Comparison of Candida colonization in intensive care unit patients with and without COVID-19: First prospective cohort study from Turkey.

Candida species are the primary cause of fungal infections in intensive care units (ICUs). Despite the increasing prevalence of Candida-related infections, monitoring the progression of these infections from colonization in COVID-19 ICU patients lacks sufficient information. This study aims prospectively to compare 62 COVID-19 and 60 non-COVID-19 ICU patients from admission to discharge in terms of colonization development, rates, isolated Candida species, risk factors, and Candida infections during hospitalization. A total of 1464 samples were collected at specific time intervals from various body sites [mouth, skin (axilla), rectal, and urine]. All samples were inoculated onto CHROMagar Candida and CHROMagar Candida Plus media, and isolates identified using MALDI-TOF MS. COVID-19 patients exhibited significantly higher colonization rates in oral, rectal, and urine samples compared to non-COVID-19 patients, (p < 0.05). Among the Candida species, non-albicans Candida was more frequently detected in COVID-19 patients, particularly in oral (75.8%-25%; p < 0.001) and rectal regions (74.19% - 46.66%; p < 0.05). Colonization with mixed Candida species was also more prevalent in the oropharyngeal region (p < 0.05). Mechanical ventilation and corticosteroid use emerged as elevated risk factors among COVID-19 patients (p < 0.05). Despite the colonization prevalence, both COVID-19-positive and negative patients exhibited low incidences of Candida infections, with rates of 9.67% (n = 6/62) and 6.67% (n = 3/60), respectively. Consequently, although Candida colonization rates were higher in COVID-19 ICU patients, there was no significant difference in Candida infection development compared to the non-COVID-19 group. However, the elevated rate of non-albicans Candida isolates highlights potential future infections, particularly given their intrinsic resistance in prophylactic or empirical treatments if needed. Additionally, the high rate of mixed colonization emphasizes the importance of using chromogenic media for routine evaluation.

This is the first prospective cohort study comparing Candida colonization features including species and body sites from the time of admission to the externalization in intensive care unit patients with and without COVID-19. It provides key points that can be referenced for fungal approaches in future disasters.

Criteria for Hyperinflammation Developing in COVID-19: Analysis of 2 Cohorts From Different Periods of the Pandemic.

OBJECTIVE: Hyperinflammation (HI) that develops in week 2 of COVID-19 contributes to a worse outcome. Because week 2 laboratory findings can be relatively mild, the available criteria for classification of hemophagocytic lymphohistiocytosis or macrophage activation syndrome are not helpful. METHODS: Our study included a discovery cohort of patients from Turkey with symptomatic COVID-19 who were followed up while hospitalized during the initial wave and a replication cohort of hospitalized patients from a later period, all of whom required oxygen support and received glucocorticoids. Diagnosis of HI was made by an expert panel; most patients with COVID-19-associated HI (HIC) received tocilizumab or anakinra. Clinical and laboratory data from start day of treatment with tocilizumab or anakinra in HIC patients were compared with the data from day 5-6 in patients without HIC. Values maximizing the sensitivity and specificity of each parameter were calculated to determine criteria items. RESULTS: The discovery cohort included 685 patients, and the replication cohort included 156 patients, with 150 and 61 patients receiving treatment for HI, respectively. Mortality rate in HI patients in the discovery cohort (23.3%) was higher than the rate in patients without HI (3.7%) and the rate in patients in the overall replication cohort (10.3%). The 12-item criteria that we developed for HIC showed that a score of 35 provided 85.3% sensitivity and 81.7% specificity for identification of HIC. In the replication cohort, the same criteria resulted in 90.0% sensitivity for HIC; however, lower specificity values were observed because of the inclusion of milder cases of HIC responding only to glucocorticoids. CONCLUSION: The use of the 12-item criteria for HIC can better define patients with HIC with reasonable sensitivity and specificity and enables an earlier treatment start.

