S100B protein in carbon monoxide poisoning: a pilot study

A pilot study of neuroprotective effect of granulocyte colony-stimulating factor (G-CSF) in patients with carbon monoxide poisoning: a double-blind, randomized, placebo-controlled trial

Although neuroprotective effects of granulocyte colony-stimulating factor (G-CSF) have been shown in rats exposed to carbon monoxide (CO), this pilot clinical trial was performed to assess the feasibility of treatment with G-CSF in patients with acute CO poisoning. A double-blind, randomized, placebo-controlled pilot clinical trial was conducted on twenty-six patients with acute CO poisoning. G-CSF (90 μg/kg) was administered intravenously for 72 h. Demographic data, routine laboratory tests, differential blood counts, venous blood gas, and adverse reactions were recorded. The primary endpoint was brain ischemia improvement based on CT findings and the secondary endpoints examined improvements in the modified Rankin Scale (mRS), National Institutes of Health Stroke Scale (NIHSS), and Barthel Index as well as S-100β concentrations. Fourteen patients received G-CSF, and 12 received a placebo. Twenty-six were followed for 30 days and no one in both groups died during follow-up. Neurological complications, brain ischemic changes, Barthel, and mRS were compared between the two groups on determined days after the onset of therapeutic intervention, and no significant differences were observed between the two groups. Favorable results were achieved for treated patients by different measures; NIHSS was decreased 72 h after treatment (p = 0.046), and S-100β levels were significantly higher in the G-CSF group than in the control group, 12 h and 72 h after the treatment. G-CSF appears to have potential effects on several clinical parameters in patients with acute CO poisoning. The trial was registered at the Iranian Registry of Clinical Trials with the ID: (IRCT201607232083N7).

Potential Role of Serum S-100β Protein as a Predictor of Cardiotoxicity and Clinical Poor Outcome in Acute Amphetamine Intoxication

Cardio- and neurotoxicity of amphetamines play an important role in worsening morbidity, making the initial evaluation of the patient's status a potentially lifesaving action. The current study hypothesized that the S-100β serum level could predict the severity of acute amphetamine toxicity and the in-hospital outcome. The current study is a prospective cohort study conducted on 77 patients diagnosed with acute amphetamine exposure and referred to Aseer Poison Control Center, Saudi Arabia. The patients admitted to ICU showed significantly higher serum levels of S-100β in comparison to those not admitted (p < 0.05). Moreover, the S-100β level was significantly elevated among patients with prolonged QTc intervals. Receiver-operating characteristic curve of S-100β serum level as an in-hospital outcome predictor showed that at a cutoff value > 0.430 ug/L, the sensitivity of S-100β serum level as severity predictor was 100%, and the specificity was 74.1%. In conclusion, the current study revealed that the S-100β serum level could be used as an outcome predictor in hospital admission cases due to toxic amphetamine exposure and offers an idea about the cardiac and neuronal involvement. This can help select patients who will benefit most from ICU admission and early management and assess the severity of cases in settings where GC-MS is not available.

S-100β in predicting the need of hyperbaric oxygen in CO-induced delayed neurological sequels

BACKGROUND

Delayed neurological sequels (DNS) have been described after carbon monoxide (CO) poisoning. There is a need to find a new prognostic marker to guide the use of hyperbaric oxygen (HBO) therapy.

AIM

To evaluate serum S-100β level in patients presenting with acute CO poisoning as an indicator of poisoning severity and predictor of DNS occurrence and HBO need in those patients.

METHODS

This prospective cohort study included patients with acute CO poisoning. On admission, carboxyhemoglobin (COHb) and S-100β levels were measured. Patients were followed up for 6 months for signs of DNS.

RESULTS

Out of 50 patients, 6 only developed DNS. The mean of S-100β levels was significantly higher in patients with severe poisoning and those with DNS. Receiver operating characteristic curve analysis revealed that S-100β had an area under the curve 0. 871; at a cutoff value ≥ 0.67 µg/L, its sensitivity and specificity were 100% and 77.3%, respectively. The sensitivity of S-100β was significantly higher than that of COHb, while its specificity and overall accuracy were significantly higher than those of HBO criteria.

CONCLUSION

Serum S-100β level on admission could be a marker of poisoning severity and a predictor of CO-induced DNS development that guides the use of HBO therapy.

