Prognostic value of procalcitonin in hospitalized patients with lower respiratory tract infections

Chemo Markers as Biomarkers in Septic Shock: A Comprehensive Review of Their Utility and Clinical Applications

Sepsis is a life-threatening condition characterized by a dysregulated host response to infection, often leading to septic shock. Early diagnosis and prompt intervention are crucial for improving patient outcomes. Chemo markers, which are measurable biological substances associated with the pathophysiology of septic shock, have emerged as potential biomarkers for the identification, risk stratification, and management of this condition. This comprehensive review aims to thoroughly evaluate the utility and clinical applications of chemo markers in septic shock. The review begins by discussing the criteria for ideal chemo markers, including specificity, sensitivity, dynamic range, stability, non-invasiveness, and prognostic value. These characteristics ensure accurate diagnosis, early detection, effective monitoring, and prediction of clinical outcomes. Furthermore, the review explores the role of chemo markers in monitoring treatment response and disease progression, highlighting their ability to serve as objective indicators for assessing the effectiveness of interventions and making timely adjustments in management strategies. Moreover, the prognostic value of chemo markers in predicting outcomes is discussed, emphasizing their association with mortality, hospital stays, and the development of complications. Integration of chemo markers into prognostic models or scoring systems enhances risk stratification and informs therapeutic decisions. The review also delves into recent advances in chemo marker research and technology, emphasizing the potential for discovering novel chemo markers with enhanced diagnostic and prognostic capabilities. It highlights the use of high-throughput proteomics, genomics, and transcriptomics in identifying specific molecular signatures associated with septic shock. This contributes to a deeper understanding of the complex immune and inflammatory responses involved. In conclusion, chemo markers have emerged as valuable biomarkers in septic shock, offering potential utility in diagnosis, risk stratification, treatment monitoring, and prediction of outcomes. Continued research, validation, and integration into clinical practice are necessary to fully realize their potential in improving patient care and outcomes in septic shock.

Comparison of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio for the diagnosis of neonatal sepsis: a systematic review and meta-analysis

PURPOSE

To compare the performance of Neutrophil-to-Lymphocyte Ratio (NLR) with that of Platelet-to-Lymphocyte Ratio (PLR) in diagnosing neonatal sepsis (NS).

METHODS

PubMed and Embase were searched for relevant studies from the inception of the databases to May, 2022. The pooled sensitivity (SEN), specificity (SPE), and area under the receiver operator characteristic curve (AUC) were measured.

RESULTS

Thirteen studies involving 2610 participants were included. The SEN, SPE, and AUC of NLR were 0.76 (95%CI: 0.61-0.87), 0.82 (95%CI: 0.68-0.91), and 0.86 (95%CI: 0.83-0.89), respectively, and those of PLR were 0.82 (95%CI: 0.63-0.92), 0.80 (95%CI: 0.24-0.98), and 0.87 (95%CI: 0.83-0.89), respectively. Significant heterogeneity was observed among the studies. Subgroup analysis and meta-regression showed that types of sepsis (p = 0.01 for SEN), gold standard (p = 0.03 for SPE), and pre-set threshold (p<0.05 for SPE) might be the sources of heterogeneity for NLR, whereas the pre-set threshold (p<0.05 for SPE) might be the source of heterogeneity for PLR.

CONCLUSIONS

NLR and PLR would be of great accuracy for the diagnosis of NS, and the two indicators have similar diagnostic performance. However, the overall risk of bias was high, and significant heterogeneity was identified among the included studies. The results of this study should be interpreted prudently, and the normal or cut-off values and the type of sepsis should be considered. More prospective studies are needed to further support the clinical application of these findings.

Bronchoalveolar Lavage and Blood Markers of Infection in Critically Ill Patients-A Single Center Registry Study

Microbiological sampling is an indispensable targeted antibiotic therapy for critically ill patients. Invasive respiratory sampling by bronchoalveolar lavage (BAL) can be performed to obtain samples from the lower respiratory tract. It is debated as to whether blood markers of infection can predict the outcome of BAL in a medical intensive care unit (ICU). Retrospectively, all ICU patients undergoing BAL from 2009-2018 were included. A total of 468 BAL samples from 276 patients (average age 60 years, SAPS2 47, ICU-mortality 41.7%) were analyzed. At the time of BAL, 94.4% patients were mechanically ventilated, 92.9% had suspected pneumonia, 96.2% were on antibiotic therapy and 36.3% were immunocompromised. Relevant bacteria were cultured in 114/468 (24.4%) cases of BAL. Patients with relevant bacteria in the culture had a higher ICU mortality rate (45.6 vs. 40.4%, p = 0.33) and were significantly less likely to be on a steroid (36 vs. 52%, p < 0.01) or antimycotic (14.9 vs. 34.2%, p < 0.01), while procalcitonin (PCT), C-reactive protein (CRP), and white blood cell (WBC) counts were similar. The area under the receiver operating curve (AUC) values for positive culture and PCT, CRP and WBC counts were low (0.53, 0.54 and 0.51, respectively). In immunocompromised patients, AUC values were higher (0.65, 0.57 and 0.61, respectively). Therefore, microbiological cultures by BAL revealed relevant bacteria in 24.4% of samples. Our data, therefore, might suggest that indication for BAL should not be based on blood markers of infection.

