Immunosuppressive effect of isopropanol: down-regulation of cytokine production results from the alteration of discrete transcriptional pathways in activated lymphocytes.

Isopropanol (IPA) is widely used in household applications and constitutes a leading cause of acute alcohol intoxication second only to ethanol. Although the effects of ethanol on the immune system have been extensively studied, far fewer data are available on IPA. Given the structural similarity between the two molecules, we hypothesized that IPA could as well have immunomodulatory properties. We report here that acute IPA exposure is detrimental to human T lymphocyte and NK cell activity in vitro in concentrations as low as 0.08-0.16% (13-26 mM). IPA treatment did not affect receptor-mediated early signaling but had a reproducible and dose-dependent effect on the nuclear translocation of NFAT and AP-1. Furthermore, we show in a model of acute IPA intoxication that animals became immunosuppressed as judged by their reduced ability to release IL-2 and IFN-gamma in the serum in response to staphylococcal enterotoxin B. This effect was also associated to the down-regulation of TNF-alpha production and was sufficiently strong to rescue susceptible animals from enterotoxin-induced toxic shock. Our results suggest that IPA is potentially immunosuppressive to the adaptive and innate immune system and have broad significance given the exposure of the general population to this ubiquitous chemical.

Sustained low-efficiency dialysis (SLED) therapy following ingestion of isopropanol in a pediatric patient.

Introduction: Cardiovascular collapse due to large ingestions of isopropanol is rare. We report a case of a pediatric patient who had severe CNS and respiratory depression and cardiovascular collapse and was not hemodynamically stable enough to undergo hemodialysis.Case report: A 14-year-old 50 kg male was initially reported to have ingested an unknown amount of HEET® gas line antifreeze about 1 h prior to emergency department (ED) arrival. Despite severe CNS and respiratory depression and cardiovascular collapse, the patient was not initially acidotic. The patient did have an elevated osmolar gap. Approximately 6 h post-ingestion relatives updated the history to reflect that the product was in fact called ISO-HEET® which contains 99% isopropanol. Based on these concerns, a serum isopropanol and acetone levels were obtained that resulted at 475 and 75 mg/dL, respectively. Nephrology was consulted and it was decided to start the patient on sustained low-efficiency dialysis (SLED) which commenced 11 h post-ingestion. Serum and ultrafiltrate concentrations for isopropanol and acetone decreased to normal range over the course of SLED therapy.Discussion: SLED was instituted in this patient primarily for the treatment of elevated serum lactate, isopropanol, and acetone concentrations. The patient's systemic clearance was calculated as 26.9 mL/min. During SLED therapy, the patient was able to clear isopropanol and acetone at 41.21 mL/min and 29.74 mL/min, respectively. SLED therapy is a viable treatment option when a patient is hemodynamically unstable and hemodialysis is not an option.

Postmortem diagnosis of ketoacidosis: Levels of beta-hydroxybutyrate, acetone and isopropanol in different causes of death.

Data from 496 autopsy cases with positive beta hydroxybutyrate (BHB), acetone or isopropanol in blood were investigated. The cases were divided into different groups according to cause of death. Cases with cause of death due to diabetic ketoacidosis (DKA, n=54) had the highest levels of BHB (median 1085mg/L) and acetone (median 330mg/L). Cases with cause of death due to alcoholic ketoacidosis (AKA, n=57) had high levels of BHB (median 500mg/L) and acetone (median 110mg/L). Cases with cause of death due to hypothermia (n=12) had similar BHB and acetone levels as the AKA group (median BHB 520mg/L and acetone 80mg/L). Cases with cause of death due to isopropanol intoxication (n=17) had high levels of isopropanol (median 430mg/L) and acetone (330mg/L), but undetected or low levels of BHB. Cases with cause of death due to other than the above mentioned (n=349) had median BHB levels of 100mg/L and median acetone levels of 20mg/L. BHB analysis is crucial for the diagnosis of postmortem ketoacidosis, since it is the main marker of ketoacidosis and helps distinguish between different causes of death. Acetone levels correlate with BHB levels in endogenous ketoacidosis, so acetone can be used as an initial screening marker to identify cases where BHB analysis should be performed, but positive acetone threshold should be maximum 20mg/L. Positive BHB is proof of endogenous ketoacidosis, whereas negative BHB indicates isopropanol intoxication or postmortem acetone/isopropanol formation by microorganisms in cases of decomposition. There is no correlation between BHB and the postmortem interval, and no sign of postmortem formation, so BHB analysis is useful even in cases of severe decomposition.

Isopropyl alcohol ingestion presenting as pseudorenal failure due to acetone interference.

