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BACKGROUND: Sugammadex prolongs activated partial thromboplastin time (aPTT) and prothrombin time (PT) suggestive of anticoagulant effects. To pinpoint its presumed anticoagulant site of action, the authors assessed Sugammadex's impact on a panel of coagulation assays. METHODS: Sugammadex, Rocuronium, Sugammadex and Rocuronium combined, or saline were added to blood samples from healthy volunteers and analyzed using plasmatic (i.e., aPTT, thrombin time, and fibrinogen concentration) (n = 8 each), PT (quick), activities of plasmatic coagulation factors, and whole blood (extrinsically and intrinsically activated thromboelastometry) assays (n = 18 each). Furthermore, dose-dependent effects of Sugammadex were also assessed (n = 18 each) in diluted Russel viper venom time (DRVVT) assays with low (DRVVT1) and high (DRVVT2) phospholipid concentrations and in a highly phospholipid-sensitive aPTT assay. RESULTS: Sugammadex increased PT (+9.1%; P < 0.0001), aPTT (+13.1%; P = 0.0002), and clotting time in extrinsically (+33.1%; P = 0.0021) and intrinsically (+22.4%; P < 0.0001) activated thromboelastometric assays. Furthermore, activities of factors VIII, IX, XI, and XII decreased (-7%, P = 0.009; -7.8%, P < 0.0001; -6.9%, P < 0.0001; and -4.3%, P = 0.011, respectively). Sugammadex dose-dependently prolonged both DRVVT1 and the highly phospholipid-sensitive aPTT assays, but additional phospholipids in the DRVVT2 assay almost abolished these prolongations. Thrombin time, a thromboelastometric thrombin generation assay, clot firmness, clot lysis, fibrinogen concentration, and activities of other coagulation factors were unaltered. Rocuronium, Sugammadex and Rocuronium combined, and saline exerted no effects. CONCLUSION: Sugammadex significantly affects various coagulation assays, but this is explainable by an apparent phospholipid-binding effect, suggesting that Sugammadex`s anticoagulant effects are likely an in vitro artifact.
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Anticoagulantes/farmacologia , Artefatos , gama-Ciclodextrinas/farmacologia , Adulto , Testes de Coagulação Sanguínea/estatística & dados numéricos , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Masculino , Valores de Referência , SugammadexRESUMO
Background: Post-acute sequelae of COVID-19 (PASC) comprise a broad spectrum of symptoms such as fatigue, general weakness, compromised attention and sleep or anxiety disorders. PASC represents a medical and socio-economic challenge. Objectives: Our study evaluated cytokines (IL-1ß, IL-6 and TNFα) and cortisol levels in a cohort of typical patients with PASC, suffering concentration problems, fatigue and difficulties finding words. Design: This was a prospective cohort study. Four groups were analysed and compared: those who had never contracted SARS-CoV-2 (n = 13), infected but had no PASC (n = 34), infected with former PASC that resolved (n = 40) and patients with ongoing PASC after infection (n = 91). Methods: Cytokine and cortisol serum levels were determined in patients' blood samples. Results: Cytokine levels of IL-1ß, IL-6, TNFα and cortisol levels did not differ between groups analysed. Conclusion: This may indicate a non-organic/psychosomatic genesis of PASC; further studies are needed to elucidate the underlying causes of PACS, and non-organic causes should not be overlooked.
Without clear biological markers for people who will continue to present with post-acute sequelae of COVID-19 (PASC) should we now focus on psychological factors? Many people across the globe are still suffering from post-acute sequelae of COVID-19 (PASC), commonly called post-COVID. Typical symptoms of PASC include severe tiredness (fatigue), concentration deficits (brain fog) or difficulty finding words. We need a better understanding of how these symptoms arise to find ways to help patients. Our team of researchers set out to explore this. We posed the question: could measurements of immune system activity provide an identifier for people who are susceptible to post-COVID? The participants in our study were divided into four groups: 1. A group of 13 people who had never contracted SARS-CoV-2. 2. A group of 34 people who had been infected with SARS-CoV-2 but had no PASC. 3. A group of 40 people who had been infected with SARS-CoV-2 and had already suffered from PASC that had now resolved. 4. A group of 91 people who were no longer sick with COVID-19 but were still suffering from PASC. Serum samples from all participants were taken to measure cytokine and cortisol levels. People with PASC could not be identified by testing their blood samples for cytokines (IL-1ß, IL-6, TNFα) or cortisol. No difference between the four groups was found on any marker. Measuring these cytokines or cortisol is, therefore, unlikely to be useful in predicting which patients will suffer from PASC. Continuation of symptoms long after COVID-19 has passed is distressing for many people worldwide. Psychological factors may play a role and need to be studied further in order to help this patient population.
