Intra-abdominal infection in acute pancreatitis in eastern China: microbiological features and a prediction model

Correlation between the gut microbiota characteristics of hosts with severe acute pancreatitis and secondary intra-abdominal infection

Objective

The objective of the study is to investigate the changes in the composition of intestinal microecology in severe acute pancreatitis (SAP) patients with or without intra-abdominal infection and also to analyze the expression of antibiotic resistance genes to provide evidence for early warning of infectious diseases and the rational use of antibiotics.

Methods

Twenty patients with SAP were enrolled in the study. According to whether the enrolled patients had a secondary intra-abdominal infection, they were divided into two groups, each consisting of 10 patients. Stool specimens were collected when the patients were admitted to the emergency intensive care unit (EICU), and nucleic acid extraction was performed. Next-generation gene sequencing was used to compare the differences in intestinal microflora diversity and drug resistance gene expression between the two groups.

Results

The gut microbiota of patients in the infection group exhibited distribution on multiple clustered branches with some intra-group heterogeneity, and their flora diversity was compromised. The infected group showed an enrichment of various opportunistic bacteria in the gut microbiota, along with a high number of metabolic functions, stress functions to external signals, and genes associated with pathogenesis. Drug resistance genes were expressed in the gut microbiota of both groups, but their abundance was significantly lower in the non-infected group.

Conclusion

The intestinal microbiota of patients in the infection group exhibited distribution on multiple clustered branches with some intra-group heterogeneity, and their flora diversity was compromised. Additionally, drug resistance genes were expressed in the gut microbiota of both groups, although their abundance was significantly lower in the non-infected group.

A new in-hospital mortality prediction nomogram for intensive care unit patients with acute pancreatitis

Introduction

Acute pancreatitis (AP) is a prevalent inflammatory disease that can lead to severe abdominal pain and multiple organ failure, potentially resulting in pancreatic necrosis and persistent dysfunction. A nomogram prediction model was developed to accurately evaluate the prognosis and provide therapy guidance to AP patients.

Material and methods

Retrospective data extraction was performed using MIMIC-IV, an open-source clinical database, to obtain 1344 AP patient records, of which the primary dataset included 1030 patients after the removal of repeated hospitalizations. The prediction of in-hospital mortality (IHM) used the least absolute shrinkage and selection operator (LASSO) regression model to optimize feature selection. A multivariate logistic regression analysis was used to build a prediction model incorporating the selected features, and the C-index, calibration plot, and decision curve analysis (DCA) were utilized to evaluate the discrimination, calibration, and clinical applicability of the prediction model.

Results

The nomogram utilized a combination of indicators, including the SAPS II score, RDW, MBP, RR, PTT, and fluid-electrolyte disorders. Impressively, the model exhibited a satisfactory diagnostic performance, with area under the curve values of 0.892 and 0.856 for the training cohort and internal validation, respectively. Moreover, the calibration plots and the Hosmer-Lemeshow goodness-of-fit (HL) test revealed a strong correlation between the predicted and actual outcomes (p = 0.73), further confirming the reliability of our model. Notably, the results of the decision curve analysis (DCA) highlighted the superiority of our model over previously described scoring methods in terms of net clinical benefit, solidifying its value in clinical applications.

Conclusions

Our novel nomogram is a simple tool for accurately predicting IHM in ICU patients with AP. Treatment methods that enhance the factors involved in the model may contribute to increased in-hospital survival for these ICU patients.

Detection of potential pathogen in pancreatic fluid aspiration with metagenomic next-generation sequencing in patients with suspected infected pancreatic necrosis

BACKGROUND

Timely and accurate microbial diagnosis is important in managing patients with infected pancreatic necrosis (IPN).

AIMS

To evaluate the diagnostic performance of Metagenomic next-generation sequencing (mNGS) in patients with suspected IPN.

METHODS

The clinical data of 40 patients with suspected IPN who underwent CT-guided pancreatic fluid aspiration were retrospectively analyzed. Microbial culture and mNGS were simultaneously applied to identify the potential pathogens. The diagnostic performance of the mNGS was assessed by sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The mNGS report can be obtained significantly earlier than culture methods (42 (36-62 h) vs. 60 (42-124 h), P = 0.032). Across all the study samples, seven species of bacteria and two species of fungi were reported accordingly to the culture results, while 22 species of bacteria and two species of fungi were detected by mNGS. The sensitivity, specificity, NPV, and PPV of mNGS were 88.0%, 100%, 83.33%, and 100%, respectively.

