The impact of diabetes on the pathogenesis of sepsis

Glycemic control with insulin attenuates sepsis-associated encephalopathy by inhibiting glial activation via the suppression of the nuclear factor kappa B and mitogen-activated protein kinase signaling pathways in septic rats

Sepsis-associated encephalopathy (SAE) is frequently encountered in critically ill patients. Hyperglycemia is a common phenomenon among patients with sepsis, and glycemic control improves patient outcomes. Therefore, here, we aimed to explore whether glycemic control using insulin inhibits the pro-inflammatory cytokine response and glial activation in the cerebrum and is concomitantly associated with the relief of SAE. Using cecal ligation and puncture (CLP), sepsis was induced in male Sprague-Dawley rats. The CLP rats were administered intravenous glucose or subjected to subcutaneous insulin implant within the first hour after CLP. The survival rate, blood glucose (BG) values, and behavioral expression were assessed daily for 5 days after CLP. At day 5 after CLP, electroencephalography (EEG) recordings and blood-brain barrier (BBB) permeability testing were performed. Immunohistochemistry, immunoblotting, and enzyme-linked immunosorbent assays were used to evaluate glial activation and the pro-inflammatory cytokine response qualitatively and quantitatively, respectively. The glucose-treated CLP rats (BG > 390 mg/dL) exhibited a decline in survival rate; insensitivity to mechanical and thermal stimuli; slowed EEG activity; and an increase in BBB permeability, pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) levels, and glial activation (astrocytes and microglia) in the cerebral tissues compared with CLP rats (BG ~ 270 mg/dL). Double-immunofluorescence showed that activated astrocytes and microglia co-expressed phosphorylated nuclear factor kappa B and mitogen-activated protein kinases, respectively. Furthermore, glycemic control using insulin therapy maintained the BG at 120-160 mg/dL and inhibited the production of pro-inflammatory cytokines and glial activation in the cerebrum of septic rats. In addition, the survival rate, sensory threshold, EEG activity, and BBB permeability recovered to near-normal levels in septic rats after insulin therapy. Taken together, the results of this study elucidated the pathophysiological alterations in brains subjected to sepsis, especially regarding glycemic control. These findings improve our understanding of SAE and support the importance of glycemic control in sepsis.

The Association of Premorbid Metformin Exposure With Mortality and Organ Dysfunction in Sepsis: A Systematic Review and Meta-Analysis

Supplemental Digital Content is available in the text.

To examine the association between premorbid metformin exposure and mortality, hyperlactatemia, and organ dysfunction in sepsis.

The double burden of diabetes and global infection in low and middle-income countries

Four out of five people in the world with diabetes now live in low- and middle-income countries (LMIC), and the incidence of diabetes is accelerating in poorer communities. Diabetes increases susceptibility to infection and worsens outcomes for some of the world’s major infectious diseases such as tuberculosis, melioidosis and dengue, but the relationship between diabetes and many neglected tropical diseases is yet to be accurately characterised. There is some evidence that chronic viral infections such as hepatitis B and HIV may predispose to the development of type 2 diabetes by chronic inflammatory and immunometabolic mechanisms. Helminth infections such as schistosomiasis may be protective against the development of diabetes, and this finding opens up new territory for discovery of novel therapeutics for the prevention and treatment of diabetes. A greater understanding of the impact of diabetes on risks and outcomes for infections causing significant diseases in LMIC is essential in order to develop vaccines and therapies for the growing number of people with diabetes at risk of infection, and to prioritise research agendas, public health interventions and policy. This review seeks to give an overview of the current international diabetes burden, the evidence for interactions between diabetes and infection, immune mechanisms for the interaction, and potential interventions to tackle the dual burden of diabetes and infection.

Prostaglandin E2-Mediated Impairment of Innate Immune Response to A(H1N1)pdm09 Infection in Diet-Induced Obese Mice Could Be Restored by Paracetamol

BACKGROUND

Obesity is associated with increased severity of influenza infection. However, the underlying mechanism is largely unknown.

METHODS

We employed a mouse model with diet-induced obesity (DIO) to study the innate immune responses induced by influenza virus.

RESULTS

The lungs of DIO mice were heavily affected by obesity-associated chronic systemic inflammation with a significant increase in inflammatory cytokines/chemokines. Concurrently, lipid immune mediator prostaglandin E2 (PGE2) was also significantly elevated in DIO mice. However, the DIO mice mounted a blunted and delayed upregulation of mRNA and protein concentrations of interferon-β and inflammatory cytokines/chemokines upon A(H1N1)pdm09 virus (H1N1/415742Md) challenge compared with those of lean mice. PGE2 concentrations were significantly higher in the lungs of DIO mice compared to that of lean mice postchallenge. Treatment with paracetamol in challenged DIO mice significantly enhanced the expression of interferon-α/β and cytokine genes at days 1 and 3 postinfection compared with that of untreated DIO mice. Furthermore, paracetamol treatment alone started 3 days before virus challenge and continued until 6 days postchallenge ameliorated the severity of a lethal H1N1/415742Md infection in DIO mice with improved survival.

CONCLUSIONS

Impaired innate response to influenza in DIO mice is associated with elevated PGE2, which could be restored to some degree by paracetamol treatment.

A case of invasive pulmonary aspergillosis diagnosed by transbronchial lung biopsy during treatment for diabetic ketoacidosis in a type 1 diabetic patient

Invasive pulmonary aspergillosis (IPA) patients with non-hematological malignancy are far less than with hematological malignancy patients. We encountered a very rare case of IPA in which type 1 diabetes was the only conceivable risk factor. Further, according to the diagnostic categories of the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group (EORTC/MSG) criteria for IPA, the frequency of proven diagnosis is very low. Here we report a proven IPA, which rapidly developed when the patient with type 1 diabetes was being treated for diabetic ketoacidosis, which was successfully treated with the combination therapy of voriconazole (VRCZ) and micafungin (MCFG), based on early diagnosis using bronchoscopy.

Quantitative Proteomics Reveals Differences in the Response of Neutrophils Isolated from Healthy or Diabetic Subjects to Infection with Capsule-Variant Burkholderia thailandensis

In Thailand, diabetes mellitus is the most significant risk factor for melioidosis, a severe disease caused by Burkholderia pseudomallei. In this study, neutrophils isolated from healthy or diabetic subjects were infected with B. thailandensis E555, a variant strain with a B. pseudomallei-like capsular polysaccharide used here as a surrogate micro-organism for B. pseudomallei. At 2 h post-infection, neutrophil proteins were subjected to 4-plex iTRAQ-based comparative proteomic analysis. A total of 341 proteins were identified in two or more samples, of which several proteins involved in oxidative stress and inflammation were enriched in infected diabetic neutrophils. We validated this finding by demonstrating that infected diabetic neutrophils generated significantly elevated levels of pro-inflammatory cytokines TNFα, IL-6, IL-1β, and IL-17 compared to healthy neutrophils. Our data also revealed that infected neutrophils from healthy or diabetic individuals undergo apoptotic cell death at distinctly different rates, with infected diabetic neutrophils showing a diminished ability to delay apoptosis and an increased likelihood of undergoing a lytic form of cell death, compared to infected neutrophils from healthy individuals. Increased expression of inflammatory proteins by infected neutrophils could contribute to the increased susceptibility to infection and inflammation in diabetic patients in melioidosis-endemic areas.

Characteristics and Outcomes of Patients With and Without Type 2 Diabetes Mellitus and Pulmonary Sepsis

PURPOSE

To date, studies have provided conflicting results regarding the impact of type 2 diabetes mellitus (DM) on sepsis-related outcomes. Our objective is to understand the impact of type 2 DM in bacterial pneumonia and sepsis-related intensive care unit (ICU) outcomes.

METHODS

Retrospective study using Multiparameter Intelligent Monitoring in Intensive Care III database. We included 1698 unique patients admitted with sepsis secondary to bacterial pneumonia to the ICU within the time period of 2001 to 2012.

RESULTS

The type 2 DM group had an increased incidence of acute kidney injury (67.9% vs 58.1%, P < .01) and need for dialysis compared to the non-DM group. There was no difference in mortality, microbiology, other organ failure, or hospital length of stay between the type 2 DM and non-DM group. Lower admission blood glucose was associated with increased mortality in patients with type 2 DM (49% at ≤120 mg/dL, 35.1% at 121-180 mg/dL, and 32.1% at >180 mg/dL) but not in non-DM patients. Conversely, higher mean glucose during the hospital stay was associated with increased mortality in non-DM patients (24.7% at ≤120 mg/dL, 45.1% at 121-180 mg/dL, and 73.0% at >180 mg/dL) but not in patients with type 2 DM.

