Supplemental immunoglobulin (ivIgG) treatment in 163 patients with sepsis and septic shock--an observational study as a prerequisite for placebo-controlled clinical trials

Sample Sizes Based on Exact Unconditional Tests for Phase II Clinical Trials with Historical Controls

Investigated in the setting of phase II clinical trials is the two-sample binomial problem of testing H0: pe = pc H1: pe > pc, where pe and pc are the unknown target population response rates for the experimental and control groups, respectively, using the usual Z-statistic with pooled variance estimator. The cornerstones that make this paper unique are as follows. First, the emphasis is on determining the sample size given that the control group information has already been collected (historical control). Second, exact unconditional inference, rather than an asymptotic method, is utilized. Sample size tables, contrasting the exact and asymptotic methods, are provided. Although asymptotic results were usually fairly close to the exact results, some important differences were observed.

Open randomized phase II trial of an extracorporeal endotoxin adsorber in suspected Gram-negative sepsis

OBJECTIVE

An initial phase II trial to investigate the safety and therapeutic effect of the endotoxin adsorber system EN 500 in septic patients suffering from presumed Gram-negative infection.

DESIGN

Open, controlled, prospective, randomized, multiple-center, parallel-group clinical trial.

SETTING

Intensive care units of 31 university-affiliated and community hospitals in Europe.

PATIENTS

One hundred forty-five patients with a clinical diagnosis of severe sepsis or septic shock due to suspected Gram-negative infection.

INTERVENTIONS

Patients were randomized to receive either standard therapy alone for sepsis (n = 76) or standard therapy plus extracorporeal endotoxin adsorption (n = 67) daily for the first 4 days following study entry.

MEASUREMENTS AND MAIN RESULTS

The primary end point was the proportion of responders (defined as a decrease in Acute Physiology and Chronic Health Evaluation II score by > or =4 points from study entry to day 4). Secondary outcomes were the Sequential Organ Failure Assessment score and its components, length of intensive care unit stay, survival rate, and safety of the adsorber treatment. Patient characteristics at entry were well balanced between the two treatment groups, except for a higher Sequential Organ Failure Assessment score in the adsorber group. On all-subjects-treated analysis, 65% of the adsorber group were responders vs. 57% for the standard (p =.389). A planned interim analysis restricted further enrollment to patients with peritonitis, in whom a slightly higher proportion of responders was observed with the adsorber treatment (69%) vs. standard treatment (54%, p =.159). There were no differences in survival, but adsorption treatment in peritonitis patients was associated with trends toward a reduction in length of intensive care unit stay and a more rapid decline in plasma endotoxin concentrations. There was a significantly greater reduction in platelet count with the adsorber; however, this did not require extra treatment.

CONCLUSIONS

The endotoxin adsorber system did not result in a significantly improved primary end point in patients with presumed Gram-negative sepsis. In patients with peritonitis, the adsorber treatment likewise did not result in significantly improved Acute Physiology and Chronic Health Evaluation II scores. There were no clinically important side effects. These results provide encouragement for further study of adsorber treatment in patients with high likelihood of Gram-negative sepsis (e.g., peritonitis).

Interactions among strategies associated with bacterial infection: pathogenicity, epidemicity, and antibiotic resistance

Infections have been the major cause of disease throughout the history of human populations. With the introduction of antibiotics, it was thought that this problem should disappear. However, bacteria have been able to evolve to become antibiotic resistant. Nowadays, a proficient pathogen must be virulent, epidemic, and resistant to antibiotics. Analysis of the interplay among these features of bacterial populations is needed to predict the future of infectious diseases. In this regard, we have reviewed the genetic linkage of antibiotic resistance and bacterial virulence in the same genetic determinants as well as the cross talk between antibiotic resistance and virulence regulatory circuits with the aim of understanding the effect of acquisition of resistance on bacterial virulence. We also discuss the possibility that antibiotic resistance and bacterial virulence might prevail as linked phenotypes in the future. The novel situation brought about by the worldwide use of antibiotics is undoubtedly changing bacterial populations. These changes might alter the properties of not only bacterial pathogens, but also the normal host microbiota. The evolutionary consequences of the release of antibiotics into the environment are largely unknown, but most probably restoration of the microbiota from the preantibiotic era is beyond our current abilities.

Sepsis and septic shock. II. Treatment

Mortality from septic shock is considerable despite the advantages of cardiovascular support and antibiotic therapy. This article reviews current therapy of septic shock including immunotherapy and further possibilities of septic shock treatment. The role of cytokines, their inhibitors and antibodies to endotoxin is mentioned. Although these treatments hold much promise for the future, careful evaluation of both the benefits and complications of therapy is needed before widespread clinical use can be recommended.