Spontaneous bacterial peritonitis: from pathophysiology to prevention

Systematically analysis of decompensated cirrhotic patients with spontaneous bacterial peritonitis to identify diagnostic and prognostic indexes

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a common complication in patients with cirrhosis. The diagnosis of SBP is still mostly based on ascites cultures and absolute ascites polymorphonuclear (PMN) cell count, which restricts the widely application in clinical settings. This study aimed to identify reliable and easy-to-use biomarkers for both diagnosis and prognosis of cirrhotic patients with SBP.

METHODS

We conducted a retrospective study including 413 cirrhotic patients from March 2013 to July 2022 in the First Affiliated Hospital of Guangxi Medical University. Patients' clinical characteristics and laboratory indices were collected and analyzed. Two machine learning methods (Xgboost and LASSO algorithms) and a logistic regression analysis were adopted to screen and validate the indices associated with the risk of SBP. A predictive model was constructed and validated using the estimated area under curve (AUC). The indices related to the survival of cirrhotic patients were also analyzed.

RESULTS

A total of 413 cirrhotic patients were enrolled in the study, of whom 329 were decompensated and 84 were compensated. 52 patients complicated and patients with SBP had a poorer Child-Pugh score (P < 0.05). Patients with SBP had a greater proportion of malignancies than those without SBP(P < 0.05). The majority of laboratory test indicators differed significantly between patients with and without SBP (P < 0.05). Albumin, neutrophil-to-lymphocyte ratio (NLR), and ferritin-to-neutrophil ratio (FNR) were found to be independently associated with SBP in decompensated cirrhotic patients using LASSO algorithms, and logistic regression analysis. The model established by the three indices showed a high predictive value with an AUC of 0.808. Furthermore, increased neutrophils, ALP, and C-reactive protein-to-albumin ratio (CAR) were associated with the shorter survival time of patients with decompensated cirrhosis, and the combination of these indices showed a greater predictive value for cirrhotic patients.

CONCLUSIONS

The present study identified FNR as a novel index in the diagnosis of SBP in decompensated patients with cirrhosis. A model based on neutrophils, ALP and CAR showed high performance in predicting the prognosis of patients with decompensated cirrhosis.

The Usefulness of Mayo End-stage Liver Disease (MELD) and MELD-Sodium (MELD-Na) Scores for Predicting Mortality in Cirrhotic Patients With Spontaneous Bacterial Peritonitis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a common infection in patients with cirrhosis and ascites. Currently, the accuracy of the model for end-stage liver disease (MELD) and MELD-sodium (MELD-Na) as prognostic scores in this cohort is unclear. This study aimed to evaluate and compare the accuracy of MELD and MELD-Na for predicting 90-day mortality and determine whether the mortality risk estimates they provide accurately reflect the poor prognosis of patients with SBP Methods: Patients with cirrhosis and SBP were retrospectively identified from ascitic fluid samples sent for microscopy, culture and sensitivity analysis (1/1/18-31/12/20) and a previous audit. MELD and MELD-Na scores at diagnosis were calculated and associations with 90-day mortality were assessed using univariate analysis. Receiver operator characteristic curves were compared, and standardised mortality ratios (SMRs) were calculated by comparing the number of deaths observed to the number predicted by MELD and MELD-Na.

RESULTS

Of the 567 patients identified, 15 patients with cirrhosis and SBP were included. The 90-day mortality rate was 66.7% (10/15). Only concurrent hyponatremia (<135mmol/L) was associated with mortality (6/10 non-survivors vs 0/5 survivors, p=0.04). The difference in MELD and MELD-Na's C-statistic was not significant: 0.66 (95% Cl:0.35-0.98) vs 0.74 (95% Cl:0.47-1.0) respectively (p=0.72). Patients with a MELD-Na >18.5 had significantly higher 90-day mortality than patients with MELD-Na ≤18.5 (88.9% (8/9) vs. 33.3% (2/6), p=0.05). The SMR (95% Cl) for each MELD decile evaluated was 33.3 (0-79.5), 11.1 (0.2-22.0) and 3.4 (0-7.0) for scores ≤9,10-19 and 20-29 respectively. For each MELD-Na tertile, these were: 25 (0-59.6), 5.2 (0.1-10.3) and 2.7 (0.1-8.1) for scores <17,17-26, ≥27 respectively.

