Can neutrophil to lymphocyte ratio predict late-onset sepsis in preterm infants?

Biomarker for Infection in Children with Decompensated Chronic Liver Disease: Neutrophilic CD64 or Procalcitonin?

OBJECTIVE

Biomarkers with high accuracy for identification of infection in decompensated chronic liver disease (DCLD) are urgently needed. We compared the accuracy of neutrophilic cluster of differentiation 64 (nCD64) with procalcitonin for diagnosis of bacterial infection in children with DCLD.

METHODS

Consecutive children admitted with DCLD were enrolled prospectively. nCD64 was assessed by flow cytometry and expressed in percentage. nCD64, procalcitonin and hemogram were measured at admission and 7-14 days after treatment in those with infection. Complete work-up for infection was done. Presence, site and severity of infection was classified as per guidelines.

RESULTS

107 children [64 boys, age 97(18-168) months] were enrolled. 78(72.9%) had infection, 26(24%) had severe sepsis and 60(56%) had systemic inflammatory response syndrome. The commonest site of infection was ascitic fluid (n=37), followed by pneumonia (n=24), urinary tract (n=15), bacteraemia (n=10), cholangitis (n=8) and cellulitis (n=3). nCD64 (cut-off-51%, AUC-0.82) had a higher sensitivity (79.5%) and specificity (82.8%) than procalcitonin (cut-off ≥0.58ng/mL, AUC-0.74, sensitivity-76.9% and specificity-62.1%) for diagnosis of infection. nCD64 and procalcitonin correlated with infection severity, being highest in children with severe sepsis [88(71-97) %and 1.98(0.83-10.36) ng/mL], than in infection alone [72(45-84) % and 1.09(0.45-2.07) ng/mL], and no-infection [36(20.2-48) % and 0.42(0.19-1.08) ng/mL]. There was no difference in diagnostic utility of procalcitonin or nCD64 with different sites of infection. Elevation of all 3 parameters (nCD64, PCT and total leukocyte count) was uncommon but highly specific for presence of infection.

CONCLUSION

nCD64 identifies infection better than procalcitonin and correlates well with infection severity in children with DCLD.

Evaluation of systemic inflammatory indices in the diagnosis of early onset neonatal sepsis in very low birth weight infants

BACKGROUND

Previously, not six systemic inflammatory indices were evaluated in the diagnosis of early onset sepsis (EOS) in very low birth weight (VLBW, <1500g) premature infants.

OBJECTIVES

We evaluated the effectiveness of systemic inflammatory indices in the diagnosis of EOS in VLBW infants.

METHODS

Premature infants with birth weight <1500 g were included in the study. Six systemic inflammatory indices including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), pan-immune-inflammation value (PIV), and systemic inflammation response index (SIRI) were compared in patients with EOS (treatment group) and without EOS (control group).

RESULTS

Of 917 infants enrolled, 204 infants were in the EOS group and 713 infants comprised the control group. NLR, MLR and SIRI values were significantly higher in the EOS group than in the control group (p < 0.001). The AUC value of SIRI for the predictivity of EOS was 0.803.

CONCLUSIONS

The SIRI can be used together with other parameters as both an easily accessible and the reliable systemic inflammatory indices in the diagnosis of EOS in VLBW preterm infants.

Meta-analysis of the role of neutrophil to lymphocyte ratio in neonatal sepsis

INTRODUCTION

The neutrophil to lymphocyte ratio (NLR), an inflammatory biomarker, measures innate-adaptive immune system balance. In this systematic review and meta-analysis, we aim to analyze the current literature to evaluate the diagnostic role of NLR in neonatal sepsis.

METHODS

PubMed, Web of Science, and Scopus were used to conduct a systematic search for relevant publications published before May 14, 2022.

RESULTS

Thirty studies, including 2328 neonates with sepsis and 1800 neonates in the control group, were included in our meta-analysis. The results indicated that NLR is higher in neonates with sepsis compared to healthy controls (SMD = 1.81, 95% CI = 1.14-2.48, P-value < 0.001) in either prospective (SMD = 2.38, 95% CI = 1.40-3.35, P-value < 0.001) or retrospective studies (SMD = 0.87, 95% CI = 0.63-1.12, P-value < 0.001) with a pooled sensitivity of 79% (95% CI = 62-90%), and a pooled specificity of 91% (95% CI = 73-97%). Also, we found that NLR is higher in neonates with sepsis compared to those who were suspected of sepsis but eventually had negative blood cultures (SMD =1.99, 95% CI = 0.76-3.22, P-value = 0.002) with a pooled sensitivity of 0.79% (95% CI = 0.69-0.86%), and a pooled specificity of 73% (95% CI = 54-85%). In addition, neonates with sepsis had elevated levels of NLR compared to other ICU admitted neonates (SMD = 0.73, 95% CI = 0.63-0.84, P < 0.001). The pooled sensitivity was 0.65 (95% CI, 0.55-0.80), and the pooled specificity was 0.80 (95% CI, 0.68-0.88).

CONCLUSION

Our findings support NLR as a promising biomarker that can be readily integrated into clinical settings to aid in diagnosing neonatal sepsis. As evidenced by our results, restoring balance to the innate and adaptive immune system may serve as attractive therapeutic targets. Theoretically, a reduction in NLR values could be used to measure therapeutic efficacy, reflecting the restoration of balance within these systems.

Can We Estimate Late-Onset Sepsis by Serial Methemoglobin Levels? An Observational Study in Preterm Neonates

Objective: To assess serial methemoglobin (MetHb) levels in preterm infants as a possible diagnostic method for late-onset sepsis (LOS). Methods: Preterm infants were assigned into two groups: those with culture-proven LOS and controls. Serial MetHb levels were measured. Results: The MetHb values of the LOS group were found to be significantly increased (p < 0.001). The cutoff value for the detection of LOS was calculated as MetHb > 1.75%, optimized for a sensitivity of 81.9% and specificity of 90%. After antimicrobial therapy, MetHb values were found to decrease significantly (p < 0.001). MetHb had an AUC of 0.810 for mortality using the calculated cutoff of >2% (p < 0.005). Conclusions: MetHb levels increase at the onset of LOS and decrease following treatment. MetHb can be added to other sepsis biomarkers as a rapid infectious process indicator for preterm neonates. MetHb > 2% is associated with LOS mortality.