Elevated sTREM2 and NFL levels in patients with sepsis associated encephalopathy.

PURPOSE: Sepsis-associated encephalopathy (SAE) is a common manifestation of sepsis that may lead to cognitive decline. Our aim was to investigate whether the neurofilament light chain (NFL) and soluble triggering receptor expressed on myeloid cells 2 (sTREM2) could be utilized as prognostic biomarkers in SAE. MATERIALS AND METHODS: In this prospective observational study, baseline serum levels of sTREM2 and cerebrospinal fluid (CSF) levels of sTREM2 and NFL were measured by ELISA in 11 SAE patients and controls. Patients underwent daily neurological examination. Brain magnetic resonance imaging (MRI) and standard electroencephalography (EEG) were performed. Cognitive dysfunction was longitudinally assessed after discharge in 4 SAE patients using the Mini-Mental State Examination (MMSE) and Addenbrooke's Cognitive Examination-Revised (ACE-R) tests. RESULTS: SAE patients showed higher CSF sTREM2 and NFL levels than controls. sTREM2 and NFL levels were not correlated with the severity measures of sepsis. Three months after discharge, 2 SAE patients displayed ACE-R scores congruent with mild cognitive impairment (MCI), persisting in one patient 12 months after discharge. SAE patients with MCI showed higher CSF NFL levels, bacteremia, and abnormal brain MRI. Patients with increased serum/CSF sTREM2 levels showed trends towards displaying poorer attention/orientation and visuo-spatial skills. CONCLUSIONS: sTREM2 and NFL levels may serve as a prognostic biomarker for cognitive decline in SAE. These results lend further support for the involvement of glial activation and neuroaxonal degeneration in the physiopathology of SAE.

Dipyridamole does not have any additive effect on the prevention of COVID-19 coagulopathy.

OBJECTIVE: Severe acute respiratory syndrome (SARS) coronavirus 2 (SaRS-Cov-2) associated respiratory disease (COVID-19), announced as a pandemic, is a multisystem syndrome. SARS-CoV-2 directly infects and damages vascular endothelial cells, which leads to microvascular dysfunction and promotes a procoagulant state. Dipyridamole (DP) acts as a reversible phosphodiesterase inhibitor and is used mainly as an antiplatelet agent. It is hypothetised that it has possible activities in COVID-19. DESIGN AND METHODOLOGY: We report our retrospective, real-world results of DP added to low-molecular weight heparin (LMWH) in the treatment of 462 clinically diagnosed and hospitalized COVID-19 patients. We compared anticoagulation with and without DP addition with no administration of anticoagulation in the same time frame. The primary outcome was proven or highly suspected coagulopathy within 30 days of hospitalization. RESULTS: Definitive coagulopathy has been diagnosed in 3 (3.5%) of 85 LMWH administered patients and 7 (2.13%) of 328 DP + LMWH received patients (P=0.456). Five cases with definitive coagulopathy were not initiated any anticoagulation at the time of the event. The multivariate analysis showed that DP addition to the anticoagulant approach did not have any impact on the risk of demonstrated coagulopathy and highly-suspected coagulopathy. CONCLUSION: We think that our clinical experience is valuable in showing the real-life results of DP + LMWH treatment in COVID-19. This approach did not affect the coagulopathy rate. Our data did also not document an additive effect of DP in the COVID-19 outcome. Prospective controlled trials would give more convincing results regarding the role of DP in COVID-19 endothelial dysfunction and clinical outcome.

Posterior Reversible Encephalopathy in Sepsis-Associated Encephalopathy: Experience from a Single Center.

