Influence of renal dysfunction on the accuracy of procalcitonin for the diagnosis of postoperative infection after vascular surgery:

Biomarkers in pulmonary infections: a clinical approach

Severe acute respiratory infections, such as community-acquired pneumonia, hospital-acquired pneumonia, and ventilator-associated pneumonia, constitute frequent and lethal pulmonary infections in the intensive care unit (ICU). Despite optimal management with early appropriate empiric antimicrobial therapy and adequate supportive care, mortality remains high, in part attributable to the aging, growing number of comorbidities, and rising rates of multidrug resistance pathogens. Biomarkers have the potential to offer additional information that may further improve the management and outcome of pulmonary infections. Available pathogen-specific biomarkers, for example, Streptococcus pneumoniae urinary antigen test and galactomannan, can be helpful in the microbiologic diagnosis of pulmonary infection in ICU patients, improving the timing and appropriateness of empiric antimicrobial therapy since these tests have a short turnaround time in comparison to classic microbiology. On the other hand, host-response biomarkers, for example, C-reactive protein and procalcitonin, used in conjunction with the clinical data, may be useful in the diagnosis and prediction of pulmonary infections, monitoring the response to treatment, and guiding duration of antimicrobial therapy. The assessment of serial measurements overtime, kinetics of biomarkers, is more informative than a single value. The appropriate utilization of accurate pathogen-specific and host-response biomarkers may benefit clinical decision-making at the bedside and optimize antimicrobial stewardship.

Long non‑coding RNAs MALAT1, NEAT1 and DSCR4 can be serum biomarkers in predicting urosepsis occurrence and reflect disease severity

Sepsis commonly occurs in patients with serious infections. It severely threatens the health of patients and has very high mortality rates. Urosepsis is a type of sepsis in which the serious infection originates from the urinary system. Early diagnosis of the occurrence and severity of urogenital sepsis is crucial for improving patient prognosis. Long noncoding RNAs (LncRNAs) play important roles in the occurrence of a number of diseases, including sepsis, and can be potential biomarkers that predict disease development. The present study aimed to discover potential LncRNAs that can predict the occurrence of urosepsis. RNA-sequence data from patients with sepsis from the GEO database was analyzed and LncRNAs associated with sepsis were identified. The expression of LncRNAs associated with sepsis was tested in clinical urosepsis samples. Finally, the value of these LncRNAs in predicting urosepsis was verified using clinical samples. From the GEO database a total of nine LncRNAs (MALAT1, NEAT1, RMRP, LncIRX5, LINC01742, DSCR4, C22ORF34, LINC00381, and LINC01102) were identified that had expression changes corresponding with the occurrence of sepsis. Specifically, MALAT1, NEAT1 and DSCR4 revealed differential expression in patients with urosepsis. Moreover, MALAT1, and DSCR4 were shown to be significant risk indicators for urosepsis, and NEAT1 was shown to reflect disease severity. Therefore, the present study indicated that the LncRNAs, MALAT1, NEAT1 and DSCR4 can reflect the occurrence and severity of urosepsis and may act as potential biomarkers.

The Role of Biomarkers in the Diagnosis and Management of Pneumonia

Biomarkers are used in the diagnosis, severity determination, and prognosis for patients with community-acquired pneumonia (CAP). Selected biomarkers may indicate a bacterial infection and need for antibiotic therapy (C-reactive protein, procalcitonin, soluble triggering receptor expressed on myeloid cells). Biomarkers can differentiate CAP patients who require hospital admission and severe CAP requiring intensive care unit admission. Biomarker-guided antibiotic therapy may limit antibiotic exposure without compromising outcome and thus improve antibiotic stewardship. The authors discuss the role of biomarkers in diagnosing, determining severity, defining the prognosis, and limiting antibiotic exposure in CAP and ventilator-associated pneumonia patients.

Sepsis-mediated renal dysfunction: Pathophysiology, biomarkers and role of phytoconstituents in its management

Sepsis has evolved as an enormous health issue amongst critically ill patients. It is a major risk factor that results in multiple organ failure and shock. Acute kidney injury (AKI) is one of the most frequent complications underlying sepsis, which portends a heavy burden of mortality and morbidity. Thus, the present review is aimed to provide an insight into the recent progression in the molecular mechanisms targeting dysregulated immune response and cellular dysfunction involved in the development of sepsis-associated AKI, accentuating the phytoconstituents as eligible candidates for attenuating the onset and progression of sepsis-associated AKI. The pathogenesis of sepsis-mediated AKI entails a complicated mechanism and is likely to involve a distinct constellation of hemodynamic, inflammatory, and immune mechanisms. Novel biomarkers like neutrophil gelatinase-associated lipocalin, soluble triggering receptor expressed on myeloid cells 1, procalcitonin, alpha-1-microglobulin, and presepsin can help in a more sensitive diagnosis of sepsis-associated AKI. Many bioactive compounds like curcumin, resveratrol, baicalin, quercetin, and polydatin are reported to play an important role in the prevention and management of sepsis-associated AKI by decreasing serum creatinine, blood urea nitrogen, cystatin C, lipid peroxidation, oxidative stress, IL-1β, TNF-α, NF-κB, and increasing the activity of antioxidant enzymes and level of PPARγ. The plant bioactive compounds could be developed into a drug-developing candidate in managing sepsis-mediated acute kidney injury after detailed follow-up studies. Lastly, the gut-kidney axis may be a more promising therapeutic target against the onset of septic AKI, but a deeper understanding of the molecular pathways is still required.

The association between procalcitonin and acute kidney injury in patients stung by wasps

Introduction: The aim of this study was to investigate the status of serum procalcitonin (PCT) in patients stung by wasps and evaluate the association between PCT levels and acute kidney injury (AKI). Methods: Patients stung by wasps admitted to two tertiary hospitals between January 2017 and December 2020 were screened for enrollment. We evaluated serum PCT levels on admission in patients stung by wasps. The patients were divided into an AKI group and a non-AKI group. A logistic regression model was used to analyze the association between PCT status and AKI. The performance of PCT concentrations in predicting the occurrence of AKI was evaluated by the area under the receiver operating characteristic curve (AUROC). Results: A total of 138 patients were enrolled, and 66 patients suffered AKI. PCT levels were elevated in 78.99% of patients stung by wasps. Nearly half of the patients (47.83%) developed AKI. PCT levels were correlated with creatinine levels on admission (r = 0.787, 95% CI: 0.713-0.844). PCT levels in patients with AKI were higher than those in patients without AKI (p < 0.001). After adjustment for covariates, PCT levels on admission were independently associated with AKI (OR: 1.575, 95% CI: 1.071-2.317, p = 0.021). The AUROC of PCT levels on admission was 0.837 (95% CI, 0.771-0.902, p < 0.001). A PCT level of 0.57 μg/L was the cutoff for maximizing the Youden index; the specificity was 79.45%, and the sensitivity was 73.43%. Conclusion: Serum PCT levels may be a potential biomarker of AKI in patients stung by wasps.