The Neutrophil-to-Lymphocyte Ratio (NLR) Can Predict Sepsis's Presence and Severity in Malnourished Infants-A Single Center Experience

Sepsis represents one of the leading causes of death in newborns and infants, and prompt diagnosis is essential for achieving favorable outcomes. Regarding malnourished children with concurrent infection, most studies have focused, besides blood culture, on C-reactive protein and procalcitonin. Because malnutrition has a deleterious effect on cellular immune competence, the present study characterized the acute-phase response, including hematological indices, in response to sepsis. Among the examined laboratory biomarkers, procalcitonin and neutrophil-to-lymphocyte ratio were the most accurate discriminators between sepsis patients and those with bacterial infection. Moreover, these two parameters showed a gradual increase between sepsis, severe sepsis, and septic shock patients (p < 0.001). Subgroup analysis of the sepsis group revealed positive correlations of NLR with prolonged ICU stay (<0.001), acute organ dysfunction (0.038), mechanical ventilation (<0.001), and fatality (<0.001). In summary, our results suggest that the neutrophil-to-lymphocyte ratio can be used as an auxiliary diagnostic index in discriminating the presence and severity of bacterial sepsis in malnourished infants.

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.

Diagnostic performance of routine blood parameters in periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome

BACKGROUND

We aimed to investigate the difference between PFAPA and streptococcal tonsillitis (Strep Pharyngitis) by using blood parameters. We want to evaluate the relationship between periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome, and tonsillitis by using NLR.

METHODS

The data of 141 pediatric patients who had applied to our clinic between October 2016 and March 2019 and were diagnosed with PFAPA syndrome and tonsillitis were reviewed from hospital records. The demographic data of the study group were recorded, as were their WBC, neutrophil, and lymphocyte counts, NLR, and MPV values, which are obtained by proportioning these two counts.

RESULTS

CRP and ESR values were significantly higher in the PFAPA group (p = 0.026 and p < 0.001, respectively). No significant difference was determined between the groups in terms of platelet count or lymphocyte count. Receiver operating curve analyses were calculated. The AUC was 0.713 ± 0.04 according to age, and the CRP was 0.607 ± 0.04 (95% confidence interval). Using a cutoff point of >49 months for age, the sensitivity was 0.71 and the specificity was 0.67.

CONCLUSION

With simple laboratory parameters, PFAPA syndrome can be differentiated from a diagnosis of tonsillitis. This may reduce the costs associated with unnecessary antibiotic use. However, these findings still need to be confirmed by other future studies.

Evaluation of Haematological Parameters and Uric Acid in the Diagnosis of Late Onset Neonatal Sepsis

Introduction A number of parameters studied in a whole blood count can be helpful in the diagnosis of neonatal sepsis. The platelet/lymphocyte ratio (PLR) is a systemic inflammatory marker in early sepsis and has been used as a diagnostic indicator in cardiovascular events and cancer. Being one of the major antioxidants in human biological fluids, serum uric acid is responsible for neutralising free radicals. The red cell distribution width/platelet ratio (RPR) is a diagnostic marker in adult inflammatory diseases. The objective of our study is to investigate the relationship of late neonatal sepsis with whole blood count parameters and serum uric acid levels. Materials and methods Newborns older than postnatal three days who had clinical and laboratory findings of sepsis were included in the study. The study included 140 newborns who were divided into three groups, 53 in the culture-proven late sepsis group, 47 in the clinical sepsis group, and 40 in the healthy control group. The whole blood count parameters and serum uric acid levels were examined in both the clinical sepsis and proven sepsis patients at the time when they were diagnosed with sepsis. Results The birth week was significantly lower in the evidenced and clinical sepsis patients compared to the healthy control group. Development of late sepsis was significantly higher in the male gender than in healthy controls. Serum uric acid levels were significantly higher in proven or clinical sepsis than in healthy controls. The level of serum uric acid (3.77±1.6) in proven sepsis was significantly higher than the control group (2.83±1.1). The uric acid level had an area under the curve (AUC) 0.552-0.717, 35% sensitivity, 95% specificity, 94.6% positive predictive value (PPV), and 36.9% negative predictive value (NPV) in the diagnosis of proven and clinical late sepsis. Neutrophil/lymphocyte ratio (NLR) was significantly higher in proven sepsis than in healthy newborns and was higher in the clinical sepsis group than in the proven sepsis group (p: 0.002). While the mean eosinophil value was 618.5±472.1 in proven sepsis, it was 549.3±294.9 in the control group and there was a statistically significant difference between the two groups (p: 0.036). Conclusion In late-onset neonatal sepsis, the NLR level was higher, and the eosinophil level was lower in the clinical sepsis patients than in healthy newborns. We believe that a higher level of serum uric acid in sepsis is effective in the early diagnosis of patients who also had other clinical findings of sepsis.

Carboxyhemoglobin Levels in Preterm Neonatal Late-Onset Sepsis: to Predict or not to Predict

Background

In this study, we aimed to evaluate carboxyhemoglobin (COHb) levels in diagnosing late-onset sepsis (LOS) in preterm neonates.

Methods

The records of culture-positive LOS in preterm neonates hospitalized in NICU from January 2017 to July 2022 were reviewed. COHb levels, C-reactive protein, procalcitonin, and neutrophil to lymphocyte ratio of septic preterm infants were compared to controls. In addition, serial COHb levels measured within six hours before or 24h after blood culture sampling, three to seven days prior, and three to five days after starting antimicrobial therapy were retrieved from patient records.

Results

The study included 77 blood-culture-positive preterm infants and 77 non-septic controls. During the LOS episode, the COHb values were found to be significantly increased (median: 1.8, IQR: 1.4-2.5) when compared to the control group (median: 1.2, IQR: 0.8-1.6) (p < 0.001). ROC analysis yielded an AUC of 0.714 for COHb (95% CI: 0.631-0.796, p<0.001). At an optimal cut-off of >1.5%, the test's sensitivity was 64.94%, the specificity was 72.73%, the positive predictive value was 70.42%, and the negative predictive value was 67.47%. LOS led to a dramatic rise followed by a decrease after the initiation of the antimicrobial therapy [1.8 (1.4-2.5)] vs. [1.45 (0.2-4)] p<0.001.