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Background: Deviations in serum creatinine (SCr), due to its determination using a Jaffe or an enzymatic method, have an effect on kidney disease detection and staging. It is not yet clear how large this effect is in kidney transplant recipients (KTRs). SCr measurement differences are of particular importance here to evaluate the graft function. Methods: The results of all parallel SCr measurements (Jaffe and enzymatic method) of adult outpatient KTRs in the same serum sample at the University Hospital Essen (Germany) between January 2020 and October 2023 were evaluated. A Bland-Altman plot with 95% limits of agreement (LoA) was used to assess the difference between the Jaffe and the enzymatic SCr (eSCr). For all patients, we used the CKD-EPI 2009 and EKFC formula, and for patients ≥ 70 years, we also used the BIS1 formula for the determination of eGFR. Results: A total of 12,081 parallel SCr measurements from 1243 KTRs were analyzed, where 61% were male and the median age was 53 years. On average, Jaffe SCr was 0.03 mg/dL higher than eSCr (LoA -0.16; 0.21 mg/dL). On average, the eGFR determined by Jaffe SCr was 1.9 mL/min/1.73 m2 lower than the eGFR determined by eSCr (LoA -9.5; 5.7 mL/min/1.73 m2). The comparison of eGFR between the two SCr methods revealed a different CKD stage in 1589 (13%) of all analyzed measurements, most frequently between G2/G3a (41%) and G3a/G3b (24%). When using the EKFC and BIS1 formulas, there were approximately the same number of measurements leading to a different CKD stage. Conclusions: In more than every tenth SCr determination in outpatient KTRs, the difference between the Jaffe and enzymatic methods had an influence on the assignment to a CKD stage. This effect was comparably pronounced for all eGFR formulas applied.
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BACKGROUND: Malignant ascites commonly occurs in advanced or recurrent stages of epithelial ovarian cancer during peritoneal carcinomatosis and is correlated with poor prognosis. Due to its complex composition of cellular and acellular components malignant ascites creates a unique tumor microenvironment, which mediates immunosuppression and promotes progression of disease. However, the immunosuppressive mechanisms remain poorly understood. METHODS: In the present study, we explored the antitumor activity of healthy donor NK and T cells directed against ovarian cancer cells in presence of malignant ascites derived from patients with advanced or recurrent peritoneal carcinomatosis. A wide range of methods was used to study the effect of ascites on NK and T cells (FACS, ELISA, EliSpot, qPCR, Live-cell and confocal microscopy, Western blot and electrolyte flux assays). The ascites components were assessed using quantitative analysis (nephelometry, potentiometry and clinical chemistry) and separation methods (dialysis, ultracentrifugal filtration and lipid depletion). RESULTS: Ascites rapidly inhibited NK cell degranulation, tumor lysis, cytokine secretion and calcium signaling. Similarly, target independent NK and T cell activation was impaired in ascites environment. We identified imbalanced electrolytes in ascites as crucial factors causing extensive immunosuppression of NK and T cells. Specifically, high sodium, low chloride and low potassium content significantly suppressed NK-mediated cytotoxicity. Electrolyte imbalance led to changes in transcription and protein expression of electrolyte channels and impaired NK and T cell activation. Selected inhibitors of sodium electrolyte channels restored intracellular calcium flux, conjugation, degranulation and transcript expression of signaling molecules. The levels of ascites-mediated immunosuppression and sodium/chloride/potassium imbalance correlated with poor patient outcome and selected molecular alterations were confirmed in immune cells from ovarian cancer patients. CONCLUSION: Our data suggest a novel electrolyte-based mechanism of immunosuppression in malignant ascites of patients with peritoneal carcinomatosis. We show for the first time that the immunosuppression of NK cytotoxicity in coculture assays is correlated to patient poor survival. Therapeutic application of sodium channel inhibitors may provide new means for restoring immune cell activity in ascites or similar electrolyte imbalanced environments.