CONCLUSION

In a small cohort of patients with cirrhosis and SBP, the MELD's accuracy in predicting 90-day mortality was limited. MELD-Na's accuracy was higher but not significantly. Both scores consistently underestimated participants' mortality, therefore future studies could evaluate the accuracy of alternative prognostic scores in this patient group.

Fluoroquinolone-resistant strains in cirrhotic patients with spontaneous bacterial peritonitis: microbiological and molecular aspects

OBJECTIVES

This study aimed to determine the causative bacterial agents of spontaneous bacterial peritonitis (SBP) in patients with cirrhosis and to define antibiotic-resistance patterns in addition to identifying the genetic mutations in the quinolone resistance determining regions (QRDRs).

PATIENTS AND METHODS

Twenty milliliters of ascetic fluid was obtained from 51 patients with SBP. The antibiotic-sensitivity patterns of different strains were determined by the Kirby-Bauer method. Extracted bacterial DNA was used to determine the mutations in four different genes in QRDRs (gyrA, gyrB, parC, and parE) by sequencing after gene amplification by PCR.

RESULTS

Gram-negative bacilli were detected in 60.7% of the patients. Escherichia coli was detected in 33.3% of the patients, and Staphylococcus aureus was detected in 21.6%. Gram-negative bacilli showed the best sensitivity to meropenem (90.3%), followed by amikacin (83.9%). Gram-positive cocci were sensitive to vancomycin and oxacillin at 90 and 80%, respectively. Fluoroquinolone resistance was detected in 27% of the bacterial strains. Mutations in the gyrA and parC genes were detected in quinolone-resistant strains (64.3 and 35.7%, respectively). Several mutations were found in the gyrA gene (Ser83Leu, Ser81Phe, and Ser-84Leu). Ser80Ile and Ser79Tyr mutations were detected in the parC gene. No mutation was detected in the parE gene.

CONCLUSION

Frequent use of antibiotics as prophylaxis against SBP leads to an increase in antibiotic resistance and changes the microbial pattern of causative agents. The gyrA gene mutation was the most common mutation detected in fluoroquinolone-resistant strains.

An Epidemiological Meta-Analysis on the Worldwide Prevalence, Resistance, and Outcomes of Spontaneous Bacterial Peritonitis in Cirrhosis

Background and Aims: Spontaneous bacterial peritonitis (SBP) is a common and potentially fatal complication of liver cirrhosis. This study aims to analyze the prevalence of SBP among liver cirrhotic patients according to geographical location and income level, and risk factors and outcomes of SBP. Methods: A systematic search for articles describing prevalence, risk factors and outcomes of SBP was conducted. A single-arm meta-analysis was performed using generalized linear mix model (GLMM) with Clopper-Pearson intervals. Results: Ninety-Nine articles, comprising a total of 5,861,142 individuals with cirrhosis were included. Pooled prevalence of SBP was found to be 17.12% globally (CI: 13.63-21.30%), highest in Africa (68.20%; CI: 12.17-97.08%), and lowest in North America (10.81%; CI: 5.32-20.73%). Prevalence of community-acquired SBP was 6.05% (CI: 4.32-8.40%), and 11.11% (CI: 5.84-20.11%,) for healthcare-associated SBP. Antibiotic-resistant microorganisms were found in 11.77% (CI: 7.63-17.73%) of SBP patients. Of which, methicillin-resistant Staphylococcus aureus was most common (6.23%; CI: 3.83-9.97%), followed by extended-spectrum beta-lactamase producing organisms (6.19%; CI: 3.32-11.26%), and lastly vancomycin-resistant enterococci (1.91%; CI: 0.41-8.46%). Subgroup analysis comparing prevalence, antibiotic resistance, and outcomes between income groups was conducted to explore a link between socioeconomic status and SBP, which revealed decreased risk of SBP and negative outcomes in high-income countries. Conclusion: SBP remains a frequent complication of liver cirrhosis worldwide. The drawn link between income level and SBP in liver cirrhosis may enable further insight on actions necessary to tackle the disease on a global scale.

Multivariate predictive model for asymptomatic spontaneous bacterial peritonitis in patients with liver cirrhosis

BACKGROUND

Spontaneous bacterial peritonitis (SBP) is a detrimental infection of the ascitic fluid in liver cirrhosis patients, with high mortality and morbidity. Early diagnosis and timely antibiotic administration have successfully decreased the mortality rate to 20%-25%. However, many patients cannot be diagnosed in the early stages due to the absence of classical SBP symptoms. Early diagnosis of asymptomatic SBP remains a great challenge in the clinic.

