme-linked immunosorbent assay (ELISA) and a point-of-care (POC) lateral flow assay with the Quantum Blue^® Reader (Bühlmann Laboratories). All measurements were carried out in a central laboratory by senior personnel blinded to patient history. A PMN count > 250/μL was the primary endpoint of the study. The diagnostic value of ascitic calprotectin measurement was assessed by comparing to the final diagnosis of each patient that had been adjudicated by investigators blinded to calprotectin values.

RESULTS: The PMN count was > 250/μL in 19 samples (14.6%) from 15 patients (21.1%) and varied widely among the study population (range 10-19 800/mL and 1-17 820/mL, respectively). Spontaneous bacterial peritonitis (SBP) was the final diagnosis in four patients (5.6%). All patients with PMN ≤ 250/μL had negative bacterial culture. PMN count was elevated in five patients with peritoneal carcinomatosis, three with lymphoma, one with neuroendocrine carcinoma, and two with secondary peritonitis due to abdominal perforation. PMN cell counts correlated with ascitic calprotectin values (Spearman’s rho; r = 0.457 for ELISA, r = 0.473 for POC). A considerable range of ascitic calprotectin concentrations was detected by ELISA [median 0.43 μg/mL, interquartile range (IQR) 0.23-1.23 (range 0.10-14.93)] and POC [median 0.38 μg/mL, IQR 0.38-0.56 (range 0.38-13.31)]. Ascitic calprotectin levels were higher in samples with PMN > 250/μL, by both ELISA [median (IQR) 2.48 μg/mL (1.61-3.65) vs 0.10 μg/mL (0.10-0.36), P < 0.001] and POC [2.78 μg/mL (2.05-5.37) vs 0.38 μg/mL (0.38-0.41), P < 0.001]. The area under the receiver operating characteristics curve for identifying an elevated PMN count was 0.977 (95%CI: 0.933 to 0.995) for ELISA and 0.982 (95%CI: 0.942 to 0.997) for POC (P = 0.246 vs ELISA). Using the optimal cut-off value for ELISA (0.63 μg/mL), ascitic calprotectin had 94.8% sensitivity, 89.2% specificity, positive and negative likelihood ratios of 8.76 and 0.06 respectively, positive and negative predictive values of 60.0% and 99.0% respectively, and 90.0% overall accuracy. Using the optimal cut-off value for POC (0.51 μg/mL), the respective values were 100.0%, 84.7%, 6.53, 0.00, 52.8%, 100% and 87.7%. Correlation between ELISA and POC was excellent (r = 0.873, P < 0.001). The mean ± SD of the difference was -0.11 ± 0.48 μg/mL with limits of agreement of + 0.8 μg/mL (95%CI: 0.69 to 0.98) and -1.1 μg/mL (95%CI: -1.19 to -0.91).

CONCLUSION: Ascitic calprotectin reliably predicts PMN count > 250/μL, which may prove useful in the diagnosis of SBP, especially with a readily available bedside testing device.

Spontaneous bacterial peritonitis: How to deal with this life-threatening cirrhosis complication?

Spontaneous bacterial peritonitis (SBP) is one of the most common and life-threatening complications of cirrhosis. It occurs in 10% to 30% of patients admitted to hospital and recent studies tend to demonstrate that SBP incidence seems to be decreasing in its frequency. A bacterial overgrowth with translocation through the increased permeable small intestinal wall and impaired defense mechanisms is considered to be the main mechanism associated with its occurrence. The Gram-negative aerobic bacteria are the major responsible for SBP episodes and Gram-positive bacteria, mainly Staphylococcus aureus, are being considered an emergent agent causing SBP. The prompt diagnosis of SBP is the key factor for reduction observed in mortality rates in recent years. The clinical diagnosis of SBP is neither sensitive nor specific and the search for new practical and available tools for a rapid diagnosis of SBP is an important endpoint of current studies. Reagent strips were considered a promising and faster way of SBP diagnosis. The prompt use of empirical antibiotics, mostly cefotaxime, improves significantly the short-term prognosis of cirrhotic patients with SBP. The recurrence rate of SBP is high and antibiotic prophylaxis has been recommended in high-risk settings. Unfortunately, the long-term prognosis remains poor.

