Osamu Tasaki

Changes in CSF S100B and cytokine concentrations in early-phase severe traumatic brain injury.

S100B protein (S100B) has been described as a marker of brain injury. Various cytokines also increase in the cerebrospinal fluid (CSF) of patients with severe traumatic brain injury (TBI). Thus, we investigated early changes in the concentrations of CSF S100B and various cytokines after TBI and evaluated the relations of both S100B and cytokines to intracranial pressure (ICP) and prognosis. Twenty-three patients with severe TBI and a Glasgow Coma Scale score of 8 or less on admission were included in this study. CSF and serum samples were obtained on admission and at 6, 12, 24, 48, 72, and 96 h after injury. CSF concentrations of S100B and CSF and serum concentrations of five cytokines (IL-1β, TNF-α, IL-6, IL-8, and IL-10) were measured and compared. The CSF S100B concentration was increased for 6 h after injury and decreased thereafter. The CSF concentrations of IL-6 and IL-8 peaked within 6 h after injury; other cytokines (IL-1β, TNF-α, and IL-10) were elevated for 24 h after injury and gradually decreased thereafter. Peak CSF S100B concentrations correlated significantly with ICP determined at the time CSF samples were taken (r2 = 0.729, P < 0.0001). For the cytokines investigated, only the peak CSF IL-1β concentration correlated significantly and positively with the peak CSF S100B concentration (r2 = 0.397, P < 0.005). Peak CSF concentrations of S100B (1649 ± 415 μg/L, mean ± SEM) and IL-1β (16.5 ± 3.3 pg/mL) in the 6 patients with high ICP were significantly higher than those (233 ± 67 μg/L, 7.6 ± 1.7 pg/mL, respectively) in the 17 patients with low ICP (P < 0.05). The CSF S100B concentration (1231 ± 378 μg/L) in eight patients with an unfavorable outcome was significantly higher than that (267 ± 108 μg/L) in 15 patients with a favorable outcome (P < 0.05). The CSF IL-1β concentration (14.8 ± 3.4 pg/mL) in eight patients with an unfavorable outcome tended to be higher than that (7.3 ± 1.5 pg/mL) in 15 patients with a favorable outcome (P = 0.057). CSF concentrations of S100B and cytokines peak within 24 h after severe TBI and decrease gradually thereafter. CSF S100B and IL-1β may be useful as predictors of outcome in cases of severe TBI.

Cerebrospinal fluid concentrations of anti-inflammatory mediators in early-phase severe traumatic brain injury.

In our previous study of patients with early-phase severe traumatic brain injury (TBI), the anti-inflammatory interleukin (IL)-10 concentration was lower in cerebrospinal fluid (CSF) than in serum, whereas proinflammatory IL-1β and tumor necrosis factor (TNF)-α concentrations were higher in CSF than in serum. To clarify the influence of additional injury on this disproportion between proinflammatory and anti-inflammatory mediators, we compared their CSF and serum concentrations in patients with severe TBI with and without additional injury. All 35 study patients (18 with and 17 without additional injury) had a Glasgow Coma Scale score of 8 or less upon admission. With the exception of additional injury, clinical characteristics did not differ significantly between groups. CSF and serum concentrations of two proinflammatory mediators (IL-1β and TNF-α,) and three anti-inflammatory mediators (IL-1 receptor antagonist [IL-1ra], soluble TNF receptor-I [sTNFr-I], and IL-10) were measured and compared at 6 h after injury. CSF concentrations of proinflammatory mediators were much higher than the corresponding serum concentrations in both patient groups (P < 0.001). In contrast, serum concentrations of anti-inflammatory mediators were much higher than the paired CSF concentrations in patients with additional injury (P < 0.001), but serum concentrations were lower than or equal to the corresponding CSF concentrations in patients without additional injury. CSF concentrations of IL-1β, IL-1ra, sTNFr-I, and IL-10 were significantly higher (P < 0.01 for all) in patients with high intracranial pressure (ICP; n = 11) than in patients with low ICP (n = 24), and were also significantly higher (P < 0.05 for all) in patients with an unfavorable outcome (n = 14) than in patients with a favorable outcome (n = 21). These findings indicate that increased serum concentrations of anti-inflammatory mediators after severe TBI are mainly due to additional extracranial injury. We conclude that anti-inflammatory mediators in CSF may be useful indicators of the severity of brain damage in terms of ICP as well as overall prognosis of patients with severe TBI.