Conclusion

COHb levels increased at the beginning of LOS, decreasing in response to antibiotics. When used in conjunction with other sepsis biomarkers, the variation of COHb can be important in evaluating late-onset sepsis episodes in preterm infants.

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

OBJECTIVES

The purpose of this study was systematically and quantitatively to assess the value of the neutrophil-to-lymphocyte ratio (NLR) for the diagnosis of neonatal sepsis by systematic review and meta-analysis.

DESIGN

Systematic review and meta-analysis.

METHODS

Eight major databases, including The Cochrane, PubMed, Embase, Web of Science, CNKI, Wanfang, China Biomedical Literature Database and VIP Database, were systematically searched for NLR diagnoses of neonatal sepsis from inception to June 2022. Two investigators independently conducted the literature search, screening, data extraction and quality evaluation with the Quality Assessment of Diagnostic Accuracy Studies-2 checklist. Statistical analysis was performed using Review Manager V.5.3, Stata V.16.0, R (V.3.6.0) and Meta-DISC V.1.4.

RESULTS

A total of 14 studies comprising 1499 newborns were included in this meta-analysis. With a cut-off value ranging from 0.1 to 9.4, the pooled sensitivity of the NLR in the diagnosis of neonatal sepsis was 0.74 (95% CI: 0.61 to 0.83), the pooled specificity was 0.88 (95% CI: 0.73 to 0.95), the positive likelihood ratio (LR⁺) was 6.35 (95% CI: 2.6 to 15.47), the negative likelihood ratio (LR^-) was 0.30 (95% CI: 0.19 to 0.46), the diagnostic OR (DOR) was 12.88 (95% CI: 4.47 to 37.08), area under the curve (AUC) was 0.87 (95% CI: 0.84 to 0.89). In the subgroup analysis of early-onset neonatal sepsis, the pooled sensitivity was 0.75 (95% CI: 0.47 to 0.91), the pooled specificity was 0.99 (95% CI: 0.88 to 1.00), the LR⁺ was 63.3 (95% CI: 5.7 to 696.8), the LR^- was 0.26 (95% CI: 0.10 to 0.63), the DOR was 247 (95% CI: 16 to 3785) and the AUC was 0.97 (95% CI: 0.95 to 0.98).

CONCLUSIONS

Our findings suggest that the NLR is a helpful indicator for the diagnosis of early neonatal sepsis, but it still needs to be combined with other laboratory tests and specific clinical manifestations.

Monocyte Distribution Width in Children With Systemic Inflammatory Response: Retrospective Cohort Examining Association With Early Sepsis

OBJECTIVES

To investigate the association between increased monocyte distribution width (MDW) and pediatric sepsis in the emergency department (ED).

DESIGN

Retrospective cohort study.

SETTING

A single academic hospital study.

PATIENTS

Patients from birth to the age of 18 years who presented at the ED of an academic hospital with systemic inflammatory response syndrome (SIRS) were consecutively enrolled. Sepsis was diagnosed using the International Pediatric Surviving Sepsis Campaign criteria.

INTERVENTIONS

Antibiotic treatment was administrated once infection was suspected.

MEASUREMENTS AND MAIN RESULTS

Routine complete blood cell count, neutrophil-to-lymphocyte ratio (NLR), and MDW, a new inflammatory biomarker, were evaluated in the ED. Logistic regression models were used to explore associations with early pediatric sepsis. We included 201 patients with sepsis and 1,050 without sepsis. In the multivariable model, MDW greater than 23 U (odds ratio [OR], 4.97; 95% CI, 3.42-7.22; p < 0.0001), NLR greater than 6 (OR, 2.06; 95% CI, 1.43-2.94; p = 0.0001), WBC greater than 11,000 cells/µL (OR, 6.52; 95% CI, 4.45-9.53; p < 0.0001), and the SIRS score (OR, 3.42; 95% CI, 2.57-4.55; p < 0.0001) were associated with pediatric sepsis. In subgroup analysis, MDW greater than 23 U remained significantly associated with sepsis for children 6-12 years old (OR, 6.76; 95% CI, 2.60-17.57; p = 0.0001) and 13-18 years (OR, 17.49; 95% CI, 7.69-39.76; p = 0.0001) with an area under the receiver operating curve of 0.8-0.9.

CONCLUSIONS

MDW greater than 23 U at presentation is associated with the early diagnosis of sepsis in children greater than or equal to 6 years old. This parameter should be considered as a stratification variable in studies of pediatric sepsis.

Omega-3 Polyunsaturated Fatty Acids Supplementation Alleviate Anxiety Rather Than Depressive Symptoms Among First-Diagnosed, Drug-Naïve Major Depressive Disorder Patients: A Randomized Clinical Trial

Background

Omega-3 polyunsaturated fatty acids (n-3 PUFAs) augmentation of antidepressants has shown great potential in the prevention and treatment of major depressive disorders (MDD).

Objective

To investigate the effect of n-3 PUFAs plus venlafaxine in patients with first-diagnosed, drug-naïve depression.

Method

A total of 72 outpatients with first-diagnosed depression were recruited. The daily dose of 2.4 g/day n-3 PUFAs or placebo plus venlafaxine was used for over 12 weeks. The outcomes were assessed by the Hamilton depression scale (HAMD), Hamilton anxiety scale (HAMA), Beck depression inventory (BDI), and Self-rating anxiety scale (SAS).

Results

Both groups exhibited improvement on clinical characteristics at week 4 and week 12 compared with baseline. The rate of responders for anxiety in n-3 PUFAs group (44.44%) was significantly higher than that in placebo group (21.21%) at week 4 (χ² = 4.182, p = 0.041), while week 12 did not show a difference (χ² = 0.900, p = 0.343). The rate of responders for depression at both week 4 (χ² = 0.261, p = 0.609) and week 12 (χ² = 1.443, p = 0.230) showed no significant difference between two groups. Further analysis found that Childhood Trauma Questionnaire (CTQ) had positive correlation with HAMA (r = 0.301, p = 0.012), SAS (r = 0.246, p = 0.015), HAMD (r = 0.252, p = 0.038) and BDI (r = 0.233, p = 0.022) with Pearson correlation analysis. Social Support Rating Scale (SSRS) had negative correlation with SAS (r = -0.244, p = 0.015) and BDI (r = -0.365, p = 0.000).

