Procalcitonin as a diagnostic marker for sepsis

Construction and efficacy evaluation of an early warning scoring system for septic shock in patients with digestive tract perforation: A retrospective cohort study

Objective

To establish an early warning scoring system for septic shock in patients with digestive tract perforation (DTP) and evaluate its diagnostic efficacy.

Methods

Patients with surgically confirmed or clinically diagnosed DTP admitted to the Department of Intensive Care Medicine of Fujian Provincial Hospital from June 2012 to October 2021 were retrospectively analyzed. General demographic characteristics, perforation-related information, vital signs, common laboratory indicators, and common ICU scores (Glasgow Coma Scale score, Acute Physiology and Chronic Health Evaluation-II score,Sequential Organ Failure Assessment score) were collected. The patients were divided into shock group and non-shock group according to whether the patients had septic shock during hospitalization. The risk factors of septic shock were screened by basic statistical analysis and multivariate Logistic regression analysis. The receiver operating characteristic curve was drawn to determine the cut-off value of the continuous indicators and discretized with reference to clinic, and the corresponding score was set according to the β regression coefficient of each variable.

Results

A total of 176 patients with DTP were included. The average age of the patients was 64.13 ± 14.67 years old, and 74.40% were males. The incidence of septic shock was 30.11% (53/176). Multivariate Logistic regression analysis showed that the highest heart rate≥105 beats/min, Glasgow Coma Scale score≤14 points, lactic acid≥5.75 mmol/L, procalcitonin≥41.47 ug/L, C-reactive protein≥222.5 mg/L were independent risk factors for septic shock in patients with DTP. The total score of clinical diagnostic scoring system of septic shock in patients with DTP was 6 points, including the highest heart rate≥105 beats/min (1 point), lactic acid≥5.75 mmol/L (two points), procalcitonin≥41.47 ug/L (one point), C-reactive protein≥222.5 mg/L (1 point), and Glasgow Coma Scale score≤14 points (1 point). The area under ROC curve (AUC) of this scoring system was 0.789 and the 95% confidence interval was 0.717–0.860 (P < 0.001); when the optimal cut-off value was 2.5, the sensitivity and specificity were 54.70 and 87.80%, respectively.

Conclusion

This new score system has its certain clinical value and has important guiding significance for clinicians to judge the prognosis of patients with DTP in time.

Negative surgical exploration in suspected gastrointestinal perforation: trend, preoperative predictors, and etiologies

Background

Despite the rapid improvement of clinical science and imaging technology including computed tomography, the entity of negative surgical exploration in suspected gastrointestinal perforation (N-GIP) still exist. However, few studies have focused on this issue and most studies are case reports. We undertook this study to investigate the rates of N-GIP, and explore a set of possible preoperative predictors associated with N-GIP.

Methods

This was a retrospective study performed at the department of general surgery in our treatment center. All patients included were suspected gastrointestinal perforation (GIP) cases, aged 14 years and over, and underwent emergency surgery between 2009 and 2019. A predictive multivariable model of the presence of N-GIP was developed using logistic regression analysis.

Results

A total of 973 patients were identified and 30 (3.1%) were found to have no evidence of perforated gastrointestinal tract. The mean age of patients was 59.74 (range, 14–97) years, and 67.2 percent of the patients were males. The rates of N-GIP did not have a significant change over time (P=0.212 for trend). In multivariable analysis, absence of generalized peritonitis, duration of abdominal pain >19.6 hours, and neutrophil-to-lymphocyte ratio (NLR) <3.80 were significant predictors of N-GIP. N-GIP was more common in patients with gastrointestinal tumors and foreign bodies. Five patients (16.7%) in N-GIP group experienced complications and the 90-day mortality rate was 6.7%.

Conclusions

The rates of N-GIP did not change significantly over time. N-GIP was associated with the absence of generalized peritonitis, duration of abdominal pain >19.6 hours, and NLR <3.80.

Heparin-binding protein and procalcitonin in the diagnosis of pathogens causing community-acquired pneumonia in adult patients: a retrospective study

