Procalcitonin as a biomarker of infectious diseases

The Role of Hematologic Markers, Procalcitonin and Neopterin in Inflammatory Response in Cattle With Theileria annulata

The disease named tropical theileriosis is caused by the protozoan pathogen Theileria annulata (T. annulata) transmitted through Hyalomma species ticks. The current study has been designed to determine the haematological, inflammatory and oxidative stress status in cattle naturally infected with T. annulata. The study consisted of two groups: a control group (10 cattle) and a theileriosis group (10 cattle). Compared to the control group, the animals in the theileriosis group exhibited a significant decrease in erythrocyte count, haemoglobin count, haematocrit levels and mean corpuscular haemoglobin concentration, while a notable increase in mean corpuscular volume was observed (p < 0.001; p < 0.01; p < 0.01; p < 0.05; p < 0.05, respectively). However, no significant differences were found between the groups for the other haematological indices (p > 0.05). In terms of oxidative stress markers, the theileriosis group exhibited higher malondialdehyde (MDA) (p < 0.001) and significantly lower superoxide dismutase (SOD) (p < 0.001) levels compared to the control group. No significant difference was observed between the groups in terms of catalase (CAT) levels. Compared to the control group, haptoglobin (Hp) (p < 0.001) and procalcitonin (PCT) (p < 0.001) levels were significantly higher in the theileriosis group, while no significant difference was observed in neopterin levels between the two groups (p > 0.05). In conclusion, significant differences were identified in haematological indices, acute phase response, inflammatory marker levels, and oxidative stress marker levels in theileriosis. Additionally, Hp and PCT levels may be crucial in determining the inflammatory status.

Clinical Diagnosis of Acute Noma: Essential Infection Markers and Clinical Presentations

In clinical settings, understanding the markers and clinical signs of infection is critical for timely diagnosis and treatment. However, a point-of-care diagnostic test is lacking for noma, a debilitating orofacial infectious disease. This retrospective study reviewed electronic medical records (EMRs) and paper medical records (PMRs) of noma patients from Facing Africa (235 EMRs), Yekatit 12 Hospital (68 PMRs), and Project Harar (33 PMRs) in Ethiopia to identify essential infection markers and clinical presentations of acute noma. The review identified seven acute noma patients aged 4-9 years. The patients presented with facial edema, pain, anorexia, ecchymosis, excessive salivation, and drooling, as well as specific symptoms such as visual disturbances, high fever, foul odor, halitosis, and local tenderness. Laboratory findings included elevated white blood cell counts (13,500-14,500 cells/mcL), C-reactive protein levels (107-148 mg/L), and erythrocyte sedimentation rates (65-90 mm/hour). At >85 ng/mL, procalcitonin levels were particularly high. Accurate diagnosis of noma requires a comprehensive approach that includes thorough clinical examination, appropriate disease stage classification, medical history review, and laboratory testing. The study highlights the critical infection markers and clinical presentations associated with acute noma that may aid in early diagnosis of the disease. Further research with a much larger number of participants is needed. However, given the difficulty in identifying acute noma cases due to the rapid progression and very high mortality of the disease and the challenge of accessing acute noma cases owing to various socioeconomic barriers, the results of this small study are still relevant.

CD177, MYBL2, and RRM2 Are Potential Biomarkers for Musculoskeletal Infections

BACKGROUND

Biomarkers of infection are measurable indicators that reflect the presence of an infection in the body. They are particularly valuable for detecting infections and tracking treatment responses. Previous transcriptome analysis of peripheral blood mononuclear cells (PBMCs) collected from patients during the active phase of diabetic foot infection identified the upregulation of several genes, including a neutrophil-specific cell surface glycoprotein, CD177, an Myb-related transcription factor 2 (MYBL2), and ribonucleotide reductase regulatory subunit M2 (RRM2). We aimed to investigate whether these observations in diabetic foot infections could be extrapolated to other musculoskeletal infections.

QUESTIONS/PURPOSES

(1) Are the protein concentrations of CD177, MYBL2, and RRM2 elevated in serum or PBMCs of patients with musculoskeletal infections? (2) Do serum and PBMC concentrations of CD177, MYBL2, and RRM2 decrease in response to antibiotic therapy? (3) Can these biomarkers give diagnostic accuracy and differentiate patients with musculoskeletal infections from controls?

METHODS

From April 2023 to June 2024, we treated 26 patients presenting with clinical symptoms and signs of acute musculoskeletal infections, including elevated inflammatory markers (white blood cell [WBC] and C-reactive protein [CRP]) and local changes such as swelling, erythema, tenderness or pain, warmth, purulent drainage, sinus tract, or wound leading to bone or hardware. Diagnosis included periprosthetic joint infection (PJI), foot and ankle infection (FAI), fracture-related infection (FRI), and septic arthritis of the native joints. Patients with chronic recurrent osteomyelitis, PJI, or FRI were excluded from the study. Among the 26 patients deemed potentially eligible, 19% (5) were excluded for the following reasons: prison inmate (1), unable to provide consent because of severe sepsis (1), mental illness (1), and declined to participate (2). Of the 81% (21) of patients who provided consent, cultures from 9.5% (2) were negative. These two patients were ultimately diagnosed with inflammatory arthritis: gout (1) and rheumatoid arthritis (1); thus, the musculoskeletal infection group for analysis consisted of 73.1% (19 of 26) of patients. A control group of 21 patients undergoing elective foot or ankle deformity correction surgery without infections or systemic inflammation was included. Because foot or ankle deformity is highly unlikely to influence the immunologic profile of the subjects, we believed that these patients would serve as an appropriate control group. Other than the absence of infection and the lower prevalence of diabetes mellitus, the control group was comparable to the study group in terms of demographics and clinical factors, including age and sex distribution. We collected blood samples from both patients and controls and quantified CD177, MYBL2, and RRM2 RNA transcription levels in the PBMC using qRT-PCR. We also assessed protein concentrations in the serum and PBMC using an enzyme-linked immunosorbent assay. A comparative analysis of the three biomarkers was performed on 19 patients with musculoskeletal infections with positive cultures and 21 controls to assess their diagnostic potential using the unpaired nonparametric t-test with the Mann-Whitney test. We obtained 8-week follow-up blood samples from seven patients with musculoskeletal infections who clinically healed. Healing was defined by normalization of inflammatory markers (WBC and CRP) and absence of swelling, erythema, local tenderness or pain, warmth, purulent drainage, sinus tract, or open wound. We performed a comparative analysis of the seven patients during active infection and after treatment to determine a change in the level of CD177, MYBL2, and RRM2 in their serum and PBMCs. These findings were also compared with those of the control group. We evaluated the diagnostic accuracy of CD177, MYBL2, and RRM2 for musculoskeletal infections using receiver operating characteristic (ROC) curve analysis.

RESULTS

The musculoskeletal infections group showed a larger increased serum and PBMC concentrations of CD177, MYBL2, and RRM2 proteins compared with the control group. The mean protein concentrations of CD177, MYBL2, and RRM2 were increased in the serum and PBMC of the musculoskeletal infections group compared with the controls. Serum levels of all biomarkers investigated were higher in musculoskeletal infections group compared with the control group (CD177 227 [155 to 432] versus 54 [10 to 100], difference of medians 173, p < 0.01; MYBL2 255 [231 to 314] versus 180 [148 to 214], difference of medians 75, p < 0.01; RRM2 250 [216 to 305] versus 190 [148 to 255], difference of medians 60, p < 0.01). Similarly, PBMC levels of all biomarkers were higher in the musculoskeletal infections group (CD177 55.3 [39.1 to 80.5] versus 17.5 [10.5 to 27.5], difference of medians 37.8, p < 0.01; MYBL2 144 [114 to 190] versus 91 [70 to 105], difference of medians 53, p < 0.01; RRM2 168 [143 to 202] versus 100 [77.5 to 133], difference of medians 68, p < 0.01). Additionally, serum levels of all biomarkers decreased in seven patients with musculoskeletal infections after infection treatment (CD177 3080 [2690 to 3320] versus 4250 [3100 to 8640], difference of medians 1170, p < 0.01; MYBL2 4340 [4120 to 4750] versus 5010 [4460 to 5880], difference of medians 670, p < 0.01; RRM2 4350 [3980 to 5000] versus 5025 [4430 to 6280], difference of medians 675, p = 0.01). Similarly, PBMC levels of all biomarkers were lower after infection treatment (CD177 805 [680 to 980] versus 1025 [750 to 1610], difference of medians 220, p < 0.01; MYBL2 2300 [2100 to 2550] versus 2680 [2220 to 3400], difference of medians 380, p = 0.02; RRM2 2720 [2500 to 3200] versus 3350 [2825 to 4030], difference of medians 630, p < 0.01). The area under the ROC curve for diagnosing musculoskeletal infections in the serum and PBMC was as follows: CD177 95% confidence interval [CI] > 0.99 and > 0.99, MYBL2 95% CI > 0.99 and > 0.99, and RRM2 95% CI = 0.96 and > 0.99, respectively.

CONCLUSION

We may utilize blood-based tests for CD177, MYBL2, and RRM2 to aid in the diagnosis of musculoskeletal infections, particularly when arthrocentesis or obtaining tissue culture is challenging. They may also assist in monitoring treatment response. As some of these biomarkers may also be elevated in other inflammatory conditions, a large-scale clinical study is needed to confirm their reliability in differentiating musculoskeletal infections from other inflammatory conditions.

CLINICAL RELEVANCE

CD177, MYBL2, and RRM2 proteins in blood samples may serve as novel biomarkers for diagnosing and monitoring treatment response in musculoskeletal infections.