A new highly sensitive point of care screen for spontaneous bacterial peritonitis using the leukocyte esterase method

BACKGROUND & AIMS

Urine reagent strips measuring leukocyte esterase activity have been studied to screen spontaneous bacterial peritonitis (SBP) but are insensitive. We calibrated a strip specifically for ascitic fluid to achieve high sensitivity in this diagnosis.

METHODS

Experiments were conducted on ascitic fluid from patients with cirrhosis. Samples with SBP were diluted with native acellular ascitic fluid to achieve PMN counts below, above, and close to the diagnostic threshold of 250 PMN/microl. A model of SBP was created by spiking negative ascitic fluid samples (<250 PMN/microl) with activated PMN from blood of patients with sepsis, and diluted to achieve a range of PMN. Aliquots were tested at 2, 3, 4, and 10 min with the Periscreen leukocyte esterase strip. PMN/microl was correlated to timings and color scales: white defined negative (PMN <250/microl); and shades of brown, purple, and pink defined positive. Ascitic fluid samples were obtained from 58 patients. Negative ascitic fluid was used from 32 to generate the model SBP.

RESULTS

One thousand three hundred and four experiments were performed with a median PMN count of 492/microl (0-7510). After exclusion of uninterpretable colorimetric results, 1089 experiments were analyzed [PMN of 444/microl (0-7510)]. The best result was obtained at 3 min (n=299), with Se: 100%, Sp: 57.9%; NPV: 100%, PPV: 76.5%. The test was not interpretable in bloody, chylous or bilious ascitic fluid, or concurrent imipenem treatment.

CONCLUSIONS

This new leukocyte esterase strip calibrated to an ascitic fluid PMN count 250/microl is a robust screening tool when the strip turns any hue of tan/brown at 3 min.

A comparison of diagnostic efficacies among different reagent strips and automated cell count in spontaneous bacterial peritonitis

BACKGROUND

Currently, decision to give antibiotics in spontaneous bacterial peritonitis (SBP) suspected patient depends mainly on the result of manual cell count, which requires significant waiting period. Recently, many reports on the efficacies of reagent strips and a few reports of automated cell count are available but there has been no direct comparison study.

AIMS

This prospective study was to assess the diagnostic efficacies of different reagent strips (Aution, Multistix, Combur) and automated cell count.

METHODS AND RESULTS

A total of 250 paracenteses were performed. There were 40 specimens obtained from patients with clinical suspicion for SBP, the rest were obtained from non SBP suspected patients. Thirty specimens from 250 samples (12%) were diagnosed as SBP by manual cell count. Automated system provided higher value for SBP diagnosis in all parameters (sensitivity, specificity, PPV, NPV, and accuracy; 87.5-99.1%) whereas the strip tests provided lower number in all parameters (80-98.6%). Multistix provided the lowest sensitivity (80%). The false negative rates by Aution, Multistix, Combur tests and automated cell count were 10%, 20%, 10% and 3.3%, respectively. By lowering the cut off for SBP diagnosis with the automated system to 200 cells/mm(3), there was no false negative.

CONCLUSIONS

Comparing to reagent strips, automated cell count is a better screening tool for SBP diagnosis because it provides higher validity scores and a lower false negative rate. However, the discrepancy of cell count reading may occur, we suggest using a lower cut off for SBP diagnosis by the automated system.

Comments on the editorial by Riggio & Ageloni on the ascitic fluid analysis

Angeloni et al published a landmark study on the use of Coulter counters in spontaneous bacterial peritonitis (SBP) diagnosis. Riggio and Angeloni have recently published an editorial on the ascitic fluid analysis in diagnosis and monitoring of SBP. Herein, some points of interest are discussed.

Ascitic fluid analysis for diagnosis and monitoring of spontaneous bacterial peritonitis

Polymorphonuclear (PMN) cell count in the ascitic fluid is essential for the diagnosis and management of spontaneous bacterial peritonitis (SBP). To date, PMN cell count is routinely performed by traditional manual counting. However, this method is time-consuming, costly, and not always timely available. Therefore, considerable efforts have been made in recent years to develop an alternative test for a more rapid diagnosis and monitoring of SBP. The use of urinary reagent strips was proposed to achieve an “instant” bedside diagnosis of SBP. A series of reports evaluated the urine strip test for SBP diagnosis and reported promising results. However, a recent large multicenter study revealed a surprising lack of diagnostic efficacy of the urine screening test for SBP diagnosis. Another method, more recently proposed as an alternative to the manual PMN count, is the measurement of lactoferrin in ascitic fluid, but the data available on the diagnostic value of this test are limited to a single study. However, both urinary reagent strips and ascitic lactoferrin tests are qualitative methods and need, therefore, to be further confirmed by standard cytology of the ascitic fluid. To date, the only quantitative method proposed as a valid alternative to manual PMN counting is automated blood cell counters, commonly used in all laboratories for blood cell counting. Data available in the literature on the diagnostic performance of this method are limited but very promising, and this tool seems to have the potential to replace the manual counting method.