Evaluation of pathogen detection from clinical samples by real-time polymerase chain reaction using a sepsis pathogen DNA detection kit

IntroductionSepsis is a serious medical condition that requires rapidly administered, appropriate antibiotic treatment. Conventional methods take three or more days for final pathogen identification and antimicrobial susceptibility testing. We organized a prospective observational multicenter study in three study sites to evaluate the diagnostic accuracy and potential clinical utility of the SeptiFast system, a multiplex pathogen detection system used in the clinical setting to support early diagnosis of bloodstream infections.MethodsA total of 212 patients, suspected of having systemic inflammatory response syndrome (SIRS) caused by bacterial or fungal infection, were enrolled in the study. From these patients, 407 blood samples were taken and blood culture analysis was performed to identify pathogens. Whole blood was also collected for DNA Detection Kit analysis immediately after its collection for blood culture. The results of the DNA Detection Kit, blood culture and other culture tests were compared. The chosen antimicrobial treatment in patients whose samples tested positive in the DNA Detection Kit and/or blood culture analysis was examined to evaluate the effect of concomitant antibiotic exposure on the results of these analyses.ResultsSeptiFast analysis gave a positive result for 55 samples, while 43 samples were positive in blood culture analysis. The DNA Detection Kit identified a pathogen in 11.3% (45/400) of the samples, compared to 8.0% (32/400) by blood culture analysis. Twenty-three pathogens were detected by SeptiFast only; conversely, this system missed five episodes of clinically significant bacteremia (Methicillin-resistant Staphylococcus aureus (MRSA), 2; Pseudomonas aeruginosa, 1; Klebsiella spp, 1; Enterococcus faecium, 1). The number of samples that tested positive was significantly increased by combining the result of the blood culture analysis with those of the DNA Detection Kit analysis (P = 0.01). Among antibiotic pre-treated patients (prevalence, 72%), SeptiFast analysis detected more bacteria/fungi, and was less influenced by antibiotic exposure, compared with blood culture analysis (P = 0.02).ConclusionsThis rapid multiplex pathogen detection system complemented traditional culture-based methods and offered some added diagnostic value for the timely detection of causative pathogens, particularly in antibiotic pre-treated patients. Adequately designed intervention studies are needed to prove its clinical effectiveness in improving appropriate antibiotic selection and patient outcomes.

Presence of Neutrophil Extracellular Traps and Citrullinated Histone H3 in the Bloodstream of Critically Ill Patients

Neutrophil extracellular traps (NETs), a newly identified immune mechanism, are induced by inflammatory stimuli. Modification by citrullination of histone H3 is thought to be involved in the in vitro formation of NETs. The purposes of this study were to evaluate whether NETs and citrullinated histone H3 (Cit-H3) are present in the bloodstream of critically ill patients and to identify correlations with clinical and biological parameters. Blood samples were collected from intubated patients at the time of ICU admission from April to June 2011. To identify NETs, DNA and histone H3 were visualized simultaneously by immunofluorescence in blood smears. Cit-H3 was detected using a specific antibody. We assessed relationships of the presence of NETs and Cit-H3 with the existence of bacteria in tracheal aspirate, SIRS, diagnosis, WBC count, and concentrations of IL-8, TNF-α, cf-DNA, lactate, and HMGB1. Forty-nine patients were included. The median of age was 66.0 (IQR: 52.5–76.0) years. The diagnoses included trauma (7, 14.3%), infection (14, 28.6%), resuscitation from cardiopulmonary arrest (8, 16.3%), acute poisoning (4, 8.1%), heart disease (4, 8.1%), brain stroke (8, 16.3%), heat stroke (2, 4.1%), and others (2, 4.1%). We identified NETs in 5 patients and Cit-H3 in 11 patients. NETs and/or Cit-H3 were observed more frequently in “the presence of bacteria in tracheal aspirate” group (11/22, 50.0%) than in “the absence of bacteria in tracheal aspirate” group (4/27, 14.8%) (p<.01). Multiple logistic regression analysis showed that only the presence of bacteria in tracheal aspirate was significantly associated with the presence of NETs and/or Cit-H3. The presence of bacteria in tracheal aspirate may be one important factor associated with NET formation. NETs may play a pivotal role in the biological defense against the dissemination of pathogens from the respiratory tract to the bloodstream in potentially infected patients.