Paper-Based procalcitonin and Interleukin-6 test strip with Spectrum-Based optical reader for enterovirus severity differentiation in children

Infectious diseases significantly impact global health, necessitating prompt diagnosis to mitigate life-threatening sepsis risk. Identifying patients at risk of severe neurological complications from enterovirus infections is challenging due to nonspecific initial presentations. Point-of-care testing (POCT) has emerged as a transformative tool, with low-cost lateral-flow colorimetric assays showing promise in deployable POCT devices. We developed a PCT/IL-6 rapid diagnostic system integrating lateral flow assay (LFA) test strips and a portable optical spectrum reader, allowing simultaneous semi-quantitative measurement of serum PCT and IL-6 within 30 min at the point of care. The system demonstrated a strong correlation with traditional ELISA and effectively differentiated severe pediatric enterovirus cases using serum samples. IL-6 showed superior discriminatory ability over PCT in identifying patients with severe neurological complications. This novel diagnostic platform holds great potential for early sepsis recognition and infectious disease management, especially in resource-limited settings.

Infective Complications of Endobronchial Ultrasound-Transbronchial Needle Aspiration (EBUS-TBNA) and Clinical Biomarkers: A Concise Review

EBUS-TBNA is the most common interventional pulmonology procedure performed globally and remains the cornerstone of the diagnosis and staging not only of lung cancer but also for other neoplastic, inflammatory, and infective pathologies of the mediastinum. Infective complications of EBUS-TBNA are underreported in the literature, but the constantly rising incidence of lung cancer is leading to an increasing number of EBUS-TBNA procedures and, therefore, to a significant number of infective complications, even 4 weeks following the procedure. In this review we attempt to summarize the risk factors related to these infective complications, along with useful biomarkers that can be used to identify patients that might develop infective complications, to facilitate the prediction or even prompt treatment of these.

Correlation Between Systemic Inflammation, Gut Microbiome Dysbiosis and Postoperative Complications After the Modified Whipple Procedure

(1) Background: The modified Whipple procedure, or pylorus-preserving pancreaticoduodenectomy, is a complex surgical intervention used to treat pancreatic head tumors. While preserving digestive function, it is associated with significant perioperative risks. This study explores the clinical, immunological, and microbiome-related factors influencing postoperative complications, focusing on the interplay between patient comorbidities, systemic inflammation, and gut dysbiosis. (2) Methods: A retrospective analysis was conducted on 123 patients undergoing the modified Whipple procedure for pancreatic head tumors. Patients were categorized into two groups based on the occurrence of significant postoperative complications (Group A: with complications; Group B: without complications). Data on demographics, comorbidities, inflammatory markers (CRP, IL-6, procalcitonin), and gut microbiome composition were collected. Microbial diversity was evaluated using the Shannon Index, and logistic regression was performed to identify independent predictors of complications. (3) Results: Patients in Group A had a significantly higher prevalence of diabetes mellitus (43.1% vs. 20.8%; p = 0.02) and cardiovascular disease (35.3% vs. 13.9%; p = 0.01). Elevated inflammatory markers (CRP ≥ 40 mg/L, IL-6 ≥ 30 pg/mL, procalcitonin ≥ 0.5 ng/mL) were strongly associated with higher complication rates. Microbiome analysis indicated dysbiosis in Group A, with reduced Lactobacillus and Bifidobacterium levels, increased Enterobacteriaceae abundance, and a lower Shannon Index (<2). Patients exhibiting both dysbiosis and elevated inflammation had the highest complication rate (60%). Multivariate analysis identified diabetes, elevated IL-6, and dysbiosis as independent predictors of adverse outcomes. (4) Conclusions: Postoperative complications after the modified Whipple procedure are influenced by systemic inflammation and gut dysbiosis. A systematic preoperative assessment of microbiome health and inflammatory markers enables accurate risk stratification and personalized interventions, potentially reducing the incidence of complications and improving overall surgical outcomes.

Can we predict bleeding at admission in Crimean-Congo hemorrhagic fever?

BACKGROUND

In Crimean-Congo hemorrhagic fever, bleeding has a significant impact on the prognosis of the disease. In our study, we aimed to identify independent risk factors for the development of bleeding in Crimean-Congo hemorrhagic fever and to contribute to the management of the disease.

METHODS

Cases with a definitive diagnosis of Crimean-Congo hemorrhagic fever were divided into two groups: those who developed bleeding and those who did not. Demographic, clinical and laboratory parameters were subjected to logistic regression analysis in terms of risk factors for bleeding development. Cut-off values for numerical variables were determined by receiver operating characteristics.

RESULTS

A total of 74 patients diagnosed with CCHF were included in the study. Bleeding occurred in at least one defined focus in 21 patients. In the multivariate logistic regression model, procalcitonin, days from symptom onset to admission, platelet count, and d-dimer were identified as independent risk factors for bleeding development. Procalcitonin had the most significant effect, with an approximately 5.3-fold increase in bleeding risk for each unit increase in its level. For discriminate bleeding, LDH and ferritin exhibited the highest sensitivity, while procalcitonin showed the highest specificity.

CONCLUSION

This study demonstrates the potential use of specific clinical and laboratory variables to predict bleeding development in CCHF patients. Procalcitonin elevation and the time from symptom onset to hospital admission have a significant effect in predicting bleeding.

A Rapid Host Response Blood Test for Bacterial/Viral Infection Discrimination Using a Portable Molecular Diagnostic Platform

Background

Difficulty discriminating bacterial versus viral etiologies of infection drives unwarranted antibacterial prescriptions and, therefore, antibacterial resistance.

Methods

Utilizing a rapid portable test that measures peripheral blood host gene expression to discriminate bacterial and viral etiologies of infection (the HR-B/V assay on Biomeme's polymerase chain reaction-based Franklin platform), we tested 3 cohorts of subjects with suspected infection: the HR-B/V training cohort, the HR-B/V technical correlation cohort, and a coronavirus disease 2019 cohort.

Results

The Biomeme HR-B/V test showed very good performance at discriminating bacterial and viral infections, with a bacterial model accuracy of 84.5% (95% confidence interval [CI], 80.8%-87.5%), positive percent agreement (PPA) of 88.5% (95% CI, 81.3%-93.2%), negative percent agreement (NPA) of 83.1% (95% CI, 78.7%-86.7%), positive predictive value of 64.1% (95% CI, 56.3%-71.2%), and negative predictive value of 95.5% (95% CI, 92.4%-97.3%). The test showed excellent agreement with a previously developed BioFire HR-B/V test, with 100% (95% CI, 85.7%-100.0%) PPA and 94.9% (95% CI, 86.1%-98.3%) NPA for bacterial infection, and 100% (95% CI, 93.9%-100.0%) PPA and 100% (95% CI, 85.7%-100.0%) NPA for viral infection. Among subjects with acute severe acute respiratory syndrome coronavirus 2 infection of ≤7 days, accuracy was 93.3% (95% CI, 78.7%-98.2%) for 30 outpatients and 75.9% (95% CI, 57.9%-87.8%) for 29 inpatients.

Conclusions

The Biomeme HR-B/V test is a rapid, portable test with high performance at identifying patients unlikely to have bacterial infection, offering a promising antibiotic stewardship strategy that could be deployed as a portable, laboratory-based test.

Hospital Variations and Temporal Trends in Procalcitonin Use for Patients With Bronchiolitis

BACKGROUND AND OBJECTIVE

The financial burden of bronchiolitis-related hospitalizations in the United States surpasses $700 million annually. Procalcitonin (PCT) has garnered recent interest in pediatrics and has demonstrated the potential to decrease antibiotic usage in other illnesses. This study assessed PCT utilization trends in bronchiolitis, hypothesizing an annual increase in PCT testing.

METHODS

We conducted a multicenter, retrospective cross-sectional study utilizing the Pediatric Health Information Systems database. Infants aged 2 to 23 months presenting with bronchiolitis from January 1, 2016, to December 31, 2022, were included. Encounters with and without PCT testing were compared using χ2 testing and Wilcoxon rank-sum testing as appropriate. Temporal trends in PCT testing and correlations with hospital-level proportions of PCT use, antibiotic administration, and admission proportion were assessed using Spearman's ρ.

RESULTS

There were 366 643 bronchiolitis encounters among 307 949 distinct patients across 38 hospitals during the study period. Of those, 1.5% (5517 of 366 643) had PCT testing performed. PCT usage increased more than 14-fold between 2016 and 2022 (0.2% in 2016 vs 2.8% in 2022, ρ > 0.99, P < .001). PCT use ranged from 0.01% to 8.29% across hospitals. The hospital-level proportion of PCT testing was not associated with admissions (ρ = 0.13, P = .42) or antibiotic use (ρ = 0.31, P = .06).

CONCLUSIONS

PCT testing in patients with bronchiolitis increased 14-fold between 2016 and 2022 and was not associated with decreased antimicrobial prescriptions. Further studies are needed to determine the diagnostic yield of PCT in bronchiolitis.