Serum markers and development of delayed neuropsychological sequelae after acute carbon monoxide poisoning: anion gap, lactate, osmolarity, S100B protein, and interleukin-6

Objective

Reliable biomarkers of delayed neuropsychological sequelae (DNS) after acute carbon monoxide (CO) poisoning are lacking. This study investigated the associations between potential serum markers and the development of DNS after acute CO poisoning.

Methods

Retrospective chart reviews were conducted for patients diagnosed with acute CO poisoning during a 28-month period. The patients were divided into two groups according to the presence or absence of having developed DNS. Multivariate analysis was performed to identify predictors of DNS after CO poisoning.

Results

Of a total of 102 patients, 10 (9.8%) developed DNS. The levels of serum osmolarity, S100B protein, and serum lactate, as well as serum anion gap, were statistically significant in univariate analysis. Multiple logistic regression analysis showed that anion gap (adjusted odds ratio [AOR], 1.36; 95% confidence interval [CI], 1.11 to 1.88), serum lactate level (AOR, 1.74; 95% CI, 1.26 to 2.75), and serum S100B protein level ([AOR, 7.02×10⁵; 95% CI, 4.56×10² to 9.00×10¹⁰] in model 1, [AOR, 3.69×10⁵; 95% CI, 2.49×10² to 2.71×10¹¹] in model 2) were independently associated with DNS development.

Conclusion

Based on our preliminary results, serum lactate level, serum anion gap, and serum S100B protein level in the emergency department could be informative predictors of DNS development in patients with acute CO poisoning. These markers might have the potential to improve early recognition of DNS in patients with acute CO poisoning.

Dynamic changes and clinical significance of serum S100B protein and glial fibrillary acidic protein in patients with delayed encephalopathy after acute carbon monoxide poisoning

Objective:

To study the dynamic changes and clinical significance of serum S100B protein and glial fibrillary acidic protein (GFAP) in patients with delayed encephalopathy after acute carbon monoxide poisoning (DEACMP).

Methods:

This study was conducted among DEACMP patients who were hospitalized from November 2014 to February 2016. Serum levels of S100B and GFAP in 66 DEACMP patients were measured by ELISA. Changes in patient states were examined dynamically using activities of daily living (ADL) scale, information-memory-concentration test (IMCT) and Hasegawa’s dementia scale (HDS), and compared with those of 64 patients without DE after ACMP.

Results:

Serum S100B [(0.59 ± 0.11) ng/ml] and GFAP [(227.67 ± 12.43) ng/ml] levels of DEACMP group in acute phase were significantly higher than those of ACMP group [(0.48 ± 0.10) ng/ml and (178.91 ± 11.47) ng/ml] and DEACMP group in recovery phase [(0.49 ± 0.12) ng/ml and (179.54 ± 12.32) ng/ml] (all P<0.05). Serum S100B and GFAP levels of DEACMP group were significantly correlated in both acute and recovery phases (r=0.432 in acute phase, P=0.007; r=0.378 in recovery phase, P=0.034). ADL, HDS and IMCT scores of DEACMP group in acute phase were (45.12 ± 3.12), (7.98 ± 1.02) and (9.61 ± 1.41) points respectively, which were significantly different from those of recovery phase [(33.25 ± 3.09), (16.13 ± 1.17) and (19.54 ± 1.43) points respectively] (P<0.05).

Conclusions:

DEACMP was accompanied by secondary brain injury, for which glial activation may be important. Serum S100B and GFAP levels may be related to prognosis.

Plasma copeptin as a predictor of intoxication severity and delayed neurological sequelae in acute carbon monoxide poisoning