BACKGROUND: Sepsis-associated encephalopathy (SAE) is frequently encountered in sepsis and is often accompanied by neuroimaging findings indicating ischemia, hemorrhage, and edema. Posterior reversible encephalopathy syndrome (PRES) has been vastly underrecognized in previously reported cohorts of patients with sepsis and SAE. Our aim was to determine the prevalence and distinguishing clinical, neuroimaging, and electroencephalography features of PRES in SAE. METHODS: In this prospective observational study, patients with radiologically identified PRES were selected from a consecutively enrolled cohort of 156 patients with SAE and assessed for neurological outcome using the extended Glasgow Outcome Scale for 12 months. Patients with SAE and PRES and other types of brain lesions were compared in terms of clinical and diagnostic workup features. RESULTS: Fourteen of 156 patients (8.9%) were determined to be radiologically compatible with PRES, whereas 48 patients displayed other types of acute brain lesions. Patients with PRES often showed lesions in atypical regions, including frontal lobes, the corpus callosum, and the basal ganglia. Source of infection was mostly gram-negative bacteria originating from pneumonia or intraabdominal infections. Patients with PRES were not different from other patients with SAE with brain lesions in terms of features of sepsis and neurological outcome. However, patients with PRES showed increased prevalence of seizures and intraabdominal source of infection. CONCLUSIONS: PRES is highly prevalent in SAE, often encompasses unusual brain regions, and usually presents with generalized seizures. Patients with SAE and PRES do not appear to have distinguishing clinical and diagnostic workup features. However, generalized seizures may serve as warning signs for presence of PRES in patients with SAE.

Ability of short-time low peep challenge to predict fluid responsiveness in mechanically ventilated patients in the intensive care.

Short-time low PEEP challenge (SLPC, application of additional 5 cmH2O PEEP to patients for 30 s) is a novel functional hemodynamic test presented in the literature. We hypothesized that SLPC could predict fluid responsiveness better than stroke volume variation (SVV) in mechanically ventilated intensive care patients. Heart rate, mean arterial pressure, stroke volume index (SVI) and SVV were recorded before SLPC, during SLPC and before and after 500 mL fluid loading. Patients whose SVI increased more than 15% after the fluid loading were defined as fluid responders. Reciever operating characteristics (ROC) curves were generated to evaluate the abilities of the methods to predict fluid responsiveness. Fifty-five patients completed the study. Twenty-five (46%) of them were responders. Decrease percentage in SVI during SLPC (SVIΔ%-SLPC) was 11.6 ± 5.2% and 4.3 ± 2.2% in responders and non-responders, respectively (p < 0.001). A good correlation was found between SVIΔ%-SLPC and percentage change in SVI after fluid loading (r = 0.728, P < 0.001). Areas under the ROC curves (ROC-AUC) of SVIΔ%-SLPC and SVV were 0.951 (95% CI 0.857-0.991) and 0.747 (95% CI 0.611-0.854), respectively. The ROC-AUC of SVIΔ%-SLPC was significantly higher than that of SVV (p = 0.0045). The best cut-off value of SVIΔ%-SLPC was 7.5% with 90% sensitivity and 96% specificity. The percentage change in SVI during SLPC predicts fluid responsiveness in intensive care patients who are ventilated with low tidal volumes; the sensitivity and specificity values are higher than those of SVV.

[First Case of COVID-19 Positive Candida auris Fungemia in Turkey]. / Türkiye'de Ilk COVID-19 Pozitif Candida auris Fungemi Olgusu.