Implementing antimicrobial stewardship: lessons and perspectives from a university-affiliated tertiary hospital in Korea

Antimicrobial stewardship programs (ASPs) can lower antibiotic use, decrease medical expenses, prevent the emergence of resistant bacteria, and enhance treatment for infectious diseases. This study summarizes the stepwise implementation and effects of ASPs in a single university-affiliated tertiary care hospital in Korea; it also presents future directions and challenges in resource-limited settings. At the study hospital, the core elements of the ASP such as leadership commitment, accountability, and operating system were established in 2000, then strengthened by the formation of the Antimicrobial Stewardship (AMS) Team in 2018. The actions of ASPs entail key components including a computerized restrictive antibiotic prescription system, prospective audit, post-prescription review through quantitative and qualitative intervention, and pharmacy-based interventions to optimize antibiotic usage. The AMS Team regularly tracked antibiotic use, the effects of interventions, and the resistance patterns of pathogens in the hospital. The reporting system was enhanced and standardized by participation in the Korea National Antimicrobial Use Analysis System, and educational efforts are ongoing. Stepwise implementation of the ASP and the efforts of the AMS Team have led to a substantial reduction in the overall consumption of antibiotics, particularly regarding injectables, and optimization of antibiotic use. Our experience highlights the importance of leadership, accountability, institution-specific interventions, and the AMS Team.

Kinetics of Different Blood Biomarkers during Polymyxin-B Extracorporeal Hemoperfusion in Abdominal Sepsis

INTRODUCTION

Comparison of the marker kinetics procalcitonin, presepsin, and endotoxin during extracorporeal hemoperfusion with polymyxin-B adsorbing cartridge (PMX-HA) has never been described in abdominal sepsis. We aimed to compare the trend of three biomarkers in septic post-surgical abdominal patients in intensive care unit (ICU) treated with PMX-HA and their prognostic value.

METHODS

Ninety abdominal post-surgical patients were enrolled into different groups according to the evidence of postoperative sepsis or not. Non-septic patients admitted in the surgical ward were included in C group (control group). ICU septic shock patients with endotoxin levels <0.6 EAA receiving conventional therapy were addressed in S group and those with endotoxin levels ≥0.6 EAA receiving treatment with PMX-HA, besides conventional therapy, were included in SPB group. Presepsin, procalcitonin, endotoxin and other clinical data were recorded at 24 h (T0), 72 h (T1) and 7 days (T2) after surgery. Clinical follow-up was performed on day 30.

RESULTS

SPB group showed reduced levels of the three biomarkers on T2 versus T0 (p < 0.001); presepsin, procalcitonin and endotoxin levels decreased, respectively, by 25%, 11%, and 2% on T1 versus T0, and 40%, 41%, and 26% on T2 versus T0. All patients in C group, 73% of patients in SPB group versus 37% of patients in S group survived at follow-up. Moreover, procalcitonin had the highest predictive value for mortality at 30 days, followed by presepsin.

CONCLUSION

The present study showed the reliability of presepsin in monitoring PMX-HA treatment in septic shock patients. Procalcitonin showed better predicting power for the mortality riSsk.

Plasma levels of neurogenic inflammation related neuropeptides in pediatric patients with community-acquired pneumonia and their potential diagnostic value in distinguishing viral and bacterial pneumonia

Neurogenic inflammation is involved in the development and progression of respiratory inflammatory diseases. However, its role in community-acquired pneumonia (CAP) remains unclear. We therefore aimed to investigate plasma levels of neurogenic inflammation-related neuropeptides, calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY), and procalcitonin (PCT) in pediatric patients with CAP and to assess their diagnostic value in viral and bacterial/mixed pneumonia. A total of 124 pediatric patients with CAP (1 month-18 years old) and 56 healthy children of similar ages were prospectively enrolled. The patients were classified as viral (n = 99) and bacterial/mixed (n = 25) pneumonia. Plasma levels of the peptides were quantified by ELISA. ROC analysis was performed to evaluate possible diagnostic value of the peptides. While plasma levels of CGRP, VIP and PCT were significantly higher in patients with CAP than in the control group, respectively, NPY levels were significantly lower. Moreover, plasma levels of all neuropeptides and PCT were significantly higher in bacterial pneumonia patients compared to viral pneumonia patients. ROC analysis revealed that CGRP, SP and NPY had a diagnostic value in distinguishing viral and bacterial/mixed pneumonia.

CONCLUSIONS

Our findings suggest that these neuropeptides may be implicated in pediatric CAP. CGRP, SP and NPY together may be a promising candidate in distinguishing viral and bacterial/mixed pneumonia, however, for this, further studies are needed.

WHAT IS KNOWN

• Neurogenic inflammation contributes to the development and progression of respiratory inflammatory diseases such as chronic obstructive pulmonary disease and bronchial asthma.

WHAT IS NEW

• Plasma levels of neurogenic inflammation related neuropeptides calcitonin gene-related peptide, substance P, vasoactive intestinal peptide and neuropeptide Y are changed in pediatric community-acquired pneumonia. Calcitonin gene-related peptide, substance P and neuropeptide Y are promising candidates in distinguishing viral and bacterial/mixed pneumonia.

Persistently High Procalcitonin and C-Reactive Protein Are Good Predictors of Infection in Acute Necrotizing Pancreatitis: A Systematic Review and Meta-Analysis

Infected necrotizing pancreatitis (INP) is associated with an increased risk of organ failure and mortality. Its early recognition and timely initiation of antibiotic therapy can save patients' lives. We systematically searched three databases on 27 October 2022. In the eligible studies, the presence of infection in necrotizing pancreatitis was confirmed via a reference test, which involved either the identification of gas within the necrotic collection through computed tomography imaging or the examination of collected samples, which yielded positive results in Gram staining or culture. Laboratory biomarkers compared between sterile necrotizing pancreatitis and INP were used as the index test, and our outcome measures included sensitivity, specificity, the receiver operating characteristic (ROC) curve and area under the ROC curve (AUC). Within the first 72 hours (h) after admission, the AUC of C-reactive protein (CRP) was 0.69 (confidence interval (CI): 0.62-0.76), for procalcitonin (PCT), it was 0.69 (CI: 0.60-0.78), and for white blood cell count, it was 0.61 (CI: 0.47-0.75). After the first 72 h, the pooled AUC of CRP showed an elevated level of 0.88 (CI: 0.75-1.00), and for PCT, it was 0.86 (CI: 0.60-1.11). The predictive value of CRP and PCT for infection is poor within 72 h after hospital admission but seems good after the first 72 h. Based on these results, infection is likely in case of persistently high CRP and PCT, and antibiotic initiation may be recommended.

Pregnancy Outcomes in Patients with Urosepsis and Uncomplicated Urinary Tract Infections-A Retrospective Study

Background and Objectives: Urinary tract infections (UTIs) are an important cause of perinatal and maternal morbidity and mortality. The aim of this study was to describe and compare the main pregnancy outcomes among pregnant patients with complicated and uncomplicated UTIs; Materials and Methods: This retrospective study included 183 pregnant patients who were evaluated for uncomplicated UTIs and urosepsis in the Urology Department of 'C.I. Parhon' University Hospital, and who were followed up at a tertiary maternity hospital-'Cuza-voda' from Romania between January 2014 and October 2023. The control group (183 patients) was randomly selected from the patient's cohort who gave birth in the same time frame at the maternity hospital without urinary pathology. Clinical and paraclinical data were examined. Descriptive statistics and a conditional logistic regression model were used to analyze our data. Results: Our results indicated that patients with urosepsis had increased risk of premature rupture of membranes (aOR: 5.59, 95%CI: 2.02-15.40, p < 0.001) and preterm birth (aOR: 2.47, 95%CI: 1.15-5.33, p = 0.02). We could not demonstrate a statistically significant association between intrauterine growth restriction and pre-eclampsia with the studied urological pathologies. Conclusions: Careful UTI screening during pregnancy is needed for preventing maternal-fetal complications.

Extracellular vesicles in bacterial and fungal diseases - Pathogenesis to diagnostic biomarkers

Intercellular communication among microbes plays an important role in disease exacerbation. Recent advances have described small vesicles, termed as "extracellular vesicles" (EVs), previously disregarded as "cellular dust" to be vital in the intracellular and intercellular communication in host-microbe interactions. These signals have been known to initiate host damage and transfer of a variety of cargo including proteins, lipid particles, DNA, mRNA, and miRNAs. Microbial EVs, referred to generally as "membrane vesicles" (MVs), play a key role in disease exacerbation suggesting their importance in pathogenicity. Host EVs help coordinate antimicrobial responses and prime the immune cells for pathogen attack. Hence EVs with their central role in microbe-host communication, may serve as important diagnostic biomarkers of microbial pathogenesis. In this review, we summarize current research regarding the roles of EVs as markers of microbial pathogenesis with specific focus on their interaction with host immune defence and their potential as diagnostic biomarkers in disease conditions.