How to use biomarkers of infection or sepsis at the bedside: guide to clinicians

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. In this context, biomarkers could be considered as indicators of either infection or dysregulated host response or response to treatment and/or aid clinicians to prognosticate patient risk. More than 250 biomarkers have been identified and evaluated over the last few decades, but no biomarker accurately differentiates between sepsis and sepsis-like syndrome. Published data support the use of biomarkers for pathogen identification, clinical diagnosis, and optimization of antibiotic treatment. In this narrative review, we highlight how clinicians could improve the use of pathogen-specific and of the most used host-response biomarkers, procalcitonin and C-reactive protein, to improve the clinical care of patients with sepsis. Biomarker kinetics are more useful than single values in predicting sepsis, when making the diagnosis and assessing the response to antibiotic therapy. Finally, integrated biomarker-guided algorithms may hold promise to improve both the diagnosis and prognosis of sepsis. Herein, we provide current data on the clinical utility of pathogen-specific and host-response biomarkers, offer guidance on how to optimize their use, and propose the needs for future research.

Influence of Renal Dysfunction on the Differential Behaviour of Procalcitonin for the Diagnosis of Postoperative Infection in Cardiac Surgery

Background: procalcitonin is a valuable marker in the diagnosis of bacterial infections; however, the impairment of renal function can influence its diagnostic precision. The objective of this study is to evaluate the differential behaviour of procalcitonin, as well as its usefulness in the diagnosis of postoperative pulmonary infection after cardiac surgery, depending on the presence or absence of impaired renal function. Materials and methods: A total of 805 adult patients undergoing cardiac surgery with extracorporeal circulation (CBP) were prospectively recruited, comparing the behaviour of biomarkers between the groups with and without postoperative pneumonia and according to the presence or absence of renal dysfunction. Results: Pulmonary infection was diagnosed in 42 patients (5.21%). In total, 228 patients (28.32%) presented postoperative renal dysfunction. Procalcitonin was significantly higher in infected patients, even in the presence of renal dysfunction. The optimal procalcitonin threshold differed markedly in patients with renal dysfunction compared to patients without renal dysfunction (1 vs. 0.78 ng/mL p < 0.05). The diagnostic accuracy of procalcitonin increased significantly when the procalcitonin threshold was adapted to renal function. Conclusions: Procalcitonin is an accurate marker of postoperative infection in cardiac surgery, even in the presence of renal dysfunction. Renal function is an important determinant of procalcitonin levels and, therefore, its diagnostic thresholds must be adapted in the presence of renal dysfunction.

Procalcitonin and High APACHE (Acute Physiological and Chronic Health Evaluation) Level Are Associated with the Course of Acute Kidney Injury in Patients with SARS-CoV-2

BACKGROUND

Acute kidney injury (AKI) is associated with poor outcomes in patients infected with SARS-CoV-2. Sepsis, direct injury to kidney cells by the virus, and severe systemic inflammation are mechanisms implicated in its development. We investigated the association between inflammatory markers (C-reactive protein, procalcitonin, D-dimer, lactate dehydrogenase, and ferritin) in patients infected with SARS-CoV-2 and the development of AKI.

METHODS

A prospective cohort study performed at the Civil Hospital (Dr. Juan I. Menchaca) Guadalajara, Mexico, included patients aged >18 years with a diagnosis of SARS-CoV-2 pneumonia confirmed by RT-PCR and who did or did not present with AKI (KDIGO) while hospitalized. Biomarkers of inflammation were recorded, and kidney function was estimated using the CKD-EPI formula.

RESULTS

291 patients were included (68% males; average age, 57 years). The incidence of AKI was 40.5% (118 patients); 21% developed stage 1 AKI, 6% developed stage 2 AKI, and 14% developed stage 3 AKI. The development of AKI was associated with higher phosphate (p = 0.002) (RR 1.39, CI 95% 1.13-1.72), high procalcitonin levels at hospital admission (p = 0.005) (RR 2.09, CI 95% 1.26-3.50), and high APACHE scores (p = 0.011) (RR 2.0, CI 95% 1.17-3.40). The survival analysis free of AKI according to procalcitonin levels and APACHE scores demonstrated a lower survival in patients with procalcitonin >0.5 ng/ml (p = 0.001) and APACHE >15 points (p = 0.004).

CONCLUSIONS

Phosphate, high procalcitonin levels, and APACHE levels >15 were predictors of AKI development in patients hospitalized with COVID-19.

Presepsin as a predictor of septic shock in patients with urinary tract infection

Background

Recently, presepsin has been reported to be a useful biomarker for early diagnosis of sepsis and evaluation of prognosis in septic patients. However, few reports have evaluated its usefulness in patients with urinary tract infections (UTI). This study aimed to evaluate whether presepsin could be a valuable marker for detecting severe sepsis, and whether it could predict the therapeutic course in patients with UTI compared with markers already used: procalcitonin (PCT) and C-reactive protein (CRP).

Methods

From April 2014 to December 2016, a total of 50 patients with urinary tract infections admitted to Gunma university hospital were enrolled in this study. Vital signs, presepsin, PCT, CRP, white blood cell (WBC) count, causative agents of urinary-tract infections, and other data were evaluated on the enrollment, third, and fifth days. The patients were divided into two groups: with (n = 11) or without (n = 39) septic shock on the enrollment day, and with (n = 7) or without (n = 43) sepsis on the fifth day, respectively. Presepsin was evaluated as a biomarker for systemic inflammatory response syndrome (SIRS) or septic shock.