Candida auris is a species of fungus that has gained importance in recent years owing to its ability to cause hospital infections and epidemics, resistant to antifungal agents and disinfection processes and frequently misidentified by commercial systems. Hospital outbreaks caused by C.auris have been reported from some countries. It has been determined that C.auris has lower virulence than Candida albicans; however, it is associated with high mortality rates in immunocompromised individuals. An increase in the incidence of invasive fungal infections which can lead to serious complications and death, has been identified in severe coronavirus-2019 (COVID-19) patients or immunocompromised individuals with underlying disease. Studies demonstrated an increase in the frequency of C.auris isolation in COVID-19 patients with candidemia. In this report, the first case of COVID-19 positive C.auris fungemia detected in Turkey was presented. A 71-year-old male patient with a history of myocardial infarction, diabetes mellitus, donation of a single kidney and lobectomy surgery due to lung cancer was hospitalized in the pandemic thoracic surgery service due to the findings consistent with viral pneumonia on thoracic computed tomography. Favipiravir 2 x 600 mg and intravenous dexamethasone 1 x 6 mg therapy was administered. The patient tested positive for SARS-CoV-2 polymerase chain reaction, and severe involvement of the left lung was detected in the following days. Antibiotics were administered, followed by insertion of a right jugular vein catheter and initation of tocilizumab. The patient was transferred to the intensive care unit due to increased respiratory distress. Yeast growth was detected in the patient's hemoculture. The yeast strain could not be identified using API ID 32C (bioMerieux, France) (Sacchromyces kluyveri, Candida sake, unacceptable profile), but was identified as C.auris using the VITEK MALDI TOF MS (bioMerieux, France) (99.9%) system and confirmed by sequencing. The minimum inhibitor concentration values were detected as 3 µg/ml for amphotericin B; > 256 µg/ml for fluconazole; 0.19 µg/ml for voriconazole; 0.19 µg/ml for itraconazole; 0.016 µg/ml for posaconazole; 1 µg/ml for caspofungin and 0.094 µg/ml for anidulafungin by using the antibiotic gradient method. The patient's initial treatment comprised meropenem 3 x 1 g, vancomycin 2 x 1 g, caspofungin 1 x 70 mg, and continued as caspofungine 1 x 50 mg after the loading dose, and vancomycin 1 x 1 g/48 hours from the third day of treatment. The patient died on the ninth day after developing candidemia. The present case is the first case of fungemia caused by C.auris in a COVID-19 positive patient in Turkey, and it emphasizes the need of caution for fungemia due to C.auris in intensive care units in our country which has a high COVID-19 incidence.

Initial complete blood count score and predicting disease progression in COVID-19 patients.

INTRODUCTION: Coronavirus has caused a pandemic since it was first detected in Wuhan in December 2019. The mortality rate is high in moderate and severe cases. Our study aimed to screen the CBC parameters as a useful predictive factor for COVID-19 resulting in critical illness. METHODS: A total of 285 patients with positive PCR results were analyzed. The median age was 55 (24-90), and 64.2% of patients were male. Sixty-eight percent of cases were hospitalized with moderate, 32% with severe disease at initial admission. RESULTS: We found that lymphocyte count <620/mcl, neutrophil-to-lymphocyte ratio (NLR) >6, and platelet to lymphocyte ratio (PLR) >350 were predictive of the outcome. We scored our cohort 0-3 for these three parameters. Patients with a score of 2-3 were more likely to have progressive disease, anti-cytokine treatment, intensive care admission, intubation, and death, compared to patients with a score of 0-1. Additionally, they tended to be hospitalized for longer (median 11.5 days, mean 15.6), compared to those with a score 0 or 1 (median 9 days, mean 11.3). Twenty-eight of 38 cases with scores of 2-3 were discharged (73.6%), whereas the rate was 89% for patients with a score of 0-1 (P=0.009). CONCLUSION: Based on the absolute lymphocyte count (<620/mcl, NLR >6, PLR >350), our three-parameter score was able to predict disease progression, and the likelihood of anti-cytokine treatment, intubation, and death. We think that COVID-19 patients presenting with moderate to severe pneumonia, and having scores of 2 or 3 on our scale, should be closely monitored and robustly supported.