AIM

To establish a multivariate predictive model for early diagnosis of asymptomatic SBP using positive microbial cultures from liver cirrhosis patients with ascites.

METHODS

A total of 98 asymptomatic SBP patients and 98 ascites liver cirrhosis patients with negative microbial cultures were included in the case and control groups, respectively. Multiple linear stepwise regression analysis was performed to identify potential indicators for asymptomatic SBP diagnosis. The diagnostic performance of the model was estimated using the receiver operating characteristic curve.

RESULTS

Patients in the case group were more likely to have advanced disease stages, cirrhosis related-complications, worsened hematology and ascites, and higher mortality. Based on multivariate analysis, the predictive model was as follows: y (P) = 0.018 + 0.312 × MELD (model of end-stage liver disease) + 0.263 × PMN (ascites polymorphonuclear) + 0.184 × N (blood neutrophil percentage) + 0.233 × HCC (hepatocellular carcinoma) + 0.189 × renal dysfunction. The area under the curve value of the established model was 0.872, revealing its high diagnostic potential. The diagnostic sensitivity was 73.5% (72/98), the specificity was 86.7% (85/98), and the diagnostic efficacy was 80.1%.

CONCLUSION

Our predictive model is based on the MELD score, polymorphonuclear cells, blood N, hepatocellular carcinoma, and renal dysfunction. This model may improve the early diagnosis of asymptomatic SBP.

Ascitic calprotectin as a useful marker in the diagnosis of spontaneous bacterial peritonitis in adults

Background

Ascitic fluid polymorphonuclear leucocyte count (PMN) is known to be the gold standard for spontaneous bacterial peritonitis (SBP) diagnosis. The aim of this work was to assess ascitic calprotectin for SBP diagnosis. Serum C-reactive protein (CRP), high sensitivity C-reactive protein (hsCRP), nitrous oxide, ascitic PMN, ascitic leucocyte esterase and ascitic calprotectin were measured.

Results

The average age of our patients was 55.25 ± 7.89 years, mostly males (n = 51, 63.8%), anti-HCV antibodies were positive in (n = 61, 76.3%). Sixty-four patients (80%) were Child-Pugh C and their average MELD was 24.29 ± 8.06. Patients with SBP had statistically significant higher median MELD score (26.5 vs. 19) and higher average Child-Pugh score (12.18 ± 1.74 vs. 10.5 ± 1.97). Forty patients had SBP and 40 patients were without SBP. Both the serum and ascitic nitrous oxide did not differ statistically between patients with and without SBP. In contrast, patients with SBP had higher median serum CRP (49 vs. 12 mg/dL), hsCRP (58,000 vs. 23,750 ng/dL) and ascitic calprotectin (7.57 vs. 1.1 ng/mL). The ascitic leucocyte esterase test was positive in 95% of SBP patients in contrast to 2.5% patients without SBP. Ascitic calprotectin >2 ng/mL had 90% sensitivity, 92.5% specificity, 92.3% positive predictive value and 90.2% negative predictive value. MELD, CRP, hsCRP and ascitic calprotectin are independent predictors of SBP.

Conclusion

Ascitic calprotectin is a useful marker for SBP diagnosis.

Antibiotic prophylaxis to prevent spontaneous bacterial peritonitis in people with liver cirrhosis: a network meta-analysis

BACKGROUND

Approximately 2.5% of all hospitalisations in people with liver cirrhosis are for spontaneous bacterial peritonitis. Spontaneous bacterial peritonitis is associated with significant short-term mortality; therefore, it is important to prevent spontaneous bacterial peritonitis in people at high risk of developing it. Antibiotic prophylaxis forms the mainstay preventive method, but this has to be balanced against the development of drug-resistant spontaneous bacterial peritonitis, which is difficult to treat, and other adverse events. Several different prophylactic antibiotic treatments are available; however, there is uncertainty surrounding their relative efficacy and optimal combination.