Prognostic indicators and outcome prediction model for severe traumatic brain injury

BACKGROUND Although some predictive models for patient outcomes after severe traumatic brain injury have been proposed, a mathematical model with high predictive value has not been established. The purpose of the present study was to analyze the most important indicators of prognosis and to develop the best outcome prediction model. METHODS One hundred eleven consecutive patients with a Glasgow Coma Scale score of <9 were examined and 14 factors were evaluated. Intracranial pressure and cerebral perfusion pressure were recorded at admission to the intensive care unit. The absence of the basal cisterns, presence of extensive subarachnoid hemorrhage, and degree of midline shift were evaluated by means of computed tomography within 24 hours after injury. Multivariate logistic regression analysis was used to identify independent risk factors for a poor prognosis and to develop the best prediction model. RESULTS The best model included the following variables: age (p < 0.01), light reflex (p = 0.01), extensive subarachnoid hemorrhage (p = 0.01), intracranial pressure (p = 0.04), and midline shift (p = 0.12). Positive predictive value of the model was 97.3%, negative predictive value was 87.1%, and overall predictive value was 94.2%. The area under the receiver operating characteristic curve was 0.977, and the p value for the Hosmer-Lemeshow goodness-of-fit was 0.866. CONCLUSIONS Our predictive model based on age, absence of light reflex, presence of extensive subarachnoid hemorrhage, intracranial pressure, and midline shift was shown to have high predictive value and will be useful for decision making, review of treatment, and family counseling in case of traumatic brain injury.

Prognostic impact of fecal pH in critically ill patients

IntroductionWe have reported that altered gut flora is associated with septic complications and eventual death in critically ill patients with systemic inflammatory response syndrome. It is unclear how fecal pH affects these patients. We sought to determine whether fecal pH can be used as an assessment tool for the clinical course of critically ill patients.MethodsFour hundred ninety-one fecal samples were collected from 138 patients who were admitted to the Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Japan. These patients were treated in the intensive care unit for more than 2 days. Fecal pH, fecal organic acids, and fecal bacteria counts were measured and compared by survived group and nonsurvived group, or nonbacteremia group and bacteremia group. Logistic regression was used to estimate relations between fecal pH, age, sex, or APACHE II score and mortality, and incidence of bacteremia. Differences in fecal organic acids or fecal bacteria counts among acidic, neutral, and alkaline feces were analyzed.ResultsThe increase of fecal pH 6.6 was significantly associated with the increased mortality (odds ratio, 2.46; 95% confidence interval, 1.25 to 4.82) or incidence of bacteremia (3.25; 1.67 to 6.30). Total organic acid was increased in acidic feces and decreased in alkaline feces. Lactic acid, succinic acid, and formic acid were the main contributors to acidity in acidic feces. In alkaline feces, acetic acid was significantly decreased. Propionic acid was markedly decreased in both acidic and alkaline feces compared with neutral feces. No differences were noted among the groups in bacterial counts.ConclusionsThe data presented here demonstrate that the fecal pH range that extended beyond the normal range was associated with the clinical course and prognosis of critically ill patients.

The dimer and trimer of 3-hydroxybutyrate oligomer as a precursor of ketone bodies for nutritional care.

BACKGROUND Ketone bodies have been considered as a means of providing energy because of their good penetration and rapid diffusion in peripheral tissues. However, because the currently available form of 3-hydroxybu-tyrate is the sodium salt, the sodium load is problematic. To avoid it, a mixture of dimer and trimer has been prepared as a precursor of D-3-hydroxybutyrate. The purpose of this study was to investigate whether and how the solution would be converted to monomers. METHODS The plasma concentration of 3-hydroxybutyrate monomer was measured in 10 rats during infusion of dimer and trimer. Stepwise dilutions of the solution were incubated with serum and liver homogenates from five rats, serum samples from five volunteers, and a liver sample from one patient with liver injury. The solution also was incubated with carboxylesterase and triacylglycerol lipase. The concentration of monomer in the medium was measured after incubation. RESULTS The plasma concentration of 3-hydroxybutyrate monomer reached 572 +/- 11 micromol/L 15 minutes after beginning infusion of the mixture at a rate of 25 micromol x kg(-1) x min(-1) and 270 +/- 40 micromol/L at a rate of 12.5 micromol x kg(-1) min(-1). The solution was converted completely to monomers when incubated with rat serum or liver homogenate for 10 minutes. The mixture also was hydrolyzed by human liver homogenate but not by serum. CONCLUSIONS The dimer and trimer of 3-hydroxybutyrate can be converted rapidly to monomer in rat and human tissues. 3-Hydroxybutyrate oligomers could be an energy substrate for injured patients.