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Neoplasias Ovarianas , Neoplasias Peritoneais , Humanos , Feminino , Ascite , Cloretos , Linfócitos T , Potássio , Microambiente TumoralRESUMO
The COVID-19 mRNA vaccine is the first mRNA vaccine approved for human administration by both the U.S. Food and Drug Administration and the European Medicines Agency. Studies have shown that the immune response and the decay of immunity after vaccination with the COVID-19 vaccines are variable within a population. Host genetic factors probably contribute to this variability. In this study, we investigated the effect of the single-nucleotide polymorphisms rs12252 and rs34481144 in the interferon-induced transmembrane protein (IFITM) 3 gene on the humoral immune response after vaccination against COVID-19 with mRNA vaccines. Blood samples were collected from 1893 healthcare workers and medical students at multiple time points post-vaccination and antibody titers against the SARS-CoV-2 S1 protein receptor binding domain were determined at all time points. All participants were genotyped for the rs34481144 and rs12252 polymorphisms in the IFITM3 gene. After the second and third vaccinations, antibody titer levels increased at one month and decreased at six months (p < 0.0001) and were higher after the booster vaccination than after the basic immunization (p < 0.0001). Participants vaccinated with mRNA-1273 had a higher humoral immune response than participants vaccinated with BNT162b2. rs12252 had no effect on the antibody response. In contrast, carriers of the GG genotype in rs34481144 vaccinated with BNT162b2 had a lower humoral immune response compared to A allele carriers, which reached statistical significance on the day of the second vaccination (p = 0.03) and one month after the second vaccination (p = 0.04). Further studies on the influence of rs12252 and rs34481144 on the humoral immune response after vaccination against COVID-19 are needed.
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Background: Serum creatinine (SCr), mainly determined by the Jaffe or an enzymatic method, is the central marker to assess kidney function. Deviations between these two methods may affect the diagnosis and staging of acute kidney injury (AKI) and chronic kidney disease (CKD). Methods: The results of the first parallel SCr measurement (Jaffe and enzymatic method) of adult in- and outpatients in the same serum sample at the University Hospital Essen (Essen, Germany) between 2020-2022 were retrospectively evaluated. A Bland-Altman plot with 95% limits of agreement (LoAs) was used to assess the difference between the Jaffe and the enzymatic SCr (eSCr) method. We used the 2009 Chronic Kidney Disease Epidemiology Collaboration equation for determination of estimated glomerular filtration rate (eGFR) according to the Kidney Disease: Improving Global Outcomes guidelines. Results: A total of 41 144 parallel SCr measurements were evaluated. On average, Jaffe SCr was 0.07 mg/dl higher than eSCr (LoA -0.12; 0.25 mg/dl). In 19% of all cases there was a different CKD stage when comparing eGFR between both SCr methods, of which 98% resulted in a more severe CKD stage determined with Jaffe SCr. In 1.6% of all cases Jaffe SCr was ≥0.3 mg/dl higher than eSCr. Conclusion: The present study showed that methods of SCr measurement may affect both the diagnosis and staging of AKI and CKD. This must be taken into account when interpreting measurements of renal function in everyday clinical practice, but also when planning and comparing studies on renal diseases. One should therefore stay with one method for SCr measurement, preferably with the enzymatic method.