Results

Regarding the enrollment day, there was no significant difference of presepsin between the SIRS and non-SIRS groups (p = 0.276). The median value of presepsin (pg/mL) was significantly higher in the septic shock group (p < 0.001). Multivariate logistic regression analysis showed that presepsin (≥ 500 pg/ml) was an independent risk factor for septic shock (p = 0.007). ROC curve for diagnosing septic shock indicated an area under the curve (AUC) of 0.881 for presepsin (vs. 0.690, 0.583, and 0.527 for PCT, CRP and WBC, respectively). Regarding the 5th day after admission, the median presepsin value on the enrollment day was significantly higher in the SIRS groups than in the non-SIRS groups (p = 0.006). On the other hand, PCT (≥ 2 ng/ml) on the enrollment day was an independent risk factor for SIRS. ROC curve for diagnosing sepsis on the fifth day indicated an AUC of 0.837 for PCT (vs. 0.817, 0.811, and 0.802 for presepsin, CRP, and WBC, respectively).

Conclusions

This study showed that presepsin may be a good marker for diagnosing septic shock based on admission data in patients with UTI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00906-4.

Association between admission serum procalcitonin and the occurrence of acute kidney injury in patients with septic shock: A retrospective cohort study

BACKGROUND

Procalcitonin (PCT) is an effective and sensitive diagnostic biomarker that can facilitate the early detection of infection and septicemia, but whether it can similarly be utilized to predict the development of acute kidney injury (AKI) in patients suffering from septic shock remains to be established. Herein, the relationship between serum PCT at admission and the onset of AKI in septic shock patients was thus evaluated following adjustment for other potential covariates.

METHODS

This was a retrospective cohort study of 303 septic shock patients treated in a Chinese hospital between May 2015 and May 2019. All patients in whom PCT levels were measured on admission and who did not exhibit AKI or chronic kidney disease at the time of admission were assessed for AKI development within one week following intensive care unit (ICU) admission as per the KDIGO criteria. The relationship between serum PCT at admission and AKI incidence was then assessed for these patients.

RESULTS

These 303 patients were an average of 64 years old, and were 59.7% male. Of these patients, 50.5% developed AKI within the first 7 days following ICU admission. A dully-adjusted binary logistic regression analysis revealed PCT levels at admission to be associated with AKI following adjustment for potential confounding factors (odds ratio (OR) = 1.01, 95%CI (1.01,1.02), p = 0.0007). Receiver operating characteristic curve analysis further indicated that a PCT cutoff level of 52.59 ng/ml at admission was able to predict the incidence of AKI with respective sensitivity and specificity values of 50% and 84%. Interaction analysis revealed no significant interactive relationship between PCT and AKI, suggesting that serum PCT levels represent an early predictor of AKI incidence in septic shock patients.

CONCLUSIONS

Serum PCT at the time of admission can be used as a predictor of AKI in patients suffering from septic shock.

Predictive Ability of Procalcitonin for Acute Kidney Injury: A Narrative Review Focusing on the Interference of Infection

Acute kidney injury (AKI) is a common yet complicated clinical entity with high morbidity and mortality. An essential strategy to improve AKI patients’ prognoses is finding optimal biomarkers to identify AKI in a timely manner. Procalcitonin (PCT), a well-recognized biomarker for diagnosing infection and guiding antibiotics therapy, has been proposed to predict AKI development and recovery in many clinical settings. The current review provides comprehensive and updated information from relevant studies to evaluate PCT’s AKI-predictive ability and the influence of infection on this predictive ability. PCT has demonstrated optimal predictive ability for AKI in various populations irrespective of infection. However, the predictive ability seems to be blunted by infection since infection and inflammation have a more potent influence than AKI on PCT elevation. We furthermore explain the complicated association between elevated PCT levels and AKI in infection and inflammation situations and recommend directions for further investigations to clarify the essential issue. In conclusion, although conflicting data exist, serum PCT level is a potential biomarker for predicting AKI in many clinical settings regardless of infection. Nevertheless, further studies are warranted to clarify the association between PCT, infection, and AKI and to confirm the utilization of PCT for AKI prediction.

Meta-analysis of procalcitonin as a predictor for acute kidney injury

BACKGROUND

Procalcitonin (PCT) was used for predicting the development of acute kidney injury (AKI) in several studies recently. We aimed to investigate the accuracy of PCT for predicting AKI in this study.

METHODS

Studies that assessed the predictive performance of PCT for the development of AKI in adult patients were searched from Medline, Embase, and the Cochrane Library from inception to June 2020. We calculated the pooled sensitivities and specificities and the area under the summary receiver-operating characteristic (SROC) curves. I2 was used to test the heterogeneity and the potential heterogeneity was investigated by meta-regression.

RESULTS

In total, 9 of 119 studies with 4852 patients were included, 1272 were diagnosed with AKI. In the overall analysis, the area under the SROC curve was 0.82 (95% CI, 0.79-0.85) and the pooled sensitivity and specificity were 0.76 (95% confidence interval [CI], 0.64-0.85) and 0.75 (95% CI, 0.61-0.86), respectively. In the subgroup analysis among septic patients, the pooled sensitivity and specificity were 0.59 (95% CI, 0.29-0.84) and 0.53 (95% CI, 0.31-0.74), and the area under the SROC was 0.57 (95% CI, 0.53-0.62).

CONCLUSION

PCT may be a potential predictor for the development of AKI.

Independent Predictive Ability of Procalcitonin of Acute Kidney Injury among Critically Ill Patients

It is unclear whether serum procalcitonin (PCT) levels rise in patients with acute kidney injury (AKI), and it is also unclear whether the elevation of PCT levels in this setting is independent of the existence of infection and impaired renal clearance. We conducted a retrospective study in a regional teaching hospital in Taiwan to evaluate the AKI-predictive ability of serum PCT among critically ill patients. We enrolled 330 patients (mean age, 70.5 ± 16.4 years; 57.0% men) who were admitted to the intensive care unit (ICU) from 1 July 2016, to 31 December 2016, and who had serum PCT measurement performed within 24 h after ICU admission. We used the generalized additive model and generalized linear model to evaluate the association of serum PCT levels and renal function variables. In addition, we used the multivariate logistic regression method to demonstrate serum PCT level as an independent predictor of AKI in both the non-infected patients (odds ratio (OR) = 1.38, 95% confidence interval (CI) = 1.12–1.71, p = 0.003) and the infected patients (OR = 1.23, 95% CI = 1.03–1.46, p = 0.020). In conclusion, serum PCT level at ICU admission is an independent predictor of developing AKI irrespective of infection among critically ill patients.

Procalcitonin: A promising tool or just another overhyped test?

