Bioecologic Control of Inflammation and Infection in Critical Illness

Chronic Critical Illness and PICS Nutritional Strategies

The nutritional hallmark of chronic critical illness (CCI) after sepsis is persistent inflammation, immunosuppression, and catabolism syndrome (PICS), which results in global resistance to the anabolic effect of nutritional supplements. This ultimately leaves these patients in a downward phenotypic spiral characterized by cachexia with profound weakness, decreased capacity for rehabilitation, and immunosuppression with the propensity for sepsis recidivism. The persistent catabolism is driven by a pathologic low-grade inflammation with the inability to return to homeostasis and by ongoing increased energy expenditure. Better critical care support systems and advances in technology have led to increased intensive care unit (ICU) survival, but CCI due to PICS with poor long-term outcomes has emerged as a frequent phenotype among ICU sepsis survivors. Unfortunately, therapies to mitigate or reverse PICS-CCI are limited, and recent evidence supports that these patients fail to respond to early ICU evidence-based nutrition protocols. A lack of randomized controlled trials has limited strong recommendations for nutrition adjuncts in these patients. However, based on experience in other conditions characterized by a similar phenotype, immunonutrients aimed at counteracting inflammation, immunosuppression, and catabolism may be important for improving outcomes in PICS-CCI patients. This manuscript intends to review several immunonutrients as adjunctive therapies in treating PICS-CCI.

Obesity, the deadly quartet and the contribution of the neglected daily organ rest - a new dimension of un-health and its prevention

The "deadly quartet": excessive weight, hypertension, impaired glucose homeostasis, and atherogenic dyslipidemia constitute a greater threat to health than the added effects of smoking and alcohol abuse. It is strongly associated with unrestricted consumption of processed, refined foods. Recent observations from experience in South East Asia shows that the interval between lifestyle changes and associated change in disease pattern is shorter than earlier believed. Recent experience from obesity studies in Africa demonstrates not only dramatic changes in health but also large social consequences from being overweight. Obesity is not only a result of overeating - dozens of other factors are known to contribute. Our palaeolithic forefathers and those living a similar lifestyle today are reported to rarely have diseases and to live a long life. One such group is the Hunzas, living in Northern Pakistan, are reported to live on a daily 1,800-calorie 99% plant-based diet, consisting in 73% of mostly unrefined/unprocessed carbohydrates, 17% fat and 10% protein. They, and most likely also our forefathers, do/did most likely only eat twice a day, at noon and early evening. Calorie-restriction (CR) and also fasting was early recommended and has been so during thousands of years - early Greek medicine and giants such as Hippocrates, Galenus and later also Paracelsus prescribed restrictions in eating and fasting. So did Middle Age physicians and other nutrition experts such as Louis Cornado. Today it is again practiced around the World. Overeating and heavy postprandial metabolism is a great burden to the body causing elevated levels in blood of endotoxin, increased inflammatory and oxidative stress, release of tumor necrosis factor-α, and other pro-inflammatory cytokines, increases in numbers of and activating of leukocytes, a reaction that is potentiated by the presence of large-chain fatty acids and sugars. Various metabolic, uremic, microbiota-derived and environmental poisons accumulate in large amounts in the adipose tissues. High levels of poisons in the adipose tissues decreases the turnover of fats in order to protect other organs. The content in adipose of POPs - altogether 17 dioxins/furans and 18 polychlorinated biphenyl congeners, has been reported to be 2-3 times higher in obese compared to lean persons. Daily fasting consisting in 16 to 18 hours of avoidance of calorie intake offers an interesting alternative. An attractive policy is to abstain from eating between 18:00 in the evening and 10:00 or 12:00 AM, a plan, which I personally have practiced during many years.

Probiotics for patients with hepatic encephalopathy

BACKGROUND

Hepatic encephalopathy is a disorder of brain function as a result of liver failure and/or portosystemic shunt. Both hepatic encephalopathy (clinically overt) and minimal hepatic encephalopathy (not clinically overt) significantly impair patient's quality of life and daily functioning and represent a significant burden on health care resources. Probiotics are live microorganisms, which when administered in adequate amounts may confer a health benefit on the host.