The present study was designed to assess the usefulness of measuring plasma levels of copeptin (a peptide co-released with the hypothalamic stress hormone vasopressin) as a biomarker for the severity of carbon monoxide (CO) poisoning and for predicting delayed neurological sequelae (DNS). Seventy-two patients with CO poisoning and 72 sex and age matched healthy individuals were recruited. Plasma copeptin levels were measured on admission from CO poisoning patients and for healthy individuals at study entry by using a sandwich immunoassay. The CO poisoning patients were divided into two groups according to severity (unconscious and conscious) and occurrence of DNS. The mean plasma copeptin levels (52.5±18.5 pmol/L) in the unconscious group were significantly higher than in the conscious group (26.3±12.7 pmol/L) (P<0.001). Plasma copeptin levels of more than 39.0 pmol/L detected CO poisoning with severe neurological symptoms e.g. unconsciousness (sensitivity 84.6% and specificity 81.4%). The plasma copeptin levels were higher in patients with DNS compared to patients without DNS (52.2±20.6 pmol/L vs. 27.9±14.8 pmol/L, P<0.001). Plasma copeptin levels higher than 40.5 pmol/L predicted the development of DNS (sensitivity 77.8%, specificity 82.1%). Plasma copeptin levels were identified as an independent predictor for intoxication severity [odds ratio (OR) 1.261, 95% confidence interval (CI) 1.112-1.638, P=0.002] and DNS (OR 1.313, 95% CI 1.106-1.859, P=0.001). Thus, plasma copeptin levels independently related to intoxication severity and were identified as a novel biomarker for predicting DNS after acute CO poisoning.

The role of S100B protein, neuron-specific enolase, and glial fibrillary acidic protein in the evaluation of hypoxic brain injury in acute carbon monoxide poisoning

The main purpose of this study was to assess the role of S100B protein, neuron-specific enolase (NSE), and glial fibrillary acidic protein (GFAP) in the evaluation of hypoxic brain injury in acute carbon monoxide (CO)-poisoned patients. This cross-sectional study was conducted among the patients with acute CO poisoning who referred to the emergency department in a 1-year period. Serum levels of S100B protein, NSE, and GFAP were determined on admission. A total of 55 CO-poisoned patients (mean age ± standard deviation, 45 ± 20.3 years; 60% women) were included in the study. The control group consisted of 25 healthy adults. The patients were divided into two groups according to whether they were conscious or unconscious. The serum levels of S100B, NSE, and GFAP were higher in patients than that in the control group. There was no significant difference between unconscious and conscious patients with respect to these markers. There was a statistically significant difference between the conscious and unconscious patients and the control group in terms of S100B and NSE levels. There was also a statistically significant difference between the unconscious patients and the control group in terms of GFAP levels. Increased serum S100B, NSE, and GFAP levels are associated with acute CO poisoning. These biomarkers can be useful in assessing the clinical status of patients with CO poisoning.

Potential use of hyperoxygenated solution as a treatment strategy for carbon monoxide poisoning

AIM

Carbon monoxide (CO) poisoning can cause permanent damage in tissues that are sensitive to hypoxia. We explored the feasibility and efficacy of using a hyperoxygenated solution (HOS) to treat severe acute CO poisoning in an animal model.

METHODS

Male Sprague-Dawley rats were subjected to CO poisoning. The HOS was administered into the femoral vein of these rats through a catheter (10 ml/kg). Carboxyhemoglobin (COHb) and blood gases were used to assess the early damage caused by CO poisoning. S100β was measured to predict the development of late cognitive sequelae of CO. The Morris water maze test was performed to assess cognitive function, and Nissl staining was performed to observe histologic change.

RESULTS

The COHb concentrations rapidly decreased at 5 min after the HOS administration; however, the PaO2 and SaO2 in rats treated with HOS increased significantly 5 min after the HOS administration. The S100β concentrations, which increased significantly after CO poisoning, increased at a much slower rate in the rats treated with HOS (HOS group) compared with the rats treated with O2 inhalation (O2 group). The escape latency in the place navigation test was shortened after CO poisoning on days 11-15 and days 26-30, and the swimming time in quadrant 4 in the spatial probe test on days 15 and 30 after CO poisoning was prolonged in the rats treated with HOS injection compared with the rats treated with oxygen inhalation or normal saline injection. The neuronal degeneration in the HOS group was alleviated than that in the CO or O2 group.

CONCLUSION

HOS efficiently alleviates the brain damage in acute CO-poisoned rats and thus may serve as a new way to treat human patients with CO poisoning in clinical practice.

The usefulness of the serum s100b protein for predicting delayed neurological sequelae in acute carbon monoxide poisoning

CONTEXT

Some patients with acute carbon monoxide poisoning will experience delayed neurological sequelae. Several factors associated with delayed neurological sequelae have been reported, but these factors are unsatisfactory for the assessment of unconscious patients.