Prognostic Value of Antithrombin Levels in COVID-19 Patients and Impact of Fresh Frozen Plasma Treatment: A Retrospective Study

Objective: The defective interplay between coagulation and inflammation may be the leading cause of intravascular coagulation and organ dysfunction in coronavirus disease-19 (COVID-19) patients. Abnormal coagulation profiles were reported to be associated with poor outcomes. In this study, we assessed the prognostic values of antithrombin (AT) activity levels and the impact of fresh frozen plasma (FFP) treatment on outcome. Materials and Methods: Conventional coagulation parameters as well as AT activity levels and outcomes of 104 consecutive critically ill acute respiratory distress syndrome (ARDS) patients with laboratory-confirmed COVID-19 disease were retrospectively analyzed. Patients with AT activity below 75% were treated with FFP. Maximum AT activity levels achieved in those patients were recorded. Results: AT activity levels at admission were significantly lower in nonsurvivors than survivors (73% vs. 81%). The cutoff level for admission AT activity was 79% and 58% was the lowest AT for survival. The outcome in those patients who had AT activity levels above 75% after FFP treatment was better than that of the nonresponding group. As well as AT, admission values of D-dimer, C-reactive protein, and procalcitonin were coagulation and inflammatory parameters among the mortality risk factors. Conclusion: AT activity could be used as a prognostic marker for survival and organ failure in COVID-19-associated ARDS patients. AT supplementation therapy with FFP in patients with COVID-19-induced hypercoagulopathy may improve thrombosis prophylaxis and thus have an impact on survival.

Thrombotic Events Related to Extracorporeal Membrane Oxygenation in COVID-19-Associated Severe Acute Respiratory Distress Syndrome.

Hypercoagulopathy associated with the novel coronavirus disease (COVID-19) is the leading cause of acute respiratory distress syndrome (ARDS), multiple organ failure, and mortality. Extracorporeal membrane oxygenation (ECMO) has been used to manage patients with COVID 19-associated severe respiratory or cardiac failure. In this report, we aim to summarise our experience with deadly thrombotic complications during venovenous ECMO (vvECMO) treatment in 6 patients with COVID-19-associated ARDS between March 19, 2020 and April 20, 2020. Based on our experience with 6 COVID-19-associated ARDS patients on ECMO, we intend to raise awareness regarding thrombotic complications leading to mortality.

Effects of adjunct treatment with intravenous immunoglobulins on the course of severe COVID-19: results from a retrospective cohort study.

OBJECTIVES: To evaluate the effect of adjunct treatment with Octagam, an intravenous immunoglobulin (IVIG) product, on clinical outcomes and biomarkers in critically ill COVID-19 patients. METHODS: Data from a single center was analyzed retrospectively. Patients had received preliminary standard intensive care (SIC) according to a local treatment algorithm, either alone or along with IVIG 5% at 30 g/day for 5 days. The two groups were compared regarding baseline characteristics, survival and changes in inflammation markers. Imbalance in baseline APACHE II scores was addressed by propensity score matching. Otherwise, Kaplan-Meier and multiple logistic regression models were used. RESULTS: Out of 93 patients, 51 had received IVIG and 42 had not. About 75% of patients were male and both groups had comparable body mass index and AB0 blood type distribution. IVIG-treated patients were younger (mean 65 ± 15 versus 71 ± 15 years, p = .066) and had slightly lower baseline disease scores (APACHE II: 20.6 versus 22.4, p = .281; SOFA: 5.0 versus 7.0, p = .006). Overall survival was 61% in the SIC + IVIG and 38% in the SIC only group (odds ratio: 2.2, 95% confidence interval: 0.9-5.4, p = .091 after controlling for baseline imbalances). IVIG significantly prolonged median survival time (68 versus 18 days, p = .014) and significantly reduced plasma levels of C-reactive protein (median change from baseline -71.5 versus -0.3 mg/L, p = .049). CONCLUSION: Clinically relevant benefits through adjunct IVIG treatment in COVID-19 need to be confirmed in a randomized, controlled trial.

Brain Volume Changes in Patients with Acute Brain Dysfunction Due to Sepsis.