Comparative Characterization of Procalcitonin (Sensitivity, Specificity, Predictability, and Cut-Off Reference Values) as a Marker of Inflammation in Odontogenic Abscesses of the Head and Neck in the Female Population

Introduction Odontogenic abscesses of the head and neck can lead to serious complications and even end in death. This requires healthcare professionals to have a good knowledge of all the markers of inflammation that can be used in their diagnosis and treatment. Such markers that we use in our daily medical practice are leukocytes (WBC), neutrophils (Neu), and C-reactive protein (CRP). Somehow, in the background is procalcitonin (PCT), which has not been studied in detail in this type of purulent infection. The aim of the present study is to investigate and analyze PCT in odontogenic purulent infections of the head and neck in the female population and to compare it with already proven markers of inflammation such as CRP, WBC, and Neu. For the first time in the literature, as per our knowledge, the sensitivity, specificity, and predictability of PCT were determined when using it as an independent indicator of inflammation, and its cut-off reference values were determined in women with odontogenic abscesses of the head and neck. Materials and methods This is a prospective study, in which the CRP, WBC, Neu, and PCT of 30 women with odontogenic abscesses of the head and neck with a mean age of 47 (18-81) years were examined and analyzed. As a control group, we included 30 healthy women with a mean age of 48 (18-80) years, in whom there was no anamnestic and physical evidence of the presence of any infection in the last three months. The four markers were measured for the control group too. Results In the clinical group of women with odontogenic abscesses of the head and neck, the average values of CRP, WBC, Neu, and PCT were significantly higher (p<0.0001) compared to the same in the control group of healthy women; CRP: 95.46±76.41 mg/l vs. 0.63±0.37 mg/l, WBC: 10.44±2.97x103/L vs. 6.5±1.49x103/L, Neu: 7.92±2.93x103/L vs. 4.03±1.07x103/L, PCT: 0.74±0.69 ng/ml vs. 0.14±0.08 ng/ml. Discussion PCT, as well as CRP, WBC, and Neu, increases its plasma concentration in women with odontogenic abscesses of the head and neck and is extremely well positively correlated with them, with a high correlation with CRP and a significant correlation with WBC and Neu. In addition, PCT has a number of advantages over the other markers; it begins to increase its plasma concentration faster, reaches its maximum plasma concentration faster, normalizes its concentration faster after the infection subsides, and increases its blood level only in bacterial infection genesis. Conclusions PCT as a marker of inflammation not only positively correlates well with CRP, WBC, and Neu but also, with its advantages over them, it appears to be the most accurate indicator in the diagnosis, treatment, and follow-up of odontogenic head and neck abscesses in the near future; not only in women but also in the male and children's population. Its sensitivity, specificity, and predictability as an independent indicator of inflammation are 80%, 76.7%, and 83%, respectively, and its cut-off value of 0.225 ng/ml is lower than the generally accepted 0.5 ng/ml.

Severe and fatal COVID-19 is characterised by increased circulating glucagon like peptide 1 and procalcitonin modulated by type 2 diabetes

AIMS

Endotoxemia commonly occurs in severe and fatal COVID-19, suggesting that concomitant bacterial stimuli may amplify the innate immune response induced by SARS-CoV-2. We previously demonstrated that the endogenous glucagon like peptide 1 (GLP-1) system in conjunction with increased procalcitonin (PCT) is hyperactivated in patients with severe Gram-negative sepsis and modulated by type 2 diabetes (T2D). We aimed to determine the association of COVID-19 severity with endogenous GLP-1 activation upregulated by increased specific pro-inflammatory innate immune response in patients with and without T2D.

MATERIALS AND METHODS

Plasma levels of total GLP-1, IL-6, and PCT were estimated on admission and during hospitalisation in 61 patients (17 with T2D) with non-severe and severe COVID-19.

RESULTS

COVID-19 patients demonstrated ten-fold increase of IL-6 levels regardless of disease severity. Increased admission GLP-1 levels (p = 0.03) accompanied by two-fold increased PCT were found in severe as compared with non-severe patients. Moreover, GLP-1 and PCT levels were significantly increased in non-survived as compared with survived patients at admission (p = 0.01 and p = 0.001, respectively) and at 5 to 6 days of hospitalisation (p = 0.05). Both non-diabetic and T2D patients demonstrated a positive correlation between GLP-1 and PCT response (r = 0.33, p = 0.03, and r = 0.54, p = 0.03, respectively), but the intensity of this joint pro-inflammatory/GLP-1 response was modulated by T2D. In addition, hypoxaemia down-regulated GLP-1 response only in T2D patients with bilateral lung damage.

CONCLUSIONS

The persistent joint increase of endogenous GLP-1 and PCT in severe and fatal COVID-19 suggests a role of concomitant bacterial infection in disease exacerbation. Early elevation of endogenous GLP-1 may serve as a new biomarker of COVID-19 severity and fatal outcome.

Detecting Diabetic Ketoacidosis with Infection: Combating a Life-Threatening Emergency with Practical Diagnostic Tools

BACKGROUND

Diabetic ketoacidosis (DKA) is a life-threatening acute complication of diabetes mellitus and can lead to patient demise if not immediately treated. From the recent literature, the diabetic ketoacidosis mortality rate, depending on age, is 2-5%. Insulin discontinuation and infection remain the two most common triggers for diabetic ketoacidosis. About 50% of cases of ketoacidosis result from bacterial infections like urinary tract infections and pneumonia. It is also important to diagnose the presence of infection in diabetic ketoacidosis patients to prevent the excessive use of antibiotics, which may lead to antibiotic resistance. Although performing bacterial culture is confirmatory for the presence or absence of bacterial infection, the time required to obtain the result is long. At the same time, emergency treatment needs to be started as early as possible.

METHODS

This narrative review examines various septic markers to identify the appropriate tools for diagnosis and to distinguish between diabetic ketoacidosis with and without infection. Electronic databases were searched using the Google engine with the keywords "Diabetes Mellitus", "Diabetic Ketoacidosis", "Infection with Diabetic Ketoacidosis", "biomarkers for infection in Diabetic Ketoacidosis", "Procalcitonin", "Inflammatory cytokines in DKA", "Lactic acidosis in DKA", and "White blood cell in infection in DKA".

RESULTS

This narrative review article presents the options for diagnosis and also aims to create awareness regarding the gravity of diabetic ketoacidosis with infection and emphasizes the importance of early diagnosis for appropriate management. Diabetes mellitus is a clinical condition that may lead to several acute and chronic complications. Acute diabetic ketoacidosis is a life-threatening condition in which an excess production of ketone bodies results in acidosis and hypovolemia. Infection is one of the most common triggers of diabetic ketoacidosis. When bacterial infection is present along with diabetic ketoacidosis, the mortality rate is even higher than for patients with diabetic ketoacidosis without infection. The symptoms and biomarkers of diabetic ketoacidosis are similar to that of infection, like fever, C reactive protein, and white blood cell count, since both create an environment of systemic inflammation. It is also essential to distinguish between the presence and absence of bacterial infection to ensure the appropriate use of antibiotics and prevent antimicrobial resistance. A bacterial culture report is confirmatory for the existence of bacterial infection, but this may take up to 24 h. Diagnosis needs to be performed approximately in the emergency room upon admission since there is a need for immediate management. Therefore, researching the possible diagnostic tools for the presence of infection in diabetic ketoacidosis patients is of great importance. Several of such biomarkers have been discussed in this research work.

Dynamics of Urinary Extracellular DNA in Urosepsis

Extracellular DNA (ecDNA) is a promising candidate marker for the early diagnosis and monitoring of urinary tract infections (UTIs). The aim of our study is to describe the dynamics of ecDNA in the plasma and urine of patients with urosepsis as well as in a mouse model of UTI. Samples of blood and urine were collected from adult patients with UTIs and obstructive uropathy (n = 36) during the first 3 days at the hospital and during a follow-up. Bacterial burden and urinary ecDNA were evaluated in a mouse UTI model (n = 26) at baseline; 24, 48, and 72 h after UTI induction; and 7 days after UTI induction. The plasma ecDNA did not change during urosepsis, but the plasma DNase activity increased significantly at the follow-up. The urinary ecDNA decreased significantly during hospitalization and remained low until the follow-up (90% lower vs. admission). No change was seen in the urinary DNase activity. C-reactive protein (CRP) and procalcitonin are positively correlated with plasma and urinary ecDNA. A UTI caused sepsis in 23% of mice. The urinary ecDNA decreased by three-fold and remained low until day 7 post-infection. Urinary bacterial burden is correlated with urinary ecDNA. Urinary ecDNA is a potential non-invasive marker for monitoring the effects of treatment during urosepsis and is related to UTI progression in the experimental animal model.

Bacterial infections and fever after hepatocellular carcinoma ablation therapy: Predictive role of procalcitonin

AIM OF THE STUDY

Hepatocellular carcinoma (HCC) is a leading cause of mortality among patients with liver cirrhosis. According to the current practice guidelines, different ablations are used either as curative or palliative therapies. The current study aimed at determining bacterial infections as causes of fever and the predictive role of procalcitonin (PCT) among patients with HCC who had ablation therapy.

MATERIAL AND METHODS

This cross sectional study was carried out on 100 patients with HCC during the period from November 2019 to December 2021. All patients were evaluated by full history taking, clinical examination, complete blood picture (CBC), liver biochemistry, coagulation profile, kidney function, C-reactive protein (CRP), serum PCT and blood cultures. All were done for all participants at the 4th day follow-up after the procedures of ablation. HCC was treated according to the guidelines.

RESULTS

The frequency of fever after HCC ablation was 64% with variable intensities. Bacterial cultures were positive in 20 patients (20%). Twenty-four out of 100 patients had abnormally high PCT level. There was a highly statistically significant increase of PCT level in patients with a high CRP count and positive blood culture, p < 0.05. There was a statistically significant correlation between increased levels of PCT and levels of CRP, WBCs, albumin, AST, ALT, degree of fever, creatinine and BUN.

CONCLUSIONS

Bacterial infection accounts for 20% of fever among HCC patients after ablation therapy. PCT is 100% sensitive and specific for detection of the bacterial causes of fever among those patients.