OBJECTIVE

The aim of this study was to assess the usefulness of the serum S100B protein as a biochemical marker for predicting delayed neurological sequelae.

MATERIALS AND METHODS

In this retrospective study, we evaluated the data for patients who visited an emergency medical center once during a period of 7 months. The enrollment criteria were the diagnosis of acute carbon monoxide poisoning and the measurement of the serum S100B level. A standardized extraction using medical records was performed.

RESULT

A total of 71 patients were enrolled, and 10 patients (14.1%) presented delayed neurological sequelae. The delayed neurological sequelae group had a longer duration of carbon monoxide exposure, a longer duration of loss of consciousness, and a worse mental status (p-value < 0.001). In addition, the S100B protein levels were higher in the delayed neurological sequelae group (0.891 vs. 0.063, p-value < 0.001). Multiple logistic regression analysis showed that only the serum S100B protein level was independently associated with the development of delayed neurological sequelae (OR, 120.594; 95% CI, 4.194-3467.220), and a serum S100B protein level of more than 0.165 μg/L predicted the development of delayed neurological sequelae (sensitivity 90%, specificity 87%).

DISCUSSION AND CONCLUSION

In the present study, the level of serum S100B protein was found to be useful for evaluating acute CO poisoning patients and was found to be an independent predictor of the development of DNS after acute CO poisoning.

The value of initial lactate in patients with carbon monoxide intoxication: in the emergency department

Patients with carbon monoxide (CO) poisoning have been found to have a correlation between initial clinical severity on admission and blood lactate levels. Recently, it is suggested that the lactate level may be a useful prognostic factor in cases study. The purpose of this study was to determine whether lactate levels were associated with the short-term outcome of patients with CO poisoning and identify the characteristics of patients with high initial lactate levels. Eighty patients that presented to the Chonnam National University Hospital after CO poisoning, over 5 years, were enrolled in this retrospective study. Fifty-six (70.0%) patients had high lactate (>2.1 mmo/L) on admission. Thirty-three (41.3%) patients had medical complications and one patient (1.3%) died. The patients with high initial lactate had an altered mental status more frequently, higher WBC, glucose and carboxyhemoglobin (COHb), and lower base deficit on admission. The multivariate analysis showed that lactate was an independent factor associated with serious complications and the need for intensive medical treatment, along with advanced age, WBC, and altered mental status on admission. The results of this study show that the initial lactate was useful for patient prognosis after CO poisoning.

The role of heart-type fatty acid-binding protein in the evaluation of carbon monoxide poisoning in rats

Acute carbon monoxide (CO) poisoning can cause early and persistent damages in tissues sensitive to hypoxia. This study investigated serum heart-type fatty acid-binding protein (H-FABP) levels as a biomarker of acute CO poisoning in rats. The rats were exposed to a mixture of either 3000 (group A) or 5000 (group B) parts per million (ppm) CO in air, or to ambient air (group C, control group). Blood samples were taken just before, immediately after and 6 hours after the exposure, and serum H-FABP and troponin-I levels were measured. The consciousness level was evaluated just after the exposure. The survival rate was monitored for 7 days. Serum H-FABP levels increased just after the CO exposure in both groups A and B. Additionally, H-FABP level was higher in group B than in group A, immediately after the exposure. However, serum troponin-I levels only increased at 6 hours after the CO exposure in groups A and B. Consciousness and survival rates in group B were lower than that in group A. Our results suggest that H-FABP might have potential to be an early and quantitative parameter of clinical severity and prognosis in CO poisoning.

Plasma biomarkers in carbon monoxide poisoning

OBJECTIVES

The severity of acute carbon monoxide (CO) poisoning is often based on non-specific clinical criteria because there are no reliable laboratory markers. We hypothesized that a pattern of plasma protein values might objectively discern CO poisoning severity. This was a pilot study to evaluate protein profiles in plasma samples collected from patients at the time of initial hospital evaluation. The goal was to assess whether any values differed from age- and sex-matched controls using a commercially available plasma screening package.

METHODS

Frozen samples from 63 suspected CO poisoning patients categorized based on clinical signs, symptoms, and blood carboxyhemoglobin level were analyzed along with 42 age- and sex-matched controls using Luminex-based technology to determine the concentration of 180 proteins.