Altered balance of the aminogram in patients with sepsis – The relation to mortality

BACKGROUND & AIMS Protein metabolism is important in healing wounds, supporting immune function, and maintaining lean body mass. Determination of adequate requirements of amino acids has not been thoroughly clarified in critically ill patients. The purpose of this study was to evaluate 23 plasma amino acids in patients with sepsis and determine prognostic factors. METHODS This study was a retrospective study. Plasma aminograms were measured in patients with sepsis. We evaluated minimum and maximum values of each amino acid and evaluated prognostic factors by multivariate logistic regression analysis and classification and regression tree (CART) analysis. RESULTS The study comprised 77 patients. The median intensive care unit (ICU) stay was 30 days (interquartile range 19.5-55.5 days). Whole mortality rate was 39.0%. Maximum values of glutamine, glutamate, glycine, alanine, methionine, phenylalanine, and histidine and minimum values of glutamate, taurine, serine, isoleucine, leucine, tyrosine, ornithine, tryptophan, and arginine were significantly different between survivors and non-survivors (P < 0.05). Statistical analysis using CART analysis revealed the minimum value of glutamate and maximum value of methionine to be significant prognostic factors for mortality (P < 0.05). CONCLUSION Plasma aminograms were significantly altered in patients with sepsis. Altered balance of aminograms was significantly associated with mortality in patients with sepsis requiring a long ICU stay.

Acute Cerebral Blood Flow Variations after Human Cardiac Arrest Assessed by Stable Xenon Enhanced Computed Tomography

In this study, changes in cerebral blood flow (CBF) during acute phase after cardiopulmonary arrest (CPA) were examined in patients using stable Xenon enhanced computed tomography (Xe-CT). All patients (8) were stabilized hemodynamically within 4 hours after admission, and Xe-CT was performed immediately after restoration of spontaneous circulation (ROSC) at 8, 24, 48, 96 and 168 hours after ROSC. The progress of patients was monitored in other hospitals and clinics after discharge. Neurological outcomes were evaluated using the Glasgow outcome scale (GOS) 6 months after admission, and scores were compared against changes in CBF. Patients were grouped by prognosis. Four patients belonged to Group A (good recovery) and Group B (2 severely disabled, 2 in persistent vegetative state). The pattern of change in CBF after ROSC was found to be significantly different between Groups A and B (p <0.05). The CBF ratio relative to normal controls was higher in Group B than Group A within 48 hours after ROSC. However, at 48, 96, and 168 hours after ROSC, the opposite was observed: The CBF ratio was significantly higher in Group A than Group B (p<0.05). Based on these results, we concluded that CBF in the patients who survived after CPA changed remarkable especially within the first week. Furthermore, patients with abnormally low CBF that returns to supernormal within the first 48 hours following CPA can be expected to recover well neurologically.

Gut microbiota and environment in patients with major burns – a preliminary report.

INTRODUCTION The gut is an important target organ after severe insult. Gut microbiota have an important role in immune response. However, the gut microbiota and environment have not been clarified in patients with burns. Therefore, we serially evaluated the gut microbiota and environment in patients with major burns. METHODS Fecal samples from five patients with major burns were measured for quantitative evaluation of the gut microbiota. RESULTS In the four survivors of major burns, the numbers of beneficial bacteria, especially those of total obligate anaerobes and Bifidobacterium, initially decreased, but then increased as the condition of the survivors improved. By contrast, the numbers severely decreased in the non-survivor as gut failure and sepsis progressed. The number of pathogenic bacteria such as Pseudomonas and Candida did not continue to increase in the survivors, whereas in the non-survivor the number increased and continued to higher counts. Short-chain fatty acids such as propionic and butyric acids decreased to lower-than-normal levels but tended to increase after recovery in the survivors. The levels remained below normal in the non-survivor. CONCLUSIONS The gut microbiota and environment are severely altered in patients with major burns. Consequently, abnormal gut conditions may have an influence on the systemic inflammatory response and multiple organ dysfunction syndrome. A novel treatment to maintain the gut microbiota and environment is expected in the future.