CONCLUSIONS

The diagnostic accuracy of mNGS in patients with suspected IPN is satisfactory. Moreover, mNGS may broaden the range of identifiable infectious pathogens and provide a more timely diagnosis.

Moderate level platelet count might be a good prognostic indicator for intra-abdominal infection in acute pancreatitis: A retrospective cohort study of 1,363 patients

Background

Early recognition of the risk factors is important for acute pancreatitis management. The aim of this study is to investigate the relationship between platelet count and clinical outcomes in patients with acute pancreatitis.

Methods

The data are collected from a university-affiliated hospital between January 2013 and December 2020. A generalized additive model and a two-piecewise linear regression model are used to estimate the association between platelet count and the risks of intra-abdominal infection, surgical intervention, in-hospital mortality, and length of hospital stay.

Results

Among the 1,363 patients, 99 (7.3%) patients suffered intra-abdominal infection, 190 (13.9%) patients underwent surgical intervention, and 38 (2.8%) patients died in the hospital. The median length of hospital stay is 21 days. Generalized additive model and two-piecewise linear regression analysis show that the risk of intra-abdominal infection decreases as the platelet count increases to 160 × 10⁹/L (OR: 0.991, 95% CI: 0.984-0.998, p = 0.015) and then increases as the platelet count levels up (OR: 1.007, 95% CI: 1.004-1.010, p < 0.001). The trend is similar to the risk of surgical intervention and length of hospital stay. Even though there seems a declining trend in mortality, no significant association is found after adjustment for potential confounders. Further analysis shows that changes in platelet count within the first 3 days after admission have no obvious association with clinical outcomes.

Conclusion

A platelet count of approximately 160 × 10⁹/L on admission is associated with the lowest risk of intra-abdominal infection, surgical intervention, and shortest hospital stay in patients with acute pancreatitis.

Evaluation of Inflammatory Infiltration in the Retroperitoneal Space of Acute Pancreatitis Using Computer Tomography and Its Correlation with Clinical Severity

This paper investigates the correlation between the degree and severity of CT inflammatory infiltration in the retroperitoneal space of acute pancreatitis (AP). A total of 113 patients were included based on diagnostic criteria. The general data of the patients and the relationship between the computed tomography severity index (CTSI) and pleural effusion (PE), involvement, degree of inflammatory infiltration of retroperitoneal space (RPS), number of peripancreatic effusion sites, and degree of pancreatic necrosis on contrast-enhanced CT at different times were studied. The results showed that the mean age of onset in females was later than that in males; 62 cases involved RPS to varying degrees, with a positive rate of 54.9% (62/113), and the total involvement rates of only the anterior pararenal space (APS); both APS and perirenal space (PS); and APS, PS, and posterior pararenal space (PPS) were 46.9% (53/113), 53.1% (60/113), and 17.7% (20/113), respectively. The degree of inflammatory infiltration in the RPS worsened with the increase in CTSI score; the incidence of PE was higher in the group greater than 48 hours than in the group less than 48 hours; necrosis >50% grade was predominant (43.2%) 5 to 6 days after onset, with a higher detection rate than other time periods (P < 0.05). Thus, when the PPS was involved, the patient's condition can be treated as severe acute pancreatitis (SAP); the higher the degree of inflammatory infiltration in the retroperitoneum, the higher the severity of AP. Enhanced CT examination 5 to 6 days after onset in patients with AP revealed the greatest extent of pancreatic necrosis.

Predicting persistent organ failure on admission in patients with acute pancreatitis: development and validation of a mobile nomogram

BACKGROUND

Early prediction of persistent organ failure (POF) is important for triage and timely treatment of patients with acute pancreatitis (AP).

METHODS

All AP patients were consecutively admitted within 48 h of symptom onset. A nomogram was developed to predict POF on admission using data from a retrospective training cohort, validated by two prospective cohorts. The clinical utility of the nomogram was defined by concordance index (C-index), decision curve analysis (DCA), and clinical impact curve (CIC), while the performance by post-test probability.