Conclusion

This trial found that n-3 PUFAs supplementation in favor of venlafaxine alleviated the anxiety symptoms rather than depressive symptoms at the early stage of treatment (4 weeks) for first-diagnosed, drug-naïve depressed patients. However, the advantage disappeared in long-term treatment. Furthermore, childhood abuse and social support are closely related to the clinical and biological characteristics of depression. Both childhood trauma and lack of social support might be predictors of poor prognosis in depression.

Clinical Trial Registration

[clinicaltrials.gov], identifier [NCT03295708].

Composition of early life leukocyte populations in preterm infants with and without late-onset sepsis

BACKGROUND

Composition of leukocyte populations in the first month of life remains incompletely characterised, particularly in preterm infants who go on to develop late-onset sepsis (LOS).

AIM

To characterise and compare leukocyte populations in preterm infants with and without LOS during the first month of life.

STUDY DESIGN

Single-centre prospective observational cohort study.

PARTICIPANTS

Infants born <30 weeks gestational age (GA).

OUTCOME MEASURES

Peripheral blood samples were collected at 1, 7, 14, 21 and 28 days of life. Leukocyte populations were characterised using 5-fluorophore-6-marker flow cytometry. Absolute leukocyte counts and frequency of total CD45+ leukocytes of each population were adjusted for GA, birth weight z-scores, sex and total leukocyte count.

RESULTS

Of 119 preterm infants enrolled, 43 (36%) had confirmed or clinical LOS, with a median onset at 13 days (range 6-26). Compared to infants without LOS, the adjusted counts and frequency of neutrophils, basophils and non-cytotoxic T lymphocytes were generally lower and immature granulocytes were higher over the first month of life in infants who developed LOS. Specific time point comparisons identified lower adjusted neutrophil counts on the first day of life in those infants who developed LOS more than a week later, compared to those without LOS, albeit levels were within the normal age-adjusted range. Non-cytotoxic T lymphocyte counts and/or frequencies were lower in infants following LOS on days 21 and 28 when compared to those who did not develop LOS.

CONCLUSION

Changes in non-cytotoxic T lymphocytes occurred following LOS suggesting sepsis-induced immune suppression.

The Utility of Peripheral Blood Leucocyte Ratios as Biomarkers in Neonatal Sepsis: A Systematic Review and Meta-Analysis

BACKGROUND

Early stage diagnosis of neonatal sepsis (NS) remains a major roadblock due to non-specific symptoms and the absence of precise laboratory index tests. The full blood count is a relatively cheap, universal, and rapid diagnostic test.

METHOD

This study assessed the diagnostic accuracies of immature-to-total neutrophil ratio (ITR), immature-to-mature neutrophil ratio (IMR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) used in the diagnosis of NS. Included studies were retrieved by searching four major databases and relevant references, and reviewed based on the inclusion/exclusion criteria. Pooled sensitivities and specificities were calculated, I ² was utilized to test for heterogeneity, and the source was investigated via meta-regression analysis.

RESULTS

Finally, 38 studies passed the eligibility criteria. A total of thirty-one studies (6,221 neonates) included data on the ITR, eight studies (1,230 neonates) included data on the IMR, seven studies (751 neonates) included data on the NLR, and two studies (283 neonates) included data on the PLR. The summary sensitivity estimates with 95% confidence interval (CI) for the ITR, IMR, NLR, and PLR tests were, respectively, 0.74 (95% CI: 0.66-0.80), 0.74 (95% CI: 0.54-0.88), 0.73 (95% CI: 0.68-0.78), and 0.81 (95% CI: 0.55-1.00). The summary specificity values for the ITR, IMR, NLR, and PLR tests were 0.83 (95% CI: 0.77-0.87), 0.89 (95% CI: 0.80-0.94), 0.69 (95% CI: 0.57-0.79), and 0.93 (95% CI: 0.81-1.00), respectively. The area under the summary receiver operating characteristic curves for the ITR, IMR, and NLR tests were 0.85 (95% CI: 0.82-0.88), 0.91 (95% CI: 0.88-0.93), and 0.75 (95% CI: 0.71-0.79). The PLR could not be evaluated because only two studies included pertinent data.

CONCLUSION

The NLR test might not be sufficiently accurate in precisely diagnosing NS. The ITR and IMR tests alone can improve the accuracy of NS diagnosis, but the marked heterogeneity and the limited number of studies prevented us from reaching any definitive conclusions. Thus, further studies are warranted to validate these findings.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42021247850].

Salivary C-Reactive Protein and Mean Platelet Volume in the Diagnosis and Follow-Up of Community-Acquired Pneumonia in Infants

Background: Community-acquired pneumonia (CAP) in infants is a major cause of morbidity and mortality, especially in developing countries. Increased salivary C-reactive protein (CRP) levels have been demonstrated in neonatal pneumonia and other diseases. We investigated the applicability of CRP and mean platelet volume (MPV) in the diagnosis and follow-up of CAP in infants. Methods: This prospective observational study included 45 infants admitted for CAP. We measured serum and salivary CRP levels via ELISA, while MPV was measured using an automated blood cell counter. Results: Both salivary and serum CRP values were significantly different in the studied population between admission and follow-up (P = 0.001 and P < 0.0001, respectively). The same was observed for MPV (P < 0.0001). We found significant positive correlations between serum and salivary CRP (r = 0.652, P < 0.0001) and between serum CRP and MPV (r = 0.495, P = 0.001), as well as between salivary CRP and MPV (r = 0.439, P = 0.003). Receiver operating curve analysis showed that salivary CRP at a cutoff value of 3.2 ng/L had a sensitivity of 97.2% and specificity of 90%, while MPV at a cutoff value of 8.4 fL showed 91% sensitivity and 90% specificity. Conclusions: The present study showed that both salivary CRP and MPV are reliable diagnostic markers of CAP in infants.