CONCLUSIONS

Our findings demonstrated that type 2 DM does not increase the overall mortality. Our findings of increased mortality in both type 2 DM patients with lower admission glucose, and non-DM patients with higher mean glucose during the hospital stay needs to be further evaluated. Future studies in regards to this could lead to personalized glucose treatment goals for patients.

Part I: Minimum Quality Threshold in Preclinical Sepsis Studies (MQTiPSS) for Study Design and Humane Modeling Endpoints

Preclinical animal studies are mandatory before new treatments can be tested in clinical trials. However, their use in developing new therapies for sepsis has been controversial because of limitations of the models and inconsistencies with the clinical conditions. In consideration of the revised definition for clinical sepsis and septic shock (Sepsis-3), a Wiggers-Bernard Conference was held in Vienna in May 2017 to propose standardized guidelines on preclinical sepsis modeling. The participants conducted a literature review of 260 most highly cited scientific articles on sepsis models published between 2003 and 2012. The review showed, for example, that mice were used in 79% and euthanasia criteria were defined in 9% of the studies. Part I of this report details the recommendations for study design and humane modeling endpoints that should be addressed in sepsis models. The first recommendation is that survival follow-up should reflect the clinical time course of the infectious agent used in the sepsis model. Furthermore, it is recommended that therapeutic interventions should be initiated after the septic insult replicating clinical care. To define an unbiased and reproducible association between a new treatment and outcome, a randomization and blinding of treatments as well as inclusion of all methodological details in scientific publications is essential. In all preclinical sepsis studies, the high standards of animal welfare must be implemented. Therefore, development and validation of specific criteria for monitoring pain and distress, and euthanasia of septic animals, as well as the use of analgesics are recommended. A set of four considerations is also proposed to enhance translation potential of sepsis models. Relevant biological variables and comorbidities should be included in the study design and sepsis modeling should be extended to mammalian species other than rodents. In addition, the need for source control (in case of a defined infection focus) should be considered. These recommendations and considerations are proposed as "best practices" for animal models of sepsis that should be implemented.

Inflammasomes: Pandora's box for sepsis

Sepsis was known to ancient Greeks since the time of great physician Hippocrates (460-377 BC) without exact information regarding its pathogenesis. With time and medical advances, it is now considered as a condition associated with organ dysfunction occurring in the presence of systemic infection as a result of dysregulation of the immune response. Still with this advancement, we are struggling for the development of target-based therapeutic approach for the management of sepsis. The advancement in understanding the immune system and its working has led to novel discoveries in the last 50 years, including different pattern recognition receptors. Inflammasomes are also part of these novel discoveries in the field of immunology which are <20 years old in terms of their first identification. They serve as important cytosolic pattern recognition receptors required for recognizing cytosolic pathogens, and their pathogen-associated molecular patterns play an important role in the pathogenesis of sepsis. The activation of both canonical and non-canonical inflammasome signaling pathways is involved in mounting a proinflammatory immune response via regulating the generation of IL-1β, IL-18, IL-33 cytokines and pyroptosis. In addition to pathogens and their pathogen-associated molecular patterns, death/damage-associated molecular patterns and other proinflammatory molecules involved in the pathogenesis of sepsis affect inflammasomes and vice versa. Thus, the present review is mainly focused on the inflammasomes, their role in the regulation of immune response associated with sepsis, and their targeting as a novel therapeutic approach.

Antimicrobial susceptibility pattern of aerobes in diabetic foot ulcers in a South-Indian tertiary care hospital

PURPOSE

Diabetic foot infections (DFIs) are major public health concerns. In the view of the ever increasing burden of multidrug-resistant (MDR) organisms, improving the use of antimicrobial agents (AMAs) is a national priority. Objective of the study was to determine antimicrobial susceptibility (AMS) pattern of aerobes in DFIs.

METHODS

A cross-sectional study was conducted for a period of 3 years at Department of Surgery, Kasturba hospital, Manipal, India during which, 260 diabetic foot ulcer (DFU) patients admitted in the general surgery wards were enrolled for the study. These patients' culture specimens were observed as Gram-stained smears and cultured aerobically on blood agar and MacConkey agar plates. AMS test was performed by disc diffusion technique according to Clinical and Laboratory Standards Institute (CLSI) guidelines.

RESULTS

A total of 354 microbes were isolated from the ulcer wounds of 213 diabetic foot patients, with an average of 1.7 organisms per lesion. Monomicrobial infections were less common (n=81; 31.2%) than polymicrobial infections (n=132; 50.7%). Gram-negative bacteria were the most common among the isolates (n=192; 54.2%). Aerobic Gram-positive Cocci accounted for 162 (45.8%) of all isolates. On the other hand, Staphylococcus aureus was the most frequently isolated aerobe (n=106; 29.9%) followed by Pseudomonas aeruginosa (n=91; 25.7%).

CONCLUSION

AMS data from our study recommends that doxycycline would be the appropriate choice as single drug for empirical coverage for Gram-positive organisms. The most appropriate antibiotic for Gram-negative organisms is meropenem. One of the critical observations is the presence of Acinetobacter, an MDR isolated from DFIs, which is either relatively or totally resistant to all the AMAs tested.

Meta-analysis of peritoneal lavage in appendicectomy

Background

The use of peritoneal lavage to prevent postoperative intra‐abdominal abscess (IAA) after appendicectomy has been debated widely.

Methods

A systematic review and meta‐analysis of suction alone versus lavage for appendicitis was performed to determine the relative benefit of lavage. Primary outcomes were postoperative IAA and wound infection (WI). Inclusion criteria were human studies reporting a comparison of appendicectomy with or without peritoneal lavage.

Results

Eight studies met the inclusion criteria, the majority of which were retrospective. Only three were RCTs. Four studies included analysis only of the paediatric population. The rate of IAA was 1·0–19·5 per cent in patients receiving suction alone and 1·5–18·6 per cent in those having lavage. WI rates were 1·0–29·2 per cent for suction alone and 0·8–20·5 per cent for lavage. The pooled risk difference for IAA was 0·01 (95 per cent c.i. −0·03 to 0·06; P = 0·50) and that for WI was 0·00 (−0·05 to 0·05; P = 0·98). Analyses of both outcomes indicated a medium degree of heterogeneity between effect estimates with I² values of 71 per cent (P = 0·001) and 70 per cent (P = 0·010) for IAA and WI respectively.

Conclusion

There is no evidence of benefit of lavage over suction for postoperative infective complications, and no individual study demonstrated a significant benefit in patients receiving lavage.

The diabetes pandemic and associated infections: suggestions for clinical microbiology

There are 425 million people with diabetes mellitus in the world. By 2045, this figure will grow to over 600 million. Diabetes mellitus is classified among noncommunicable diseases. Evidence points to a key role of microbes in diabetes mellitus, both as infectious agents associated with the diabetic status and as possible causative factors of diabetes mellitus. This review takes into account the different forms of diabetes mellitus, the genetic determinants that predispose to type 1 and type 2 diabetes mellitus (especially those with possible immunologic impact), the immune dysfunctions that have been documented in diabetes mellitus. Common infections occurring more frequently in diabetic vs. nondiabetic individuals are reviewed. Infectious agents that are suspected of playing an etiologic/triggering role in diabetes mellitus are presented, with emphasis on enteroviruses, the hygiene hypothesis, and the environment. Among biological agents possibly linked to diabetes mellitus, the gut microbiome, hepatitis C virus, and prion-like protein aggregates are discussed. Finally, preventive vaccines recommended in the management of diabetic patients are considered, including the bacillus calmette-Guerin vaccine that is being tested for type 1 diabetes mellitus. Evidence supports the notion that attenuation of immune defenses (both congenital and secondary to metabolic disturbances as well as to microangiopathy and neuropathy) makes diabetic people more prone to certain infections. Attentive microbiologic monitoring of diabetic patients is thus recommendable. As genetic predisposition cannot be changed, research needs to identify the biological agents that may have an etiologic role in diabetes mellitus, and to envisage curative and preventive ways to limit the diabetes pandemic.