Sepsis is the leading cause of death worldwide. Timely administration of antibiotics is recognized as the cornerstone in the management of sepsis. However, inappropriate use of antibiotics may lead to adverse effects and the selection of drug-resistant pathogens. Microbiological cultures remain the gold standard to diagnose infection despite their low sensitivity and the intrinsic delay to obtain the results. Certain biomarkers have the benefit of rapid turnover, potentially providing an advantage in timely diagnosis leading to accurate treatment. Over the last few decades, there is an ongoing quest for the ideal biomarker in sepsis. Procalcitonin (PCT), when used alone or alongside additional clinical information, has shown to be a promising tool to aid in the diagnosis and management of patients with sepsis. In February 2017, the Food and Drug Administration (FDA) approved the use of PCT to guide antibiotic treatment in lower respiratory tract infections and sepsis. Despite a good negative predictive value for bacterial infection, the utility of PCT-guided antibiotic initiation is conflicting at best. On the other hand, the use of PCT-guided antibiotic discontinuation has shown to reduce the duration of antibiotic use, the associated adverse effects, and to decrease the overall mortality. The current review discusses the history and pathophysiology of procalcitonin, synthesizes its utility in the diagnosis and management of sepsis, highlights its limitations and compares it with other biomarkers in sepsis.

Diagnosis and treatment of acute pulmonary inflammation in critically ill patients: The role of inflammatory biomarkers

Pneumonia and acute respiratory distress syndrome are common and important causes of respiratory failure in the intensive care unit with a significant impact on morbidity, mortality and health care utilization despite early antimicrobial therapy and lung protective mechanical ventilation. Both clinical entities are characterized by acute pulmonary inflammation in response to direct or indirect lung injury. Adjunct anti-inflammatory treatment with corticosteroids is increasingly used, although the evidence for benefit is limited. The treatment decisions are based on radiographic, clinical and physiological variables without regards to inflammatory state. Current evidence suggests a role of biomarkers for the assessment of severity, and distinguishing sub-phenotypes (hyper-inflammatory versus hypo-inflammatory) with important prognostic and therapeutic implications. Although many inflammatory biomarkers have been studied the most common and of interest are C-reactive protein, procalcitonin, and pro-inflammatory cytokines including interleukin 6. While extensively studied as prognostic tools (prognostic enrichment), limited data are available for the role of biomarkers in determining appropriate initiation, timing and dosing of adjunct anti-inflammatory treatment (predictive enrichment).

Association between acute kidney injury and serum procalcitonin levels and their diagnostic usefulness in critically ill patients

Procalcitonin (PCT) is a useful marker for the diagnosis of systemic inflammatory response syndrome. In addition, PCT is affected by renal function. However, few studies have investigated the relationship between PCT and the development of acute kidney injury (AKI). Hence, we investigated whether serum PCT levels at the time of admission were associated with the development of AKI and clinical outcomes. A total of 790 patients in whom PCT was measured on admission to the intensive care unit (ICU) were analyzed retrospectively. We attempted to investigate whether serum PCT levels measured at the time of admission could be used as a risk factor for the development of AKI in septic and nonseptic patients or as a risk factor for all-cause mortality, and diagnostic usefulness of PCT was further assessed. Serum PCT levels were significantly higher in patients with AKI than in those without AKI (P < 0.001). After multivariable adjustment for clinical factors, laboratory findings, and comorbidities, PCT as a continuous variable showed a significant association with AKI (OR 1.006, 95% CI [1.000–1.011]; P = 0.035). However, PCT was not effective in predicting mortality. The cut-off value of PCT for the prediction of AKI incidence was calculated to be 0.315 ng/ml, with sensitivity and specificity of 60.9% and 56.9%, respectively. The odds ratios (ORs) from an equation adjusted for optimum thresholds of PCT levels for developing AKI with and without sepsis were 2.422 (1.222–4.802, P = 0.011) and 1.798 (1.101–2.937, P = 0.019), respectively. However, there were no absolute differences between the pre- and posttest probabilities after including the PCT value for AKI development. This study suggests that the PCT value was higher in AKI patients than in non-AKI patients, but PCT measurement at the time of admission did not improve the prediction model for AKI.

The effect of local anesthetic continuous wound infusion for the prevention of postoperative pneumonia after on-pump cardiac surgery with sternotomy: the STERNOCAT randomized clinical trial

PURPOSE

Postoperative pain after cardiac surgery, exacerbated by cough and sternal mobilization, limits clearance of bronchopulmonary secretions and may predispose to postoperative pneumonia. In this study, we tested the ability of local anesthetic continuous wound infusion to prevent pneumonia after cardiac surgery with sternotomy and cardiopulmonary bypass (CPB) owing to better analgesia and bronchopulmonary drainage.

METHODS

In this randomized, double-blind, placebo-controlled trial conducted in five academic centers, patients undergoing cardiac surgery with sternotomy and CPB were enrolled from February 2012 until November 2014, and were followed over 30 days. Patients were assigned to a 48-h infusion (10 ml h^-1) of L-bupivacaine (12.5 mg h^-1) or placebo (saline) via a pre-sternal multiperforated catheter. Anesthesia and analgesia protocols were standardized. The primary end point was the incidence of pneumonia during the study period, i.e., until hospital discharge or 30 days. We hypothesized a 30% reduction in the incidence of pneumonia.

RESULTS

Among 1493 randomized patients, 1439 completed the trial. Pneumonia occurred in 36/746 patients (4.9%) in the L-bupivacaine group and in 42/739 patients (5.7%) in the placebo group (absolute risk difference taking into account center and baseline risk of postoperative pneumonia, - 1.3% [95% CI - 3.4; 0.8] P = 0.22). In the predefined subgroup of patients at high risk, L-bupivacaine decreased the incidence of pneumonia (absolute risk difference, - 5.6% [95% CI - 10.0; - 1.1], P = 0.01).

CONCLUSIONS

After cardiac surgery with sternotomy, continuous wound infusion of L-bupivacaine failed to decrease the incidence of pneumonia. These findings do not support the use of local anesthetic continuous wound infusion in this indication. Further study should investigate its effect in high-risk patients.

TRIAL REGISTRATION

EudraCT Number: 2011-003292-10; Clinicaltrials.gov Identifier: NCT01648777.

Comparison of accuracy of presepsin and procalcitonin concentrations in diagnosing sepsis in patients with and without acute kidney injury

BACKGROUND

Levels of the biomarkers presepsin and procalcitonin are affected by renal function. We evaluated the accuracies of presepsin and procalcitonin levels for diagnosing sepsis in patients with and without acute kidney injury (AKI).