OBJECTIVES

To compare the benefits and harms of different prophylactic antibiotic treatments for prevention of spontaneous bacterial peritonitis in people with liver cirrhosis using a network meta-analysis and to generate rankings of the different prophylactic antibiotic treatments according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers to November 2018 to identify randomised clinical trials in people with cirrhosis at risk of developing spontaneous bacterial peritonitis.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or status) in adults with cirrhosis undergoing prophylactic treatment to prevent spontaneous bacterial peritonitis. We excluded randomised clinical trials in which participants had previously undergone liver transplantation, or were receiving antibiotics for treatment of spontaneous bacterial peritonitis or other purposes.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio, rate ratio, and hazard ratio (HR) with 95% credible intervals (CrI) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included 29 randomised clinical trials (3896 participants; nine antibiotic regimens (ciprofloxacin, neomycin, norfloxacin, norfloxacin plus neomycin, norfloxacin plus rifaximin, rifaximin, rufloxacin, sparfloxacin, sulfamethoxazole plus trimethoprim), and 'no active intervention' in the review. Twenty-three trials (2587 participants) were included in one or more outcomes in the review. The trials that provided the information included people with cirrhosis due to varied aetiologies, with or without other features of decompensation, having ascites with low protein or previous history of spontaneous bacterial peritonitis. The follow-up in the trials ranged from 1 to 12 months. Many of the trials were at high risk of bias, and the overall certainty of evidence was low or very low. Overall, approximately 10% of trial participants developed spontaneous bacterial peritonitis and 15% of trial participants died. There was no evidence of differences between any of the antibiotics and no intervention in terms of mortality (very low certainty) or number of serious adverse events (very low certainty). However, because of the wide CrIs, clinically important differences in these outcomes cannot be ruled out. None of the trials reported health-related quality of life or the proportion of people with serious adverse events. There was no evidence of differences between any of the antibiotics and no intervention in terms of proportion of people with 'any adverse events' (very low certainty), liver transplantation (very low certainty), or the proportion of people who developed spontaneous bacterial peritonitis (very low certainty). The number of 'any' adverse events per participant was fewer with norfloxacin (rate ratio 0.74, 95% CrI 0.59 to 0.94; 4 trials, 546 participants; low certainty) and sulfamethoxazole plus trimethoprim (rate ratio 0.19, 95% CrI 0.02 to 0.81; 1 trial, 60 participants; low certainty) versus no active intervention. There was no evidence of differences between the other antibiotics and no intervention in the number of 'any' adverse events per participant (very low certainty). There were fewer other decompensation events with rifaximin versus no active intervention (rate ratio 0.61, 65% CrI 0.46 to 0.80; 3 trials, 575 participants; low certainty) and norfloxacin plus neomycin (rate ratio 0.06, 95% CrI 0.00 to 0.33; 1 trial, 22 participants; low certainty). There was no evidence of differences between the other antibiotics and no intervention in the number of decompensations events per participant (very low certainty). None of the trials reported health-related quality of life or development of symptomatic spontaneous bacterial peritonitis. One would expect some correlation between the above outcomes, with interventions demonstrating effectiveness across several outcomes. This was not the case. The possible reasons for this include sparse data and selective reporting bias, which makes the results unreliable. Therefore, one cannot draw any conclusions from these inconsistent differences based on sparse data. There was no evidence of any differences in the subgroup analyses (performed when possible) based on whether the prophylaxis was primary or secondary.

FUNDING

the source of funding for five trials were organisations who would benefit from the results of the study; six trials received no additional funding or were funded by neutral organisations; and the source of funding for the remaining 18 trials was unclear.

AUTHORS' CONCLUSIONS

Based on very low-certainty evidence, there is considerable uncertainty about whether antibiotic prophylaxis is beneficial, and if beneficial, which antibiotic prophylaxis is most beneficial in people with cirrhosis and ascites with low protein or history of spontaneous bacterial peritonitis. Future randomised clinical trials should be adequately powered, employ blinding, avoid postrandomisation dropouts (or perform intention-to-treat analysis), and use clinically important outcomes such as mortality, health-related quality of life, and decompensation events.

Antibiotic treatment for spontaneous bacterial peritonitis in people with decompensated liver cirrhosis: a network meta-analysis

BACKGROUND

Approximately 2.5% of all hospitalisations in people with cirrhosis are for spontaneous bacterial peritonitis (SBP). Antibiotics, in addition to supportive treatment (fluid and electrolyte balance, treatment of shock), form the mainstay treatments of SBP. Various antibiotics are available for the treatment of SBP, but there is uncertainty regarding the best antibiotic for SBP.