Influence of Pathogen Type on Neonatal Sepsis Biomarkers

Understanding immunoregulation in newborns can help to determine the pathophysiology of neonatal sepsis and will contribute to improve the diagnosis, prognosis, and treatment and remains an urgent and unmet medical need to understand hyperinflammation or hypoinflammation associated with sepsis in newborns. This study included infants (up to 4 days old). The "sepsis" criteria was a positive blood culture. C-reactive protein demonstrates a strong dependence on the pathogen etiology. Therefore, its diagnostic odds ratio in Gram-positive bacteremia was 2.7 and the sensitivity was 45%, while Gram-negative was 15.0 and 81.8%, respectively. A neutrophil-lymphocyte ratio above 1 and thrombocytopenia below 50 ^∗ 10⁹ cells/L generally do not depend on the type of pathogen and have a specificity of 95%; however, the sensitivity of these markers is low. nCD64 demonstrated good analytical performance and was equally discriminated in both Gram (+) and Gram (-) cultures. The sensitivity was 87.5-89%, and the specificity was 65%. The HLA-DR and programmed cell death protein study found that activation-deactivation processes in systemic infection is different at points of application depending on the type of pathogen: Gram-positive infections showed various ways of activation of monocytes (by reducing suppressive signals) and lymphocytes (an increase in activation signals), and Gram-negative pathogens were most commonly involved in suppressing monocytic activation. Thus, the difference in the bacteremia model can partially explain the problems with the high variability of immunologic markers in neonatal sepsis.

Efficiency of Monocyte/High-Density Lipoprotein Cholesterol Ratio Combined With Neutrophil/Lymphocyte Ratio in Predicting 28-Day Mortality in Patients With Sepsis

Background: Sepsis can cause unpredictable harm, and early identification of risk for mortality may be conducive to clinical diagnosis. The present study proposes to assess the efficacy of the monocyte/high-density lipoprotein cholesterol ratio (MHR) combined with the neutrophil/lymphocyte ratio (NLR) on the day of admission in predictive efficacy in the 28-day mortality risk in critical patients with sepsis.

Material and Methods: We administered observational and retrospective cohort research from a single center. The correlation of the clinical variables, together with the system severity scores of APACHE II and SOFA, are displayed by correlation analysis, and a Cox regression model could be performed to screen the independent risk factors and estimate the capacity of multiple markers in predicting 28-day mortality. The receiver operating characteristic (ROC) curve served as an applied method to output cutoff values for the diagnosis and prognostic risk, and the area under the ROC curve and net reclassification improvement index (NRI), as well as integrated discrimination improvement index (IDI) were employed to assess the feasibility of multiple parameters for predictive value in 28-day mortality of septic patients.

Results: The study enrolled 274 eligible patients with sepsis. The correlation analysis indicated NLR and MHR were related to the sepsis severity. A multivariate Cox regression analysis indicated that NLR together with MHR displayed a close relation to death rate after adjusting for other potential confounders (NLR, HR = 1.404 [95% CI 1.170–1.684], P < 0.001; MHR, HR = 1.217 [95% CI 1.112–1.331], P < 0.001). The AUC of NLR, MHR, NLR_MHR was 0.827, 0.876, and 0.934, respectively. The addition on the biomarker NLR_MHR to the prediction model improved IDI by 18.5% and NRI by 37.8%.

Conclusions: Our findings suggest that NLR and MHR trend to an elevated level in non-surviving patients with sepsis. Evaluation of NLR_MHR, an independent risk factor for increased mortality, might improve the predictive efficacy for 28-day mortality risk in septic patients.

Effects of Neutrophil-to-Lymphocyte Ratio Combined With Interleukin-6 in Predicting 28-Day Mortality in Patients With Sepsis

Background

The current study aimed to evaluate the relationship between the neutrophil-to-lymphocyte ratio (NLR) combined with interleukin (IL)-6 on admission day and the 28-day mortality of septic patients.

Material and Methods

We conducted an observational retrospective study. Patients with presumed sepsis were included. We observed the correlation of studied biomarkers (NLR, IL-6, PCT, and CRP) and the severity scores (APACHE II and SOFA scores) by plotting scatter plots. The relationships of the studied biomarkers and 28-day mortality were evaluated by using Cox regression model, receiver-operating characteristic (ROC) curve, and reclassification analysis.

Results

A total of 264 patients diagnosed with sepsis were enrolled. It was revealed that IL-6 had the strongest correlation with both APACHE II and SOFA scores, followed by the NLR and PCT, and there was no obvious correlation between CRP and the illness severity. NLR and IL-6 were independent predictors of the 28-day mortality in septic patients in the Cox regression model [NLR, odds ratio 1.281 (95% CI 1.159-1.414), P < 0.001; IL-6, odds ratio 1.017 (95% CI 1.005-1.028), P=0.004]. The area under the ROC curve (AUC) of NLR, IL-6 and NLR plus IL-6 (NLR_IL-6) was 0.776, 0.849, and 0.904, respectively.

Conclusion

Our study showed that the levels of NLR and IL-6 were significantly higher in the deceased patients with sepsis. NLR and IL-6 appeared to be independent predictors of 28-day mortality in septic patients. Moreover, NLR combined with IL-6 could dramatically enhance the prediction value of 28-day mortality.

The Association of Inflammatory Biomarker of Neutrophil-to-Lymphocyte Ratio with Spontaneous Preterm Delivery: A Systematic Review and Meta-analysis

BACKGROUND

Neutrophil-to-lymphocyte ratio (NLR), as an inflammatory biomarker, has been investigated in several studies for early prediction of preterm delivery. However, their findings seem to be controversial. Thus, this systematic review and meta-analysis was conducted to evaluate the role of NLR in predicting preterm delivery as compared to term controls.

METHODS

PubMed, Web of Science, Embase, Scopus, and Google Scholar were systematically searched from inception up to December 2020. Interstudy heterogeneity was assessed using Cochrane's Q test and the I 2 statistic. The random-effects model was employed to pool the weighted mean differences (WMDs) and the corresponding 95% confidence intervals (CIs).