Characteristics and Outcomes of Liver Transplantation for Primary Biliary Cholangitis in Young Patients: Analysis of the United Network for Organ Sharing Database

BACKGROUND

Primary biliary cholangitis (PBC) in younger patients has been suggested to require liver transplantation (LT) in early adulthood, but data is limited on its outcomes. We aimed to evaluate the characteristics and outcome of LT in young patients with PBC in comparison with older adults.

METHODS

The United Network for Organ Sharing database was analyzed for all patients with PBC who underwent LT between 2000 and 2012. Based on age at the time of LT, subjects were divided into 2 groups: young patients (≤40 y) and older adults (≥41 y). Baseline demographics, clinical parameters, and outcomes of LT were then compared between the 2 groups. Univariable and multivariable analyses were performed to assess the factors associated with outcomes of LT.

RESULTS

A total of 2084 patients with PBC were included in the analysis with 158 young patients. Compared with older adults, younger patients were more likely to be male (27.2% versus 15.4%) and nonwhite (43.7% versus 21.5%), but they were less likely to have obesity, diabetes, or hypertension (P < 0.05) and had a lower mortality (8.2% versus 15.1%) but higher retransplantation rate (14.6% versus 4.7%) (P < 0.001). On multivariable analysis, older age, dialysis or ventilator use, and lower albumin were associated with high post-LT mortality.

CONCLUSIONS

Compared with older adults, early-onset PBC in younger patients requiring LT had higher percentage of males and nonwhites and had a lower prevalence of metabolic comorbidities but higher retransplantation rates. Further studies are warranted to confirm these findings.

Pathogenicity Induced by Invasive Infection of Streptococcus dysgalactiae subsp. equisimilis in a Mouse Model of Diabetes

Streptococcus dysgalactiae subsp. equisimilis (SDSE) causes severe invasive diseases such as streptococcal toxic shock syndrome, similar to that caused by S. pyogenes (GAS). Invasive SDSE infections are increasing, particularly among patients with diabetes mellitus. Here we investigate the association between the pathogenicity of SDSE and diabetes mellitus in a mouse model, using GAS infection for comparison. Intraperitoneal injection of highly hemolytic SDSE-167 into C57BL6/J mice induced a rapid rise in blood glucose concentrations within 4 h, which was otherwise seen only in mice injected with high doses of hypervirulent GAS mutants. The survival rates of mice injected with SDSE-167 were significantly lower in mice (db/db) with type 2 diabetes than in nondiabetic mice. Injection of db/db mice with SDSE-167 increased the concentrations of cytokines and chemokines, particularly those of interleukin 6 and monocyte chemotactic protein-1. Microarray data indicate that multiple pathways are involved in the pathogenicity of SDSE-167 in db/db mice. These data reveal that the mechanisms underlying streptococcal infection differ between SDSE and GAS.

Glibenclamide Reduces Primary Human Monocyte Functions Against Tuberculosis Infection by Enhancing M2 Polarization

Tuberculosis (TB) is a global public health problem, which is caused by Mycobacterium tuberculosis (Mtb). Type 2 diabetes mellitus (T2DM) is one of the leading predisposing factors for development of TB after HIV/AIDS. Glibenclamide is a widely used anti-diabetic drug in low and middle-income countries where the incidence of TB is very high. In a human macrophage cell line, glibenclamide, a K⁺ATP-channel blocker, promoted alternative activation of macrophages by enhancing expression of the M2 marker CD206 during M2 polarization. M2 macrophages are considered poorly microbicidal and associated with TB susceptibility. Here, we investigated the effect of glibenclamide on M1 and M2 phenotypes of primary human monocytes and further determined whether specific drug treatment for T2DM individuals influences the antibacterial function of monocytes in response to mycobacterial infection. We found that glibenclamide significantly reduced M1 (HLA-DR⁺ and CD86⁺) surface markers and TNF-α production on primary human monocytes against mycobacterial infection. In contrast, M2 (CD163⁺ and CD206⁺) surface markers and IL-10 production were enhanced by pretreatment with glibenclamide. Additionally, reduction of bactericidal activity also occurred when primary human monocytes from T2DM individuals who were being treated with glibenclamide were infected with Mtb in vitro, consistent with the cytokine responses. We conclude that glibenclamide reduces M1 and promotes M2 polarization leading to impaired bactericidal ability of primary human monocytes of T2DM individuals in response to Mtb and may lead to increased susceptibility of T2DM individuals to TB and other bacterial infectious diseases.

Trends in cause-specific mortality among adults with and without diagnosed diabetes in the USA: an epidemiological analysis of linked national survey and vital statistics data

BACKGROUND

Large reductions in diabetes complications have altered diabetes-related morbidity in the USA. It is unclear whether similar trends have occurred in causes of death.

METHODS

Using data from the National Health Interview Survey Linked Mortality files from 1985 to 2015, we estimated age-specific death rates and proportional mortality from all causes, vascular causes, cancers, and non-vascular, non-cancer causes among US adults by diabetes status.

FINDINGS

From 1988-94, to 2010-15, all-cause death rates declined by 20% every 10 years among US adults with diabetes (from 23·1 [95% CI 20·1-26·0] to 15·2 [14·6-15·8] per 1000 person-years), while death from vascular causes decreased 32% every 10 years (from 11·0 [9·2-12·2] to 5·2 [4·8-5·6] per 1000 person-years), deaths from cancers decreased 16% every 10 years (from 4·4 [3·2-5·5] to 3·0 [2·8-3·3] per 1000 person-years), and the rate of non-vascular, non-cancer deaths declined by 8% every 10 years (from 7·7 [6·3-9·2] to 7·1 [6·6-7·5]). Death rates also declined significantly among people without diagnosed diabetes for all four major mortality categories. However, the declines in death rates were significantly greater among people with diabetes for all-causes (p_interaction<0·0001), vascular causes (p_interaction=0·0214), and non-vascular, non-cancer causes (p_interation<0·0001), as differences in all-cause and vascular disease death between people with and without diabetes were reduced by about a half. Among people with diabetes, all-cause mortality rates declined most in men and adults aged 65-74 years of age, and there was no decline in death rates among adults aged 20-44 years. The different magnitude of changes in cause-specific mortality led to large changes in the proportional mortality. The proportion of total deaths among adults with diabetes from vascular causes declined from 47·8% (95% CI 38·9-58·8) in 1988-94 to 34·1% (31·4-37·1) in 2010-15; this decline was offset by large increases in the proportion of deaths from non-vascular, non-cancer causes, from 33·5% (26·7-42·1) to 46·5% (43·3-50·0). The proportion of deaths caused by cancer was relatively stable over time, ranging from 16% to 20%.

INTERPRETATION

Declining rates of vascular disease mortality are leading to a diversification of forms of diabetes-related mortality with implications for clinical management, prevention, and disease monitoring.

FUNDING

None.

Positive Bacteriological Analyses in Individuals With Diabetes Mellitus: Preliminary Results From a Forensic Study

Increased infection susceptibility in the diabetic population is a controversial issue in the clinical field. The greater frequency of infections in diabetic patients has been speculated as caused by the hyperglycemic environment that favors immune dysfunction. The aim of this study was to investigate the proportion of positive bacterial cultures in a series of diabetic individuals who underwent forensic investigations and assess the frequency of hyperglycemia at the time of death in these cases as well as the percentage of diabetics with cause of death due to bacterial infection. Forensic autopsy cases characterized by positive bacterial cultures and pre-existing diagnosis of diabetes mellitus were included in the study. Initial findings revealed that 12% (7/58 cases) of positive bacterial cultures concerned individuals with a pre-existing diagnosis of diabetes mellitus. Bacterial infection was considered to be the cause of death in 22% (7/31 cases) of diabetics with positive bacterial cultures. Hyperglycemia could be identified in 1 case only at the time of death. These preliminary results highlight the usefulness of systematically performing postmortem bacteriology in the forensic setting to more precisely characterize infectious risk factors in diabetics.