Diagnostic and Prognostic Roles of Procalcitonin and Other Tools in Community-Acquired Pneumonia: A Narrative Review

Community-acquired pneumonia (CAP) is among the most common causes of death and one of the leading healthcare concerns worldwide. It can evolve into sepsis and septic shock, which have a high mortality rate, especially in critical patients and comorbidities. The definitions of sepsis were revised in the last decade as "life-threatening organ dysfunction caused by a dysregulated host response to infection". Procalcitonin (PCT), C-reactive protein (CRP), and complete blood count, including white blood cells, are among the most commonly analyzed sepsis-specific biomarkers also used in pneumonia in a broad range of studies. It appears to be a reliable diagnostic tool to expedite care of these patients with severe infections in the acute setting. PCT was found to be superior to most other acute phase reactants and indicators, including CRP as a predictor of pneumonia, bacteremia, sepsis, and poor outcome, although conflicting results exist. In addition, PCT use is beneficial to judge timing for the cessation of antibiotic treatment in most severe infectious states. The clinicians should be aware of strengths and weaknesses of known and potential biomarkers in expedient recognition and management of severe infections. This manuscript is intended to present an overview of the definitions, complications, and outcomes of CAP and sepsis in adults, with special regard to PCT and other important markers.

PROCALCITONIN GUIDED ANTIBIOTIC STEWARDSHIP: A BALKAN EXPERT CONSENSUS STATEMENT

Sepsis as a consequence of infection is a frequent cause of death among critically ill patients. The most common sites of infection are lover respiratory tract, abdominal, urinary tract and catheter-associated blood stream infections. Early empiric, broad-spectrum therapy in those with severe sepsis and/or shock with the aim of reducing mortality may lead to antibiotic overuse, resistance and increased costs. Among numerous serum biomarkers, procalcitonin (PCT) has proved to be one of the most reliable ones in the diagnosis of sepsis. An important means of limiting antibiotic resistance is the antibiotic stewardship program, especially in intensive care units with critically ill patients and prevalence of multiple drug-resistant pathogens. The PCT-guided antibiotic stewardship was first started in Western Europe and Asia-Pacific countries, as well as in the United States. Considering that this method has proven to be effective in reducing antibiotic consumption while improving clinical outcome, a group of experts from the Balkan region decided to make their own recommendations and PCT protocol. When creating this protocol for initiation and duration of antibiotic treatment, they especially reviewed the literature for lower respiratory tract infection and sepsis. In the protocol, they have included the severity of illness, clinical assessment, and PCT levels. Developing a consensus on the clinical algorithm by eminent experts/specialists in various fields of medicine should enable clinicians to use PCT for initiation of antibiotic therapy and monitoring PCT to stop antibiotics earlier. It is crucial that the PCT-guided algorithm becomes an integral part of institutional stewardship program.

Diagnostic and therapeutic value of biomarkers in urosepsis

Urosepsis is sepsis caused by urogenital tract infection and is one of the most common critical illnesses in urology. If urosepsis is not diagnosed early, it can rapidly progress and worsen, leading to increased mortality. In recent years, with the increase of urinary tract surgery, the incidence of urosepsis continues to rise, posing a serious threat to patients. Early diagnosis of urosepsis, timely and effective treatment can greatly reduce the mortality of patients. Biomarkers such as WBC, NLR, PCT, IL-6, CRP, lactate, and LncRNA all play specific roles in the early diagnosis or prognosis of urosepsis. In addition to the abnormal increase of WBC, we should be more alert to the rapid decline of WBC. NLR values were superior to WBC counts alone in predicting infection severity. Compared with several other biomarkers, PCT values can differentiate between bacterial and non-bacterial sepsis. IL-6 always has high sensitivity and specificity for the diagnosis of sepsis, and CRP also has high sensitivity and specificity for the diagnosis of urosepsis. Lactic acid is closely related to the prognosis of patients with urosepsis. LncRNAs may be potential biomarkers of urosepsis. This article summarizes the main biomarkers, hoping to provide a reference for the timely diagnosis and evaluation of urosepsis.

Procalcitonin as a Potential Biomarker in the Study of Babesiosis Caused by B. microti

Procalcitonin is gaining momentum in the study of protozoal sepsis, but its utility as a biomarker has yet to be fully discovered in human babesiosis. A total of 33 cases of acute babesiosis dating between 2012 and 2019 were retrospectively collected from Stony Brook University Hospital (SBUH) and Stony Brook South Hampton Hospital (SHH), both of which are located on Long Island, NY. Cases were cross-referenced for the need for ICU admission, and the procalcitonin levels were measured by the use of BRAHMS Elecsys assay at SBUH and BRAHMS Architect assay at SHH. Our study demonstrated that the log-transformed procalcitonin levels had a linear correlation with log-transformed maximum parasitemia, which suggests that procalcitonin directly correlates with parasitemia values. Furthermore, when comparing values that predict ICU admission, our ROC analysis of procalcitonin demonstrated similar AUC values to the percentage of parasitemia, suggesting that procalcitonin may assist in determining the severity of disease. We demonstrate that procalcitonin may directly correlate with the parasitemia percentage and have prognostic capabilities, which suggests that procalcitonin may have biomarker potential in human babesiosis.

Infections in Burn Patients: A Retrospective View over Seven Years

Backgroundand objectives: Burn patients represent a challenging cohort because the injuries entail a vulnerability to colonisation by microorganisms. The ensuing infections can lead to serious complications and, in many cases, to the death of the burn patient. Surgical intervention and wound dressings, as well as antibiotic treatment, are crucial for optimising the treatment of the patient. Materialand Methods: In this retrospective analysis, we analysed the treatment course, antibiotic therapy, and general complications of 252 burn patients with second- or third-degree burns over a time span of 7 years. Results: Patients who developed infections tended to have, on average, a higher total body surface area (TBSA), higher abbreviated burn severity index (ABSI) scores, and longer hospital stays. Patients who were admitted to the burn unit after 2006 had significantly shorter stays in the burn unit. TBSA and ABSI scores were lower in the patient cohort admitted after 2006. Patients exhibiting a TBSA greater than 30% had significantly longer hospital stays and antibiotic treatment periods. TBSA and ABSI scores were significantly higher in patients who died. The results of binary logistic regression indicate that a higher ABSI score increases the odds ratio of developing an infection. Bacteria number had no significant effect on the odds of patient death but positively influenced the odds ratio of developing an infection. TBSA was negatively associated with the risk of developing an infection and was an insignificant predictor of mortality. Conclusions: To gauge the optimal treatment for a burn patient, it is crucial for practitioners to correctly select, dose, and time antibiotics for the patient. Monitoring bacterial colonisation is vital to nip rising infection in the bud and ensure the correct antibiotic selection. This will help prevent the development of multi-resistant bacteria.

Extra-pulmonary applications of procalcitonin: an updated literature review

INTRODUCTION

: Procalcitonin (PCT) is a biomarker with established performance in the differentiation between bacterial and viral infections, predominantly in pulmonary infections, as well as the diagnosis and prognosis of bacterial sepsis. However, the role of PCT in extra-pulmonary infections is not well described.

AREAS COVERED

: We reviewed the role of PCT in commonly experienced extra-pulmonary infections including meningitis, diabetic foot infection, prosthetic joint infection, osteomyelitis, and skin and soft tissue infection. PubMed and Medline online libraries were searched, from 2013 till 2022, for relevant articles.

EXPERT OPINION

: For meningitis, PCT could distinguish bacterial from viral meningitis. PCT distinguished septic arthritis from different types of arthritis but had variable performance in discriminating septic arthritis from crystal arthropathy. For periprosthetic joint infections, results were inconclusive. PCT had a potential role in diagnosis of more complex infections such as osteomyelitis and diabetic foot infections, but further studies are needed for a definitive cutoff. In skin and soft tissue infections, PCT performance was more variable requiring further investigation to define cutoff for the discrimination of cellulitis from necrotizing fasciitis. We find that PCT performed best for meningitis and helps in the reduction of unnecessary antibiotic treatment, but has variable outcomes with other extra-pulmonary infections.

Use of temperature changes and pro-inflammatory biomarkers to diagnose bacterial infections in patients with severe cerebral trauma

Background: In patients undergoing neurosurgeries, inflammation and infection are strongly related; however, inflammation can be present without infection. Midregional proadrenomedullin (MR-proADM) is a relatively new sepsis biomarker that is rarely used clinically. Recently, the concept of DiffTemp was introduced, that is, a >1°C rise from individual normal temperature accompanied by malaise, as a more accurate definition of temperature assessed as fever. The aim of the present study was to examine the importance of C-reactive protein (CRP), white blood cells, procalcitonin, and MR-proADM levels and DiffTemp.Methods: This prospective, comparative study had a quantitative approach. Forty-two patients, aged >18 years and presenting with severe cerebral trauma were included from a neurosurgery intensive care unit. The outcome variable was infection; group 0, no infection (n=11); group 1, suspected infection (n=15); and, group 2, confirmed infection (n=16). Group assignments were performed using biomarkers, medical records, bacterial cultures, and International Classification of Diseases-10, and by the clinical assessment of criteria for nosocomial infections by a neurosurgeon.Results: On comparing groups 1 and 2, MR-proADM and DiffTemp were associated with a higher risk of confirmed infection (odds ratio, 5.41 and 17.14, respectively). Additionally, DiffTemp had a 90.9% specificity in patients with no infection and a 93.8% sensitivity in patients with confirmed infections. CRP and procalcitonin levels were not associated with an increased risk of confirmed infection.Conclusion: Increased levels of MR-proADM were associated with a higher risk of confirmed infection. DiffTemp was associated with a higher risk of having a confirmed infection.