RESULTS

Out of a total of 4369 recodes, fifteen articles including 3327 participants were enrolled. The meta-analysis finding using the random-effects model produced a pooled estimate suggesting a significantly higher NLR (WMD = 1.23, 95% CI: 0.40-2.07) in women with preterm delivery (P = 0.01). We found significant heterogeneity across the included studies (P < 0.001, I 2 = 92.33%). However, interstudy heterogeneity exists mainly due to differences in the definition of preterm delivery (I 2 = 0.0%). In the metaregression analysis, there was no significant effect of publication year (B = -0.288, P = 0.088), total sample size (B = -0.002, P = 0.276), and the mean age of cases (B = -0.06, P = 0.692) on the association between NLR and preterm delivery.

CONCLUSION

The results of this meta-analysis revealed that the NLR value is higher in patients with preterm delivery. The NLR could be a useful biomarker for predicting preterm delivery; however, further prospective case-control studies are required to produce stronger evidence.

The Utility of the Neutrophil-Lymphocyte Ratio as an Early Diagnostic Marker in Neonatal Sepsis

Aim To find the diagnostic utility of the neutrophil to lymphocyte ratio (NLR) in the early diagnosis of neonatal sepsis. Methodology The case records of all blood culture-positive septic neonates admitted from January 2018 to December 2018 were reviewed. Total leucocyte count, absolute neutrophil count, absolute lymphocyte counts, NLR, and C-reactive protein (CRP) of septic neonates were compared with gestational age-matched nonseptic neonates by an unpaired t-test. The diagnostic performance of NLR and CRP was analyzed by receiver operating characteristic (ROC) analysis. Result A total of 41 blood culture-positive neonates and 52 nonseptic neonates were enrolled in this study. There was no significant difference in the total leucocyte count and absolute neutrophil counts of septic and nonseptic neonates. The mean absolute lymphocyte count of septic neonates (2795±1424/cumm) was significantly lower than that of nonseptic neonates (4449±1794/cumm; p=<0.001). The mean NLR of septic neonates (3.88±1.78) was significantly higher as compared to nonseptic (2.3404 ±1.98) neonates (p=0.045). For the diagnosis of sepsis, NLR at cutoff >1.7 had a sensitivity and specificity of 68.3% and 46.2%, respectively; CRP at cutoff >6 mg/dl had sensitivity and specificity of 78.05% and 92.31%, respectively. In the ROC analysis, the area under the curve (AUC) for CRP and NLR for the diagnosis of neonatal sepsis was 0.918 (p=<0.001) and 0.623 (p=0.042), respectively. Conclusion Blood culture-positive septic neonates had significantly higher NLR as compared to nonseptic neonates. However, when compared to CRP, NLR was not found to be a better predictor of sepsis in our study.

Neutrophil-to-Lymphocyte Ratio as an Alternative Marker of Neonatal Sepsis in Developing Countries

Objectives

We sought to analyze the neutrophil-to-lymphocyte ratio (NLR) as an alternative marker of neonatal sepsis.

Methods

In this cross-sectional study, we undertook consecutive sampling in all inborn neonates admitted to the Neonatal Intensive Care Unit with clinical manifestations of neonatal sepsis. Neonates with congenital anomalies and referred neonates were excluded. Complete blood count, C-reactive protein (CRP), and blood culture were carried out as the septic workup examinations based on the local Clinical Practical Guidelines. NLR is obtained by dividing the absolute count of neutrophils from lymphocytes manually. A cut-off value of NLR is obtained using a receiver operating characteristic curve.

Results

The median NLR value of the 104 neonates who met the inclusion and exclusion criteria was 3.63 (2.39–6.12). Neonates with NLR of 2.12 have the area under the curve of 0.630 (95% confidence interval (CI): 0.528–0.741) and 0.725 (95% CI: 0.636–0.814) when combined with CRP = 2.70 mg/dL. Neonates with NLR ≥ 2.12 in clinical neotnatal sepsis had almost double the risk of providing positive blood culture results (relative risk = 1.867, 95% CI: 1.077–3.235; p = 0.011).

Conclusions

NLR, calculated from complete blood count, can be used as an alternative marker of easy and relatively inexpensive neonatal sepsis, especially in developing countries, and detection of proven neonatal sepsis to be better when combined with CRP.

Predictors of serious bacterial infections using serum biomarkers in an infant population aged 0 to 90 days: a prospective cohort study

OBJECTIVE

Young febrile infants represent a vulnerable population at risk for serious bacterial infections (SBI). We aimed to evaluate the diagnostic accuracy of components of the complete blood count in comparison with C-reactive protein (CRP) to predict SBI among febrile infants.

DESIGN AND SETTING

Prospective cohort study conducted in a tertiary emergency department between December 2018 and November 2019.

PATIENTS

We included febrile infants ≤3 months old with complete blood count results. We analysed their white blood cell count (WBC), absolute neutrophil ratio (ANC), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio, mean platelet volume to platelet count ratio, and compared these to the performance of CRP.

MAIN OUTCOME MEASURES

SBIs were defined as urinary tract infection, bacteraemia, bacterial meningitis, sepsis, pneumonia, skin and soft tissue infection, bacterial enteritis, septic arthritis or osteomyelitis.

RESULTS

Of the 187 infants analysed, 54 (28.9%) were diagnosed with SBI. Median values of WBC, ANC, NLR and CRP were significantly higher in infants with SBI: WBC (13.8 vs 11.4×10⁹/L, p=0.004), ANC (6.7 vs 4.1×10⁹/L, p<0.001), NLR (1.3 vs 0.9, p=0.001) and CRP (21.0 vs 2.3 mg/L, p<0.001), compared with those without. CRP had the best discriminatory values for SBI, with area under the curve (AUC) of 0.815 (95% CI 0.747 to 0.883), compared with WBC, ANC and NLR. A predictive model consisting of WBC, ANC and NLR in combination with clinical parameters, had an AUC of 0.814 (95% CI 0.746 to 0.883). There was increased discriminative performance when this predictive model was combined with CRP, (AUC of 0.844, 95% CI 0.782 to 0.906).

CONCLUSION

In young febrile infants, CRP was the best discriminatory biomarker for SBI. WBC, ANC and NLR when used in combination have potential diagnostic utility in this population.

