The Association Between Intra-abdominal View and Systemic Cytokine Response in Complicated Intra-abdominal Infections

BACKGROUND

There is a wide variety of disease severity in patients with complicated intraabdominal infection (cIAI). The prognostic role of intraabdominal view (IAV) was recently studied, and an IAV score was introduced. The aim of this study was to analyze the associations between the preoperative levels of eight relevant circulating cytokines and IAV components, the IAV score, as well as outcome.

MATERIALS AND METHODS

This was a single-center prospective study. The study cohort consisted of operatively managed adult patients with a cIAI. Preoperative plasma levels of eight cytokines were determined. The operating surgeon filled a form describing IAV. Outcomes analyzed were 30-day mortality and the development of organ dysfunctions requiring intensive care unit admission.

RESULTS

A total of 131 patients with cIAI were analyzed, 30-day mortality was 9.9% (n = 13), and 28 (21.4%) patients had postoperative organ dysfunctions. All components of IAV, the IAV score, and outcomes were associated with various cytokine levels. Interleukin-8 was the most competent marker associating with all the variables assessed in this study: diffuse peritonitis (P < 0.001), substantial diffuse redness (P = 0.012), substantial diffuse fibrin (P = 0.003), fecal or bile as exudate (P = 0.001), nonappendiceal source of infection (P < 0.001), IAV Score groups (P < 0.001), organ dysfunctions (P < 0.001), and 30-day mortality (P = 0.035).

CONCLUSIONS

Various cytokines associate with the IAV and outcome. IL-8 showed the best overall performance. The results emphasize the role of the surgeons' perception of the IAV. IAV provides an approximation of the magnitude of the systemic inflammatory response.

Diversity of Saccharomyces boulardii CNCM I-745 mechanisms of action against intestinal infections

The yeast Saccharomyces boulardii CNCM I-745 is one of the probiotics recommended for the prevention of antibiotic-associated diarrhea. Studies conducted in vivo and in vitro demonstrated that in the case of infectious diseases there are two potential sites of action of Saccharomyces boulardii CNCM I-745: (1) An action on enteropathogenic microorganisms (adhesion of bacteria and their elimination or an effect on their virulence factors: Toxins, lipopolysaccharide, etc.); and (2) a direct action on the intestinal mucosa (trophic effects, effects on epithelial reconstitution, anti-secretory effects, anti-inflammatory, immunomodulators). Oral administration of Saccharomyces boulardii CNCM I-745 to healthy subjects does not alter their microbiota. However, in the case of diseases associated with the use of antibiotics or chronic diarrhea, Saccharomyces boulardii CNCM I-745 can restore the intestinal microbiota faster. The interaction of Saccharomyces boulardii CNCM I-745 with the innate immune system have been recently demonstrated thus opening up a new therapeutic potential of this yeast in the case of diseases associated with intestinal infections but also other pathologies associated with dysbiosis such as inflammatory diseases.

[Immunological characteristics of peritoneal cavity and intra-abdominal infection]

Despite the evolution of aggressive surgical techniques, extensive methods of supportive care and a vast array of anti-microbial options, intra-abdominal infection (IAI) is still a challenging clinical issue. Especially, when progressed IAI with septic complications because of unbalanced immune responses, the prognosis will deteriorated significantly. Recent studies indicate that besides the natural immunological cells, including macrophages and neutrophils, local immunological characteristics of peritoneal cavity should be studied with great attention. Among them, the omentum is considered to be a visceral adipose tissue with unique immune function. The milky spots(MSs) formed by the accumulation of immune cells performs immune surveillance and has a lymph node-like immune function, which is very important for the immune defense of the abdominal cavity. B1 cells and two types of intrinsic lymphocytes(ILC2) in the peritoneal cavity, although belonging to the lymphatic lineage, may play an important role in abdominal infections, especially in the early stages of the disease, due to their rapid responsiveness and acquired immune function. Therefore, paying attention to the immunological characteristics of the peritoneal cavity, and elucidating the changes, functions and regulatory mechanisms of B1 cells and ILC2 around the MSs and their components in the process of IAI, in order to explore the immunomodulation targets of blocking the infection from local to systemic dissemination, may be the key to solving the clinical problem of severe IAI and improving prognosis.

[PREDICTORS OF UNFAVORABLE OUTCOME IN PATIENTS WITH ABDOMINAL SEPSIS.]

OBJECTIVE

The study focuses on identifying predictors of treatment outcome in abdominal sepsis (AS) in humans.

SUBJECTS AND METHODS

70 patients underwent determination of blood pressure, heart rate, SpO , the content of leu- kocytes, albumin, C-reactive protein, fibrinogen and TNF-a in arterial (femoral artery) and venous (subclavian vein) blood. Automatic biochemical analyzer Cobas-Integra 400 ('Roche", Switzerland), the test system Microlab STAR ELISA kit reagents "alpha TNF - ELISA - best" were used during the research. System statistical analysis included paired comparison of patients with favorable (n=27) and lethal (n=43) outcome, correlation, cluster; discriminating analysis, multidimensional scaling and plotting ROC curves with sensitivity and specificity indicators predictive value.