Spontaneous bacterial peritonitis

Since its initial description in 1964, research has transformed spontaneous bacterial peritonitis (SBP) from a feared disease (with reported mortality of 90%) to a treatable complication of decompensated cirrhosis, albeit with steady prevalence and a high recurrence rate. Bacterial translocation, the key mechanism in the pathogenesis of SBP, is only possible because of the concurrent failure of defensive mechanisms in cirrhosis. Variants of SBP should be treated. Leucocyte esterase reagent strips have managed to shorten the ‘tap-to-shot’ time, while future studies should look into their combined use with ascitic fluid pH. Third generation cephalosporins are the antibiotic of choice because they have a number of advantages. Renal dysfunction has been shown to be an independent predictor of mortality in patients with SBP. Albumin is felt to reduce the risk of renal impairment by improving effective intravascular volume, and by helping to bind pro-inflammatory molecules. Following a single episode of SBP, patients should have long-term antibiotic prophylaxis and be considered for liver transplantation.

Leucocyte esterase reagent strips for the diagnosis of spontaneous bacterial peritonitis: a systematic review

The reported incidence of spontaneous bacterial peritonitis (SBP) is 7-30% per annum in cirrhotic patients. Timely diagnosis and treatment is crucial to reduce mortality owing to this infection. Recently, leucocyte esterase reagent strips have been tested in the diagnosis of infection in the ascitic fluid. The objective was to evaluate the diagnostic value of leucocyte esterase reagent strips in SBP in cirrhotic patients with ascites, by systematically reviewing the evidence from prospective clinical studies. We performed a comprehensive literature search in Medline up to July 2007 for adult human prospective clinical studies. Two reviewers independently checked all identified studies for fulfillment of predefined inclusion criteria, extracted data and assessed methodological quality of included studies. We had decided a priori to pool the studies via meta-analysis, only if statistical heterogeneity was found to be nonsignificant (P>0.10). Seventeen studies were included. Statistical heterogeneity among studies was found to be highly significant (P<0.001) in all analyses, precluding pooling of data for meta-analysis. Compared with the manual polymorphonuclear count ('gold standard'), leucocyte esterase reagent strips were found to have sensitivity ranging from 45 to 100%, specificity ranging from 81 to 100%, positive predictive value ranging from 42 to 100% and negative predictive value ranging from 87 to 100%. Despite the wide variation in sensitivity and positive predictive value between studies, the consistently high negative predictive value of leucocyte esterase reagent strips in SBP diagnosis should gain it a place in the ascitic tap diagnostic algorithm.

Accuracy of the automated cell counters for management of spontaneous bacterial peritonitis

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 ± 58 cells/mm³, 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 effective in 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.

Efficacy of current guidelines for the treatment of spontaneous bacterial peritonitis in the clinical practice

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 (PMN) cell count was > 250 cells/mm³, and empirically treated with cefotaxime.

RESULTS: Thirty-eight SBP episodes occurred in 32 cirrhotics (22 men/10 women; mean age: 58.6 ± 11.2 years). Prevalence of SBP, in our population, was 17%. 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 and evaluating 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.