Isopropyl alcohol is a relatively common source of clinical intoxication. It is usually suspected when a patient presents with high serum or urine ketones and a high osmolar gap without acidosis. Acute renal failure due to isopropyl alcohol ingestion is rare. We describe a patient with isopropyl alcohol ingestion who presented with renal failure, but with a false elevation of serum creatinine secondary to interference by acetone with the colorimetric assay for creatinine. We highlight the use of blood gas analyzers, which use an enzymatic assay, thus avoiding acetone interference, as a quick method to correctly estimate the serum creatinine concentration and avoid labeling the patient as having acute renal failure.

[Acute intoxication with isopropanol]. / Akute Intoxikation mit Isopropanol.

Isopropanol is an ingredient of commonly used industrial and household agents. Intoxication can occur unintentionally, in suicide attempts or by alcohol abusers when used as a substitute for ethanol. Symptoms involve the gastrointestinal tract, the central nervous system, and the cardiovascular system at higher doses. Mortality is especially high in patients with deep coma and marked hypotension. This report describes a case of life-threatening isopropanol intoxication of a prison inmate successfully treated by haemodialysis.

Methionine availability in plasma of dairy cows supplemented with methionine hydroxy analog isopropyl ester.

Adequate Met supply is especially important in the dairy cow for milk protein synthesis. Because of insufficient Met contents in the most frequently used feed-stuffs, Met becomes limiting in the diet of the dairy cow. To restore the amino acid balance of the diet and consequently to optimize lactation performance, Met must be supplied in a protected form because of its high degradability as a free amino acid by rumen microorganisms. A new chemical derivative of Met, the isopropyl ester of the 2-hydroxy-4-(methylthio)-butanoic acid (HMBi) was tested for its metabolic fate by following the evolution of plasma concentrations of its metabolites (2-hydroxy-4-(methylthio)-butanoic acid (HMB), Met, isopropyl alcohol, and acetone) after spot-dose supplementation (50 g Met equivalent) to 15 cows. Results indicated that HMBi would be quickly absorbed and hydrolyzed into HMB and isopropyl alcohol, and then converted to Met and acetone, respectively. In our experimental conditions, the Met availability for cows was estimated to be 48.34 +/- 2.05% using a calibration curve established by modeling the area under the curve response to increasing doses of Met supplied as Smartamine M, whose bioavailability (80%) is considered the reference value. Plasma kinetics and bioavailability of Met were compared between HMBi and Smartamine M in the same cows. Comparison of the kinetics suggests that HMBi would be absorbed through the rumen wall providing good protection against rumen microorganisms. It can thus be concluded that HMBi is a new source of Met for ruminants with an acceptable bioavailability.

Dermal absorption of isopropyl alcohol from a commercial hand rub: implications for its use in hand decontamination.

Isopropyl alcohol-containing hand rubs are widely used in healthcare for hand decontamination. Ten healthy adult volunteers applied a commercially available isopropyl alcohol-containing hand rub to their hands every 10 min over a 4 h period. Blood isopropyl alcohol levels were measured at the beginning and end of the study. At the end of the study, measurable blood isopropyl alcohol levels (range 0.5-1.8 mg/l) were recorded in nine subjects. We confirmed that isopropyl alcohol could be absorbed through the intact skin of adult humans. The social and medical implications are discussed.

Incidence of alcohol dependence among drunken drivers.

To discriminate 'alcoholics' and 'non-alcoholics', individual Alc-Indices (determined by methanol, acetone, 2-propanol, gamma-GT and CDT-concentrations) were calculated in a collective of 327 alcohol-impaired drivers with regard to the blood alcohol concentration, the time of the event and the age of the drivers. Applying this new defined Alc-Index, 48% of the drivers investigated could be characterised as alcohol dependent. The prevalence of alcoholics among individuals with blood alcohol concentrations (BAC) higher than 1.9per thousand was more than 80%. The diagnostic value of alcohol concentrations for the recognition of 'alcoholics', considering the legal limit in Germany (1.1per thousand) as well as statistically calculated limits, were compared to the Alc-Index.

Concentration of ethanol and other volatile compounds in the blood of acutely poisoned alcoholics.

The presence of volatile compounds, such as acetone, acetaldehyde, methanol, ethanol, isopropanol, and n-propanol, in the blood of 169 acutely poisoned alcoholics was determined. The clinical diagnosis of addiction was made on the basis of a patient interview as well as physical, psychological, and psychiatric examination. At the time of the patients' admission to the clinic, the mean concentration of ethanol in blood was 3.14 +/- 1.10 g/l and its elimination rate in the studied group was 0.27 +/- 0.08 g/kg/hr, an elimination rate significantly higher (P <.001) than that of social drinkers, which averages to 0.014 +/- 0.04 g/kg/h. The presence of other volatile compounds in the blood of alcohol-addicted patients is common. The calculated elimination rate constant of methanol was about 0.2 h(-1). This rate seems to indicate that, in heavy drinkers, the elimination of methanol may be relatively fast even if the ethanol concentration is above 1 g/l. The elimination of other volatile compounds can be accelerated by large doses of ethanol, although it is not correlated with actual blood ethanol level. Moreover, in most of the blood samples with a methanol concentration below 10 mg/l, the measured concentration of acetone was below 7 mg/l and that of isopropanol was below 2 mg/l.