The Central Role of the Inflammatory Response in Understanding the Heterogeneity of Sepsis-3

In sepsis-3, in contrast with sepsis-1, the definition "systemic inflammatory response" has been replaced with "dysregulated host response", and "systemic inflammatory response syndrome" (SIRS) has been replaced with "sequential organ failure assessment" (SOFA). Although the definition of sepsis has changed, the debate regarding its nature is ongoing. What are the fundamental processes controlling sepsis-induced inflammation, immunosuppression, or organ failure? In this review, we discuss the heterogeneity of sepsis-3 and address the central role of inflammation in the pathogenesis of sepsis. An unbalanced pro- and anti-inflammatory response, inflammatory resolution disorder, and persistent inflammation play important roles in the acute and/or chronic phases of sepsis. Moreover, powerful links exist between inflammation and other host responses (such as the neuroendocrine response, coagulation, and immunosuppression). We suggest that a comprehensive evaluation of the role of the inflammatory response will improve our understanding of the heterogeneity of sepsis.

Impact of insulin on the intestinal microcirculation in a model of sepsis-related hyperglycemia

BACKGROUND

Sepsis involves dysfunctional glucose metabolism. Among patients with sepsis, hyperglycemia is frequent and insulin administration has been evaluated for glycemic control to improve patient outcomes. Only few studies have examined the hyperglycemic microcirculation and the impact of insulin on the microvasculature in sepsis.

OBJECTIVE

To study the functional capillary density (FCD) and leukocyte activation within the intestinal microcirculation in endotoxin-induced experimental sepsis.

METHODS

In 50 male Lewis rats, endotoxemia was induced with lipopolysaccharide (LPS; 5 mg/kg). Low dose (LD) glucose was administered to avoid insulin-induced hypoglycemia. High dose (HD) glucose was administered to model sepsis-related hyperglycemia. Animals in LD and HD glucose groups received an insulin bolus (1.4 IU/kg). Two hours after LPS administration, intravital microscopy (IVM) of the terminal ileum was performed, and FCD and leukocyte adherence were measured in a blinded fashion. Blood glucose levels were measured every 30 min following the onset of endotoxemia. Plasma samples were collected 3 h after the onset of endotoxemia to measure IFN-γ, TNF-α, IL-1α, IL-4, GM-CSF and MCP-1 levels using multiplex bead immunoassay.

RESULTS

Endotoxemia significantly reduced FCD and increased leukocyte adherence within the intestinal microvasculature. LD and HD glucose administration combined with insulin improved the FCD and decreased the adherence of leukocytes in endotoxemic animals as did HD glucose administration alone. Consistent with these results, IL-4, IL-1α, GM-CSF and IFN-γ levels were decreased following combined HD glucose and insulin administration in endotoxemic animals.

CONCLUSIONS

Insulin administration, as well as an endogenous insulin response triggered by HD glucose administration, improved the FCD and decreased leukocyte activation in endotoxemic rats. The results of this study give insight into the immune and vaso-modulatory role of insulin administration during experimental endotoxemia, and may be extrapolated for clinical sepsis and other critical illnesses with marked microcirculatory dysfunction.

Utility of glycated hemoglobin screening in patients undergoing elective coronary artery surgery: Prospective, cohort study from the E-CABG registry

BACKGROUND

Patients with increased glycated hemoglobin (HbA1c) seem to be at increased risk of sternal wound infection (SWI) after coronary artery bypass grafting (CABG). However, it is unclear whether increased baseline HbA1c levels may affect other postoperative outcomes.

MATERIAL AND METHODS

Data on preoperative levels of HbA1c were collected from 2606 patients undergoing elective isolated CABG from 2015 to 2016 and included in the prospective, multicenter E-CABG registry.

RESULTS

The prevalence of HbA1c ≥ 53 mmol/mol (7.0%) among non-diabetics was 5.3%, among non-insulin dependent diabetics was 53.5% and among insulin dependent diabetics was 67.1% (p < 0.001). The prevalence of HbA1c > 75 mmol/mol (9.0%) among non-diabetics was 0.5%, among non-insulin dependent diabetics was 5.8% and among insulin dependent diabetics was 10.6% (p < 0.001). Baseline levels of HbA1c ≥ 53 mmol/mol (7.0%) was a significant predictor of any SWI (10.7% vs. 3.3%, adjusted p-value: <0.001), deep SWI/mediastinitis (3.8% vs. 1.3%, adjusted p-value: 0.001) and acute kidney injury (27.4% vs. 19.8%, adjusted p-value: 0.042). These findings were confirmed in multilevel mixed effect logistic regression adjusted for participating centers. Among patients with diabetes, HbA1c ≥ 53 mmol/mol (7.0%) was predictive of SWI (11.1% vs. 4.8%, p = 0.001).

CONCLUSIONS

HbA1c is increased in a significant proportion of patients undergoing elective CABG and these patients are at higher risk of SWI. Less clear is the impact of increased HbA1c on other postoperative outcomes. These results do not support screening of HbA1c in patients without history of diabetes. Preoperative screening of HbA1c is valuable only to identify diabetics at risk of SWI.

Adhesion and invasion attributes of Burkholderia pseudomallei are dependent on airway surface liquid and glucose concentrations in lung epithelial cells

Physiological constituents in airway surface liquids (ASL) appear to impact the adherence and invasion potentials of Burkholderia pseudomallei contributing to recrudescent melioidosis. Here, we investigated the factors present in ASL that is likely to influence bacterial adhesion and invasion leading to improved understanding of bacterial pathogenesis. Six B. pseudomallei clinical isolates from different origins were used to investigate the ability of the bacteria to adhere and invade A549 human lung epithelial cells using a system that mimics the physiological ASL with different pH, NaCl, KCl, CaCl₂ and glucose concentrations. These parameters resulted in markedly differential adherence and invasion abilities of B. pseudomallei to the lung epithelial cells. The concentration of 20 mM glucose dramatically increased adherence and invasion by increasing the rate of pili formation in depiliated bacteria. Glucose significantly increased adherence and invasion of B. pseudomallei to A549 cells, and presence of NaCl, KCl and CaCl₂ markedly ablated the effect despite the presence of glucose. Our data established a link between glucose, enhanced adhesion and invasion potentials of B. pseudomallei, hinting increased susceptibility of individuals with diabetes mellitus to clinical melioidosis.

Immune Control of Burkholderia pseudomallei--Common, High-Frequency T-Cell Responses to a Broad Repertoire of Immunoprevalent Epitopes

Burkholderia pseudomallei (Bp) is an environmental bacterial pathogen that causes potentially lethal sepsis in susceptible individuals and is considered a Category B, Tier-1 biothreat agent. As such, it is crucial to gain an improved understanding of protective immunity and potential vaccine candidates. The nature of immune correlates dictating why most exposed individuals in endemic regions undergo asymptomatic seroconversion while others succumb to life-threatening sepsis is largely uncharted. Bp seroreactive, immunogenic proteins have previously been identified by antigen microarray. We here set out to conduct an analysis of T-cell recognition of the Bp immunome using serodominant antigens represented in the original antigen microarray, examining immune correlates of disease in healthy seropositive individuals and those with acute disease or in convalescence. By screening a library of 739 overlapping peptides representing the sequences of 20 different Bp antigens, we aimed to define immune correlates of protection at the level of immunoprevalent T-cell epitopes. Responses to a large number of epitopes were common in healthy seropositive individuals: we found remarkably broad responsiveness to Bp epitopes, with 235 of 739 peptides recognized by ≥80% of all tested donors. The cumulative response to Bp epitopes in healthy, seropositive, donors from this endemic region were of the order of thousands of spot forming cells per million cells, making Bp recognition a significant component of the T-cell repertoire. Noteworthy among our findings, analysis revealed 10 highly immunoprevalent T-cell epitopes, able to induce Bp-specific IFNγ responses that were high in responding T-cell frequency within the repertoire, and also common across individuals with different human leukocyte antigen types. Acute melioidosis patients showed poor T-cell responses to the immunoprevalent epitopes, but acquired responsiveness following recovery from infection. Our findings suggest that a large repertoire of CD4 T cells, high in frequency and with broad coverage of antigens and epitopes, is important in controlling Bp infection. This offers an attractive potential strategy for subunit or epitope-based vaccines.

Multi-centre prospective internal and external evaluation of the Brompton Harefield Infection Score (BHIS)

BACKGROUND

Previously, we reported that the Brompton Harefield Infection Score (BHIS) accurately predicts surgical site infection (SSI) after coronary artery bypass grafting (CABG). The BHIS was developed using two-centre data and stratifies SSI risk into three groups based on female gender, diabetes or HbA1c > 7.5%, body mass index ≥ 35, left ventricular ejection fraction < 45% and emergency surgery. The purpose of this study was to prospectively evaluate BHIS internally as well as externally.