Antibiotic Discontinuation 24 h After Neonatal Late-Onset Sepsis Work-Up-A Validated Decision Tree Model

Objectives: Neonatal late-onset sepsis work-up is a frequent occurrence in every neonatal department. Blood cultures are the diagnostic gold standard, however, a negative culture prior to 48-72 h is often considered insufficient to exclude sepsis. We aimed to develop a decision tree which would enable exclusion of late-onset sepsis within 24 h using clinical and laboratory variables. Study Design: Infants evaluated for late-onset sepsis during the years 2016-2019, without major malformations, in a tertiary neonatal center were eligible for inclusion. Blood cultures and clinical and laboratory data were extracted at 0 and 24 h after sepsis work-up. Infants with bacteriologically confirmed late-onset sepsis were compared to matched control infants. Univariate logistic regression identified potential risk factors. A decision tree based on Chi-square automatic interaction detection methodology was developed and validated. Results: The study cohort was divided to a development cohort (105 patients) and a validation cohort (60 patients). At 24 h after initial evaluation, the best variables to identify sepsis were C-reactive protein > 0.75 mg/dl, neutrophil-to-lymphocyte ratio > 1.5 and sick-appearance at 24 h. Use of these 3 variables together with blood culture status at 24 h, enabled identification of all infants that eventually developed sepsis through the decision tree model. Our decision tree has an area under the receiver operating characteristic curve of 0.94 (95% CI: 0.90-0.98). Conclusions: In non-sick appearing infants with a negative blood culture at 24 h and normal laboratory values, sepsis is highly unlikely and discontinuing antibiotics after 24 h is a viable option.

Association of Neutrophil-Lymphocyte Ratio and the Presence of Neonatal Sepsis

The neutrophil–lymphocyte ratio (NLR) is an emerging risk factor of sepsis that is receiving increasing attention. However, the relationship between NLR and the presence of sepsis in neonates is poorly studied. Here, we retrospectively recruited 1480 neonates and collected and analyzed relevant clinical and laboratory data. According to the International Pediatric Sepsis Consensus, 737 neonates were diagnosed with sepsis, and 555 neonates were suspected for having infection. Neonates with hyperbilirubinemia (n = 188) served as controls. Neonates with sepsis had significantly elevated neutrophil counts and NLR (P < 0.001). The proportion of neonates with sepsis increased significantly from 41.6% when NLR < 0.91 to 66.2% when NLR > 1.88 group (P < 0.001). Multiple logistic regression analysis showed that NLR was an independent risk factor for the presence of neonatal sepsis. Receiver operating characteristic (ROC) curve analysis showed that the optimal cut-off value NLR for predicting the presence of neonatal sepsis was 1.62 (area under curve (AUC) = 0.63, 95% CI 0.60–0.66, P < 0.001). In conclusion, our data suggest that elevated NLR levels are associated with a higher neonatal sepsis risk.

Can we improve early identification of neonatal late-onset sepsis? A validated prediction model

OBJECTIVE

No single test can accurately identify neonatal late-onset sepsis (LOS). Our aim was to use clinical evaluation with laboratory tests to rapidly assess sepsis risk.

STUDY DESIGN

A retrospective case-control study was performed in a tertiary Neonatal Center during the years 2016-2019. Infants with bacteriologically confirmed LOS were compared with control infants. A clinical health evaluation score was assigned to each infant. A prediction model was developed and validated by multivariable analysis.

RESULTS

The study included 145 infants, 48 with sepsis, and 97 controls. LOS was independently associated with: sick appearance (OR: 5.7, 95% CI: 1.1-29.1), C-reactive protein > 0.75 (OR: 5.4, 95% CI: 1.1-26.3), and neutrophil-to-lymphocyte ratio > 1.5 (OR: 6.7, 95% CI: 1.2-38.5). Our model had an area under the receiver operating characteristic curve of 0.92 (95% CI: 0.86-0.97).

CONCLUSIONS

Clinical evaluation with neutrophil-to-lymphocyte ratio and C-reactive protein can rapidly identify LOS enabling decreased health costs and antibiotic use.

Agomelatine could prevent brain and cerebellum injury against LPS-induced neuroinflammation in rats

Sepsis, systemic hyper-inflammatory immune response, causes the increase of morbidity and mortality rates due to multi-organ diseases such as neurotoxicity. Lipopolysaccharide (LPS) induces inflammation, oxidative stress and apoptosis to cause brain damage. We aimed to evaluate the antioxidant, anti-inflammatory and antiapoptotic effects of Agomelatine (AGM) on LPS induced brain damage via NF-kB signaling. Twenty-four animals were divided into three groups as control, LPS (5 mg/kg) and LPS + AGM (20 mg/kg). Six hours after the all administrations, rats were sacrificed, brain tissues were collected for biochemical, histopathological and immunohistochemical analysis. In LPS group; total oxidant status (TOS), OSI index, Caspase-8 (Cas-8), NF-kß levels increased and Total antioxidant status (TAS) levels decreased biochemically and Cas-8, haptoglobin and IL-10 expressions increased and sirtuin-1 (SIRT-1) levels decreased immunohistochemically. AGM treatment reversed these parameters except haptoglobin levels in hippocampus and SIRT-1 levels in cerebellum. Besides, AGM treatment blocked the phosphorylation of NF-kB biochemically and ameliorated increased the levels of hyperemia, edema and degenerative changes histopathologically. In conclusion, AGM enhanced SIRT-1 levels to negatively regulate the transcription and activation of p-NF-kB/p65 which caused to ameliorate inflammation, oxidative stress and apoptosis.