Utility of procalcitonin as a predictor of bloodstream infections and supportive modality requirements in critically ill cancer patients

BACKGROUND

We evaluated the diagnostic utility of procalcitonin (PCT) in predicting bacterial bloodstream infections (BSI) in critically ill cancer patients with and without neutropenia. We also investigated the role of PCT as a prognostic marker of supportive modalities (vasopressors, invasive mechanical ventilation, and renal replacement therapy (RRT)) in the intensive care unit (ICU).

METHODS

We retrospectively analyzed 2200 PCT and blood cultures from adult cancer patients with suspected sepsis. Primary outcome was BSI, defined by positive blood culture, collected within 72 h of PCT collection.

RESULTS

Median PCT values were higher in encounters with BSI (3.2 vs 0.5 ng/ml, p < 0.001). The area under the ROC curve (AUC) was 0.726 (95%CI 0.698, 0.754). PCT > 2.0 ng/ml was significantly associated with greater likelihood of BSI and this effect was significantly stronger for neutropenic (OR 9.09, 95%CI: 4.39, 18.79) compared with non-neutropenic patients (OR 4.00 (95% CI: 3.13, 5.10), interaction p = 0.036). PCT > 2.0 was associated with vasopressor requirement on ICU admission (OR 1.82 (95% CI 1.31, 2.53), p < 0.001) and RRT (OR 2.20 (95% CI 1.24, 3.91), p = 0.007).

CONCLUSIONS

Procalcitonin is a fair discriminator of BSI in critically ill cancer patients with and without neutropenia and a PCT > 2.0 ng/ml was significantly more likely to require vasopressors and RRT in the ICU.

A reusable PMMA/paper hybrid plug-and-play microfluidic device for an ultrasensitive immunoassay with a wide dynamic range

Conventional colorimetric enzyme-linked immunosorbent assay (ELISA) is a time-consuming laboratory assay that is not very sensitive and consumes a large amount of samples. Herein, the development of a reusable, cost-effective, and eco-friendly poly(methyl methacrylate) (PMMA)/paper hybrid plug-and-play (PnP) device for high-sensitivity immunoassay by analyte enrichment and efficient passing-through washing has been reported. The PMMA device has multiple slots where a pre-patterned paper substrate can be inserted. The sample flows back-and-forth through a low-cost, 3D paper substrate within the PMMA channels, thereby enhancing the amount of analyte adsorbed and dramatically increasing the sensitivity while decreasing the assay time. After the enrichment assay, the paper substrate can simply be pulled out of the device, and the results can be qualitatively viewed with the naked eye or scanned through a simple desktop scanner for quantitative analysis. The paper substrate can be replaced with a new substrate so that the device can be reused. The limits of detection (LODs) of 200 pg/mL for immunoglobulin G (IgG) and 270 pg/mL for hepatitis B surface antigen (HBsAg) were obtained. This IgG assay is at least 10 times more sensitive than commercial ELISA kits. In addition, the PnP ELISA exhibited a significant increase in the linear dynamic range from 3 orders of magnitude in a common paper-based device to a wide range of six orders of magnitude in the PnP hybrid device. This reusable PnP device has great potential for the low-cost yet high-sensitivity detection of infectious diseases, cancers, and other important biomolecules.

Neutrophil-lymphocyte ratio in the early diagnosis of sepsis in an intensive care unit: a case-control study

OBJECTIVE

To evaluate the neutrophil-lymphocyte ratio as a predictor of sepsis and mortality in patients admitted to an intensive care unit.

METHODS

Case-control study of adult patients admitted to an intensive care unit. Patients who had sepsis as the reason for admission and who had a previous complete blood count examination were included as case patients. The following statistical analyses were performed: ROC curves, binary logistic regression, and Mann-Whitney and Pearson's chi-square tests. p < 0.05 was considered significant.

RESULTS

The ROC curve values were 0.62 for neutrophil-lymphocyte ratio, 0.98 for band neutrophils and 0.51 for total leukocytes. The presence of a neutrophil-lymphocyte ratio greater than 5.0, leukocyte count above 12,000mm3/mL and band neutrophil percentage above 10% were risk factors for sepsis; however, only the SAPS 3 and SOFA score were related to patient mortality.

CONCLUSION

The neutrophil-lymphocyte ratio and band neutrophils in combination with other parameters may be markers for the early detection of sepsis in intensive care units.