BACKGROUND: Sepsis-induced brain dysfunction (SIBD) is often encountered in sepsis patients and is related to increased morbidity. No specific tests are available for SIBD, and neuroimaging findings are often normal. In this study, our aim was to analyze the diagnostic value of volumetric analysis of the brain structures and to find out its significance as a prognostic measure. METHODS: In this prospective observational study, brain magnetic resonance imaging (MRI) sections of 25 consecutively enrolled SIBD patients (17 with encephalopathy and 8 with coma) and 22 healthy controls underwent volumetric evaluation by an automated segmentation method. RESULTS: Ten SIBD patients had normal MRI, and 15 patients showed brain lesions or atrophy. The most prominent volume reduction was found in cerebral and cerebellar white matter, cerebral cortex, hippocampus, and amygdala, whereas deep gray matter regions and cerebellar cortex were relatively less affected. SIBD patients with normal MRI showed significantly reduced volumes in hippocampus and cerebral white matter. Caudate nuclei, putamen, and thalamus showed lower volume values in non-survivor SIBD patients, and left putamen and right thalamus showed a more pronounced volume reduction in coma patients. CONCLUSIONS: Volumetric analysis of the brain appears to be a sensitive measure of volumetric changes in SIBD. Volume reduction in specific deep gray matter regions might be an indicator of unfavorable outcome.

Diagnosing acute brain dysfunction due to sepsis.

Developments in the management of critically ill patients suffering organ dysfunctions have demonstrated that brain is the prominent organ to be effected during critical illness. Acute brain dysfunction due to pathologic neuroinflammatory processes associated with sepsis is commonly seen and related to morbidity and mortality in the ICU treatment. Studies reported that survivors of sepsis may suffer long-term cognitive dysfunction that affects quality of life. However, there are no specific approaches to diagnose acute brain dysfunction in the early phase to target protective measures. In recent years, imaging methods and biomarkers are the most important issues of studies. This review will address the current diagnostic approaches to acute brain dysfunction related to sepsis.

Association Between Inflammatory Markers and Cognitive Outcome in Patients with Acute Brain Dysfunction Due to Sepsis.

INTRODUCTION: Sepsis-induced brain dysfunction (SIBD) has been neglected until recently due to the absence of specific clinical or biological markers. There is increasing evidence that sepsis may pose substantial risks for long term cognitive impairment. METHODS: To find out clinical and inflammatory factors associated with acute SIBD serum levels of cytokines, complement breakdown products and neurodegeneration markers were measured by ELISA in sera of 86 SIBD patients and 33 healthy controls. Association between these biological markers and cognitive test results was investigated. RESULTS: SIBD patients showed significantly increased IL-6, IL-8, IL-10 and C4 d levels and decreased TNF-α, IL-12, C5a and iC3b levels than healthy controls. No significant alteration was observed in neuronal loss and neurodegeneration marker [neuron specific enolase (NSE), amyloid ß, tau] levels. Increased IL-1ß, IL-6, IL-8, IL-10, TNF-α and decreased C4 d, C5a and iC3b levels were associated with septic shock, coma and mortality. Transient mild cognitive impairment was observed in 7 of 21 patients who underwent neuropsychological assessment. Cognitive dysfunction and neuronal loss were associated with increased duration of septic shock and delirium but not baseline serum levels of inflammation and neurodegeneration markers. CONCLUSION: Increased cytokine levels, decreased complement activity and increased neuronal loss are indicators of poor prognosis and adverse events in SIBD. Cognitive dysfunction and neuronal destruction in SIBD do not seem to be associated with systemic inflammation factors and Alzheimer disease-type neurodegeneration but rather with increased duration of neuronal dysfunction and enhanced exposure of the brain to sepsis-inducing pathogens.

Neuroimaging Findings in Sepsis-Induced Brain Dysfunction: Association with Clinical and Laboratory Findings.