OBJECTIVES

To compare the benefits and harms of different antibiotic treatments for spontaneous bacterial peritonitis (SBP) in people with decompensated liver cirrhosis.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until November 2018 to identify randomised clinical trials on people with cirrhosis and SBP.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in adults with cirrhosis and SBP. We excluded randomised clinical trials in which participants had previously undergone liver transplantation.

DATA COLLECTION AND ANALYSIS

Two review authors independently identified eligible trials and collected data. The outcomes for this review included mortality, serious adverse events, any adverse events, resolution of SBP, liver transplantation, and other decompensation events. We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio, rate ratio, and hazard ratio with 95% credible intervals (CrIs) based on an available-case analysis, according to the National Institute of Health and Care Excellence (NICE) Decision Support Unit guidance.

MAIN RESULTS

We included a total of 12 trials (1278 participants; 13 antibiotics) in the review. Ten trials (893 participants) were included in one or more outcomes in the review. The trials that provided the information included patients having cirrhosis with or without other features of decompensation of varied aetiologies. The follow-up in the trials ranged from one week to three months. All the trials were at high risk of bias. Only one trial was included under each comparison for most of the outcomes. Because of these reasons, there is very low certainty in all the results. The majority of the randomised clinical trials used third-generation cephalosporins, such as intravenous ceftriaxone, cefotaxime, or ciprofloxacin as one of the interventions.Overall, approximately 75% of trial participants recovered from SBP and 25% of people died within three months. There was no evidence of difference in any of the outcomes for which network meta-analysis was possible: mortality (9 trials; 653 participants), proportion of people with any adverse events (5 trials; 297 participants), resolution of SBP (as per standard definition, 9 trials; 873 participants), or other features of decompensation (6 trials; 535 participants). The effect estimates in the direct comparisons (when available) were very similar to those of network meta-analysis. For the comparisons where network meta-analysis was not possible, there was no evidence of difference in any of the outcomes (proportion of participants with serious adverse events, number of adverse events, and proportion of participants requiring liver transplantation). Due to the wide CrIs and the very low-certainty evidence for all the outcomes, significant benefits or harms of antibiotics are possible.None of the trials reported health-related quality of life, number of serious adverse events, or symptomatic recovery from SBP.

FUNDING

the source of funding for two trials were industrial organisations who would benefit from the results of the trial; the source of funding for the remaining 10 trials was unclear.

AUTHORS' CONCLUSIONS

Short-term mortality after SBP is about 25%. There is significant uncertainty about which antibiotic therapy is better in people with SBP.We need adequately powered randomised clinical trials, with adequate blinding, avoiding post-randomisation dropouts (or performing intention-to-treat analysis), and using clinically important outcomes, such as mortality, health-related quality of life, and adverse events.

Periarrest intestinal bacterial translocation and resuscitation outcome

During the periarrest period, intestinal ischemia may result in barrier dysfunction and bacterial translocation, which has clear mechanistic links to inflammation and cascade stimulation, especially in patients who are treated with therapeutic hypothermia. Despite optimal management, periarrest bacterial translocation may worsen the outcome of cardiac arrest victims.

Extrahepatic complications to cirrhosis and portal hypertension: Haemodynamic and homeostatic aspects

In addition to complications relating to the liver, patients with cirrhosis and portal hypertension develop extrahepatic functional disturbances of multiple organ systems. This can be considered a multiple organ failure that involves the heart, lungs, kidneys, the immune systems, and other organ systems. Progressive fibrosis of the liver and subsequent metabolic impairment leads to a systemic and splanchnic arteriolar vasodilatation. This affects both the haemodynamic and functional homeostasis of many organs and largely determines the course of the disease. With the progression of the disease, the circulation becomes hyperdynamic with cardiac, pulmonary as well as renal consequences for dysfunction and reduced survival. Infections and a changed cardiac function known as cirrhotic cardiomyopathy may be involved in further aggravation of other complications such as renal failure precipitating the hepatorenal syndrome. Patients with end-stage liver disease and related complications as for example the hepatopulmonary syndrome can only radically be treated by liver transplantation. As a bridge to this treatment, knowledge on the mechanisms of the pathophysiology of complications is essential for the choice of vasoactive drugs, antibiotics, drugs with specific effects on fibrogenesis and inflammation, and drugs that target specific receptors.