Optimization of flow path parameters for enhanced sensitivity lateral flow devices

Lateral flow devices (LFDs) or lateral flow tests (LFTs) are one of the most widely used biosensor platforms for point-of-care (POC) diagnostics. The basic LFD design has remained largely unchanged since its first appearance, and this has limited LFD use in clinical applications due to a general lack of analytical sensitivity. We report here a comprehensive study of the use of laser-patterned geometric control barriers that influence the flow dynamics within an LFD, with the specific aim of enhancing LFD sensitivity and lowering the limit of detection (LOD). This control of sample flow produces an increase in the time available for optimizing the binding kinetics of the implemented assay. The geometric modification to the flow path is in the form of a constriction that is produced by depositing a photo-sensitive polymer onto the nitrocellulose membrane which when polymerized, creates impermeable barrier walls through the depth of the membrane. Both the position of the constriction within the flow path and the number of constrictions allow for an increase in the sensitivity because of a slower overall flow rate within the test and a larger volume of sample per unit width of the test line. For these high sensitivity LFDs (HS-LFD), through optimization of the constriction position and addition of a second constriction we attained a 62% increase in test line color intensity for the detection of procalcitonin (PCT) and were also able to lower the LOD from 10 ng/mL to 1 ng/mL. In addition, of relevance for future commercial exploitation, this also significantly decreases the antibody consumption per device leading to reduced costs for test production. We have further tested our HS-LFD with contrived human samples, validating its application for future clinical use.

Rapid Quantum Magnetic IL-6 Point-of-Care Assay in Patients Hospitalized with COVID-19

Interleukin-6 (IL-6) has been linked to several life-threatening disease processes. Developing a point-of-care testing platform for the immediate and accurate detection of IL-6 concentrations could present a valuable tool for improving clinical management in patients with IL-6-mediated diseases. Drawing on an available biobank of samples from 35 patients hospitalized with COVID-19, a novel quantum-magnetic sensing platform is used to determine plasma IL-6 concentrations. A strong correlation was observed between IL-6 levels measured by QDTI10x and the Luminex assay (r = 0.70, p-value < 0.001) and between QDTI80x and Luminex (r = 0.82, p-value < 0.001). To validate the non-inferiority of QDTI to Luminex in terms of the accuracy of IL-6 measurement, two clinical parameters—the need for intensive care unit admission and the need for mechanical intubation—were chosen. IL-6 concentrations measured by the two assays were compared with respect to these clinical outcomes. Results demonstrated a comparative predictive performance between the two assays with a significant correlation coefficient. Conclusion: In short, the QDTI assay holds promise for implementation as a potential tool for rapid clinical decision in patients with IL-6-mediated diseases. It could also reduce healthcare costs and enable the development of future various biomolecule point-of-care tests for different clinical scenarios.

Role of procalcitonin as a predictor of clinical outcomes in hospitalized patients with COVID-19

Objectives

In this study, we aimed to determine the correlation between procalcitonin (PCT) levels and clinical outcomes including in-hospital mortality, intensive care unit (ICU) length of stay, and hospital length of stay in patients hospitalized with COVID-19.

Methods

Clinical, laboratory, and demographic data of 223 patients who met inclusion criteria were analyzed. PCT measurements of 0.25 ng/mL and 0.50 ng/mL were used to stratify patients into 2 mutually exclusive groups.

Results

Patients with PCT above 0.25 ng/mL on admission had significantly elevated Acute Physiology and Chronic Health Evaluation II scores (9 vs 8; P = 0.042) and C-reactive proteins levels (111 μg/mL vs 79 μg/mL; P = 0.007). A multivariable binary logistic regression model demonstrated no relationship between PCT and mortality (OR = 1.00; 95% Cl: 0.97 to 1.02; P = 0.713). Kaplan-Meier analysis revealed no statistical evidence of a difference between PCT groups and hospital length of stay (P = 0.144 for 0.25 ng/mL, P = 0.368 for 0.50 ng/mL) or intensive care unit length of stay (P = 0.986 for 0.25 ng/mL, P = 0.771 for 0.50 ng/mL).

Conclusions

Elevated PCT levels were associated with severity of illness but did not correlate with in-hospital mortality, hospital length of stay, or ICU length of stay.

Implications of Using Host Response-Based Molecular Diagnostics on the Management of Bacterial and Viral Infections: A Review

Host-based diagnostics are a rapidly evolving field that may serve as an alternative to traditional pathogen-based diagnostics for infectious diseases. Understanding the exact mechanisms underlying a host-immune response and deriving specific host-response signatures, biomarkers and gene transcripts will potentially achieve improved diagnostics that will ultimately translate to better patient outcomes. Several studies have focused on novel techniques and assays focused on immunodiagnostics. In this review, we will highlight recent publications on the current use of host-based diagnostics alone or in combination with traditional microbiological assays and their potential future implications on the diagnosis and prognostic accuracy for the patient with infectious complications. Finally, we will address the cost-effectiveness implications from a healthcare and public health perspective.

Role of Polypeptide Inflammatory Biomarkers in the Diagnosis and Monitoring of COVID-19

The COVID-19 (coronavirus disease 2019) pandemic that took over the world in December 2019 has had everlasting devastating impacts on the lives of people globally. It manifests a huge symptom spectrum ranging from asymptomatic to critically ill patients with an unpredictable outcome. Timely diagnosis and assessment of disease severity is imperative for effective treatment. Possibilities exist that by the time symptoms appear the viral load might increase beyond control. However, it is advisable to get adequately diagnosed as soon as the first symptom appears. There is an immediate requirement of reliable biomarkers of COVID-19 manifesting an early onset for effective clinical management, stratification of high risk patients and ensuring ideal resource allocation. In this review, we attempt to explore and describe important polypeptide inflammatory biomarkers, namely C-reactive protein, Procalcitonin, Ferritin, Lactate Dehydrogenase, Serum amyloid A, Interleukin-6, Tumor necrosis factor-alpha and LIGHT used in the detection and management of COVID-19. Viral pathogenesis and the role of these inflammatory biomarkers is highlighted, based on the evidences available till date. An integrative data monitoring along with their correlation with the natural disease progression is of utmost importance in the management of COVID-19. So further research and in-depth analysis of these biomarkers is warranted in the present scenario.

Semi-quantitative detection of inflammatory biomarkers using a laser-patterned multiplexed lateral flow device

Inflammatory markers including C-reactive protein (CRP) and procalcitonin (PCT) have been shown to be useful biomarkers to improve triage speed and prevent the inappropriate use of antibiotics for infections such as pneumonia. Here, we present a novel and exciting solution to guide the administration of antibiotic treatment via rapid, semi-quantitative and multiplexed detection of CRP and PCT using an advanced lateral flow device (LFD) designed to have multiple parallel flow-paths, produced via the precise laser-based partitioning of the single flow-path of a standard LFD. Each flow-path within this multiplexed LFD has a unique detection capability which permits tailored detection of CRP within a predefined cut-off range (20 μg/mL - 100 μg/mL) and PCT above a pre-defined threshold (0.5 ng/mL). We demonstrate the use of this LFD in the successful detection of CRP and PCT semi-quantitatively within spiked human serum samples. This multiplexed near-patient assay has potential for development into a rapid triage and treatment of patients with suspected pneumonia.

Use of infection biomarkers in the emergency department

The use of infection biomarkers in the emergency department is discussed in terms of their possible contributions to diagnostic-prognostic uncertainties, appropriate antibiotic treatments, and triage and follow-up planning. Procalcitonin (PCT), C-reactive protein (CRP), proadrenomedullin (proADM), and presepsin are among the most discussed infection biomarkers for use in the emergency department. Due to the variable sensitivity results and cutoff values, there are insufficient data to recommend the widespread use of CRP and procalcitonin (PCT) for the diagnosis and prognosis of infection in the emergency department. However, these biomarkers can be used for appropriate antibiotic use in selected infection groups, such as community-acquired pneumonia, especially to reduce unnecessary antibiotic prescribing. With its prognostic superiority over other biomarkers and its contribution to prognostic score systems in community-acquired pneumonia (CAP), proADM can be used to predict hospitalization, preferably within the scope of clinical studies. Although presepsin has been shown to have some advantages over other biomarkers to rule out sepsis, there are insufficient data for its clinical use in the emergency department.

SERUM PROCALCITONIN AS A PROGNOSTIC MARKER IN ACUTE SEVERE ULCERATIVE COLITIS: A PROSPECTIVE STUDY

BACKGROUND

Procalcitonin may be increased in active ulcerative colitis (UC). We investigated the role of procalcitonin in predicting response in acute severe UC (ASUC).

METHODS

Consecutive patients with ASUC diagnosed on basis of Truelove and Witts criteria were enrolled. Serum procalcitonin levels for consecutive patients were measured at admission and day 3. We assessed role of procalcitonin values at presentation and at day 3 in assessing response on day 3 (Oxford's criteria) and need for second line therapy (day 28).

RESULTS

Of fifty patients (23 males, mean age: 35.98±13.8 years), 16 did not respond (day 3). Ten (20%) patients required second-line therapy. Baseline procalcitonin was significantly associated with response on day 3 (P=0.016). There was no association between day 1 or day 3 procalcitonin and need for second-line rescue therapy.

CONCLUSION

Serial procalcitonin is not an effective biomarker for predicting outcomes or need for second line therapy in ASUC.

Impact of Pharmacist-Directed Simplified Procalcitonin Algorithm on Antibiotic Therapy in Critically Ill Patients With Sepsis

Purpose

The purpose was to determine whether a simplified procalcitonin (PCT) algorithm guided by pharmacist recommendations reduces antibiotic duration of therapy in critically ill patients with suspected sepsis.

Methods

This was a single-centered pre-post study conducted at a 1368-bed community teaching hospital in the United States. A prospective cohort with pharmacist intervention utilizing a simplified PCT algorithm was compared with a retrospective historical cohort with standard therapy. Adult patients admitted to the intensive care unit (ICU) with suspected sepsis who received intravenous antibiotics were included. A pharmacist recommended continuation or discontinuation of antibiotics based on the PCT level per our algorithm and full clinical assessment of the patient. Primary outcome was total duration of antibiotic therapy. Secondary outcomes were ICU and hospital length of stay (LOS), reinitiation of antibiotic therapy within 72 hours of discontinuation, and 28-day in-hospital mortality.