METHODS

We evaluated patients with presepsin and procalcitonin data, and classified them into AKI and non-AKI groups based on the Kidney Disease Improving Global Outcomes criteria. Each group was then subdivided according to sepsis status for each stage of AKI. Receiver operating characteristic curve analyses were used to investigate the accuracies of biomarker levels for diagnosing sepsis.

RESULTS

In the non-AKI group, the area under the curves (AUCs) for procalcitonin and presepsin levels were 0.897 and 0.880, respectively (p = .525) and optimal cut-off values were 0.10 ng/ml (sensitivity: 85.1%, specificity: 79.1%) and 240 pg/ml (sensitivity: 80.9%, specificity: 83.2%), respectively. In the stage 3 subgroup, the AUC for procalcitonin (0.946) was significantly higher than that for presepsin (0.768, p < .001). The optimal cut-off values for diagnosing sepsis were 4.07 ng/ml (sensitivity: 87.2%, specificity: 93.5%) for procalcitonin and 500 pg/ml (sensitivity: 89.7%, specificity: 59.7%) for presepsin.

CONCLUSIONS

In patients with severe AKI, the accuracy of the diagnosis of sepsis with procalcitonin was significantly higher than with presepsin.

High Serum Procalcitonin Concentrations in Patients With Hemorrhagic Fever With Renal Syndrome Caused by Hantaan Virus

Objective: This study analyzed the significance of procalcitonin (PCT) in patients with hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus.

Methods: The demographics and clinical and laboratory data including PCT at hospital admission in 146 adults with HFRS were retrospectively analyzed.

Results: PCT level was significantly higher in severe patients (n = 72) than in mild patients (n = 74, p < 0.001) and independently associated with disease severity (OR 2.544, 95% CI 1.330–4.868, p = 0.005). PCT had an area under the receiver operating characteristic curve (AUC) value of 0.738 (95% CI 0.657–0.820, p < 0.001) for predicting severity. PCT level was significantly increased in patients with bacterial infection (n = 87) compared with those without (n = 59, p = 0.037) and associated with bacterial infection (OR 1.685, 95% CI 1.026–2.768, p = 0.039). The AUC value of PCT for predicting bacterial infection was 0.618 (95% CI 0.524–0.711, p = 0.016). PCT level was significantly elevated in non-survivors (n = 13) compared with survivors (n = 133, p < 0.001) and independently associated with mortality (OR 1.075, 95% CI 1.003–1.152, p = 0.041). The AUC value of PCT for predicting mortality was 0.819 (95% CI 0.724–0.914, p < 0.001).

Conclusion: PCT concentrations at admission would be predictive of disease severity, secondary bacterial infection and mortality in patients with HFRS caused by Hantaan virus.

A Systematic Review and Meta-Analysis of Procalcitonin as a Marker of Postoperative Orthopedic Infections

Procalcitonin is a serologic marker that increases in response to inflammatory stimuli, especially those of bacterial origin. Postoperative orthopedic periprosthetic infections are often difficult to diagnose. This study systematically reviewed the literature to evaluate the statistical measures of performance of procalcitonin as a marker of postoperative orthopedic infection. This study showed that procalcitonin has a weighted pooled sensitivity of 67.3%, specificity of 69.4%, positive likelihood ratio of 1.778, negative likelihood ratio of 0.423, and diagnostic odds ratio of 5.770. These results illustrate that procalcitonin is an effective serologic marker for postoperative bacterial infections. [Orthopedics. 2018; 41(3):e303-e309.].

Summary of the international clinical guidelines for the management of hospital-acquired and ventilator-acquired pneumonia

A summary of the evidence and recommendations made in the ERS/ESICM/ESCMID/ALAT guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia http://ow.ly/S3zA30iZfLa.

Do we need new trials of procalcitonin-guided antibiotic therapy?

Using biomarkers as a guide to tailor the duration of antibiotic treatment in respiratory infections is an attractive hypothesis assessed in several studies. Recent work aiming to summarize the evidence assessed the effect of a procalcitonin (PCT)-guided antibiotic treatment on outcomes in acute lower respiratory tract infections (LRTI), suggesting that significant reductions in antibiotic duration occur when using a PCT-guided algorithm. However, controversial evidence also suggested PCT-guided algorithms were associated with increased antibiotic duration and increased incidence of Clostridium difficile, without any impact on mortality, in real-world settings. So, although using PCT-guided antibiotic stewardship is promising, after more than a decade of randomized controlled trials on this topic the evidence in its favor is still less than compelling due to limitations in trial design, not taking into consideration fundamental aspects of PCT biology, and the absence of evidence-based antimicrobial duration in intervention and control groups. In this commentary we highlight some questions and limitations of primary PCT study data that might impact interpretation and clinical use of PCT at the bedside.

Clinical value of procalcitonin for suspected nosocomial bloodstream infection

BACKGROUND/AIMS

Procalcitonin (PCT) may prove to be a useful marker to exclude or predict bloodstream infection (BSI). However, the ability of PCT levels to differentiate BSI from non-BSI episodes has not been evaluated in nosocomial BSI.

METHODS

We retrospectively reviewed the medical records of patients ≥ 18 years of age with suspected BSI that developed more than 48 hours after admission.

RESULTS

Of the 785 included patients, 105 (13.4%) had BSI episodes and 680 (86.6%) had non-BSI episodes. The median serum PCT level was elevated in patients with BSI as compared with those without BSI (0.65 ng/mL vs. 0.22 ng/mL, p = 0.001). The optimal PCT cut-off value of BSI was 0.27 ng/mL, with a corresponding sensitivity of 74.6% (95% confidence interval [CI], 66.4% to 81.7%) and a specificity of 56.5% (95% CI, 52.7% to 60.2%). The area under curve of PCT (0.692) was significantly larger than that of C-reactive protein (CRP; 0.526) or white blood cell (WBC) count (0.518). However, at the optimal cut-off value, PCT failed to predict BSI in 28 of 105 cases (26.7%). The PCT level was significantly higher in patients with an eGFR < 60 mL/min/1.73 m² than in those with an eGFR ≥ 60 mL/min/1.73 m² (0.68 vs. 0.17, p = 0.01).

CONCLUSIONS

PCT was more useful for predicting nosocomial BSI than CRP or WBC count. However, the diagnostic accuracy of predicting BSI remains inadequate. Thus, PCT is not recommended as a single diagnostic tool to avoid taking blood cultures in the nosocomial setting.