RESULTS

Significant differences from control values were found for 99 proteins in at least one of five CO poisoning groups. A complex pattern of elevations in acute phase reactants and proteins associated with inflammatory responses including chemokines/cytokines and interleukins, growth factors, hormones, and an array of auto-antibodies was found. Fourteen protein values were significantly different from control in all CO groups, including patients with nominal carboxyhemoglobin elevations and relatively brief intervals of exposure.

CONCLUSIONS

The data demonstrate the complexity of CO pathophysiology and support a view that exposure causes acute inflammatory events in humans. This pilot study has insufficient power to discern reliable differences among patients who develop neurological sequelae but future trials are warranted to determine whether plasma profiles predict mortality and morbidity risks of CO poisoning.

S-100beta and neuron-specific enolase levels in carbon monoxide-related brain injury

INTRODUCTION

Carbon monoxide (CO) toxicity may cause persistent injuries in tissues sensitive to hypoxia. Neuropsychiatric sequelae may be observed in about 67% of cases after severe CO exposure.

AIM

The aims of this study were to demonstrate the usefulness of S-100beta and neuron-specific enolase (NSE) in CO intoxications, show the degree of neurological response, and determine the indications for hyperbaric oxygen treatment (HBOT) as biochemical markers.

RESULTS

The S-100beta and NSE levels of the sera of 30 patients were studied upon admittance and at the third and sixth hours. S-100beta levels were found to be high in all 3 analyses. There was no significant change in NSE levels. When the S-100beta levels were compared with Glasgow Coma Scale levels, a strong negative correlation was found for all hours (r = -0.7, -0.8; P = .00). The correlation between S-100beta and carboxyhemoglobin levels at the initial hour was found to be statistically significant (r = 0.4; P = .01). The S-100beta levels in patients receiving HBOT showed a considerable decrease compared with those in patients not receiving the treatment. The same decrease was valid for NSE, although it was insignificant.

CONCLUSION

S-100beta may be useful in evaluating intoxications as an early biochemical marker in CO intoxications, as well as in the differential diagnosis due to other causes, and in determining HBOT indications.

Elevated serum S100B protein and neuron-specific enolase levels in carbon monoxide poisoning

OBJECTIVE

Carbon monoxide (CO) poisoning causes cerebral and generalized hypoxia. This study aimed to assess the possible use of serum glial marker S100B protein and neuron-specific enolase (NSE) as biochemical markers of hypoxic brain damage in acute CO poisoning.

METHODS

Patients with acute CO poisoning admitted to the ED of 2 training hospitals (Ankara, Turkey) were included in this cross-sectional study. Serum levels of S100B and NSE were measured on admission. The patients were divided into 2 groups (unconscious and conscious). Twenty healthy adults were included in the study to serve as controls.

RESULTS

A total of 70 patients poisoned by CO (mean age +/- SD, 36.6 +/- 16.3 years; 64.3% women) were enrolled. Although S100B concentrations were higher in patients than in the control group (P = .018), no significant difference was determined between patient and control groups with respect to NSE concentrations (P = .801). A positive correlation was noted between levels of S100B and NSE (r = 0.388; P = .001). The S100B and NSE values were higher in unconscious patients than in the control group (P = .002 and P = .013, respectively). Furthermore, S100B and NSE values were higher in unconscious vs unconscious patients (P = .047 and P = .005, respectively).

CONCLUSION

Elevated serum S100B and NSE levels were associated with loss of consciousness in CO poisoning in this series of patients. Serum S100B and NSE may be useful markers in the assessment of clinical status in CO poisoning.

Carbon monoxide intoxication: an updated review

Carbon monoxide (CO), a highly toxic gas produced by incomplete combustion of hydrocarbons, is a relatively common cause of human injury. Human toxicity is often overlooked because CO is tasteless and odorless and its clinical symptoms and signs are non specific. The brain and the heart may be severely affected after CO exposure with carboxyhemoglobin (COHb) levels exceeding 20%. Damage occurs because the affinity of hemoglobin for CO is 210 times higher than for O(2). Hypoxic brain damage predominates in the cerebral cortex, cerebral white matter and basal ganglia, especially in the globus pallidus. Diagnosis requires clinical acumen and a high index of suspicion, combined with epidemiological data, clinical examination, analysis of ambient air CO and patient COHb levels; also required are cardiology evaluation including ECG as well as neurological evaluation including brain imaging (CT and/or MRI, MR spectroscopy), and neuropsychological testing. Although immediate O(2) breathing is sometimes an adequate treatment, hyperbaric oxygen therapy (HBO) is favored. Subsequently, only symptomatic therapy is available for the long-term sequelae of CO poisoning.