Results

From September 2017 to May 2018, 360 patients were screened for eligibility. Of these, 26 patients were included in the PCT group and 26 patients in the standard therapy group. Baseline characteristics were similar between groups. A significant difference in duration of antibiotic therapy was detected with a median of 9 days in the PCT group versus 12 days in the standard therapy group (P = .02). There were no significant differences in secondary endpoints of ICU and hospital LOS, reinitiation of antibiotics at 72 hours, or 28-day mortality.

Conclusion

Use of a simplified PCT algorithm with pharmacist-guided recommendations significantly reduced the duration of antibiotic therapy in critically ill patients with sepsis.

Serum procalcitonin levels associate with Clostridioides difficile infection in patients with inflammatory bowel disease

BACKGROUND

Clostridioides difficile infection (CDI) is a major cause of morbidity among patients with inflammatory bowel disease (IBD). Diagnostic biomarkers for early detection of CDI are needed in clinical practice. The relationship between serum procalcitonin and CDI in IBD patients has not been investigated so far. Therefore, we aimed to evaluate the usefulness of measuring serum procalcitonin level to detect CDI in patients with the flare of IBD.

METHODS

One hundred twenty patients with IBD were enrolled in this study. Bacterial identification was performed using standard microbiological and molecular methods. The serum procalcitonin levels were measured in all patients. Receiver operating characteristic (ROC) curve analysis was applied to assess the value of procalcitonin for the prediction of CDI among IBD patients.

RESULTS

The median serum procalcitonin level was significantly increased in IBD patients with CDI compared to non-CDI IBD patients (0.69 ng/mL vs 0.32 ng/mL). In univariate analysis, log10 procalcitonin was associated with CDI (OR 2.81, 95% CI 1.54-4.09, P-value < 0.001). Procalcitonin 1.1 ng/mL was 85% sensitive and 88% specific for the prediction of CDI. In the multivariable model including the covariates log10 procalcitonin, age, hospitalization, type of IBD, duration of the disease, and antibiotic usage, procalcitonin showed a robust association with CDI (OR 4.59, 95% CI 2.49-6.70, P-value < 0.001). An elevated procalcitonin level was associated with the presence of CDI among IBD patients.

CONCLUSIONS

Our results indicate that procalcitonin level can be a good candidate biomarker for assessing the CDI in IBD patients. Further studies are required to decipher whether procalcitonin can predict CDI therapy or its recurrence.

Clinical Practice Guideline by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America: 2021 Guideline on Diagnosis and Management of Acute Hematogenous Osteomyelitis in Pediatrics

This clinical practice guideline for the diagnosis and treatment of acute hematogenous osteomyelitis (AHO) in children was developed by a multidisciplinary panel representing Pediatric Infectious Diseases Society (PIDS) and the Infectious Diseases Society of America (IDSA). This guideline is intended for use by healthcare professionals who care for children with AHO, including specialists in pediatric infectious diseases, orthopedics, emergency care physicians, hospitalists, and any clinicians and healthcare providers caring for these patients. The panel's recommendations for the diagnosis and treatment of AHO are based upon evidence derived from topic-specific systematic literature reviews. Summarized below are the recommendations for the diagnosis and treatment of AHO in children. The panel followed a systematic process used in the development of other IDSA and PIDS clinical practice guidelines, which included a standardized methodology for rating the certainty of the evidence and strength of recommendation using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. A detailed description of background, methods, evidence summary and rationale that support each recommendation, and knowledge gaps can be found online in the full text.

Proadrenomedullin Predicts Severe Disease in Children With Suspected Community-acquired Pneumonia

BACKGROUND

Proadrenomedullin (proADM), a vasodilatory peptide with antimicrobial and anti-inflammatory properties, predicts severe outcomes in adults with community-acquired pneumonia (CAP) to a greater degree than C-reactive protein and procalcitonin. We evaluated the ability of proADM to predict disease severity across a range of clinical outcomes in children with suspected CAP.

METHODS

We performed a prospective cohort study of children 3 months to 18 years with CAP in the emergency department. Disease severity was defined as mild (discharged home), mild-moderate (hospitalized but not moderate-severe or severe), moderate-severe (eg, hospitalized with supplemental oxygen, broadening of antibiotics, complicated pneumonia), and severe (eg, vasoactive infusions, chest drainage, severe sepsis). Outcomes were examined using proportional odds logistic regression within the cohort with suspected CAP and in a subset with radiographic CAP.

RESULTS

Among 369 children, median proADM increased with disease severity (mild: median [IQR], 0.53 [0.43-0.73]; mild-moderate: 0.56 [0.45-0.71]; moderate-severe: 0.61 [0.47-0.77]; severe: 0.70 [0.55-1.04] nmol/L) (P = .002). ProADM was significantly associated with increased odds of developing severe outcomes (suspected CAP: OR, 1.68; 95% CI, 1.2-2.36; radiographic CAP: OR, 2.11; 95% CI, 1.36-3.38) adjusted for age, fever duration, antibiotic use, and pathogen. ProADM had an AUC of 0.64 (95% CI, .56-.72) in those with suspected CAP and an AUC of 0.77 (95% CI, .68-.87) in radiographic CAP.

CONCLUSIONS

ProADM was associated with severe disease and discriminated moderately well children who developed severe disease from those who did not, particularly in radiographic CAP.

Clinical Outcome Predictive Value of Procalcitonin in Patients Suspected with Infection in the Emergency Department

Procalcitonin (PCT) may be useful for early risk stratification in the emergency department (ED), but the transposition of published data to routine emergency practice is sometimes limited. An observational retrospective study was conducted in the adult ED of the Reims University Hospital (France). Over one year, 852 patients suspected of infection were included, of mean age 61.7 years (SD: 22.6), and 624 (73.2%) were hospitalized following ED visit. Overall, 82 (9.6%) patients died during their hospitalization with an odds ratio (OR) of 5.10 (95% CI: 2.19-11.87) for PCT ≥ 0.5, in multivariate logistic regression analyses. Moreover, 78 (9.2%) patients were admitted to an ICU, 74 (8.7%) had attributable bacteremia, and 56 (6.6%) evolved toward septic shock with an OR of 4.37 (2.08-9.16), 6.38 (2.67-15.24), and 6.38 (2.41-16.86), respectively, for PCT ≥ 0.5. The highest discriminatory values were found for patients with age <65 years, but PCT lost its discrimination power for in-hospital mortality in patients with a bronchopulmonary infection site or a temperature ≥37.8°C and for ICU admission in patients with severe clinical presentations. PCT could be helpful in risk stratification, but several limitations must be considered, including being sometimes outperformed by a simple clinical examination.

Serum IL-6 and procalcitonin are two promising novel biomarkers for evaluating the severity of COVID-19 patients

ABSTRACT

To evaluate the development of coronavirus disease 2019 (COVID-19), the roles of interleukin 6 (IL-6) and procalcitonin (PCT) were assessed to diagnose severe COVID-19.Between January and February 2020, 100 consecutive patients with confirmed COVID-19 were included and divided into common (n = 56), severe (n = 28), and critical (n = 16) groups.IL-6 and PCT levels were assayed and compared among groups. IL-6 levels were significantly different among groups (common, 23.93±9.64 pg/mL; severe, 69.22 ± 22.98 pg/mL; critical, 160.34 ± 26.15 pg/mL; P < .05), and there was also a significant difference in the levels of PCT among groups (common, 0.23 ± 0.13 ng/mL; severe, 0.38 ± 0.16 ng/mL; critical, 0.73 ± 0.36 ng/mL; P < .05). Further analysis showed that patients in the critical group had the highest levels of IL-6 and PCT, and those in the common group had the lowest levels (all P < .05).IL-6 and PCT are associated with the severity of COVID-19, and thus have potential value in the diagnosis of COVID-19.

Blood Procalcitonin Level as a Diagnostic Marker of Pediatric Bacterial Meningitis: A Systematic Review and Meta-Analysis

Early diagnosis and treatment of bacterial meningitis in children are essential, due to the high mortality and morbidity rates. However, lumbar puncture is often difficult, and cerebrospinal fluid (CSF) culture takes time. This meta-analysis aims to determine the diagnostic accuracy of blood procalcitonin for detecting bacterial meningitis in children. We conducted a systematic search on electronic databases to identify relevant studies. Pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were calculated, and a hierarchical summary receiver operating characteristic curve and area under the curve (AUC) were determined. Eighteen studies with 1462 children were included in the analysis. The pooled sensitivity, specificity, and the DOR of blood procalcitonin for detecting bacterial meningitis were 0.87 (95% confidence interval (CI): 0.78–0.93); 0.85 (95% CI: 0.75–0.91), and 35.85 (95% CI: 10.68–120.28), respectively. The AUC for blood procalcitonin was 0.921. Blood procalcitonin also showed higher diagnostic accuracy for detecting bacterial meningitis than other conventional biomarkers, including serum C-reactive protein and leukocyte count, CSF leukocyte and neutrophil count, and CSF protein and glucose levels. Blood procalcitonin can be a good supplemental biomarker with high diagnostic accuracy in detecting bacterial meningitis in children.