Inferior right hepatic vein-preserving major right hepatectomy for hepatocellular carcinoma in patients with significant fibrosis or cirrhosis

BACKGROUND

Liver resection represents a most effective treatment for hepatocellular carcinoma (HCC). The extent of hepatectomy for HCC involves maintaining a tricky balance between radical resection of tumors and preservation of sufficient liver parenchyma. Generally, removal of the right hepatic vein often involves resection of the whole posterior right lobe, which may prevent patients with impaired liver function from maintaining a functional reserve and could also limit the future liver remnant from curative hepatectomy. As a common anatomic variation, preservation of the inferior right hepatic vein (IRHV) may enable preservation of liver segment 6, even when the right hepatic vein has to be removed. In the present study, we report our experience with IRHV-preserving major right hepatectomy.

METHODS

From February 2009 to December 2011, eight trisegmentectomies 5-7-8 and two segmentectomies 4-5-7-8 were performed with the IRHV-sparing technique on patients with HCC and significant fibrosis or cirrhosis. Data including demographic information, preoperative evaluations, postoperative outcomes, and follow-up results were collected and evaluated.

RESULTS

All patients survived and recovered from hepatectomy. The incidence of complications was higher in cirrhotic patients. The 1-year overall survival rate was 80 %, and the 1-year disease free survival rate was 60 %.

CONCLUSIONS

IRHV-preserving major right hepatectomy increases the resectability of HCC. Intraoperative ultrasonography is recommended to facilitate protection of the IRHV. This technique is safe with careful preoperative evaluation and meticulous perioperative care. The short-term outcome of IRHV-preserving liver resections is satisfactory.

Significance of serum procalcitonin as biomarker for detection of bacterial peritonitis: a systematic review and meta-analysis

Background

Bacterial peritonitis is serious disease and remains a diagnostic challenge for clinicians. Many studies have highlighted the potential usefulness of procalcitonin (PCT) for identification of bacterial peritonitis, however, the overall diagnostic value of PCT remains unclear. Therefore, we performed a meta-analysis to assess the accuracy of PCT for detection of bacterial peritonitis.

Methods

We performed a systematic searched in MEDLINE, EMBASE, SCOPUS, China Biology Medicine Database (CBM), China National Knowledge Infrastructure Database (CNKI) and Cochrane databases for trials that evaluated the diagnostic role of PCT for bacterial peritonitis. Sensitivity, specificity and other measures of accuracy of PCT were pooled using bivariate random effects models.

Results

Eighteen studies involving 1827 patients were included in the present meta-analysis. The pooled sensitivity and specificity of serum PCT for the diagnosis bacterial peritonitis were 0.83 (95% CI: 0.76–0.89) and 0.92 (95% CI: 0.87–0.96), respectively. The positive likelihood ratio was 11.06 (95% CI: 6.31–19.38), negative likelihood ratio was 0.18 (95% CI: 0.12–0.27) and diagnostic odds ratio (DOR) was 61.52 (95% CI: 27.58–137.21). The area under the receiver operating characteristic curve (AUROC) was 0.94. Use of a common PCT cut-off value could improve the DOR to 75.32 and the AUROC to 0.95. Analysis of the seven studies that measured serum C-reactive protein (CRP) indicated that PCT was more accurate than CRP for the diagnosis of bacterial peritonitis.

Conclusions

Our results indicate that PCT determination is a relatively sensitive and specific test for the diagnosis of bacterial peritonitis. However, with regard to methodological limitations and significant heterogeneity, medical decisions should be based on both clinical findings and PCT test results.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2334-14-452) contains supplementary material, which is available to authorized users.

Laboratory diagnostics of spontaneous bacterial peritonitis

The term peritonitis indicates an inflammatory process involving the peritoneum that is most frequently infectious in nature. Primary or spontaneous bacterial peritonitis (SBP) typically occurs when a bacterial infection spreads to the peritoneum across the gut wall or mesenteric lymphatics or, less frequently, from hematogenous transmission in combination with impaired immune system and in absence of an identified intra-abdominal source of infection or malignancy. The clinical presentation of SBP is variable. The condition may manifest as a relatively insidious colonization, without signs and symptoms, or may suddenly occur as a septic syndrome. Laboratory diagnostics play a pivotal role for timely and appropriate management of patients with bacterial peritonitis. It is now clearly established that polymorphonuclear leukocyte (PMN) in peritoneal fluid is the mainstay for the diagnosis, whereas the role of additional biochemical tests is rather controversial. Recent evidence also suggests that automatic cell counting in peritoneal fluid may be a reliable approach for early screening of patients. According to available clinical and laboratory data, we have developed a tentative algorithm for efficient diagnosis of SBP, which is based on a reasonable integration between optimization of human/economical resources and gradually increasing use of invasive and expensive testing. The proposed strategy entails, in sequential steps, serum procalcitonin testing, automated cell count in peritoneal fluid, manual cell count in peritoneal fluid, peritoneal fluid culture and bacterial DNA testing in peritoneal fluid.