S100B protein in conscious carbon monoxide-poisoned rats treated with normobaric or hyperbaric oxygen

OBJECTIVE

To evaluate S100B, an astroglial structural protein, during normobaric and hyperbaric oxygen therapy of conscious carbon monoxide (CO)-poisoned rats. So far, the usefulness of hyperbaric oxygen therapy in conscious CO-poisoned patients has been shown with neuropsychological testing. The S100B protein has been demonstrated as a possible biochemical marker and prognostic parameter in CO-poisoned rats.

DESIGN

Randomized, controlled interventional trial.

SETTING

University laboratory.

SUBJECTS

: Male Wistar rats weighing 254 +/- 14 g.

INTERVENTIONS

The rats were exposed to a mixture of 3,000 ppm CO in air for 60 mins. After CO exposure, the first group of eight conscious rats was exposed to ambient air for 30 mins, the second group of six conscious rats was exposed to 100% normobaric oxygen for 30 mins, and the third group of six conscious rats was exposed to 100% hyperbaric oxygen at 3 bars for 30 mins. Blood samples were taken from the jugular vein just before CO exposure and immediately after oxygen therapy. The level of consciousness was evaluated at the end of exposure, and the survival rate was monitored for 14 days. The S100B concentrations were measured with a commercial immunoluminometric assay.

MEASUREMENTS AND MAIN RESULTS

Analyses of differences in S100B levels between different kinds of therapy before and after treatment showed a global significant difference (p = .002). The post hoc test results showed that S100B levels after therapy of the first group treated with ambient air (0.16 +/- 0.07 microg/L) and the second group treated with normobaric oxygen (0.19 +/- 0.05 microg/L) were similar (p = .741), and both of them were significantly different, with much higher values of S100B levels after therapy, from the third group treated with hyperbaric oxygen (0.06 +/- 0.03 microg/L; p = .018 and p = .002, respectively). All the rats survived.

CONCLUSIONS

S100B is elevated in conscious CO-poisoned rats left on ambient air or treated with normobaric oxygen, but not in conscious CO-poisoned rats treated with hyperbaric oxygen.

Toxicity Associated with Carbon Monoxide

Carbon monoxide is an insidious poison that accounts for thousands of deaths each year in North America. Clinical effects maybe diverse and include headache, dizziness, nausea, vomiting,syn-cope, seizures, coma, dysrhythmias, and cardiac ischemia. Children, pregnant women, and patients who have underlying cardiovascular disease are particularly at risk for adverse out-comes. Treatment consists of oxygen therapy, supportive care, and, in selected cases, hyperbaric oxygen therapy.

Carbon monoxide poisoning

CO is an ubiquitous poison with many sources of exposure. CO poisoning produces diverse signs and symptoms that are often subtle and may be easily misdiagnosed. Failure to diagnose CO poisoning may result insignificant morbidity and mortality and permit continued exposure to a dangerous environment. Treatment of CO poisoning begins with inhalation of supplemental oxygen and aggressive supportive care. HBOT accelerates dissociation of CO from hemoglobin and may also prevent DNS. Absolute indications forHBOT for CO poisoning remain controversial, although most authors would agree that HBOT is indicated in patients who are comatose or neurologically abnormal, have a history of LOC with their exposure, or have cardiac dysfunction. Pregnancy with an elevated CO-Hgb level(>15%-20%) is also widely, considered an indication for treatment.HBOT may be considered in patients who have persistent symptoms despite NBO, metabolic acidosis, abnormalities on neuropsychometric testing, or significantly elevated levels. The ideal regimen of oxygen therapy has yet to be determined, and significant controversy exists regarding HBOTtreatment protocols. Often the local medical toxicologist, poison control center, or hyperbaric unit may assist the treating physician with decisions regarding therapy.