OBJECTIVES

To quantify the beneficial and harmful effects of any probiotic in any dosage, compared with placebo or no intervention, or with any other treatment for patients with any grade of acute or chronic hepatic encephalopathy as assessed from randomised trials.

SEARCH METHODS

We searched the The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, conference proceedings, reference lists of included trials and the WHO international clinical trials registry until April 2011 registry platform to identify new and ongoing trials.

SELECTION CRITERIA

We included randomised trials that compared probiotics in any dosage with placebo or no intervention, or with any other treatment in patients with hepatic encephalopathy.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed the risk of bias of the included trials and extracted data on relevant outcomes, with differences resolved by consensus. We conducted random-effects model meta-analysis due to obvious heterogeneity of patients and interventions. A P value of 0.05 or less was defined as significant. Dichotomous outcomes are expressed as risk ratio (RR) and continuous outcomes as mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included seven trials of which 550 participants were randomised. Four of the seven trials compared a probiotic with placebo or no treatment in 245 participants, another trial compared a probiotic with lactulose in 40 participants , and the remaining two trials compared a probiotic with both placebo and lactulose in 265 participants. Each trial used different types of probiotics. Duration of administration of the experimental intervention varied from 10 days to 180 days. Two trials were industry funded, and five were unclear about origin of funding. All trials had high risk of bias. When probiotics were compared with no treatment, there was no significant difference in all-cause mortality (2 trials, 105 participants; 1/57 (2%) versus 1/48 (2%): RR 0.72; 95% CI 0.08 to 6.60), lack of recovery (4 trials, 206 participants; 54/107 (50%) versus 68/99 (69%): RR 0.72; 95% CI 0.49 to 1.05), adverse events (3 trials, 145 participants; 2/77 (3%) versus 6/68 (9%): RR 0.34; 95% CI 0.08 to 1.42), quality of life (1 trial, 20 participants contributed to the physical quality of life measurement, 20 participants contributed to the mental quality of life: MD Physical 0.00; 95% CI -5.47 to 5.47; MD Mental 4.00; 95% CI -1.82 to 9.82), or change of/or withdrawal from treatment (3 trials, 175 participants; 11/92 (12%) versus 7/83 (8%): RR 1.28; 95% CI 0.52 to 3.19). No trial reported sepsis or duration of hospital stay as an outcome. Plasma ammonia concentration was significantly lower for participants treated with probiotic at one month (3 trials, 226 participants: MD -2.99 μmol/L; 95% CI -5.70 to -0.29) but not at two months (3 trials, 181 participants: MD -1.82 μmol/L; 95% CI -14.04 to 10.41). Plasma ammonia decreased the most in the participants treated with probiotic at three months (1 trial, 73 participants: MD -6.79 μmol/L; 95% CI -10.39 to -3.19). When probiotics were compared with lactulose no trial reported all-cause mortality, quality of life, duration of hospital stay, or septicaemia. There were no significant differences in lack of recovery (3 trials, 173 participants; 47/87 (54%) versus 44/86 (51%): RR 1.05; 95% CI 0.75 to 1.47), adverse events (2 trials, 111 participants; 3/56 (5%) versus 6/55 (11%): RR 0.57; 95% CI 0.06 to 5.74), change of/or withdrawal from treatment at one month (3 trials, 190 participants; 8/95 (8%) versus 7/95 (7%): RR 1.10; 95% CI 0.40 to 3.03), plasma ammonia concentration (2 trials, 93 participants: MD -6.61 μmol/L; 95% CI -30.05 to 16.84), or change in plasma ammonia concentration (1 trial, 77 participants: MD 1.16 μmol/L; 95% CI -1.96 to 4.28).