A study on the position and etiology of infection in cirrhotic patients: A potential precipitating factor contributing to hepatic encephalopathy

Hepatic encephalopathy (HE) is a severe and high-mortality complication in cirrhotic patients. In this study, we analyzed infection, one of the common precipitating factors of HE in patients with cirrhosis, in order to identify common infection sites and the etiology. In addition, we aimed to identify information useful in the early prevention and effective treatment of HE. Ninety-two patients presenting with hepatitis B virus-related cirrhosis with HE (HBC-HE) and 45 patients presenting with alcoholic cirrhosis with HE (ALD-HE) were enrolled in this study. We collected and analyzed data concerning the precipitating factors of HE using blood tests, biochemical detection and bacterial culture to identify which precipitating factor was the most common. Fifty-three patients with HE (37 with HBC-HE and 16 with HBC-HE) had infection as the precipitating factor. These infections included respiratory tract infection (56.6%), intestinal tract infection (20.7%), peritoneal infection (17.0%) and urinary tract infection (5.7%). The white blood cell (WBC) counts increased in 17 cases (32.1%) and neutrophil (NEUT) numbers increased in 39 cases (73.6%), while WBC counts were lower in the patients with respiratory tract infection compared with those in the patients with infections at other sites (P<0.05). The levels of plasma ammonia were significantly higher in patients with intestinal tract infection than in those with other sites of infection (P<0.05). The proportions of patients with hyperammonemia, increased NEUT numbers, hyponatremia and low albumin were higher in the infection group compared with those in the non-infection group (P<0.05). Pneumococci and E. coli were common bacteria that induced infection in the respiratory tract and at other infection sites, respectively. Respiratory tract infection was identified to be the most common precipitating factor for HE.

Acute Fatal Peritonitis: A New Organism for Consideration

A 40-year-old man died suddenly and unexpectedly at home. His comorbid conditions included central diabetes insipidus, obesity, and hypertension. Autopsy revealed acute and chronic pancreatitis with an abscess and associated purulent peritonitis. Peritoneal fluid cultures grew Raoultella planticola and a light growth of Candida albicans. The organism isolated, R. planticola, is a waterborne bacterium with limited previous clinical isolates causing morbidity but no previously described mortality. Vitreous humor analysis demonstrated concomitant acute water intoxication complicating the decedent's diabetes insipidus. Discussion includes a review of the literature with a description of the eight previous cases of human infection with R. planticola, a recently described organism that was previously in the genus Klebsiella. The proposed fatal pathogenesis includes retrograde entry of the organism from the gastrointestinal tract via the pancreatic duct to the pancreas and subsequent peritonitis. This is the first reported fatality caused by this organism.

Tumor necrosis factor-α and interleukin-6 in cirrhotic patients with spontaneous bacterial peritonitis

AIM: To evaluate the role of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in cirrhotic patients who have hepatic and renal impairment with spontaneous bacterial peritonitis (SBP).

METHODS: We prospectively studied 120 cirrhotic patients with SBP and 80 cirrhotic patients with sterile ascitic fluid. They included 144 males and 56 females with ages ranging between 34 and 62 years. The diagnosis of cirrhosis was established by clinical and laboratory criteria that did not require histological confirmation. The severity of underlying liver disease was evaluated using Pugh’s modification of Child’s criteria (Child-Pugh scores). Ascitic fluid was sent to the laboratory for cell count, culture, sensitivity testing, and measurement of chemical elements (i.e., albumin, glucose). Specimens were inoculated into aerobic and anaerobic blood culture bottles. Serum and ascitic fluid were also collected in sterile tubes at study entry (before the initiation of antibiotic treatment) and 48 h later. Assays for TNF-α and IL-6 in the serum and ascitic fluid were performed with an immunoenzymometric assay using manufacture’s instructions.