[Bacterial infections in liver cirrhosis]

Bacterial infections are well described complications of cirrhosis that greatly increase mortality rates. Two factors play important roles in the development of bacterial infections in these patients: the severity of liver disease and gastrointestinal haemorrhage. The most common infections are spontaneous bacterial peritonitis, urinary tract infections, pneumonia and sepsis. Gram-negative and gram-positive bacteria are equal causative organisms. For primary prophylaxis, short-term antibiotic treatment (oral norfloxacin or ciprofloxacin) is indicated in cirrhotic patients (with or without ascites) admitted with gastrointestinal haemorrhage (variceal or non-variceal). Administration of norfloxacin is advisable for hospitalized patients with low ascitic protein even without gastrointestinal haemorrhage. The first choice in empirical treatment of spontaneous bacterial peritonitis is the iv. III. generation cephalosporin; which can be switched for a targeted antibiotic regime based on the result of the culture. The duration of therapy is 5-8 days. Amoxicillin/clavulanic acid and fluoroquinolones--patients not on prior quinolone prophylaxis--were shown to be as effective and safe as cefotaxime. In patients with evidence of improvement, iv. antibiotics can be switched safely to oral antibiotics after 2 days. In case of renal dysfunction, iv albumin should also be administered. Long-term antibiotic prophylaxis is recommended in patients who have recovered from an episode of spontaneous bacterial peritonitis (secondary prevention). For "selective intestinal decontamination", poorly absorbed oral norfloxacin is the preferred schedule. Oral ciprofloxacin or levofloxacin (added gram positive spectrum) all the more are reasonable alternatives. Trimethoprim/sulfamethoxazole is only for patients who are intolerant to quinolones. Prophylaxis is indefinite until disappearance of ascites, transplant or death. Long-term prophylaxis is currently not recommended for patients without previous spontaneous bacterial peritonitis episode, not even when refractory ascites or low ascites protein content is present.

Spontaneous bacterial peritonitis

Spontaneous bacterial peritonitis (SBP) is the infection of ascitic fluid in the absence of any intra-abdominal, surgically treatable source of infection. Despite timely diagnosis and treatment its reported incidence in ascitic patients varies between 7-30%. Ascitic paracentesis remains the chief diagnostic procedure. Automated cell counters have the same diagnostic accuracy as the manual measurement of white cells. Lately, the use of leucocyte reagent strips (dipsticks) has emerged as a useful alternative. Examination of the fluid is not complete unless the sample is inoculated in blood culture bottles. Treatment is currently with third-generation cephalosporins or oral quinolones. Following a single episode of SBP patients should have long term antibiotic prophylaxis.

Total ascitic fluid leukocyte count for reliable exclusion of spontaneous bacterial peritonitis in patients with ascites

BACKGROUND AND AIMS

The diagnosis of spontaneous bacterial peritonitis (SBP) in patients with ascites is established by definition with a polymorphonuclear (PMN) cell count in the ascitic fluid greater than 0.250 g/l determined via cytological (microscopic) examination. In this study, we correlated the automatically assessed total ascitic nucleated cell count with PMN and determined its predictive value for diagnosis of SBP.

METHODS

Six hundred and eleven consecutive paracenteses of 179 patients with ascites of various aetiologies (liver cirrhosis, hepatocellular carcinoma, peritoneal carcinomatosis, and ascites of other aetiology) were studied retrospectively.

RESULTS

The most reliable diagnostic cut-off level was determined for differentiation between SBP and non-SBP via receiver operating characteristics analysis. A total ascitic nucleated cell count less than 1.0 g/l is unlikely to represent SBP (negative predictive value, 95.5%).

CONCLUSIONS

If ascitic fluid samples with machine-made total ascitic nucleated cell count below 1.0 g/l are not followed by additional laboratory tests, the risk of missing the diagnosis of SBP is low. Applying these criteria we would have classified 51 samples of 611 samples (20 of 179 patients) wrongly using the cut-off value of 1 g/l. On the other hand we would have spared cytologic evaluation in about 63% of paracentesis performed in our hospital. Nevertheless, to insure patient safety, standard laboratory analysis is recommended in circumstances of clinical uncertainty. Thus, patients with first manifestation of ascites should always receive cytologic examination and full diagnostic investigation to exclude other causes of ascites.

Use of reagent strips for the rapid diagnosis of spontaneous bacterial empyema

GOALS

To assess the utility of reagent strips for rapid diagnosis of spontaneous bacterial empyema in cirrhotic patients with hepatic hydrothorax.

BACKGROUND

Analysis of ascitic fluid using reagent strips is a useful diagnostic test for spontaneous bacterial peritonitis.

METHODS

A reagent strip for leukocyte esterase designed for the testing of urine was used to evaluate pleural fluid analysis in 47 nonselected thoracenteses in 28 cirrhotic patients with hepatic hydrothorax.