METHODS

Multi-centre prospective evaluation involving three tertiary centres took place between October 2012 and November 2015. SSI was classified using the Public Health England protocol. Receiver operating characteristic (ROC) curves assessed predictive accuracy.

RESULTS

Across the four hospital sites, 168 of 4308 (3.9%) CABG patients had a SSI. Categorising the hospitals by BHIS score revealed that 65% of all patients were low risk (BHIS 0-1), 26% were medium risk (BHIS 2-3) and 8% were high risk (BHIS ≥ 4). The area under the ROC curve was in the range of 0.702-0.785. Overall area under the ROC curve was 0.709.

CONCLUSIONS

BHIS provides a novel, internally and externally evaluated score for a patient's risk of SSI after CABG. It enables clinicians to focus on strategies to prospectively identify high-risk patients and improve outcomes.

Diabetes Mellitus and Sepsis: A Challenging Association

Sepsis is a life-threatening organ dysfunction caused by a deregulated host response to infection. This inappropriate response to micro-organism invasion is characterized by an overwhelmed systemic inflammatory response and cardiovascular collapse that culminate in high mortality and morbidity in critical care units. The occurrence of sepsis in diabetes mellitus (DM) patients has become more frequent, as the prevalence of DM has increased dramatically worldwide. These two important diseases represent a global public health concern and highlight the importance of increasing our knowledge of the key elements of the immune response related to both conditions. In this context, it is well established that the cells taking part in the innate and adaptive immune responses in diabetic patients have compromised function. These altered responses favor micro-organism growth, a process that contributes to sepsis progression. The present review provides an update on the characteristics of the immune system in diabetic and septic subjects. We also explore the beneficial effects of insulin on the immune response in a glycemic control-dependent and independent manner.

Melioidosis

Burkholderia pseudomallei is a Gram-negative environmental bacterium and the aetiological agent of melioidosis, a life-threatening infection that is estimated to account for ∼89,000 deaths per year worldwide. Diabetes mellitus is a major risk factor for melioidosis, and the global diabetes pandemic could increase the number of fatalities caused by melioidosis. Melioidosis is endemic across tropical areas, especially in southeast Asia and northern Australia. Disease manifestations can range from acute septicaemia to chronic infection, as the facultative intracellular lifestyle and virulence factors of B. pseudomallei promote survival and persistence of the pathogen within a broad range of cells, and the bacteria can manipulate the host's immune responses and signalling pathways to escape surveillance. The majority of patients present with sepsis, but specific clinical presentations and their severity vary depending on the route of bacterial entry (skin penetration, inhalation or ingestion), host immune function and bacterial strain and load. Diagnosis is based on clinical and epidemiological features as well as bacterial culture. Treatment requires long-term intravenous and oral antibiotic courses. Delays in treatment due to difficulties in clinical recognition and laboratory diagnosis often lead to poor outcomes and mortality can exceed 40% in some regions. Research into B. pseudomallei is increasing, owing to the biothreat potential of this pathogen and increasing awareness of the disease and its burden; however, better diagnostic tests are needed to improve early confirmation of diagnosis, which would enable better therapeutic efficacy and survival.

Review: The relationship of hemoglobin A1c to postoperative surgical risk with an emphasis on joint replacement surgery

Patients with diabetes mellitus are known to have a high risk of postoperative complications, including infections, impaired wound healing, cardiovascular events, venous thromboembolism, and mortality. Because hyperglycemia has been thought to mediate this risk, there is a clinical propensity for improving glycemic control, as assessed by hemoglobin A1c (HbA1c) level, prior to proceeding with elective surgery, particularly joint replacement surgery. However, it is not established whether chronic poor glycemic control, indicated by elevated HbA1c levels, predicts increased risk of postoperative complications. The benefit of improving glycemic control must be weighed against risks of delaying necessary elective surgery, such as joint replacement surgery, which risks may include negative impact on long-term glycemic control. Thus, we review the current evidence to determine the relationship between HbA1c and postoperative surgical risk, especially on joint replacement surgery.

A multi-center prospective study randomizing the use of fat emulsion in intensive glucose control after allogeneic hematopoietic stem cell transplantation using a myeloablative conditioning regimen

BACKGROUND & AIMS

Although parenteral nutrition (PN) is often used after allogeneic hematopoietic stem cell transplantation (allo-HSCT), there is controversy regarding PN management, for instance in the use of fat emulsion and glucose control (GC). To clarify these issues, we conducted a multi-center prospective study with intensive GC, randomizing the use of fat emulsion after allo-HSCT using a myeloablative conditioning regimen.

METHODS

The primary endpoint was the cumulative incidence of documented infectious disease, namely bacterial and fungal infection, at day 100 after allo-HSCT. Between August 2007 and March 2012, we enrolled 81 patients at 5 centers. Excluding 5 ineligible patients, 76 patients received the protocol treatment. The target fasting glucose level was 80-110 mg/dL.

RESULTS

The median follow-up of surviving patients was 1796 days. The cumulative incidences of documented infectious disease at day 100 were 16% (95% confidence interval [CI] 6-29%) in the no-fat group and 19% (95% CI 8-32%) in the fat group, indicating no significant difference. The mean glucose level at 28 days after allo-HSCT was 107 mg/dL in the no-fat group and 111 mg/dL in the fat group. Grade 3 hyperglycemia (>250 mg/dL) and grade 3 hypoglycemia (<40 mg/dL) occurred in 4 patients each (5.3%). Overall survival and non-relapse mortality rates at 4 years were 75% and 11% in the no-fat group and 69% and 8% in the fat group, respectively.

CONCLUSIONS

Irrespective of the use of fat emulsion, the long-term clinical outcomes of the enrolled patients were favorable under intensive GC. To further clarify the benefits of GC after allo-HSCT, a prospective study randomizing the level of GC is warranted.

Diabetes Is Not Associated With Increased 90-Day Mortality Risk in Critically Ill Patients With Sepsis

OBJECTIVES

To determine the association of pre-existing diabetes, hyperglycemia, and hypoglycemia during the first 24 hours of ICU admissions with 90-day mortality in patients with sepsis admitted to the ICU.

DESIGN

We used mixed effects logistic regression to analyze the association of diabetes, hyperglycemia, and hypoglycemia with 90-day mortality (n = 128,222).

SETTING

All ICUs in the Netherlands between January 2009 and 2014 that participated in the Dutch National Intensive Care Evaluation registry.

PATIENTS

All unplanned ICU admissions in patients with sepsis.

INTERVENTIONS

The association between 90-day mortality and pre-existing diabetes, hyperglycemia, and hypoglycemia, corrected for other factors, was analyzed using a generalized linear mixed effect model.

MEASUREMENTS AND MAIN RESULTS

In a multivariable analysis, diabetes was not associated with increased 90-day mortality. In diabetes patients, only severe hypoglycemia in the absence of hyperglycemia was associated with increased 90-day mortality (odds ratio, 2.95; 95% CI, 1.19-7.32), whereas in patients without pre-existing diabetes, several combinations of abnormal glucose levels were associated with increased 90-day mortality.

CONCLUSIONS

In the current retrospective large database review, diabetes was not associated with adjusted 90-day mortality risk in critically ill patients admitted with sepsis.

Infection with Burkholderia pseudomallei - immune correlates of survival in acute melioidosis

Melioidosis, caused by Burkholderia pseudomallei, is a potentially lethal infection with no licensed vaccine. There is little understanding of why some exposed individuals have no symptoms, while others rapidly progress to sepsis and death, or why diabetes confers increased susceptibility. We prospectively recruited a cohort of 183 acute melioidosis patients and 21 control subjects from Northeast Thailand and studied immune parameters in the context of survival status and the presence or absence of diabetes. HLA-B*46 (one of the commonest HLA class I alleles in SE Asia) and HLA-C*01 were associated with an increased risk of death (odds ratio 2.8 and 3.1 respectively). Transcriptomic analysis during acute infection in diabetics indicated the importance of interplay between immune pathways including those involved in antigen presentation, chemotaxis, innate and adaptive immunity and their regulation. Survival was associated with enhanced T cell immunity to nine of fifteen immunodominant antigens analysed including AhpC (BPSL2096), BopE (BPSS1525), PilO (BPSS1599), ATP binding protein (BPSS1385) and an uncharacterised protein (BPSL2520). T cell immunity to GroEL (BPSL2697) was specifically impaired in diabetic individuals. This characterization of immunity associated with survival during acute infection offers insights into correlates of protection and a foundation for design of an effective multivalent vaccine.