BACKGROUND: Incidence and patterns of brain lesions of sepsis-induced brain dysfunction (SIBD) have been well defined. Our objective was to investigate the associations between neuroimaging features of SIBD patients and well-known neuroinflammation and neurodegeneration factors. METHODS: In this prospective observational study, 93 SIBD patients (45 men, 48 women; 50.6 ± 12.7 years old) were enrolled. Patients underwent a neurological examination and brain magnetic resonance imaging (MRI). Severity-of-disease scoring systems (APACHE II, SOFA, and SAPS II) and neurological outcome scoring system (GOSE) were used. Also, serum levels of a panel of mediators [IL-1ß, IL-6, IL-8, IL-10, IL-12, IL-17, IFN-γ, TNF-α, complement factor Bb, C4d, C5a, iC3b, amyloid-ß peptides, total tau, phosphorylated tau (p-tau), S100b, neuron-specific enolase] were measured by ELISA. Voxel-based morphometry (VBM) was employed to available patients for assessment of neuronal loss pattern in SIBD. RESULTS: MRI of SIBD patients were normal (n = 27, 29%) or showed brain lesions (n = 51, 54.9%) or brain atrophy (n = 15, 16.1%). VBM analysis showed neuronal loss in the insula, cingulate cortex, frontal lobe, precuneus, and thalamus. Patients with abnormal MRI findings had worse APACHE II, SOFA, GOSE scores, increased prevalence of delirium and mortality. Presence of MRI lesions was associated with reduced C5a and iC3b levels and brain atrophy was associated with increased p-tau levels. Regression analysis identified an association between C5a levels and presence of lesion on MRI and p-tau levels and the presence of atrophy on MRI. CONCLUSIONS: Neuronal loss predominantly occurs in limbic and visceral pain perception regions of SIBD patients. Complement breakdown products and p-tau stand out as adverse neuroimaging outcome markers for SIBD.

Mechanisms of action of intravenous immunoglobulin in septic encephalopathy.

Acute brain dysfunction associated with sepsis is a serious complication that results in morbidity and mortality. Intravenous immunoglobulin (IVIg) treatment is known to alleviate behavioral deficits in the experimentally induced model of sepsis. To delineate the mechanisms by which IVIg treatment prevents neuronal dysfunction, an array of immunological and apoptosis markers was investigated. Our results suggest that IVIgG and IgGAM administration ameliorates neuronal dysfunction and behavioral deficits by reducing apoptotic cell death and glial cell proliferation. IgGAM treatment might suppress classical complement pathway by reducing C5a activity and proapoptotic NF-κB and Bax expressions, thereby, inhibiting major inflammation and apoptosis cascades. Future animal model experiments performed with specific C5aR and NF-κB agonists/antagonists or C5aR-deficient mice might more robustly disclose the significance of these pathways. C5a, C5aR, and NF-κB, which were shown to be the key molecules in brain injury pathogenesis in sepsis, might also be utilized as potential targets for future treatment trials of septic encephalopathy.

Neuroprotective effects of intravenous immunoglobulin are mediated through inhibition of complement activation and apoptosis in a rat model of sepsis.