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Thrombolysis is the only effective pharmaceutical therapy in acute ischemic stroke in humans but has a high risk of intracerebral hemorrhage. We aimed to establish an animal model to study changes of coagulation and fibrinolytic parameters during thromboembolic ischemic stroke and thrombolysis with recombinant tissue plasminogen activator (rt-PA). We used a thromboembolic stroke model in the rat. Animals were treated with rt-PA thrombolysis (n=10) and compared with untreated (n=10), sham operated (n=10) and control animals (n=20). Coagulation parameters (APTT, PT, TT, fibrinogen, AT III, TAT) and fibrinolytic parameters (t-PA antigen concentration, t-PA activity, PAI-1 concentration, PAI activity, plasminogen, antiplasmin) were measured at two time points (2.5 and 5h after stroke induction) with a battery of commercially available test kits. We observed an (1) initiation of coagulation and inhibition of fibrinolysis by the operation procedure itself, (2) simultaneous activation of fibrinolysis and its inhibitors after stroke induction and (3) potent initiation of fibrinolysis and consumption of fibrinolysis inhibitors after rt-PA therapy of stroke. We established a model system to monitor coagulation and fibrinolysis during thrombolytic therapy of stroke in the rat. This model may be used to study the influence of these parameters on hemorrhagic stroke transformation and outcome in experimental stroke in future.
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Coagulação Sanguínea/efeitos dos fármacos , Fibrinólise/efeitos dos fármacos , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/métodos , Animais , Modelos Animais de Doenças , Masculino , Plasminogênio/metabolismo , Ratos , Ratos Wistar , Acidente Vascular Cerebral/etiologia , Tromboembolia/complicações , Fatores de Tempo , Ativador de Plasminogênio Tecidual/uso terapêuticoRESUMO
BACKGROUND: Stenting-related myocardial injury has been recognized as a frequent and prognostically important event, the extent of which depends on microcirculatory impairment in association with platelet aggregation, inflammation, and increased oxidative stress. Recent studies underscored the non-lipid-lowering effects of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) with antithrombotic, antiinflammatory, and antioxidative aspects. Thus, we tested the hypothesis that preprocedural statin therapy is associated with a reduction in the extent of stenting-related myocardial injury. METHODS AND RESULTS: We stratified 296 consecutive patients who were undergoing stenting of a de novo stenosis according to the preprocedural status of statin therapy (229 statin-treated and 67 control patients). Incidence of periprocedural myocardial injury was assessed by analysis of creatine kinase (CK; upper limit of normal [ULN] 70 IU/L for women, 80 IU/L for men) and cardiac troponin T (cTnT; bedside test; threshold 0.1 ng/mL) before and 6, 12, and 24 hours after the intervention. Relative to control patients, the incidence of CK elevation >3x ULN was more than 90% lower in statin-treated patients (0.4% versus 6.0%, P=0.01). Statin therapy was the only factor independently associated with a lower risk of CK elevation >3x ULN (OR: 0.08, 95% CI: 0.01 to 0.75; P=0.03). The overall incidences of CK and cardiac troponin T elevation were slightly lower in statin-treated than in control patients (14.4% versus 20.9%, P=0.3, and 17.9% versus 22.4%, P=0.5, respectively). CONCLUSIONS: Preprocedural statin therapy is associated with a reduction in the incidence of larger-sized, stenting-related myocardial infarctions. Prospective, randomized trials are warranted to further assess this cardioprotective effect of statins in coronary intervention.
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Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Infarto do Miocárdio/prevenção & controle , Biomarcadores/análise , Cardiotônicos/uso terapêutico , Estenose Coronária/cirurgia , Creatina Quinase/análise , Intervalo Livre de Doença , Eletrocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Miocárdio/química , Miocárdio/enzimologia , Stents/efeitos adversos , Resultado do Tratamento , Troponina T/análiseRESUMO
BACKGROUND: Urinary excretion of the low molecular weight protein cystatin C is a marker of renal disorders and a good predictor of the severity of acute tubular necrosis. We evaluated the measurement of urinary cystatin C and determined its reference range. METHODS: Measurement of urinary cystatin C by particle-enhanced nephelometric immunoassay (PENIA) in 102 patients with various renal disorders and 133 healthy controls. We assessed the influence of pH and temperature, interferences on urinary cystatin C measurement, as well as cystatin C adsorption to plastic. RESULTS: The upper reference value for urinary cystatin C was 0.28 mg/L, independent of age and gender. Accuracy and linearity (r(2)=0.996) were excellent. Intra- and inter-assay precision were < or =4.8% and < or =5.2%, respectively. Albumin (< or =160 g/L), bilirubin (< or =500 micromol/L) and haemoglobin (< or =210 micromol/L) did not show interferences. Urinary cystatin C was stable, at urine pH> or =5, at -20 degrees C and 4 degrees C for 7 days, and at 20 degrees C for 48 h. Freezing and thawing did not influence urinary cystatin C concentration. There was no adsorption of cystatin C to plastic. CONCLUSION: Urinary cystatin C measurement by PENIA is precise. High stability and no interference add to the practicability of urinary cystatin C as a routine biochemical test.