Lactobacillus: the not so friendly bacteria

We present a 65-year-old diabetic patient with a complex liver abscess and bacteraemia from Lactobacillus paracasei The abscess resulted in a prolonged hospital stay due to ongoing sepsis despite ultrasound-guided drainage and broad-spectrum antibiotics. Furthermore, the patient developed several secondary complications including a right-sided pleural effusion, an inferior vena cava thrombus and septic lung emboli. The abscess was eventually managed successfully with a prolonged course of antibiotics and multiple ultrasound-guided drainage procedures.To our knowledge, this is the first reported case of probiotic consumption, confirmed by strain identification, as the likely source of a liver abscess. Probiotic products have been widely used for many years and are advocated to the general public for their health benefits with no warning of side effects. Lactobacilli are one group of bacteria commonly used in these products. Although rare, complications have been reported. Susceptible patients, such as those who are immunocompromised, should be advised against excessive consumption.

Glucagon and glucagon-like peptide-1 as novel anti-inflammatory and immunomodulatory compounds

Glucagon and glucagon-like peptide-1 (GLP-1) are polypeptide hormones that are produced by pancreatic α-cells and the intestine, respectively, whose main function is to control glucose homeostasis. The glucagon and GLP-1 levels are imbalanced in diabetes. Furthermore, type 1 diabetic patients and animals present with a diminished inflammatory response, which is related to some morbidities of diabetes, such as a higher incidence of infectious diseases, including sepsis. The focus of this review is to briefly summarize the state of the art concerning the effects of glucagon and GLP-1 on the inflammatory response. Here, we propose that glucagon and GLP-1 have anti-inflammatory properties, making them possible prototypes for the design and synthesis of new compounds to treat inflammatory diseases. In addition, glucagon, GLP-1 or their analogues or new derivatives may not only be important for managing inflammatory diseases but may also have the therapeutic potential to prevent, cure or ameliorate diabetes in patients by counteracting the deleterious effects of pro-inflammatory cytokines on the function and viability of pancreatic β-cells. In addition, GLP-1, its analogues or drugs that inhibit GLP-1 metabolism may have a doubly beneficial effect in diabetic patients by inhibiting the inflammatory response and reducing glycaemia.

Prognostic factors of infective endocarditis in patients on hemodialysis: A case series from a National Multicenter Registry

BACKGROUND

Infective endocarditis (IE) is a severe complication associated with high mortality.

OBJECTIVES

To examine the clinical characteristics of IE in hemodialysis (HD) patients and to determine prognostic factors related to HD.

METHODS

From January 2008 to April 2015, 2488 consecutive patients with definite IE were included. Clinical characteristics of IE patients on HD were compared with those of IE patients who were not on HD.

RESULTS

A total of 126 patients (63% male, median age: 66years; IQR: 54-74years) with IE (5.1%) were on HD. Fifty-two patients died during hospitalization (41%) and 17 additional patients (14%) died during the first year. The rate of patients who underwent surgery during hospitalization was lower in HD patients (38 patients, 30%) than in non-HD patients (1177 patients, 50%; p<0.001). Age >70years (OR: 4.1, 95% CI: 1.7-10), heart failure (OR: 3.3, 95% CI: 1.4-7-6), central nervous system (CNS) vascular events (OR: 6.7, 95% CI: 2.1-22) and septic shock (OR: 4.1, 95% CI: 1.4-12.1) were independently associated with fatal outcome in HD patients. Of the 38 patients who underwent surgery, 15 (39.5%) died during hospitalization.

CONCLUSIONS

HD patients with IE present a high mortality. Advanced age and complications, such as heart failure, CNS stroke or septic shock, are associated with mortality.

Therapeutic potentials of Crataegus azarolus var. eu- azarolus Maire leaves and its isolated compounds

Background

Hyperglycemia is a complicated condition accompanied with high incidence of infection and dyslipidemia. This study aimed to explore the phyto-constituents of Crataegus azarolus var. eu- azarolus Maire leaves, and to evaluate the therapeutic potentials particularly antimicrobial, antihyperglycemic and antihyperlipidemic of the extract and the isolated compound (3β-O-acetyl ursolic acid).

Methods

Total phenolics and flavonoidal contents were measured by RP-HPLC analysis. Free radicals scavenging activity of different extraction solvents was tested in-vitro on DPPH free radicals. The antimicrobial activity of the ethanolic extract and its fractions as well as the isolated compounds were evaluated in-vitro on variable microorganisms. Animal models were used to evaluate the antihyperglycemic and antihyperlipidemic activities of the ethanolic extract along with the isolated compound (3β-O acetyl ursolic acid).

Results

RP- HPLC analysis of the phenolics revealed high content of rutin, salicylic and ellagic acids. Six compounds belonging to triterpenes and phenolics were isolated from chloroform and n-butanol fractions namely: ursolic acid, 3β-O-acetyl ursolic acid, ellagic acid, quercetin 3-O-β methyl ether, rutin and apigenin7-O-rutinoside. Ethanolic extract showed the highest DPPH radical scavenger activity compared to other solvents. Ethanolic extract, hexane fraction, ursolic acid, 3β-O acetyl ursolic acid and quercetin 3-O-methyl ether showed variable antimicrobial activity against E. coli, P. aeruginosa, S. aureus, and C. albicans. Administration of the ethanolic extract or 3β-O acetyl ursolic acid orally to the mice reduced blood glucose significantly in a time- and dose-dependent manner. Ethanolic extract significantly reduced LDL-C, VLDL-C, TC and TG and increased HDL-C in rats. Ethanolic extract and 3β-O acetyl ursolic acid reduced in-vitro activity of pancreatic lipase.

Conclusion

This study reveals that Crataegus azarolus var. eu- azarolus Maire has the efficiency to control hyperglycemia with its associated complications. This study is the first to evaluate antihyperglycemic and antihyperlipidemic potentials of 3β-O acetyl ursolic acid.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-017-1729-9) contains supplementary material, which is available to authorized users.

Glycaemic variability in patients with severe sepsis or septic shock admitted to an Intensive Care Unit

BACKGROUND

Sepsis is associated with morbidity and mortality, which implies high costs to the global health system. Metabolic alterations that increase glycaemia and glycaemic variability occur during sepsis.

OBJECTIVE

To verify mean body glucose levels and glycaemic variability in Intensive Care Unit (ICU) patients with severe sepsis or septic shock.

METHOD

Retrospective and exploratory study that involved collection of patients' sociodemographic and clinical data and calculation of severity scores. Glycaemia measurements helped to determine glycaemic variability through standard deviation and mean amplitude of glycaemic excursions.

RESULTS

Analysis of 116 medical charts and 6730 glycaemia measurements revealed that the majority of patients were male and aged over 60 years. Surgical treatment was the main reason for ICU admission. High blood pressure and diabetes mellitus were the most usual comorbidities. Patients that died during the ICU stay presented the highest SOFA scores and mean glycaemia; they also experienced more hypoglycaemia events. Patients with diabetes had higher mean glycaemia, evaluated through standard deviation and mean amplitude of glycaemia excursions.

CONCLUSION

Organic impairment at ICU admission may underlie glycaemic variability and lead to a less favourable outcome. High glycaemic variability in patients with diabetes indicates that monitoring of these individuals is crucial to ensure better outcomes.

Erythropoietin concentration in acute kidney injury is associated with insulin-like growth factor-binding protein-1

AIM

Erythropoietin (EPO) production is stimulated by hypoxia in the kidney. Ischaemic injury plays a crucial role in the pathogenesis of acute kidney injury (AKI). However, EPO concentrations in critically ill patients complicated with AKI have not been evaluated sufficiently. This study was conducted to clarify the factors associated with plasma EPO concentrations in AKI.

METHODS

This study prospectively enrolled 98 critically ill adult patients treated at the adult mixed ICU. Plasma EPO, insulin-like growth factor-binding protein-1 (IGFBP-1), neutrophil gelatinase-associated lipocalin (NGAL), interleukin-6 (IL-6) and urinary N-acetyl-β-D-glucosaminidase (NAG) were measured on ICU admission.