AUTHORS' CONCLUSIONS

The trials we located suffered from a high risk of systematic errors ('bias') and high risk of random errors ('play of chance'). While probiotics appear to reduce plasma ammonia concentration when compared with placebo or no intervention, we are unable to conclude that probiotics are efficacious in altering clinically relevant outcomes. Demonstration of unequivocal efficacy is needed before probiotics can be endorsed as effective therapy for hepatic encephalopathy. Further randomised clinical trials are needed.

Pro- and synbiotics to control inflammation and infection in patients with multiple injuries

BACKGROUND

A recent randomized clinical trial of our group disclosed considerable reduction of the infective sequelae after administration of a synbiotic formula, namely Synbiotic 2000FORTE, in patients with multiple injuries, the latter being a preparation of four probiotics. The mechanism of action of synbiotics was studied.

METHODS

A total of 72 patients with severe multiple injuries were allocated to a 15-day administration of either placebo or the synbiotic formula. The association of bloodstream infections, ventilator-associated pneumonia (VAP), serum levels of C-reactive protein (CRP), and endotoxins (LPS) were studied.

RESULTS

Sepsis in the field of bacteremia occurred in 13 patients treated with placebo (36.1%) compared with 5 patients treated with Synbiotic 2000FORTE (13.9%, p = 0.028 between groups). The time to progression to primary bacteremia was longer among patients treated with Synbiotic 2000FORTE compared with placebo (p = 0.0237 between groups). Twelve (33.3%) and five (13.9%) placebo-treated and probiotic-treated patients, respectively, developed ventilator-associated pneumonia with Acinetobacter baumannii as a bacterial cause (p = 0.047 between groups). Treatment with synbiotics was accompanied by reduction of white blood cell counts and LPS and CRP levels in either patients who did or did not develop sepsis.

CONCLUSIONS

Synbiotics contained in the studied formula decrease significantly the risk for sepsis by bloodstream infections and the occurrence of VAP by A. baumannii. The mechanisms of action might involve direct immunomodulatory effect, prevention of bacterial translocation, or most likely a combination of both.

Probiotics, critical illness, and methodologic bias

It has been proposed that probiotics can favorably influence the course of critically ill patients. To address this question, a limited systematic review was undertaken (MEDLINE search for articles published in English) to identify randomized, controlled trials that compared a group of critically ill patients taking probiotics with a group that did not. Ten such trials, mostly with high risks of methodologic bias, were identified. When the data were combined, the probiotics did not appear to influence mortality or duration of hospitalization. However, the recipients of the probiotics had fewer infectious episodes (absolute risk difference-21%). This effect was seen particularly in trials employing one combination of probiotic agents (Pediococcus pentosaceus, Leuconostoc mesenteroides, Lactobacillus paracasei, Lactobacillus plantarum). Unfortunately, this effect may be overly optimistic, as methodologic shortcomings could have introduced biases into the trials. Three trials of patients with severe acute pancreatitis were not included in this primary analysis because not all of the patients were in the intensive care unit. The largest of these, and the one with the lowest risk of bias, demonstrated that probiotics increased mortality, in part because of the precipitation of ischemic bowel disease (in patients who were also receiving postpyloric enteral nutrition infusions). Probiotics also appeared to reduce the incidence of antibiotic-associated diarrhea in hospitalized patients, although these trials did not specifically focus only on those who were critically ill. In summary, it is not clear that probiotics are beneficial (and they may even be harmful) in the critically ill patient group.

The role of prebiotics and synbiotics in critically ill patients

PURPOSE OF REVIEW

To examine current knowledge regarding the role of prebiotics in critical illness when administered singly or in combinations with probiotics (synbiotics).

RECENT FINDINGS

Recent experimental and clinical studies support the fact that bioecological intestinal control with early enteral nutrition enriched with synbiotics may reduce systemic inflammation, improve the immunological status of the intestinal mucosa and help prevent infections in critically ill patients. Three prebiotics, oligofructose, galactooligosaccharides and lactulose are able to modify the balance of intestinal microbiota. It appears that treatment with synbiotics during critical illness should restore the balance of microbial communities in a beneficial way with positive effects on intestinal permeability and bacterial translocation. Only data from small trials are currently available to support use of prebiotics and synbiotics in the treatment of different clinical scenarios. However, in some critical conditions, this supplementation has so far not been effective.