The performance of inflammatory markers in community-acquired pneumonia (CAP) caused by different pathogens has not been fully studied. We sought to find the differences in the concentrations of procalcitonin (PCT) and heparin-binding protein (HBP) between patients with CAP caused by different pathogens. We enrolled 162 patients with CAP, divided into three groups on the basis of bacterial (n = 108), fungal (n = 21) and viral (n = 33) infection. Complete leukocyte counts and the concentration of HBP and PCT were measured, and the differences were compared with nonparametric tests. The receiver operating characteristic (ROC) curve was used to evaluate the significant differences in the sensitivity and specificity of the indicators. The leukocyte and neutrophils counts and the concentrations of HBP and PCT in the viral group were significantly lower than those in the other two groups (p < 0.001). The area under the ROC curve (AUC) of the concentration of HBP and PCT as well as leukocyte and neutrophils counts were 0.927, 0.892, 0.832 and 0.806 for distinguishing bacterial from viral infection, respectively. The best cut-off value was 20.05 ng/mL for HBP, with a sensitivity of 0.861 and specificity of 0.939. The best cut-off value was 0.195 ng/mL for PCT, with a sensitivity of 0.991 and specificity of 0.636. The best cut-off value was 5.195 × 10⁹/L and 4.000 × 10⁹/L for leukocyte and neutrophils counts, with sensitivity of 0.694 and 0.880 and specificity of 0.667 and 0.636, respectively. The AUC of HBP, PCT and leukocyte and neutrophil counts for distinguishing fungal from viral infection were 0.851, 0.883, 0.835 and 0.830, respectively. The best cut-off values were 29.950 ng/mL, 0.560 ng/mL, 5.265 × 10⁹/L and 3.850 × 10⁹/L, with sensitivity of 0.667, 0.714, 0.905 and 0.952 and specificity of 0.970, 0.879 0.667 and 0.606, respectively. There were no significant differences in the three indicators between the bacterial and fungal infection groups. The concentration of CRP showed no significant differences among the three groups. Consequently, the stronger immune response characterized by higher inflammation markers including HBP and PCT can help distinguish bacterial and fungal CAP from viral CAP.

Predicting and managing sepsis in burn patients: current perspectives

Modern burn care has led to unprecedented survival rates in burn patients whose injuries were fatal a few decades ago. Along with improved survival, new challenges have emerged in the management of burn patients. Infections top the list of the most common complication after burns, and sepsis is the leading cause of death in both adult and pediatric burn patients. The diagnosis and management of sepsis in burns is complex as a tremendous hypermetabolic response secondary to burn injury can be superimposed on systemic infection, leading to organ dysfunction. The management of a septic burn patient represents a challenging scenario that is commonly encountered by providers caring for burn patients despite preventive efforts. Here, we discuss the current perspectives in the diagnosis and treatment of sepsis and septic shock in burn patients.

Procalcitionin as a diagnostic marker to distinguish upper and lower gastrointestinal perforation

AIM

To assess the accuracy of serum procalcitionin (PCT) as a diagnostic marker in verifying upper and lower gastrointestinal perforation (GIP).

METHODS

This retrospective study included 46 patients from the surgical intensive care unit (ICU) of the Second Affiliated Hospital of Harbin Medical University who were confirmed to have GIP between June 2013 and December 2016. Demographic and clinical patient data were recorded on admission to ICU. Patients were divided into upper (n = 19) and lower (n = 27) GIP groups according to the perforation site (above or below Treitz ligament). PCT and WBC count was obtained before laparotomy and then compared between groups. Meanwhile, the diagnostic accuracy of PCT was analyzed.

RESULTS

Patients with lower GIP exhibited significantly higher APACHE II score, SOFA score and serum PCT level than patients with upper GIP (P = 0.017, 0.004, and 0.001, respectively). There was a significant positive correlation between serum PCT level and APACHE II score or SOFA score (r = 0.715 and r = 0.611, respectively), while there was a significant negative correlation between serum PCT level and prognosis (r = -0.414). WBC count was not significantly different between the two groups, and WBC count showed no significant correlation with serum PCT level, APACHE II score, SOFA score or prognosis. The area under the receiver operating characteristic curve of PCT level to distinguish upper or lower GIP was 0.778. Patients with a serum PCT level above 17.94 ng/dL had a high likelihood of lower GIP, with a sensitivity of 100% and a specificity of 42.1%.

CONCLUSION

Serum PCT level is a reliable and accurate diagnostic marker in identifying upper or lower GIP before laparotomy.

Neutrophil-to-lymphocyte ratio as a prognostic marker in critically-ill septic patients

BACKGROUND

We evaluated the associations between the neutrophil-to-lymphocyte ratio (NLR) or changes in NLR and outcomes in septic patients.

METHODS

Patients who met the criteria for severe sepsis or septic shock were categorized into five groups according to the quintile of initial NLR value. We defined two risk groups according to NLR value and changes in NLR during the first two days (defined as the persistently low NLR group and the persistently high NLR group). The primary outcome was 28-day mortality.