RESULTS

Identfied predictors of outcome inpatients,from which to form a predictive model of CRP fibrinogen, albumin, and TNF-a arterial blood. It is established that if the basic treatment of the patient CRP <9,8 g/l,fibrinogen >3,43 g/l, albumin <28,9 gl and TNF-a <499,3 ng/ml, the probability of death was statistically significantly higher thanfavorable.

CONCLUSION

It is assumed that therapeutic measures should be aimed at correction of the above mentioned indicators.

The antimicrobial peptide, epinecidin-1, mediates secretion of cytokines in the immune response to bacterial infection in mice

Epinecidin-1, an antimicrobial peptide which encodes 21 amino acids, was isolated from a marine grouper (Epinephelus coioides). In this study, we investigated its immunomodulatory functions in mice co-injected with Pseudomonas aeruginosa. In vivo results showed that the synthetic epinecidin-1 peptide induced significant secretion of immunoglobulin G1 (IgG1) in mice co-injected with P. aeruginosa. Moreover, after injection of 40, 100, 200, or 500 μg epinecidin-1/mouse, we detected IgM, IgG, IgG1, and IgG2a in mice treated for 1, 2, 3, 7, 14, 21, and 28 days. Results showed that there were no significant differences in IgM, IgG, or IgG2a between mice injected with epinecidin-1 alone. IgG1 increased to a peak at 24 h, 7 days, and 28 days after an epinecidin-1 (40 μg/mouse) injection. Injection of 500 μg epinecidin-1/mouse increased IgG1 to peaks at 2 and 3 days; injection of 100 μg epinecidin-1/mouse increased IgG1 to a peak at 21 days. This supports epinecidin-1 being able to activate the Th2 cell response (enhance IgG1 production) against P. aeruginosa infection. Treatment with different concentrations of epinecidin-1 in mice elevated plasma interleukin (IL)-10 to initial peaks at 24 and 48 h, and it showed a second peak at 16 days. In RAW264.7 cells, treatment with epinecidin-1 alone did not produce significant changes in tumor necrosis factor (TNF)-α protein secretion at 1, 6, or 24h after treatment with 3.75, 7.5, or 15 μg/ml epinecidin-1 compared to the lipopolysaccharide group.

[Relation of mesenteric lymph node and innate immune function in septic rats]

OBJECTIVE

To investigate the changes in T helper cells (Th1 and Th2) of mesenteric lymph node (MLN) and blood Th1 and Th2 cells in septic rats.

METHODS

Ninety-six male Wistar rats were randomly divided into two groups according to random number table method: sham operation group and model group. Intra-abdominal infection with sepsis was induced by cecal ligation and puncture (CLP). Eight rats in each group were sacrificed after collection of blood samples and MLN samples at 0, 6, 12, 24, 48 and 72 hours after CLP. The ratio of Th1/Th2 and the percentage of regulatory T cell (Treg) in CD4+ T cells in blood and MLN were respectively determined by flow cytometry.

RESULTS

In model group, the ratio of Th1/Th2 in abdominal aorta blood increased significantly at 6 hours and reached summit at 12 hours, then it decreased persistently, and when compared with sham group, the ratio of Th1/Th2 was significantly higher at 6, 12, 24 hours (0.82±0.15 vs. 0.60±0.22, 1.23±0.44 vs. 0.76±0.31, 0.85±0.25 vs. 0.66±0.32) and lower at 72 hours (0.41±0.16 vs. 0.59±0.13, P<0.05 or P<0.01). The ratio of Th1/Th2 in MLN of model group reached summit at 6 hours, then decreased significantly, and when compared with sham group, the ratio of Th1/Th2 was significantly higher at 6 hours (1.01±0.16 vs. 0.52±0.13) and lower at 12, 24, 48 and 72 hours (0.34±0.11 vs. 0.53±0.09, 0.23±0.08 vs. 0.51±0.09, 0.17±0.07 vs. 0.47±0.15, 0.16±0.06 vs. 0.53±0.11, P<0.05 or P<0.01). Compared with sham group, the percentage of Treg in MLN of model group was increased at 12, 24, 48 and 72 hours after CLP (9.62±0.69 vs. 7.65±0.67, 9.84±0.74 vs. 8.08±1.06, 10.95±2.09 vs. 7.83±1.15, 10.81±1.34 vs. 8.35±1.12, P<0.05 or P<0.01). There was a negative correlation between the ratio of Th1/Th2 and the percentage of Treg in MLN (r=-0.882, P<0.05).

CONCLUSION

Cellular immune function of MLN is suppressed during severe intra-abdominal infection, which induces translocation of gut-derived endotoxin to mesenteric lymphatics, resulting in corporal immuno-suppression, with manifestation of Th1/Th2 cell shift. Immuno-suppression of MLN is related to a higher percentage of Treg due to the effect of endotoxin.