SUMMARY

Numerous questions about the molecular mechanisms of action or clinical indications of prebiotics remain unanswered. Large, randomized, multicentre trials are necessary to precisely define the role of prebiotics as therapeutic agents in critical illness. These trials must identify clinically significant improvements in relevant clinical endpoints before any large-scale usage is advocated for critical illness.

Cytokine dysregulation in chronic kidney disease: how can we treat it?

As the kidney is the major site for elimination of many cytokines, the delicate equilibrium of pro-inflammatory cytokines and their inhibitors is clearly dysregulated in chronic kidney disease (CKD) patients. The consequences of the altered immune response in uremia lead to a state of persistent inflammation which is highly prevalent among CKD patients and is linked to complications such as the development of protein-energy wasting and atherosclerotic vascular disease. The present review aims at reviewing this complex orchestration of uremic cytokines beyond the well-studied interleukin-6 and tumor necrosis factor-alpha. Finally, we update our current understanding on anti-inflammatory treatment strategies in CKD patients, including nutritional and lifestyle measurements, pharmacological intervention and specific anticytokine strategies targeting the dialytic procedure.

Advanced glycation and lipoxidation end products--amplifiers of inflammation: the role of food

BACKGROUND

High levels of glycated and lipoxidated proteins and peptides in the body are repeatedly associated with chronic diseases. These molecules are strongly associated with activation of a specific receptor called RAGE and a long-lasting exaggerated level of inflammation in the body.

METHODS

PubMed reports over 5000 papers plus >13,500 articles about the related HbA(1c), most of them published in the past 5 years. Most of the available abstracts have been read and approximately 800 full papers have been studied.

RESULTS

RAGE, a member of the immunoglobulin superfamily of cell surface molecules and receptor for advanced glycation end products, known since 1992, functions as a master switch, induces sustained activation of nuclear factor kappaB (NFkappaB), suppresses a series of endogenous autoregulatory functions, and converts long-lasting proinflammatory signals into sustained cellular dysfunction and disease. Its activation is associated with high levels of dysfunctioning proteins in body fluids and tissues, and is strongly associated with a series of diseases from allergy and Alzheimers to rheumatoid arthritis and urogenital disorders. Heat treatment, irradiation, and ionization of foods increase the content of dysfunctioning molecules.

CONCLUSIONS

More than half of the studies are performed in diabetes and chronic renal diseases; there are few studies in other diseases. Most of our knowledge is based on animal studies and in vitro studies. These effects are worth further exploration both experimentally and clinically. An avoidance of foods rich in deranged proteins and peptides, and the consumption of antioxidants, especially polyphenols, seem to counteract such a development.

Aggressive management of surgical emergencies

Increasing evidence suggests that two factors significantly influence outcome in a surgical emergency - premorbid health and the degree of inflammation during the first 24 h following trauma. Repeat observations suggest that the depth of post-trauma immunoparalysis reflects the height of early inflammatory response. Administration to surgical emergencies, as was routine in the past, of larger amounts of fluid and electrolytes, fat, sugar and nutrients seems counterproductive as it increases immune dysfunction, impairs resistance to disease and, in fact, increases morbidity. Instead, strong efforts should be made to limit the obvious superinflammation, which occurs during the first 24 h after trauma and, thereby, reduce the subsequent immunoparalysis. Several approaches show efficacy in limiting early superinflammation such as strict control of blood glucose, avoidance of stored blood when possible, supply of antioxidants, live lactic acid bacteria and plant fibres. This review focuses mainly on use of live lactic acid bacteria and plant fibres, often called synbiotics. Encouraging experience is reported from clinical trials in liver transplantation, severe pancreatitis and extensive trauma. Immediate control of inflammation by enteral nutrition and supply of antioxidants, lactic acid bacteria and fibres is facilitated by feeding tubes, introduced as early as possible on arrival at the hospital.