Biomarkers kinetics in the assessment of ventilator-associated pneumonia response to antibiotics - results from the BioVAP study

PURPOSE

Our aim was to evaluate the role of biomarker kinetics in the assessment of ventilator-associated pneumonia (VAP) response to antibiotics.

MATERIALS AND METHODS

We performed a prospective, multicenter, observational study to evaluate in 37 microbiologically documented VAP, the kinetics of C-reactive protein (CRP), procalcitonin (PCT), mid-region fragment of pro-adrenomedullin (MR-proADM). The kinetics of each variable, from day 1 to 6 of therapy, was assessed with a time dependent analysis comparing survivors and non-survivors.

RESULTS

During the study period kinetics of CRP as well as its relative changes, CRP-ratio, was significantly different between survivors and non-survivors (p=0.026 and p=0.005, respectively). On day 4 of antibiotic therapy, CRP of survivors was 47% of the initial value while it was 96% in non-survivors. The kinetics of other studied variables did not distinguish between survivors and non-survivors. In survivors the bacterial load also decreased markedly. Adequate initial antibiotic therapy was associated with lower mortality (p=0.025) and faster CRP decrease (p=0.029).

CONCLUSIONS

C-reactive protein kinetics can be used to identify VAP patients with poor outcome as soon as four days after the initiation of treatment. (Trial registration - NCT02078999; registered 3 August 2012).

The role of serum procalcitonin in establishing the diagnosis and prognosis of pleural infection

Background

Bacterial pleural infection requires prompt identification to enable appropriate investigation and treatment. In contrast to commonly used biomarkers such as C-reactive protein (CRP) and white cell count (WCC), which can be raised due to non-infective inflammatory processes, procalcitonin (PCT) has been proposed as a specific biomarker of bacterial infection. The utility of PCT in this role is yet to be validated in a large prospective trial. This study aimed to identify whether serum PCT is superior to CRP and WCC in establishing the diagnosis of bacterial pleural infection.

Methods

Consecutive patients presenting to a tertiary pleural service between 2008 and 2013 were recruited to a well-established pleural disease study. Consent was obtained to store pleural fluid and relevant clinical information. Serum CRP, WCC and PCT were measured. A diagnosis was agreed upon by two independent consultants after a minimum of 12 months. The study was performed and reported according to the STARD reporting guidelines.

Results

80/425 patients enrolled in the trial had a unilateral pleural effusion secondary to infection. 10/80 (12.5%) patients had positive pleural fluid microbiology. Investigations for viral causes of effusion were not performed. ROC curve analysis of 425 adult patients with unilateral undiagnosed pleural effusions showed no statistically significant difference in the diagnostic utility of PCT (AUC 0.77), WCC (AUC 0.77) or CRP (AUC 0.85) for the identification of bacterial pleural infection. Serum procalcitonin >0.085 μg/l has a sensitivity, specificity, negative predictive value and positive predictive value of 0.69, 0.80, 0.46 and 0.91 respectively for the identification of pleural infection. The diagnostic utility of procalcitonin was not affected by prior antibiotic use (p = 0.80).

Conclusions

The study presents evidence that serum procalcitonin is not superior to CRP and WCC for the diagnosis of bacterial pleural infection. The study suggests routine procalcitonin testing in all patients with unilateral pleural effusion is not beneficial however further investigation may identify specific patient subsets that may benefit.

Trial registration

The trial was registered with the UK Clinical Research Network (UKCRN ID 8960). The trial was approved by the South West Regional Ethics Committee (Ethical approval number 08/H0102/11).

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-017-0501-5) contains supplementary material, which is available to authorized users.

Diagnostic accuracy of procalcitonin and presepsin for infectious disease in patients with acute kidney injury

Procalcitonin (PCT) and presepsin (PSEP) are sepsis markers, but their diagnostic accuracy may be compromised in acute kidney injury (AKI). We evaluated their diagnostic accuracy in patients with/without AKI. This retrospective study comprised 91 patients with at least one criterion of systematic inflammatory response syndrome. AKI markers plasma neutrophil gelatinase-associated lipocalin (NGAL), plasma cystatin C (CysC), and estimated glomerular filtration rate (eGFR) were measured upon hospital admission and on days 1, 3, 5, and 7. Patients were divided into non-AKI and AKI groups. APACHE II severity scores were determined. PCT and PSEP levels were increased significantly in non-AKI and AKI patients with infection. NGAL, CysC, and eGFR in patients with infection were associated with PCT, PSEP, and APACHE II score, and levels of PCT and PSEP were correlated significantly with disease severity. PCT and PSEP are useful markers of bacterial infections in AKI but different thresholds should be applied.

Procalcitonin-guided antibiotic treatment in critically ill patients

PURPOSE

In critically ill patients, length of antibiotic treatment can be effectively guided by procalcitonin (PCT) protocols. International sepsis guidelines and guidelines on antibiotic stewardship strategies recommend PCT as helpful laboratory marker for a rational use of antibiotics. A number of studies and meta-analyses have confirmed the effectiveness of PCT-protocols for shortening antibiotic treatment without compromising clinical outcome in critically ill patients. But in clinical practice, there is still uncertainty how to interpret PCT levels and how to adjust antibiotic treatment in various infectious situations, especially in the perioperative period.

METHODS

This narrative review gives an overview on the application of PCT-protocols in critically ill patients with severe bacterial infections on the basis of 5 case reports and the available literature. Beside strengths and limitations of this biomarker, also varying kinetics and different maximum values with regard to the infectious focus and pathogens are discussed.

RESULTS

PCT-guided antibiotic treatment appears to be safe and effective. Most of the studies revealed a shorter antibiotic treatment without negative clinical outcomes. Cost effectiveness is still a matter of debate and effects on bacterial resistance due to shorter treatments, possible lower rates of drug-related adverse events, or decreased rates of Clostridium difficile infections are not yet evaluated.

CONCLUSION

Guidance of antibiotic treatment can effectively be supported by PCT-protocols. However, it is important to consider the limitations of this biomarker and to use PCT protocols along with antibiotic stewardship programmes and regular clinical rounds together with infectious diseases specialists.

Serum Procalcitonin as a Valuable Diagnostic Tool in the Early Detection of Infectious Complications after Open Abdominal Aortic Repair

BACKGROUND

Aortic aneurysm repair is a resolutive and effective surgical operation, which can be associated with severe postoperative complications. Procalcitonin (PCT) in clinical practice could play a role in early diagnosis and monitoring of therapy for complications, especially infections, making for timely and more effective interventions. Our aim was to investigate whether PCT could be a predictive marker in early diagnosis of infectious complications after open abdominal aortic surgery.