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Cistatinas/urina , Nefropatias/urina , Adulto , Idoso , Calibragem , Cistatina C , Feminino , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Nefelometria e Turbidimetria , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Smoking accounts for more than 5 million years of potential life lost per year in the US alone. Leading causes of smoking attributable mortality are acute atherothrombotic complications of coronary heart disease (CHD). Smoking cessation is a key issue in preventive medicine, but quantitative data on its benefit for the coronary arteries are sparse. METHODS: The Heinz Nixdorf Recall Study is an ongoing population-based, prospective cohort study, with 4814 participants aged 45-74 years (49.8% men). Baseline data of 4078 participants without history of established coronary heart disease or stroke are included in this report. Electron beam-computed tomography allows for non-invasive quantification of coronary artery calcium (CAC). We estimate the risk-related ageing of coronary arteries from multivariable regression of CAC on smoking behavior, sex, age and risk factors. RESULTS: Smoking 20 cigarettes per day since the age of 16 is associated with a CAC burden which is found in a person 10 years older who has never smoked (both sexes). Smoking cessation at 45, 55 or 65 leads to CAC at the age of 75 that would have been reached 9, 6 or 3 years earlier, respectively, had smoking been continued. CONCLUSIONS: In individuals without overt CHD, present smokers are about 10 years older in 'coronary artery age' than never smokers. The accumulation of CAC is accelerated by smoking and slows down after smoking cessation, but advanced CAC is persistent for a long period. These quantitative findings strongly support smoking cessation measures as early as possible, to prevent accelerated arterial ageing.
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Aterosclerose/diagnóstico , Aterosclerose/prevenção & controle , Doença das Coronárias/prevenção & controle , Doença das Coronárias/terapia , Abandono do Hábito de Fumar , Fumar/efeitos adversos , Idoso , Envelhecimento , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Medicina Preventiva/métodos , Estudos Prospectivos , RiscoRESUMO
OBJECTIVES: An ongoing population-based cohort study was used to assess the prevalence of risk factors, signs of inflammation based on the degree of high sensitive C-reactive protein (hs-CRP) and subclinical atherosclerosis using electron beam computed tomography for detection of coronary artery calcification (CAC). We evaluated the sex related cardiovascular risk stratification based on quantification of subclinical atherosclerosis and inflammation. BACKGROUND: The National Cholesterol Education Program in Adult Treatment Panel III (NCEP ATP III) suggests using CAC and hs-CRP in individuals at intermediate risk. The effect on risk stratification was not yet tested in the general population. METHODS: In the Heinz Nixdorf Recall study 4066 (93.2%) subjects without and 280 (6.8%) of 4345 subjects with coronary artery disease (CAD) (age 45-75 years) were screened in whom data for CAC, hs-CRP, and all risk factors for calculating the Framingham risk score (FRS) were available. This subset of participants was representative of the overall population. Age-adjusted prevalence rate ratios (RR) for prevalence of CAD in relation to risk factors were determined. Framingham risk score groups and NCEP ATP III-based risk categories were calculated. Alterations in risk classification were analyzed using three CAC and hs-CRP categories each: (1) CAC<100, 100-399 and > or =400 or >75th percentile, respectively, (2) hs-CRP< or =1, 1-3, >3mg/L, and (3) a combined CAC and hs-CRP score. RESULTS: Highest RRs of CAD were found for high CAC versus low CAC in men (RR=18.2, 95% CI=10.6-31.3) and for the combined CAC+hs-CRP index in women (RR=11.0, 95% CI=5.1-23.6, both p<0.0001). For high versus low hs-CRP-values a significant RR was found for women only (RR=2.5, 95% CI=1.3-4.6, p<0.01). RRs for other risk factors like hyperlipidemia, HDL, smoking, BMI>30 kg/m(2) were much smaller showing sex differences as well. Thirty percent males and 71% females were classified as low NCEP ATP III risk, 38% and 20% as intermediate and 31% and 9% as high risk. Adding CAC and hs-CRP to NCEP ATP risk categories changed distribution of risk categories considerably with strong differences between sexes. This sex dependence in the magnitude of change in risk categories nearly vanished, when the combined index of CAC and hs-CRP was used. CONCLUSIONS: NCEP ATP III risk categories are significantly and sex-dependently altered using CAC and hs-CRP. CAC is suggested to be of highest value in men; hs-CRP seems to be of complementary value only in women. Measuring atherosclerotic inflammation may improve sex-related risk prediction in a general population.