BACKGROUND: Intravenous (IV) immunoglobulin (Ig) treatment is known to alleviate behavioral deficits and increase survival in the experimentally induced model of sepsis. To delineate the mechanisms by which IVIg treatment prevents neuronal dysfunction, an array of immunological and apoptosis markers was investigated. METHODS: Sepsis was induced by cecal ligation perforation (CLP) in rats. The animals were divided into five groups: sham, control, CLP + saline, CLP + immunoglobulin G (IgG) (250 mg/kg, iv), and CLP + immunoglobulins enriched with immunoglobulin M (IgGAM) (250 mg/kg, iv). Blood and brain samples were taken in two sets of experiments to see the early (24 h) and late (10 days) effects of treatment. Total complement activity, complement 3 (C3), and soluble complement C5b-9 levels were measured in the sera of rats using ELISA-based methods. Cerebral complement, complement receptor, NF-κB, Bax, and Bcl-2 expressions were analyzed by western blot and/or RT-PCR methods. Immune cell infiltration and gliosis were examined by immunohistochemistry using CD3, CD4, CD8, CD11b, CD19, and glial fibrillary acidic protein antibodies. Apoptotic neuronal death was investigated by TUNEL staining. RESULTS: IVIgG and IgGAM administration significantly reduced systemic complement activity and cerebral C5a and C5a receptor expression. Likewise, both treatment methods reduced proapoptotic NF-κB and Bax expressions in the brain. IVIgG and IgGAM treatment induced considerable amelioration in glial cell proliferation and neuronal apoptosis which were increased in non-treated septic rats. CONCLUSIONS: We suggest that IVIgG and IgGAM administration ameliorates neuronal dysfunction and behavioral deficits by reducing apoptotic cell death and glial cell proliferation. In both treatment methods, these beneficial effects might be mediated through reduction of anaphylatoxic C5a activity and subsequent inhibition of inflammation and apoptosis pathways.

Effects of different recruitment maneuvers on bacterial translocation and ventilator- induced lung injury.

BACKGROUND: Investigated in the present study were the effects of various recruitment maneuvers (RMs) using the same inflation pressure-time product on bacterial translocation from lung to blood, and ventilator-induced lung injury (VILI). METHODS: Tracheotomy was performed on anesthetized rats, and ventilation was initiated using pressure-controlled mode. Subsequently, Pseudomonas aeruginosa was inoculated through the tracheotomy tube and ventilated for 30 minutes before rats were randomly separated into 4 groups. Group 1 underwent sustained inflation (SI), Group 2 underwent low-pressure SI, Group 3 underwent modified sigh, and Group 4 was a control group. Blood cultures were taken at baseline, 15 minutes after randomization (after each RM for the first hour), and finally at 75 minutes after the last RM. The rats were euthanized and the lungs were extirpated. The left lung was taken for measurement of wet:dry weight ratio, and the right lung was used for pathologic evaluation. RESULTS: Positive blood cultures were found to be higher in Group 3 at early study periods. Total pathological scores were also higher in Group 3. CONCLUSION: Higher severity of ventilator-induced lung injury occurred in the modified sigh group, evidenced by bacterial translocation and results of histopathological evaluation.

Effects of intravenous immunoglobulin therapy on behavior deficits and functions in sepsis model.

BACKGROUND: We aim to demonstrate behavioral alterations in a sepsis model using intravenous (IV) immunoglobulin G (IgG) and immunoglobulins enriched with IgA and IgM (IgGAM). METHODS: We divided 48 Wistar albino rats into five groups: control group, sham-operated group (only antibiotic treatment), cecal ligation and puncture (CLP) group (CLP plus antibiotic treatment), IgG group (250 mg/kg IV IgG) and IgGAM group (250 mg/kg IV IgGAM). Intravenous immunoglobulins were given 5 min after the CLP procedure. Experimental animals put into three behavioral tasks 10, 30 and 60 days after the surgery; to evaluate the locomotor activity, an open field test was performed, elevated plus maze test was used to measure anxiety levels, and depressive state was assessed by forced swimming test. The effects of therapy which were acquired from the results of these tests were used to estimate the behavioral changes after CLP. RESULTS: The mortality rate of 50% in the septic rats decreased to 30 and 20% with the administration of IgG and IgGAM, respectively. Significant changes on locomotor activity and depressive-like behavior were reported in the sepsis group; on the other hand, the treatment with immunoglobulins reduced the symptoms. Treatment with immunoglobulins attenuated the sepsis-related anxiogenic-like responses. Behavioral alterations returned to normal on day 60 in all groups. CONCLUSIONS: Sepsis caused deterioration on behavioral parameters. Immunoglobulin treatments alleviated the symptoms of functional disturbances and caused early reversal of behavioral deficits in septic animals.