RESULTS

Acute kidney injury occurred in 42 (42.9%) patients. Significantly higher plasma EPO in the AKI group was detected than in the non-AKI group (16.13 (9.87-28.47) mIU/mL versus 27.81 (10.16-106.02) mIU/mL, P < 0.05). Plasma IGFBP-1 in the AKI group was also significantly higher than in the non-AKI group (19 208 (8820-50 780) pg/mL versus 63 199 (25 289-147 489) pg/mL, P < 0.05). Plasma EPO concentration was negatively correlated with haemoglobin in the non-AKI group with statistical significance, but not in the AKI group. Multiple logistic regression analysis revealed that plasma EPO in the AKI group was associated significantly with plasma IGFBP-1 and complication of diabetes mellitus, but not the haemoglobin concentration, partial pressure of arterial oxygen (PaO2 ), and IL-6.

CONCLUSIONS

Not low arterial oxygen tension, haemoglobin concentration, and inflammation evaluated by IL-6 but plasma IGFBP-1 was significantly associated with plasma EPO concentration in AKI, suggesting an unknown mechanism related to systemic stress conditions for EPO regulation in AKI.

Changes in blood monocyte Toll-like receptor and serum surfactant protein A reveal a pathophysiological mechanism for community-acquired pneumonia in patients with type 2 diabetes

BACKGROUND

The lung is one of the target organs of microangiopathy in diabetes mellitus (DM); patients with type 2 diabetes mellitus (T2DM) are vulnerable to pneumonia, and a variety of pathophysiological mechanisms has been described.

AIM

This study aimed to determine the pathophysiological mechanism of community-acquired pneumonia (CAP) in T2DM patients.

METHODS

A total of 90 individuals was included in this study comprised of three groups (n = 30): healthy control, T2DM and T2DM+ CAP groups. Toll-like receptor (TLR)2 and 4 protein and messenger RNA expression in peripheral blood monocytes(PBMC) was assessed by western blot and reverse transcription-polymerase chain reaction, respectively, and surfactant protein A (SP-A) levels were examined in serum samples by enzyme-linked immunosorbent assay.

RESULTS

In T2DM and T2DM+CAP groups, levels of both TLR2/4 protein and mRNA in PBMC were decreased compared with controls (P <0.05), with lower levels observed in the T2DM+CAP group in comparison with T2DM patients (P <0.05). The serum SP-A levels in T2DM+CAP individuals were significantly higher than the values obtained for T2DM patients (P <0.05). It also showed apparent increases when compared with that in controls although no statistical significance was detected.

CONCLUSION

In T2DM patients with pneumonia, TLR2/4 levels in PBMC and serum SP-A were altered, maybe playing an important role in the susceptibility to pneumonia in T2DM patients.

Glycated Hemoglobin and Risk of Sternal Wound Infection After Isolated Coronary Surgery

BACKGROUND

Glycated hemoglobin (HbA1c) is a suspected risk factor for sternal wound infection (SWI) after CABG.Methods and Results:Data on preoperative HbA1c and SWI were available in 2,130 patients undergoing isolated CABG from the prospective E-CABG registry. SWI occurred in 114 (5.4%). Baseline HbA1c was significantly higher in patients with SWI (mean, 54±17 vs. 45±13 mmol/mol, P<0.0001). This difference was also observed in patients without a diagnosis of diabetes (P=0.027), in insulin-dependent diabetic (P=0.023) and non-insulin-dependent diabetic patients (P=0.034). In the overall series, HbA1c >70 mmol/mol (NGSP units, 8.6%) was associated with the highest risk of SWI (20.6% vs. 4.6%; adjusted OR, 5.01; 95% CI: 2.47-10.15). When dichotomized according to the cut-off 53 mmol/mol (NGSP units, 7.0%) as suggested both for diagnosis and optimal glycemic control of diabetes, HbA1c was associated with increased risk of SWI in the overall series (10.6% vs. 3.9%; adjusted OR, 2.09; 95% CI: 1.24-3.52), in diabetic patients (11.7% vs. 5.1%; adjusted OR, 2.69; 95% CI: 1.38-5.25), in patients undergoing elective surgery (9.9% vs. 2.7%; adjusted OR, 2.09; 95% CI: 1.24-3.52) and in patients with bilateral mammary artery grafts (13.7% vs. 4.8%; adjusted OR, 2.35; 95% CI: 1.17-4.69).

CONCLUSIONS

Screening for HbA1c before CABG may identify untreated diabetic patients, as well as diabetic patients with suboptimal glycemic control, at high risk of SWI.

An Alteration of Lymphocytes Subpopulations and Immunoglobulins Levels in Patients with Diabetic Foot Ulcers Infected Particularly by Resistant Pathogens

The aim of our study was to analyse immune abnormalities in patients with chronic infected diabetic foot ulcers (DFUs) especially those infected by resistant microorganisms. Methods. 68 patients treated in our foot clinic for infected chronic DFUs with 34 matched diabetic controls were studied. Patients with infected DFUs were subdivided into two subgroups according to the antibiotic sensitivity of causal pathogen: subgroup S infected by sensitive (n = 50) and subgroup R by resistant pathogens (n = 18). Selected immunological markers were compared between the study groups and subgroups. Results. Patients with infected chronic DFUs had, in comparison with diabetic controls, significantly reduced percentages (p < 0.01) and total numbers of lymphocytes (p < 0.001) involving B lymphocytes (p < 0.01), CD4+ (p < 0.01), and CD8+ T cells (p < 0.01) and their naive and memory effector cells. Higher levels of IgG (p < 0.05) including IgG1 (p < 0.001) and IgG3 (p < 0.05) were found in patients with DFUs compared to diabetic controls. Serum levels of immunoglobulin subclasses IgG2 and IgG3 correlated negatively with metabolic control (p < 0.05). A trend towards an increased frequency of IgG2 deficiency was found in patients with DFUs compared to diabetic controls (22% versus 15%; NS). Subgroup R revealed lower levels of immunoglobulins, especially of IgG4 (p < 0.01) in contrast to patients infected by sensitive bacteria. The innate immunity did not differ significantly between the study groups. Conclusion. Our study showed changes mainly in the adaptive immune system represented by low levels of lymphocyte subpopulations and their memory effector cells, and also changes in humoral immunity in patients with DFUs, even those infected by resistant pathogens, in comparison with diabetic controls.

Glibenclamide impairs responses of neutrophils against Burkholderia pseudomallei by reduction of intracellular glutathione

The major risk factor for melioidosis, an infectious disease caused by B. pseudomallei, is diabetes mellitus. More than half of diabetic melioidosis patients in Thailand were prescribed glibenclamide. Recent evidence demonstrates that glibenclamide reduces pro-inflammatory cytokine production by polymorphonuclear neutrophils (PMNs) of diabetic individuals in response to this bacterial infection. However, the mechanisms by which glibenclamide affects cytokine production are unknown. We found that PMNs from glibenclamide-treated diabetic individuals infected with live B. pseudomallei in vitro showed lower free glutathione (GSH) levels compared with those of healthy individuals. Glibenclamide decreased GSH levels and glutathione peroxidase (GPx) of PMNs after exposed to live B. pseudomallei. Moreover, glibenclamide reduced cytokine production and migration capacity of infected PMNs, whereas GSH could restore these functions. Taken together, our data show a link between the effect of glibenclamide on GSH and PMN functions in response to B. pseudomallei that may contribute to the susceptibility of diabetic individuals to B. pseudomallei infection.

Differential Impact of Hyperglycemia in Critically Ill Patients: Significance in Acute Myocardial Infarction but Not in Sepsis?