Simultaneous detection and quantitation of diethylene glycol, ethylene glycol, and the toxic alcohols in serum using capillary column gas chromatography.

Determination of toxic glycols and alcohols in an emergency setting requires a rapid yet accurate and reliable method. To simultaneously determine diethylene glycol (DEG) along with ethylene glycol, methanol, isopropanol, acetone, and ethanol, we modified a previously developed gas chromatographic (GC) method. The system used a Hewlett-Packard 6890 GC with EPC, a Gooseneck splitless liner, and an Rtx-200 capillary column (30 m x 0.53-mm i.d., 3 mm). After serum samples were deproteinized using ultrafiltration (Millipore Ultrafree-MC), 1 mL of the protein-free filtrate was manually injected into the GC. Internal standards for alcohols (and acetone) and glycols were n-propanol and 1,3-butanediol, respectively. All compounds eluted within 3.5 min (linear temperature gradient from 40 to 260 degrees C); total run time was 6.5 min. Limit of detection and linear range for all compounds were 1 or 2.5 mg/dL and 0-500 mg/dL, respectively. In addition, there was no interference from propionic acid, propylene glycol, and 2,3-butanediol. The modifications in the equipment and temperature program allowed increased resolution and thus, detection and reliable quantitation of DEG and other common toxic glycols and alcohols of clinical interest.

Very unusual ethanol distribution in a fatality.

A 48-year-old man with an extensive history of alcoholism was found dead at home. He was lying face down on a carpet. There was evidence of gastric aspiration at autopsy and histologic examination. The distribution of ethanol was very unusual (concentrations in mg/100 mL or mg/100 g): femoral blood, 257 and 273 (two samples); heart blood, 643; vitreous humor, 763; urine, 84; bile, 616; liver, 250; and gastric, 4660 (2470 mg/53 g). In addition, this man ingested isopropanol, and, according to the history, may also have ingested acetone in the form of nail polish remover. The distribution of both isopropanol and acetone was as expected, which was approximately in proportion to the aqueous content of the respective tissues. It is proposed that agonal or postmortem aspiration of the ethanol-rich vomitus and postmortem fermentation could account for the apparently elevated concentrations of ethanol in heart blood and bile. The elevated vitreous ethanol could be explained if ethanol diffused across the eye in the agonal phase or postmortem from gastric aspirate in the carpet. The relatively low urinary ethanol concentration would be consistent with a recent binge-drinking episode, which allowed only a limited time period for excretion into an already partially full, but relatively ethanol-free, bladder.

Detection of isopropyl alcohol in a patient with diabetic ketoacidosis.

A 29-year-old man presented to the Emergency Department with acute mental status changes. He was unable to give a history. He was found to be in diabetic ketoacidosis, although his family reported no prior history of diabetes. A toxic exposure work-up revealed the presence of isopropyl alcohol in the patient's blood. His condition improved with treatment of the ketoacidosis, and he subsequently denied any exposure to isopropyl alcohol prior to presentation to the hospital. This case provides further support to a growing body of evidence that the detection of isopropyl alcohol may not represent an acute ingestion but, rather, a byproduct of acetone metabolism in certain disease states.

Comparison of blood-ethanol concentration in deaths attributed to acute alcohol poisoning and chronic alcoholism.