METHODS

Eighty-three consecutive patients who underwent elective open aortic repair at our institution were enrolled. Blood samples were taken before surgery, and each day over the 7-day postoperative period, and measurement of serum PCT, C-reactive protein (CRP), and leukocytes levels were carried out. Data regarding clinical progress, instrumental examinations, and blood chemistry were prospectively collected.

RESULTS

Postoperative infectious complications occurred in 24 patients. Within 30 days, 1 death occurred. In the study sample, we found a significant difference in PCT curves of patients with and without infectious complications, especially on third postoperative day (POD; P = 0.004). On analysis of the area under the curve (AUC curve), PCT was shown to be a fair predictor in distinguishing cases with infectious complications (AUC, 0.765 on third POD; CI, 0.638-0.877). Conversely, other inflammatory markers commonly used (leucocytes and CRP) had similar trends in patients with and without postoperative infections.

CONCLUSIONS

On the basis of the results collected in this pilot study, despite some limitations, PCT could be considered a better marker of infectious complications after open abdominal aortic repair, when compared with other routinely used parameters.

Tapered-cuff Endotracheal Tube Does Not Prevent Early Postoperative Pneumonia Compared with Spherical-cuff Endotracheal Tube after Major Vascular Surgery

Background

Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure.

Methods

This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency.

Results

Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P &lt; 0.001). Although microaspiration frequencies were high, they did not differ between groups.

Conclusion

For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.

Procalcitonin cannot be used as a biomarker of infection in heart surgery patients with acute kidney injury

PURPOSE

We intended to assess how acute kidney injuy impacts on procalcitonin levels in cardiac surgery patients, with or without infection, and whether procalcitonin might be used as a biomarker of infection in acute kidney injuy.

MATERIAL AND METHODS

A case-control study was designed which included patients that had had cardiac surgery between January 2011 and January 2015. Every patient developing severe sepsis or septic shock (n = 122; 5.5%) was enrolled. In addition, consecutive cardiac surgery patients during 2013 developing systemic inflammatory response syndrome (n = 318) were enrolled. Those recruited 440 patients were divided into 2 groups, according to renal function.

RESULTS

Median procalcitonin levels were significantly higher during the 10 postoperative days in the acute kidney injury patients. Regression analysis showed that postoperatory day, creatinine, white blood cells and infection were significantly (P < .0001) associated to serum procalcitonin level. In patients with creatinine ≥2, median procalcitonin levels were similar in infected and non-infected patients. Only when creatinine was less than 2 mg/L, the median procalcitonin levels were significantly higher in patients with infection, as compared to those with no infection.

CONCLUSIONS

In acute kidney injuy patients, high procalcitonin levels are a marker of acute kidney injuy but will not be able to differentiate infected from non-infected patients.

Recent advances in pathophysiology and biomarkers of sepsis-induced acute kidney injury

Sepsis is a complex clinical syndrome characterized by a systemic inflammatory response to an infective insult. This process often leads to widespread tissue injury and multiple organ dysfunction. In particular, the development of acute kidney injury (AKI) is one of the most frequent complications, which increases the complexity and cost of care, and is an independent risk factor for mortality. Previous suggestions highlighting systemic hypotension, renal vasoconstriction and ischaemia-reperfusion injury as the primary pathophysiological mechanisms involved in sepsis-induced AKI have been challenged. Recently it has been shown that sepsis-induced AKI occurs in the setting of microvascular dysfunction with release of microparticles, inflammation and energetic adaptation of highly metabolic organs to cellular stress. The intolerable high mortality rate associated with sepsis-induced AKI is partially explained by an incomplete understanding of its pathophysiology and a delay in diagnosis. The aim of this review is to focus on advances in understanding the sepsis pathophysiology, with particular attention to the fundamental mechanisms of sepsis-induced AKI and the potential diagnostic and prognostic markers involved.

Diagnosis and Treatment of Vascular Surgery Related Infection

Surgical site infection (SSI) is an important component of infections acquired from hospital. The most significant feature of vascular surgery different from other surgeries is frequent application of artificial grafts. Once SSI occurs after vascular operations with grafts, it might results in a serious disaster. Staphylococcus aureus and coagulase-negative Staphylococcus are the most common pathogenic bacteria for SSI after vascular surgery. Although SSI in vascular surgery often lacks of typical clinical characters, some clinical symptoms, laboratory data and certain imaging procedures may help to diagnose. In most cases of SSI after vascular procedures, the artificial grafts must be removed and sensitive antibiotics should be administered. However, for different cases, personalized management plan should be made depending on the severity and location of SSI.

Personalized treatment of severe pneumonia in cancer patients

Patients with cancer are at increased risk for sepsis as a consequence of immunosuppression. The hospital mortality remains elevated and it could be attributed to antibiotic failure because of the presence of multiresistant pathogens. Once the patient is critically ill, the use of the American Thoracic Society/Infectious Diseases Society of America classification does not seem very useful in the assessment of outcomes and the choice of antimicrobials. In critically ill patients, the characteristics of clinical response to antibiotics are usually inaccurate and occur late in the course of disease. So, the sequential evaluation of C-reactive protein-ratio is useful in the early identification of patients with antibiotic failure. To achieve safe and efficient antimicrobial therapy, we proposed an algorithm that may aid clinicians in their decision-making process.

Potential use of procalcitonin as biomarker for bacterial sepsis in patients with or without acute kidney injury

INTRODUCTION

There are few investigations regarding the relationships between procalcitonin (PCT) and the acute kidney injury (AKI) in the diagnosis of sepsis. The purpose of this study was to clarify the diagnostic accuracy of the use of PCT levels in patients with or without AKI.

METHODS

This study was conducted as a single-center retrospective study. We enrolled 393 patients in whom PCT were measured on admission. We grouped the patients into non-AKI and AKI, and those with AKI were classified according to the RIFLE criteria (Risk, Injury, Failure). The patients in each group were further classified into the sepsis and the non-sepsis group. We subsequently investigated the diagnostic accuracy of the PCT for detecting sepsis in these groups.

RESULTS

The levels of PCT were significantly higher in the sepsis group than in the non-sepsis group among the non-AKI and each AKI patients (p < 0.0001). The diagnostic accuracy of the PCT for detecting sepsis was determined according to a ROC analysis; AUC value was 0.958 in the non-AKI group, in the Risk, Injury and Failure groups were 0.888 and 0.917, 0.857, respectively. AUC value for non-AKI group was significantly different from that of Failure group (p < 0.05).