RESULTS

There were 816, 398, and 880 patients in the training, internal and external validation cohorts, respectively. Six independent predictors determined by logistic regression analysis were age, respiratory rate, albumin, lactate dehydrogenase, oxygen support, and pleural effusion and were included in the nomogram (web-based calculator: https://shina.shinyapps.io/DynNomapp/). This nomogram had reasonable predictive ability (C-indexes 0.88/0.91/0.81 for each cohort) and promising clinical utility (DCA and CIC). The nomogram had a positive likelihood ratio and post-test probability of developing POF in the training, internal and external validation cohorts of 4.26/31.7%, 7.89/39.1%, and 2.75/41%, respectively, superior or equal to other prognostic scores.

CONCLUSIONS

This nomogram can predict POF of AP patients and should be considered for clinical practice and trial allocation.

Clinical Value of Neutrophil CD64 Index, PCT, and CRP in Acute Pancreatitis Complicated with Abdominal Infection

Objective: To study the clinical diagnostic value of neutrophil CD64 index, PCT, and CRP in patients with acute pancreatitis with abdominal infection. Methods: A number of patients with acute pancreatitis (n = 234) participated in the study. According to the infection and health conditions, they were further divided into the non-infection group (n = 122), infection group (n = 78), and sepsis group (n = 34), and 40 healthy subjects were selected in the control group (n = 40). Expression levels of infection indexes, such as CD64 index, PCT, and CRP, were detected and compared. ROC curves were drawn to compare the efficacy of each index in the diagnosis of acute pancreatitis with abdominal infection and sepsis. The study was retrospectively registered under the China Clinical Trial Registry as a trial number ChiCTR2100054308. Results: All indexes were significantly higher in three clinical groups than the healthy control group (p < 0.05). The CD64 index, CD64 positive rate, and PCT in the infected group were significantly higher than those in the uninfected group (ALL p < 0.05). The PCT of patients infected with Gram-negative bacteria was significantly higher than that of Gram-positive bacteria-infected patients (p < 0.05). CD64 index had the best diagnostic efficiency for acute pancreatitis infection, with 82.14% sensitivity, 88.51% specificity, and 0.707 Youden indexes. The CD64 Youden index (0.780) for sepsis diagnosis was the highest, while the AUC of PCT was the highest (0.897). Conclusion: CD64 index combined with PCT has good sensitivity and specificity in diagnosing acute pancreatitis infection and sepsis.

Early Versus Delayed Enteral Feeding in Predicted Severe Acute Gallstone Pancreatitis: A Retrospective Study

Background

The optimal timing of enteral nutrition (EN) initiation in predicted severe acute gallstone pancreatitis (SAGP) and its influence on disease outcomes are not well known.

Methods

We conducted a retrospective study of patients with predicted SAGP treated with endoscopic retrograde cholangiopancreatography and EN. The patients were classified into two groups according to the timing of EN initiation after admission: within 48 h, and more than 48 h. The primary outcome was in-hospital mortality. The secondary outcomes were length of hospital stay, need for intensive care admission, need for surgical intervention, improvements in blood test results after 7-10 days of EN, incidence of pancreatic necrosis and infection, and hospital care costs. The microbiological profiles of infectious complications were also evaluated.

Results

Of the 98 patients, 31 and 67 started EN within 48 h, and more than 48 h after admission, respectively. Early EN was associated with a decrease in in-hospital mortality (0 vs. 11.9%; p=0.045), length of hospital stay (median:18 vs. 27 days; p=0.001), need for intensive care admission (3.2% vs. 20.9%; p=0.032), and hospital care costs (median:9,289 vs. 13,518 US$; p=0.007), compared to delayed EN. Moreover, early EN for 7-10 days had more beneficial effects on blood test results than delayed EN, including total protein (p=0.03) and CRP (p=0.006) levels. However, the need for surgical intervention and incidence of pancreatic necrosis did not differ between the two groups. In our study, Gram-negative bacteria were the main responsible pathogens (50.5%). Infection with multidrug-resistant organisms (MDRO) was found in 19.4% of the patients. The most common MDRO was MDR Enterococcus faecium. Early EN was not superior in reducing incidence of infected pancreatic necrosis, bacteremia, polymicrobial infection, or MDROs.

Conclusions

In patients with predicted SAGP, early EN is associated with a decrease in in-hospital mortality, length of hospital stay, need of intensive care admission, and hospital care costs, compared to delayed EN. There are no significant benefits of early EN in reducing the rate of infection-related complications. Further studies with larger sample sizes are warranted.