RESULTS

A total of 1395 patients were included. The median initial NLR values from Quintile 1 to Quintile 5 were as follows: 0.2 (IQR [interquartile range], 0.1-0.7), 3.4 (IQR, 2.6-4.7), 8.6 (IQR, 7.1-9.9), 15.4 (IQR, 13.3-17.8), and 31.0 (IQR, 24.6-46.8), respectively. The 28-day mortality values for the same groups were as follows: 24.4%, 12.2%, 11.1%, 11.8%, and 16.1% (P<.01). Cox regression analysis showed that inclusion in Quintile 1 or Quintile 5 was a significant risk factor predicting 28-day mortality compared to Quintile 3 (adjusted hazard ratio [HR]: 1.79 (95% confidence interval [CI], 1.15-2.78) in Quintile 1; 1.67 (95% CI, 1.04-2.66) in Quintile 5). The analysis indicated that persistently low NLR (adjusted HR: 2.25, 95% CI, 1.63-3.11) and persistently high NLR (adjusted HR: 2.65, 95% CI, 1.64-4.29) were significant risk factors.

CONCLUSIONS

In summary, the initial NLR measured at ED admission was independently associated with 28-day mortality in patients with severe sepsis and septic shock. In addition, change in NLR may prove to be a valuable prognostic marker.

Human Neutrophil Lipocalin as a Superior Diagnostic Means To Distinguish between Acute Bacterial and Viral Infections

The distinction between causes of acute infections is a major clinical challenge. Current biomarkers, however, are not sufficiently accurate. Human neutrophil lipocalin (HNL) concentrations in serum or whole blood activated by formyl-methionine-leucine-phenylalanine (fMLP) were shown to distinguish acute infections of bacterial or viral cause with high accuracy. The aim was therefore to compare the clinical performance of HNL with currently used biomarkers. Seven hundred twenty-five subjects (144 healthy controls and 581 patients with signs and symptoms of acute infections) were included in the study. C-reactive protein (CRP), the expression of CD64 on neutrophils, procalcitonin (PCT), and blood neutrophil counts were measured by established techniques, and HNL concentrations were measured in whole-blood samples after activation with fMLP. All tested biomarkers were elevated in bacterial as opposed to viral infections (P < 0.001). CRP, PCT, and CD64 expression in neutrophils was elevated in viral infections compared to healthy controls (P < 0.001). In the distinction between healthy controls and patients with bacterial infections, the areas under the receiver operating characteristic (ROC) curves were >0.85 for all biomarkers, whereas for the distinction between bacterial and viral infections, only HNL concentration in fMLP-activated whole blood showed an area under the ROC curve (AUROC) of >0.90 and superior clinical performance. The clinical performance of HNL in fMLP-activated whole blood was superior to current biomarkers and similar to previous results of HNL in serum. The procedure can be adopted for point-of-care testing with response times of <15 min.

Clinical significance of serum procalcitonin in patients with ulcerative colitis

AIM: To investigate the association of serum procalcitonin (PCT) level with disease activity and inflammatory markers in ulcerative colitis (UC).

METHODS: Serum PCT levels, white blood cell count, platelet count, erythrocyte sedimentation rate (ESR), albumin, C-reactive protein (CRP) and interleukin-6 (IL-6) levels were analyzed in 31 patients with UC and 18 healthy volunteers. Severity assessments were based on the Truelove and Witts' severity index. Spearman's rank correlation and receiver operating characteristic (ROC) analysis were used to evaluate correlations between variables and diagnostic accuracy, respectively.

RESULTS: Serum PCT level in severe UC patients (n = 11, 0.426 μg/mL ± 0.506 μg/mL) was significantly higher than those in mild-to-moderate UC patients (n = 20, 0.079 μg/mL ± 0.085 μg/mL) and healthy volunteers (n = 18, 0.03 μg/mL ± 0.01 μg/mL) (P = 0.047, 0.027, respectively). Serum PCT level in UC patients was positively correlated with CRP levels, IL-6 levels and ESR, negatively with albumin levels (P < 0.05), but showed no statistically significant correlation with white blood cell count or platelet count (P > 0.05). PCT performed well in the prediction of UC, and was superior to CRP, ESR and white blood cell count for diagnosing severe UC. The area under the ROC curve was 0.895 (95%CI: 0.782-1.000, P < 0.001), 0.727 (95%CI: 0.548-0.906, P = 0.041), 0.856 (95%CI: 0.721-0.992, P = 0.001) and 0.665 (95%CI: 0.463-0.867, P = 0.138), respectively. A threshold of 0.1 μg/L for PCT may detect the most severe form of UC, and the sensitivity, specificity, predictive positive value and negative predictive value predictive were 90.91%, 80.00%, 71.43% and 94.12%, respectively.

CONCLUSION: Serum PCT level correlates with disease activity markers ESR and CRP in UC, and a cut-off of 0.1 μg/L could distinguish the most severe form of UC.