The Effect of Pre-TURP Bladder Irrigation with 0.2% Chlorhexidine in Patients with Foley Catheter Regarding Postoperative Bacteremia Decrease

Background: Transurethral resection of the prostate (TURP) has been widely used for patients suffering from bladder colonization with bacteria, increasing the probability of bacteremia and sepsis despite consuming prophylaxis antibiotics. Objectives: The study aimed to evaluate the effect of pre- TURP bladder irrigation with 0.2% chlorhexidine in reducing postoperative bacteremia. Methods: This clinical trial study was conducted on 60 benign prostatic hyperplasia (BPH) patients who were candidates for TURP in the urology department of Al-Zahra Hospital. All patients suffered from urinary catheters, and they were allocated into two groups (n = 30). Antibiotic prophylaxis was prescribed for all the patients. In the case group, the bladder was rinsed by chlorhexidine 0.2% before TURP; however, and the bladder in the control group was rinsed by distilled water. Postoperative bacteremia were evaluated using procalcitonin (PCT) measurement and BACTEC automated blood culture six hours after surgery. Results: Positive BACTEC blood culture was observed in three (10%) and no (0%) patients in the control and case groups, respectively (P = 0.071). Moreover, 6.6 % and 46.6 % of the patients in the control group had low and high PCT levels, respectively. Furthermore, 40 % and 6.66 % of the patients in the case group had low and high PCT levels, respectively. There was a significant difference between the two groups in terms of the PCT level (P < 0.01). Conclusions: The frequency of patients with a high PCT level was higher in the control group than in the case group, suggesting that chlorhexidine in the catheterized patients undergoing TURP reduced the number of bacteria in the bladder.

Antimicrobial stewardship perspectives from a New York City hospital during the COVID-19 pandemic: Challenges and opportunities

Purpose

To share challenges and opportunities for antimicrobial stewardship programs based on one center’s experience during the early weeks of the coronavirus disease 2019 (COVID-19) pandemic.

Summary

In the spring of 2020, New York City quickly became a hotspot for the COVID-19 pandemic in the United States, putting a strain on local healthcare systems. Antimicrobial stewardship programs faced diagnostic and therapeutic uncertainties as well as healthcare resource challenges. With the lack of effective antivirals, antibiotic use in critically ill patients was difficult to avoid. Uncertainty drove antimicrobial use and thus antimicrobial stewardship principles were paramount. The dramatic influx of patients, drug and equipment shortages, and the need for prescribers to practice in alternative roles only compounded the situation. Establishing enhanced communication, education, and inventory control while leveraging the capabilities of the electronic medical record were some of the tools used to optimize existing resources.

Conclusion

New York City was a unique and challenging environment during the initial peak of the COVID-19 pandemic. Antimicrobial stewardship programs can learn from each other by sharing lessons learned and practice opportunities to better prepare other programs facing COVID-19 case surges.

Temperature Plays an Essential Regulatory Role in the Tumor Immune Microenvironment

In recent years, emerging immunotherapy has been included in various malignant tumor treatment standards. Temperature has been considered to affect different pathophysiological reactions such as inflammation and cancer for a long time. However, in tumor immunology research, temperature is still rarely considered a significant variable. In this review, we discuss the effects of room temperature, body temperature, and the local tumor temperature on the tumor immune microenvironment from multiple levels and perspectives, and we discuss changes in the body's local and whole-body temperature under tumor conditions. We analyze the current use of ablation treatment-the reason for the opposite immune effect. We should pay more attention to the therapeutic potential of temperature and create a better antitumor microenvironment that can be combined with immunotherapy.

Dietary Supplementation of Carob and Whey Modulates Gut Morphology, Hemato-Biochemical Indices, and Antioxidant Biomarkers in Rabbits

This study aimed to evaluate the influence of the carob powder (CP) and sweet whey powder (WhP) inclusion into weaning feed on the gut morphology, hemato-biochemical parameters, and antioxidant biomarkers. The addition of 10 g/kg (basal diet +10 g/kg of CP, of WhP) or the mixture (5 g/kg of CP and 5 g/kg of WhP) in the rabbit's standard diet was assessed. A total of 40 weaned New Zealand White rabbits (4 weeks old) was distributed according to body weight (BW) into four treatments (n = 10) and the feed additives were provided for 7 weeks. Tissue samples and blood were obtained after slaughter. Final BW, daily weight gain, feed conversion ratio, intestinal morphology, and carcass dressing were positively affected by CP-WhP treatments compared with the control diet. Also, CP-WhP treatments significantly increased total proteins, calcium and iron levels, fecal cholesterol excretion, total antioxidants capacity, superoxide dismutase, and catalase in different tissues and significantly decreased total cholesterol, triglycerides, and glucose in blood serum. These changes were associated with a diminution of blood tumor necrosis factor alpha, lipid peroxidation, and carbonyl proteins in rabbit tissues. Both the additives separately and especially in the mix may enhance productive performance, protein profile, gut function, immunity, and antioxidant activity, with reducing lipid peroxidation, essential inflammatory mediator, and protein-carbonyl residues of growing rabbits. These findings suggest that CP-WhP dietary supplementation provides novel insights into a variety of bioactive compound mixtures with different beneficial modes of actions.

Clinical Usefulness of Acute-Phase Markers in Distinguishing between PFAPA and Other Exudative Tonsillitis Causes: A Methodological Study

BACKGROUND

We investigated the practical use of procalcitonin (PCT), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and complete blood count (CBC) parameters in distinguishing periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis syndrome (PFAPA) attacks from exudative tonsillitis associated with group A streptococcus (GAS) and Epstein-Barre virus (EBV).

METHODS

The study population consisted of cases with exudative tonsillitis who had been subsequently diagnosed as PFAPA, EBV, and GAS tonsillitis through a period of 6 years. We retrieved the CBC, ESR, CRP and PCT data from patients' medical records.

RESULTS

Of the patients, 47 (35.6%) had PFAPA, 36 (27.3%) had GAS and 49 (37.1%) had EBV tonsillitis. Median CRP, ESR and PCT values of patients with PFAPA were 78 (17-92) mg/dl, 44 (11-83) mm/h, 0.16 (0.01-1.45) ng/ml, respectively. The CRP and ESR levels were significantly higher in PFAPA and GAS groups compared with the EBV group (p = 0.001). There was no significant difference between the groups regarding the PCT levels.

CONCLUSION

The study indicated no benefit of PCT in distinguishing PFAPA from the others. However, we found that CRP, ESR, and CBC parameters could be useful in identifying PFAPA and GAS than EBV tonsillitis.

Evaluation of the necessity and the feasibility of the standardization of procalcitonin measurements: Activities of IFCC WG-PCT with involvement of all stakeholders

Procalcitonin (PCT) is an important biomarker for sepsis diagnosis and management. To date, there is no higher-order reference measurement procedure (RMP) and certified reference material to achieve global standardization of results and results traceability to the SI units. Although efforts have been made to harmonize PCT results, a number of comparison studies and external quality assessment (EQA) schemes show conflicting results regarding results comparability and to date, equivalence of PCT results across the assays remains questionable in absence of studies relying on commutable EQA materials. In this context, the IFCC initiated activities to fill these gaps through the creation of the working group on standardization of PCT assays that gathers experts from National Metrology Institutes, calibration laboratories, clinicians, biologists, EQA providers and assay manufacturers. Among the activities, a higher order RMP and commutable reference materials are under development to build a robust reference measurement system (RMS). A commutability study is being organized to identify EQA materials that are fit for purpose to reliably estimate the current comparability of PCT results. This work will make it possible to evaluate the necessity and the feasibility for establishing and maintaining a new RMS for PCT assays, if deemed necessary.

Dose Optimization of Vancomycin Using a Mechanism-based Exposure-Response Model in Pediatric Infectious Disease Patients

PURPOSE

This study aimed to determine the appropriate vancomycin dosage, considering patient size and organ maturation, by simulating the bacterial count and biomarker level for drug administration in pediatric patients with gram-positive bacterial (GPB) infections.

METHODS

Natural language processing for n-gram analysis was used to detect appropriate pharmacodynamic (PD) markers in infectious disease patients. In addition, a mechanism-based model was established to describe the systemic exposure and evaluate the PD marker simultaneously in pediatric patients. A simulation study was then conducted by using a mechanism-based model to evaluate the optimal dose of vancomycin in pediatric patients.

FINDINGS

C-reactive protein (CRP) was selected as a PD marker from an analysis of ~270,000 abstracts in PubMed. In addition, clinical results, including the vancomycin plasma concentrations and CRP levels of pediatric patients (n = 93), were collected from electronic medical records. The vancomycin pharmacokinetic model with allometric scaling and a maturation function was built as a one-compartment model, with an additional compartment for bacteria. Both the effects of vancomycin plasma concentrations on the destruction of bacteria and those of bacteria on CRP production rates were represented by using a maximum achievable effect model (E_max model). Simulation for dose optimization was conducted not only by using the final model but also by exploring the possibility of therapeutic failure based on the MICs of vancomycin for GPB. Clinical cure was defined as when the CRP level fell below the upper limit of the normal range. Our dose optimization simulations suggested a vancomycin dosage of 10 mg/kg every 8 h as the optimal maintenance dose for pediatric patients with a postconceptual age <30 weeks and 10 mg/kg every 6 h for older children, aged up to 12 years. In addition, the MIC of 3 μg/mL was assessed as the upper concentration limit associated with successful vancomycin treatment of GPB infections.

IMPLICATIONS

This study confirmed that the changes in bacterial counts and CRP levels were well described with mechanistic exposure-response modeling of vancomycin. This model can be used to determine optimal empiric doses of vancomycin and to improve therapeutic outcomes in pediatric patients with GPB.