Nonviral infection-related lymphocytopenia for the prediction of adult sepsis and its persistence indicates a higher mortality

Sepsis is a life-threatening disease that affects 30 million people worldwide each year. Despite the rapid advances in medical technology and organ support systems, it is still difficult to reduce the mortality rate. Early and rapid diagnosis is crucial to improve the treatment outcome. The aim of this study was to investigate the prediction efficiency of lymphopenia and other clinical markers, such as white blood cell (WBC), neutrophil count (N#), procalcitonin (PCT), and arterial lactic acid (Lac) in the diagnosis and prognosis assessment for adult patients with nonviral infection-related sepsis.A total of 77 sepsis- and 23 non-sepsis adult patients were enrolled in this study from September 2016 to September 2018. Daily lymphocyte count (Lym) of the patients was calculated until discharge or death. The diagnostic performance of the Lym and other biomarkers were compared using the area under the receiver operating characteristic curve (ROC) value.The level of Lym was decreased significantly in the sepsis group. Lym had a high diagnostic performance for sepsis, with an area under the curve (AUC) value of 0.971 (95% CI = 0.916-0.994). The diagnostic efficacy of Lym was more significant than WBC, N#, and PCT (P < .001). The results showed that the 28-day mortality rate of patients with continuous Lym <0.76 × 10/L was 39.66%, which significantly higher than patients without persistent lymphocytopenia.Lym is a promising, low cost, fast, and easily available biomarker for the diagnosis of sepsis. When nonviral infection is suspected and lymphocytopenia level is lower than the optimal cut-off (0.76 × 10/L) value, high vigilance is required for sepsis. The persistence with the lymphocytopenia cut-off value (<0.76 × 10/L) >3 days indicates a higher 28-day mortality rate.

Early Blood Biomarkers to Improve Sepsis/Bacteremia Diagnostics in Pediatric Emergency Settings

Background: Sepsis is the leading cause of death in children worldwide. Early recognition and treatment are essential for preventing progression to lethal outcomes. CRP and Complete Blood Count (CBC) are the initial preferred tests to distinguish between bacterial and viral infections. Specific early diagnostic markers are still missing. Aim: To investigate diagnostic value of Neutrophil-Lymphocyte Ratio (NLR), Mean Platelet Volume (MPV) and Platelet-MPV ratio (PLT/MPV) to distinguish sepsis/bacteremia and viral infection. Methods: We conducted a retrospective data analysis of case records of 115 children from 1 month to 5 years of age. All cases were divided into two groups-sepsis/bacteremia (n = 68) and viral (n = 47) patients, and further subdivided according to the time of arrival into early or late (≤12 or 12-48 h post the onset of fever, respectively). Analysis of CBC and CRP results was performed. NLR and PLT/MPV were calculated. Results: Sepsis/bacteremia group demonstrated higher absolute platelets count (370.15 ± 134.65 × 10⁸/L versus 288.91 ± 107.14 × 10⁸/L; p = 0.001), NLR (2.69 ± 2.03 versus 1.83 ± 1.70; p = 0.006), and PLT/MPV (41.42 ± 15.86 versus 33.45 ± 17.97; p = 0.001). PLT/MPV was increased in early arrival sepsis/bacteremia infants (42.70 ± 8.57 versus 31.01 ± 8.21; p = 0.008). NLR and MPV were significantly lower in infants (≤12 months) with viral infection on late arrival (1.16 ± 1.06 versus 1.90 ± 1.25, p = 0.025 for NLR and 8.94 ± 0.95fl versus 9.44 ± 0.85fl, p = 0.046 for MPV). Conclusion: Together with standard blood biomarkers, such as CRP, neutrophils, or platelets count, PLT/MPV is a promising biomarker for clinical practice to help discriminate between viral disease or sepsis/bacteremia in all children, especially in early onset of symptoms. NLR and MPV could support exclusion of sepsis/bacteremia in late arrival cases.

Utility of serum resistin in the diagnosis of neonatal sepsis and prediction of disease severity in term and late preterm infants

Introduction Resistin is a proinflammatory hormone recently proposed as a sepsis biomarker. Our aim was to evaluate the diagnostic and prognostic values of this marker in neonatal sepsis. Methods This is a prospective observational study that includes 60 term and late preterm neonates with proven and possible sepsis besides 30 healthy controls. Resistin and other biomarkers, like C-reactive protein (CRP), were measured within 2 h of neonatal intensive care unit (NICU) admission. Infants were monitored and the primary outcome was 30-day mortality. Results Resistin was higher among septic neonates compared with controls (P<0.001). Resistin had an area under the receiver operating characteristic (ROC) curve of 0.994 for differentiating septic infants from controls. The area under the curve (AUC) for differentiating infants with culture-proven sepsis from controls was 0.999 compared with an AUC of 1 for CRP. The other markers, like platelet count, were inferior to resistin and CRP. Resistin was positively correlated with CRP [Spearman's correlation coefficient (rs)=0.55, P<0.001]. No significant differences in resistin levels were noted between survivors and non-survivors but resistin was higher among infants with severe sepsis (P=0.015) and among those who needed mechanical ventilation (P<0.001). Conclusion Resistin is useful for the diagnosis of neonatal sepsis. Resistin failed to predict mortality but was associated with indicators of disease severity.

Lower neutrophil-to-lymphocyte ratio predicts high risk of multidrug-resistant Pseudomonas aeruginosa infection in patients with hospital-acquired pneumonia

Background and purpose

Hospital-acquired pneumonia (HAP) remains an important cause of morbidity and mortality despite advances in antimicrobial therapy. The emergence of multidrug resistant (MDR) Pseudomonas aeruginosa (PA) is of major concern. Our aim was to evaluate the risk factors and prognosis of HAP due to MDR-PA infection.

Patients and methods

In a retrospective observational study, we collected data on all episodes of HAP caused by PA (PA-HAP) occurring from January 2013 to December 2016. Characteristics of patients with drug-sensitive PA were compared with those with MDR-PA. Data of demographic, underlying conditions, peripheral neutrophil-to-lymphocyte ratio (NLR), and clinical outcomes were collected and analyzed.

Results

One hundred fifty-seven patients with PA-HAP were included, of which 69 (43.9%) patients were diagnosed with MDR-PA infection. There were significant differences between MDR-PA group and non-MDR-PA group on the following variables: initial inappropriate antibiotic therapy (P<0.001, OR 0.103, 95% CI 0.044–0.244), admission in more than two departments in previous 30 days (P<0.001, OR 0.186, 95% CI 0.072–0.476), and NLR level (P=0.020, OR 0.911, 95% CI 0.843–0.985). The effect of antibiotic treatment was significantly different (P<0.001, OR 4.263, 95% CI 2.142–8.483). The 30-day mortality was higher in MDR-PA group than that in non-MDR-PA group (P<0.001).

Conclusion

We have shown that lower NLR level was identified as a clinical predictor of MDR-PA infection in HAP patients. Even with goal-directed therapy, MDR-PA infection implicates poor outcomes in patients with HPA.