Ethanol concentrations were measured in femoral venous blood in deaths attributed to acute alcohol poisoning (N = 693) or chronic alcoholism (N = 825), according to the forensic pathology report. Among acute alcohol poisonings were 529 men (76%) with mean age 53 years and 164 women (24%) with mean age 53 years. In the chronic alcoholism deaths were 705 men (85%) with mean age 55 years and 120 women (15%) with mean age 57 years. The blood-ethanol concentrations were not related to the person's age (r = -0.17 in acute poisonings and r = -0.09 in chronic alcoholism). The distribution of blood-ethanol concentrations in acute poisoning cases agreed with a normal or Gaussian curve with mean, median, standard deviation, coefficient of variation, and spread of 0.36 g/100 mL, 0.36 g/100 mL, 0.086 g/100 mL, 24% and 0.074 to 0.68 g/100 mL, respectively. The corresponding concentrations of ethanol in chronic alcoholism deaths were not normally distributed and showed a mode between 0.01 and 0.05 g/100 mL and mean, median, and spread of 0.172 g/100 mL, 0.150 g/100 mL, and 0.01 to 0.56 g/100 mL, respectively. The 5th and 95th percentiles for blood-ethanol concentration in acute poisoning deaths were 0.22 and 0.50 g/100 mL, respectively. However, these values are probably conservative estimates of the highest blood-ethanol concentrations before death owing to metabolism of ethanol until the time of death. In 98 chronic alcoholism deaths (12%) there was an elevated concentration of acetone in the blood (>0.01 g/100 mL), and 50 of these (6%) also had elevated isopropanol (>0.01 g/100 mL). This compares with 28 cases (4%) with elevated blood-acetone in the acute poisoning deaths and 22 (3%) with elevated blood-isopropanol. We offer various explanations for the differences in blood-ethanol and blood-acetone in acute poisoning and alcoholism deaths such as chronic tolerance, alcohol-related organ and tissue damage (cirrhosis, pancreatitis), positional asphyxia or suffocation by inhalation of vomit, exposure to cold coupled with alcohol-induced hypothermia, as well as various metabolic disturbances such as hypoglycemia and ketoacidosis.

Fatal diabetic ketoacidosis and antipsychotic medication.

Hyperglycemia and new onset diabetes have been described with certain antipsychotic medications and some of the initial presentations are fatal diabetic ketoacidosis (DKA). We report 17 deaths due to DKA in psychiatric patients treated with second generation antipsychotic medications. Death certificates and toxicology data were searched for DKA and hyperglycemia. We reviewed the medical examiner records which included the autopsy, toxicology, police, and medical examiner investigators' reports. The decedents ranged in age from 32 to 57 years (average 48 years). There were 15 men and two women. The immediate cause of death was DKA in all. The psychiatric disorders included: 10 schizophrenia, three bipolar/schizophrenia, two bipolar, and two major depression. The most frequent atypical antipsychotic medications found were quetiapine and olanzapine followed by risperidone. In 16 deaths, we considered the medication as primary or contributory to the cause of death.

Ketoacidosis and trace amounts of isopropanol in a chronic alcoholic patient.

BACKGROUND: Alcohol ketoacidosis is a frequently missed diagnosis, but is well described in the literature. We present a case of ketoacidosis, likely alcohol ketoacidosis, in a 40 y-old chronic alcoholic patient. The detection of trace serum isopropanol prompted a discussion of alcohol ketoacidosis versus toxic isopropanol ingestion or a combination of both, including comparisons with citations in current literature. METHODS: The automated instruments used to analyze the patient's urine, blood, and serum samples are described. RESULTS: The initial impression was severe metabolic acidosis with an increased anion gap and normal serum glucose and whole blood lactate. Testing for potential toxic ingestions detected only increased serum acetone and trace serum isopropanol. A urinalysis positive for ketones and an increased serum ß-hydroxybutyrate concentration clenched the diagnosis of ketoacidosis. CONCLUSION: Ketoacidosis with an increased anion gap in the absence of hyperglycemia or glycosuria in a chronic alcoholic patient should prompt the evaluation for alcohol ketoacidosis. Trace serum isopropanol may be worrisome for a toxic ingestion, but this finding in severe ketoacidosis may be explained by the reversible action of the enzyme alcohol dehydrogenase. Markedly increased serum isopropanol with a low serum acetone:isopropanol ratio would be more indicative of a toxic isopropanol ingestion.

Repeated intoxication presenting with azotemia, elevated serum osmolal gap, and metabolic acidosis with high anion gap: differential diagnosis, management, and prognosis.

A man with a history of alcoholism presented on two different occasions with mental changes, clinical signs of volume depletion, elevated serum osmolal gap, metabolic acidosis with high anion gap, metabolic alkalosis, hyponatremia, and azotemia after binge drinking of only ethanol. In both episodes, the serum contained ethanol, acetone, and 2-propanol (isopropanol), but no methanol or ethylene glycol. In the first episode, the rates of excretion of acetoacetate and 3-hydroxybutyrate in the urine were greatly increased. Volume repletion was the only treatment. In both episodes, azotemia and metabolic acidosis were rapidly reversed, while modest metabolic alkalosis was noted after treatment. The triad of azotemia, elevated osmolal gap, and high anion gap metabolic acidosis, which characterizes intoxication with methanol or ethylene glycol, can also develop in alcoholic ketoacidosis (AKA), an entity with substantially different management and outcome. Finding 2-propanol in the serum of patients with AKA indicates either concomitant 2-propanol ingestion or formation of 2-propanol from acetone.