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Proteína C-Reativa/análise , Calcinose/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Idoso , Aterosclerose/sangue , Calcinose/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Tomógrafos ComputadorizadosRESUMO
INTRODUCTION: Modern investigation modalities allow markers of atherosclerosis to be detected at a subclinical stage. The aim of the study was to analyze the prevalence of these markers in relation to traditional risk factors. METHODS: The population based study included 4814 participants, aged 45 to 75 years, with a response rate of 55.8% of those contacted. The patients' history, psychosocial and environmental risk factors were assessed. RESULTS: The prevalence of obesity was 26.2% in men and 28.1% in women, 26% of men and 21% of women were smokers. Hypertension was found in 46% of men and 31% of women, diabetes in 9.3% of men and 6.3% of women. Markers of subclinical peripheral arterial disease were found in 6.4% of men and 5.1% of women, of subclinical carotid artery disease in 43.2% and 30.7%, and of subclinical coronary artery calcification in 82.3% and 55.2%, respectively. The prevalence of coronary calcification measured using an Agatston Score >100 was in 40% in men and 15% in women, using a score >400, 16.8% and 4.5%, respectively. DISCUSSION: A high prevalence of subclinical atherosclerosis was found in the older population. The follow-up period will demonstrate whether the detection of markers of subclinical atherosclerosis will improve risk stratification beyond that offered by traditional risk factors.
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OBJECTIVE: Inflammatory response seems to be one of the relevant pathophysiological aspects for developing vasospasm in subarachnoid hemorrhage. The probable diagnostic value of intrathecal proinflammatory markers is still unclear and is assessed in this study. METHODS: We analyzed daily clinical data and laboratory tests of the cerebrospinal fluid (CSF) of 64 patients with mostly poor-grade subarachnoid hemorrhage during a period of 14 days. Special attention was given to the relationship between the development of vasospasm and the time course of the intrathecal interleukin (IL)-6 concentrations in CSF (IL-6CSF). The potential power of IL-6CSF for predicting vasospasm was studied. RESULTS: Vasospasm developed in 28.1% of the patients, with a mean onset of 6.4 days after bleeding, and was detected by conventional methods. Patients with vasospasm demonstrated statistically significant higher median values of IL-6CSF on Days 4 and 5 (P < 0.05). Most importantly, the increase of IL-6CSF preceded the conventional signs of vasospasm. A cut-off value of IL-6CSF of at least 2000 pg/ml on Day 4 yielded an 11.72-fold higher relative risk (95% confidence interval, 2.93-46.60) of developing vasospasm, predicting vasospasm with a sensitivity of 88.9% and a specificity of 78.3%. We found a statistically significant correlation between IL-6CSF and delayed cerebral ischemia for Day 7 (P = 0.03). However, there was no correlation with IL-6CSF on any other day and outcome. CONCLUSION: IL-6CSF seems to be a reliable early marker for predicting vasospasm after subarachnoid hemorrhage on Days 4 and 5 before clinical onset.