RESULTS: Cytokine levels in serum and ascitic fluid were significantly higher in the patients with SBP. (plasma TNF-α: 135.35 ng/mL ± 11.21 ng/mL vs 92.86 ng/mL ± 17.56 ng/mL, P < 0.001; plasma IL-6: 32.30 pg/mL ± 7.07 pg/mL vs 12.11 pg/mL ± 6.53 pg/mL, P < 0.001; ascitic fluid TNF-α: 647.54 ± 107.11 ng/mL vs 238.43 ng/mL ± 65.42 ng/mL, P < 0.001); ascitic fluid IL-6: 132.84 ng/mL ± 34.13 vs 40.41 ± 12.85 pg/mL, P < 0.001). About 48 (40%) cirrhotic patients with SBP developed renal and hepatic impairment and showed significantly higher plasma and ascitic fluid cytokine levels at diagnosis of infection. [(plasma TNF-α: 176.58 ± 17.84 vs 135.35 ± 11.21 ng/mL) (P < 0.001) and (IL-6: 57.83 ± 7.85 vs 32.30 ± 7.07 pg/mL) (P < 0.001); ascitic fluid TNF-α: 958.39 ± 135.72 vs 647.54 ± 107.11 ng/mL, (P < 0.001), ascitic fluid IL-6: 654.74 ± 97.43 vs 132.84 ± 34.13 pg/mL, (P < 0.001)]. Twenty nine patients (60.4%) with SBP and renal impairment died whereas, only four patients (5.55%) with SBP but without renal impairment died from gastrointestinal hemorrhage (P < 0.0005).

CONCLUSION: It appears that TNF-α production may enhance liver cell injury and lead to renal impairment. This correlated well with the poor prognosis and significantly increased mortality associated with SBP in cirrhotic patients.

Clinical significance of serum and ascitic levels of IL-10, IL-18 and endotoxin in cirrhotic patients with spontaneous bacterial peritonitis

AIM: To investigate the levels of interleukin-10 (IL-10), interleukin-18 (IL-18) and endotoxin in serum and ascitic fluid of cirrhotic patients with spontaneous bacterial peritonitis (SBP) and to analyze their clinical significance.

METHODS: Serum and ascitic levels of IL-10 and IL-18 were assayed by ELISA in 32 cases of sterile ascites (SA) and 45 cases of SBP, while endotoxin levels were measured by a chromogenic assay. A normal control group consisting of 20 healthy individuals was also included in the study.

RESULTS: Serum and ascitic levels of IL-10 (μg/L), IL-18 (μg/L) and endotoxin (Eu/mL) in SBP and SA patients were significantly higher than those in healthy individuals (180.422 ± 84.789, 455.781 ± 106.750 vs 36.065 ± 10.181; 744.378 ± 249.160, 571.094 ± 157.501 vs 82.850 ± 31.101; 0.377 ± 0.114, 0.276 ± 0.073 vs 0.087 ± 0.024, all P < 0.01). SBP patients had higher levels of IL-18 and endotoxin (especially ascitic level of IL-18) but lower level of IL-10 than SA patients. The levels of IL-10, IL-18 and endotoxin in ascites of SBP patients were higher than those in serum. Serum and ascitic levels of IL-10 (μg/L), IL-18 (μg/L) and endotoxin (Eu/mL) decreased significantly in SBP patients after therapy (155.600 ± 73.631 vs 180.422 ± 84.789; 249.510 ± 100.362 vs 579.711 ± 246.260; 610.133 ± 250.682 vs 744.378 ± 249.160; 811.020 ± 287.916 vs 1005.467 ± 286.552; 0.285 ± 0.104 vs 0.377 ± 0.114; 0.520 ± 0.193 vs 0.752 ± 0.302, all P < 0.01), and the decrease was more significant in ascites than in serum. Child-Pugh classification and Child-Pugh score also decreased significantly in SBP patients after therapy (Z = -5.72, P < 0.01; 8.98 ± 2.62 vs 11.13 ± 2.20, t = 12.39, P < 0.01).

CONCLUSION: IL-10, IL-18 and endotoxin play an important role in the pathogenesis of SBP. Detection of ascitic levels of IL-10, IL-18 and endotoxin may be used for early diagnosis, evaluation of treatment response, and prediction of prognosis in SBP patients.