Hyperglycemia is a common condition in critically ill patients admitted to an intensive care unit (ICU). These patients represent an inhomogeneous collective and hyperglycemia might need different evaluation depending on the underlying disorder. To elucidate this, we investigated and compared associations of severe hyperglycemia (>200 mg/dL) and mortality in patients admitted to an ICU for acute myocardial infarction (AMI) or sepsis as the two most frequent admission diagnoses. From 2006 to 2009, 2551 patients 69 (58-77) years; 1544 male; 337 patients suffering from type 2 diabetes (T2DM)) who were admitted because of either AMI or sepsis to an ICU in a tertiary care hospital were investigated retrospectively. Follow-up of patients was performed between May 2013 and November 2013. In a Cox regression analysis, maximum glucose concentration at the day of admission was associated with mortality in the overall cohort (HR = 1.006, 95% CI: 1.004-1.009; p < 0.001) and in patients suffering from myocardial infarction (HR = 1.101, 95% CI: 1.075-1.127; p < 0.001) but only in trend in patients admitted to an ICU for sepsis (HR = 1.030, 95% CI: 0.998-1.062; p = 0.07). Severe hyperglycemia was associated with adverse intra-ICU mortality in the overall cohort (23% vs. 13%; p < 0.001) and patients admitted for AMI (15% vs. 5%; p < 0.001) but not for septic patients (39% vs. 40%; p = 0.48). A medical history of type 2 diabetes (n = 337; 13%) was not associated with increased intra-ICU mortality (15% vs. 15%; p = 0.93) but in patients with severe hyperglycemia and/or a known medical history of type 2 diabetes considered in combination, an increased mortality in AMI patients (intra-ICU 5% vs. 13%; p < 0.001) but not in septic patients (intra-ICU 38% vs. 41%; p = 0.53) could be evidenced. The presence of hyperglycemia in critically ill patients has differential impact within the different etiological groups. Hyperglycemia in AMI patients might identify a sicker patient collective suffering from pre-diabetes or undiagnosed diabetes with its' known adverse consequences, especially in the long-term. Hyperglycemia in sepsis might be considered as adaptive survival mechanism to hypo-perfusion and consecutive lack of glucose in peripheral cells. AMI patients with hyperglycemic derailment during an ICU-stay should be closely followed-up and extensively screened for diabetes to improve patients' outcome.

Clinical and microbiological features of maternal sepsis: a retrospective study

BACKGROUND

Identifying pregnant women with sepsis is challenging because diagnostic clinical and laboratory criteria overlap with normal pregnant physiologic indices. Our primary study aim was to describe clinical and laboratory characteristics of women diagnosed with sepsis, severe sepsis and septic shock. Our secondary aim was to determine positive predictive values for International Classification of Disease (ICD)-9 billing codes for sepsis, severe sepsis, and septic shock.

METHODS

After gaining Institutional Review Board approval, we identified women with ICD-9 codes for sepsis, severe sepsis and septic shock who were admitted to a single tertiary obstetric center from 2007-2013. Diagnoses were confirmed using criteria from the International Sepsis Definitions Conference report. Demographic, obstetric, vital signs and laboratory data were abstracted by medical chart review.

RESULTS

We identified 190 women with sepsis-related ICD-9 codes: of these, 35 (18%) women met the criteria for a clinical diagnosis of sepsis, severe sepsis or septic shock. Twenty (57%) women had a sepsis-related diagnosis after cesarean delivery. Twenty-one (60%) women had one or more pre-existing medical conditions and 19 (54%) women had one or more obstetric-related conditions. The genital tract was the most common site of infection. We observed considerable heterogeneity in maternal vital signs and laboratory indices for women with ICD-9 codes for sepsis, severe sepsis, and septic shock. The positive predictive value for each sepsis-related ICD-9 code was low: 16% (95% CI 10 to 24%) for sepsis, 10% (95% CI 3 to 25%) for severe sepsis and 24% (95% CI 10 to 46%) for septic shock.

CONCLUSION

We identified marked heterogeneity in patient characteristics, clinical features, laboratory indices and microbiological findings among cohorts of women diagnosed with maternal sepsis, severe sepsis or septic shock. Based on our findings, the incidence of maternal sepsis using ICD-9 codes may be significantly overestimated.

Immunohistochemical Analysis of Leucocyte Subsets in the Sinonasal Mucosa of Cats with Upper Respiratory Tract Aspergillosis

Leucocyte populations in the sinonasal mucosa of cats with and without upper respiratory tract aspergillosis were compared using immunohistochemistry and computer-aided morphometry. Inflammation was identified in the nasal mucosa of all affected cats, comprising predominantly of lymphoplasmacytic infiltration of the lamina propria associated with epithelial proliferation and degeneration. There was intense and diffuse expression of class II antigens of the major histocompatibility complex, associated with sites of hyphal invasion with hyperplasia and ulceration of the epithelium adjacent to fungal elements. Significantly more CD79b(+) cells, total lymphocytes, immunoglobulin (Ig)-expressing cells and MAC387(+) cells infiltrated the epithelium and more IgG(+) cells and total Ig-expressing cells infiltrated the lamina propria in affected cats compared with controls. Importantly, the inflammatory profile in affected cats was not consistent with the T helper (Th)1 and Th17 cell-mediated response that confers protective acquired immunity against invasive aspergillosis in dogs and people and in murine models of the infection. This finding may help to explain the development of invasive aspergillosis in systemically immunocompetent cats.

Metformin and other glucose-lowering drug initiation and rates of community-based antibiotic use and hospital-treated infections in patients with type 2 diabetes: a Danish nationwide population-based cohort study

OBJECTIVE

Data on early risk of infection in patients receiving their first treatment for type 2 diabetes are limited. We examined rates of community-based antibiotic use and hospital-treated infection in initiators of metformin and other glucose-lowering drugs (GLDs).

DESIGN

Population-based cohort study using medical databases.

SETTING

General practice and hospitals in Denmark.

PARTICIPANTS

131 949 patients with type 2 diabetes who initiated pharmacotherapy with a GLD between 2005 and 2012.

EXPOSURE

Initial GLD used for pharmacotherapy.

MAIN OUTCOME MEASURES

We computed rates and adjusted HRs of community-based antibiotic use and hospital-treated infection associated with choice of initial GLD with reference to metformin initiation, using an intention-to-treat approach.

RESULTS

The rate of community-based antibiotic use was 362 per 1000 patient-years at risk (PYAR) and that for hospital-treated infection was 51 per 1000 PYAR. Compared with metformin, the risk of hospital-treated infection was slightly higher in sulfonylurea initiators (HR 1.12, 95% CI 1.08 to 1.16) and substantially higher in insulin initiators (HR 1.63, 95% CI 1.54 to 1.72) initiators after adjustment for comorbid conditions, comedications and other confounding factors. In contrast, virtually no difference was observed for overall community-based antibiotic use (HR 1.02, 95% CI 1.01 to 1.04, for sulfonylurea initiators; and 1.04, 95% CI 1.01 to 1.07, for insulin initiators).

CONCLUSIONS

Rates of community-based antibiotic treatment and hospitalisation for infection were high in patients receiving their first treatment for type 2 diabetes and differed with the choice of initial GLD used for pharmacotherapy.

Association of diabetes and diabetes treatment with the host response in critically ill sepsis patients

Background

Diabetes is associated with chronic inflammation and activation of the vascular endothelium and the coagulation system, which in a more acute manner are also observed in sepsis. Insulin and metformin exert immune modulatory effects. In this study, we aimed to determine the association of diabetes and preadmission insulin and metformin use with sepsis outcome and host response.

Methods

We evaluated 1104 patients with sepsis, admitted to the intensive care unit and stratified according to the presence or absence of diabetes mellitus. The host response was examined by a targeted approach (by measuring 15 plasma biomarkers reflective of pathways implicated in sepsis pathogenesis) and an unbiased approach (by analyzing whole genome expression profiles in blood leukocytes).

Results

Diabetes mellitus was not associated with differences in sepsis presentation or mortality up to 90 days after admission. Plasma biomarker measurements revealed signs of systemic inflammation, and strong endothelial and coagulation activation in patients with sepsis, none of which were altered in those with diabetes. Patients with and without diabetes mellitus, who had sepsis demonstrated similar transcriptional alterations, comprising 74 % of the expressed gene content and involving over-expression of genes associated with pro-inflammatory, anti-inflammatory, Toll-like receptor and metabolic signaling pathways and under-expression of genes associated with T cell signaling pathways. Amongst patients with diabetes mellitus and sepsis, preadmission treatment with insulin or metformin was not associated with an altered sepsis outcome or host response.

Conclusions

Neither diabetes mellitus nor preadmission insulin or metformin use are associated with altered disease presentation, outcome or host response in patients with sepsis requiring intensive care.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-016-1429-8) contains supplementary material, which is available to authorized users.