RESULTS

Twelve spontaneous bacterial empyemas were diagnosed. Simultaneous spontaneous bacterial peritonitis was present in 7 of 10 cases in which ascites fluid was analyzed. When a test result of 3 or 4 was considered positive, sensitivity was 83% (10 of 12), specificity was 100% (35 of 35), and positive predictive value was 100%. When result of 2 or more was considered positive, sensitivity was 92% (11 of 12), specificity was 80% (28 of 35), and negative predictive value was 97%.

CONCLUSION

Analysis of pleural fluid with reagent strips is a rapid, easy to use, and inexpensive tool for the diagnosis of spontaneous bacterial empyema in cirrhotic patients. A positive result should be considered an indication for antibiotic therapy.

Rapid diagnosis of spontaneous bacterial peritonitis with leukocyte esterase reagent strips in a European and in an American center

BACKGROUND

Timely diagnosis and treatment of spontaneous bacterial peritonitis (SBP) are essential to survival. The purpose of the present paper was to evaluate leukocyte esterase reagent strips (Nephur-Test and MultistixSG10) in the bedside diagnosis of SBP.

METHODS

Patients with cirrhotic ascites were prospectively included in France (center 1) and in the USA (center 2). Paracenteses were performed on admission and repeated as indicated. Bedside reagent strip testing was performed on the ascitic fluid and compared to manual cell count with differential and ascitic fluid culture. In center 1, the Nephur-Test was tested in all cases, with dual testing with MultistixSG10 in a subgroup. In center 2, all cases had dual testing. Spontaneous bacterial peritonitis was defined as a polymorphonuclear ascites count > or =250/microL.

RESULTS

A total of 184 samples was obtained in 76 patients. Center 1 included 151 samples from 53 patients. Seven samples had SBP, obtained in six patients. Center 2 included 33 samples from 23 patients. Six samples had SBP, obtained in five patients. The sensitivity, specificity, positive and negative predictive value of the reagent strips were as follows. Center 1/Nephur-Test: 86%, 100%, 100%, 99%; center 1/MultistixSG10: 100%, 100%, 100%, 100%; center 2/Nephur-Test: 100%, 92.5%, 75%, 100%; center 2/MultistixSG10: 83%, 96%, 83%, 96%.

CONCLUSION

Leukocyte esterase reagent strips may provide a rapid bedside diagnosis of SBP.

Portal hypertension

PURPOSE OF REVIEW

This review discusses the advances in the pathophysiology, diagnosis, and management of the complications of portal hypertension that have occurred in the past year.

RECENT FINDINGS

The specific topics reviewed are the pathophysiology of portal hypertension (including recent findings regarding intrahepatic vascular resistance and splanchnic vasodilatation) and experimental methods used to act on the mechanisms that lead to portal hypertension, as well as recent advances in the diagnosis and management of the complications of portal hypertension.

SUMMARY

The specific complications discussed in this review are varices and variceal bleeding (primary prophylaxis, treatment of the acute episode, and secondary prophylaxis), portal hypertensive gastropathy, ascites, hepatorenal syndrome, spontaneous bacterial peritonitis, the cardiopulmonary complications of portal hypertension (hepatopulmonary syndrome, portopulmonary hypertension, cardiac dysfunction), and hepatic encephalopathy.

Ascites and intraabdominal infection

PURPOSE OF REVIEW

This review will give an overview of current trends in diagnosis, treatment, and pathogenesis of ascites and intraabdominal infection in cirrhotic and noncirrhotic critically ill patients.

RECENT FINDINGS

Single clone-bacterial DNA has been found in sterile ascites and serum, proving the concept of direct translocation. Activation of mesenteric macrophages can be induced by splanchnic vasodilatation but also by hypoxia. Carbon monoxide, an end product of heme catabolism, promotes splanchnic vasodilatation, representing a possible link between gastrointestinal hemorrhage and circulatory dysfunction. Colorimetric test strips and automated counters accurately diagnose spontaneous bacterial peritonitis. Vasopressin V2-antagonists have been introduced as novel therapy for impaired water excretion in hyponatremia.

SUMMARY

Emerging pathophysiological concepts have modified the conventional view of hydrostatic and Starling forces in the evolution of ascites. Current data indicate that the dynamic sequence of bacterial translocation, mesenteric inflammation, splanchnic vasodilatation and intrahepatic vasoconstriction determines occurrence, severity, and outcome of ascites and intraabdominal infection.