CONCLUSIONS

In Failure AKI patients, the diagnostic accuracy of the PCT level is significantly lower than non-AKI patients. It is therefore suggested that we should be careful in using PCT value to diagnose sepsis in patients with Failure under RIFLE criteria.

Clinical value of procalcitonin for patients with suspected bloodstream infection

OBJECTIVES

Procalcitonin (PCT) might be a useful marker to exclude bacteremia or to predict the severity of bacteremia and its outcome. However, most previous studies of PCT were limited to particular patient populations. In addition, reports about PCT levels in patients with renal dysfunction have been conflicting. We investigated the predictive value of PCT in an unselected population with suspected bloodstream infections and also assessed the relationship between PCT and renal function.

METHODS

We retrospectively analyzed medical records of 1,331 patients (age ≥1 8 years) with suspected bloodstream infections who had concurrent biochemical data and blood culture results.

RESULTS

The PCT level was significantly elevated in patients with positive blood cultures, and it showed a significant relation with survival in patients with bacteremia. The optimal cutoff value of PCT for predicting a positive blood culture showed an increase as the estimated glomerular filtration rate declined.

CONCLUSION

PCT can be a useful marker to exclude bacteremia and also to predict severe bacteremia, but renal function should be taken into account.

Procalcitonin in the recognition of complications in critically ill surgical patients

BACKGROUND

Procalcitonin (PCT) is a relatively new, promising indirect parameter for infection. In the intensive care unit (ICU) it can be used as a marker for sepsis. However, in the ICU there is a need for reliable markers for clinical deterioration in the critically ill patients. This study determines the clinical value of PCT concentrations in recognizing surgical complications in a heterogeneous group of general surgical patients in the ICU.

MATERIAL AND METHODS

We prospectively collected PCT concentration data from April 2010 to June 2012 for all general surgical patients admitted to the ICU. Both the relationships between PCT levels and events (diagnostic and therapeutic interventions) as well as between PCT levels and surgical complications (abscesses, bleeding, perforation, ischemia, and ileus) were studied.

RESULTS

PCT concentrations were lower in patients who developed complications than those who did not develop complications on the same day, although not significant (P = 0.27). A 10% increase in PCT levels resulted in a 2% higher complication odds, but again this was not significant (odds ratio [OR], 1.020; 95% confidence interval [CI], 0.961-1.083; P = 0.51). Even a 20% or 30% increase in PCT concentrations did not result in higher complication probability (OR, 1.039; 95% CI, 0.927-1.165 and OR, 1.057; 95% CI, 0.897-1.246). Furthermore, an increase in PCT levels did not show an increase or a reduction in the number of diagnostic and therapeutic interventions.

CONCLUSIONS

An increase in PCT levels does not help to predict surgical complications in critically ill surgical patients.

Use of expert panels to define the reference standard in diagnostic research: a systematic review of published methods and reporting

BACKGROUND

In diagnostic studies, a single and error-free test that can be used as the reference (gold) standard often does not exist. One solution is the use of panel diagnosis, i.e., a group of experts who assess the results from multiple tests to reach a final diagnosis in each patient. Although panel diagnosis, also known as consensus or expert diagnosis, is frequently used as the reference standard, guidance on preferred methodology is lacking. The aim of this study is to provide an overview of methods used in panel diagnoses and to provide initial guidance on the use and reporting of panel diagnosis as reference standard.

METHODS AND FINDINGS

PubMed was systematically searched for diagnostic studies applying a panel diagnosis as reference standard published up to May 31, 2012. We included diagnostic studies in which the final diagnosis was made by two or more persons based on results from multiple tests. General study characteristics and details of panel methodology were extracted. Eighty-one studies were included, of which most reported on psychiatry (37%) and cardiovascular (21%) diseases. Data extraction was hampered by incomplete reporting; one or more pieces of critical information about panel reference standard methodology was missing in 83% of studies. In most studies (75%), the panel consisted of three or fewer members. Panel members were blinded to the results of the index test results in 31% of studies. Reproducibility of the decision process was assessed in 17 (21%) studies. Reported details on panel constitution, information for diagnosis and methods of decision making varied considerably between studies.

CONCLUSIONS

Methods of panel diagnosis varied substantially across studies and many aspects of the procedure were either unclear or not reported. On the basis of our review, we identified areas for improvement and developed a checklist and flow chart for initial guidance for researchers conducting and reporting of studies involving panel diagnosis. Please see later in the article for the Editors' Summary.

Elevated procalcitonin is associated with increased mortality in patients with scrub typhus infection needing intensive care admission

Context:

Procalcitonin is a biomarker of bacterial sepsis. It is unclear if scrub typhus, a rickettsial illness, is associated with elevated procalcitonin levels.

Aim:

To assess if scrub typhus infection is associated with high procalcitonin levels and whether high levels portend a poorer prognosis.

Setting and Design:

Retrospective study of patients with severe scrub typhus infection, admitted to the medical intensive care unit of a tertiary care university affiliated teaching hospital.

Materials and Methods:

Eighty-four patients with severe scrub typhus infection that also had procalcitonin levels were assessed.

Statistical Analysis:

Relationship between procalcitonin and mortality explored using univariate and multivariate analyses.

Results:

The mean (±standard deviation) age was 40.0 ± 15.5 years. Patients were symptomatic for 8.3 ± 4.3 days prior to presentation. The median admission procalcitonin level was 4.0 (interquartile range 1.8 to 8.5) ng/ml; 59 (70.2%) patients had levels >2 ng/ml. Invasive mechanical ventilation was required in 65 patients; 20 patients died. On univariate analysis, admission procalcitonin was associated with increased odds of death [odds ratio (OR) 1.09, 95% confidence interval (CI) 1.03 to 1.18]. On multivariate logistic regression analysis including procalcitonin and APACHE-II score, the APACHE-II score was significantly associated with mortality (OR 1.16, 95% CI 1.06 to 1.30, P = 0.004) while a trend was observed with procalcitonin (OR 1.05, 95%CI 1.01 to 1.13, P = 0.09). The area under the receiver operating characteristic (ROC) curve, AUC, for mortality was 0.77 for procalcitonin and 0.78 for APACHE-II.

Conclusions:

Procalcitonin is elevated in severe scrub typhus infection and may be associated with higher mortality.