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1.
Scand J Immunol ; 87(2): 88-98, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29193197

RESUMO

Intracellular signalling in blood leucocytes shows multiple aberrations in acute pancreatitis (AP) complicated by organ dysfunction (OD). We studied whether the aberrations associate with severity of AP and occur in sepsis complicated by OD. The study comprises 14 sepsis patients (11 with shock), 18 AP patients (nine mild; six moderately severe; three severe) and 28 healthy volunteers. Within 48 h after admission to hospital, phosphorylation of nuclear factor-ĸB (NF-ĸB), signal transducers and activators of transcription (STATs) 1,3, and extracellular signal-regulated kinases 1/2 were measured from stimulated or non-stimulated leucocytes using phosphospecific whole blood flow cytometry. In sepsis, as compared with healthy subjects, phosphorylated NF-ĸB levels of monocytes promoted by bacterial lipopolysaccharides, tumour necrosis factor or Escherichia coli cells were lower (P < 0.001 for all), pSTAT1 levels of monocytes promoted by IL-6 were lower (P < 0.05 for all), and STAT3 was constitutively phosphorylated in monocytes, neutrophils and lymphocytes (P < 0.001 for all). In AP, severity was associated with proportions of pSTAT1-positive monocytes and lymphocytes promoted by IL-6 (P < 0.01 for both), constitutive STAT3 phosphorylation in neutrophils (P < 0.05), but not with any of the pNF-ĸB levels. Monocyte pSTAT3 fluorescence intensity, promoted by IL-6, was lower in sepsis and AP patients with OD than in AP patients without OD (P < 0.001). Collectively, signalling aberrations in sepsis with OD mimic those described previously in AP with OD. Possibility that aberrations in STAT1 and STAT3 pathways provide novel markers predicting evolution of OD warrants studies including patients presenting without OD but developing it during follow-up.


Assuntos
Infecções por Escherichia coli/imunologia , Escherichia coli/imunologia , Leucócitos Mononucleares/imunologia , Pancreatite Necrosante Aguda/imunologia , Sepse/imunologia , Adulto , Idoso , Biomarcadores/metabolismo , Células Cultivadas , Progressão da Doença , Feminino , Humanos , Lipopolissacarídeos/imunologia , Masculino , Pessoa de Meia-Idade , Escores de Disfunção Orgânica , Pancreatite Necrosante Aguda/diagnóstico , Prognóstico , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Sepse/diagnóstico , Transdução de Sinais/imunologia
2.
Br J Anaesth ; 114(3): 460-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25472925

RESUMO

BACKGROUND: Interleukin-18 (IL-18) is a pro-inflammatory protein, which mediates ischaemic tubular injury, and has been suggested to be a sensitive and specific biomarker for acute kidney injury (AKI). The predictive value of IL-18 in the diagnosis, evolution, and outcome of AKI in critically ill patients is still unclear. METHODS: We measured urine IL-18 from critically ill patients at intensive care unit (ICU) admission and 24 h. We evaluated the association of IL-18 with developing new AKI, renal replacement therapy (RRT), and 90-day mortality. We calculated areas under receiver operating characteristics curves (AUCs), best cut-off values, and positive likelihood ratios (LR+) for IL-18 concerning these endpoints. Additionally, we compared the predictive value of IL-18 at ICU admission to that of urine neutrophil gelatinase-associated lipocalin (NGAL). RESULTS: In this study population of 1439 patients the highest urine IL-18 during the first 24 h in the ICU associated with the development of AKI with an AUC [95% confidence interval (CI)] of 0.586 (0.546-0.627) and with the development of Stage 3 AKI with an AUC (95% CI) of 0.667 (0.591-0.774). IL-18 predicted the initiation of RRT with an AUC (95% CI) of 0.655 (0.572-0.739), and 90-day mortality with an AUC (95% CI) of 0.536 (0.497-0.574). CONCLUSIONS: IL-18 had poor-to-moderate ability to predict AKI, RRT, or 90-day mortality in this large cohort of critically ill patients. Thus, it should be used with caution for diagnostic or predictive purposes in the critically ill.


Assuntos
Injúria Renal Aguda/urina , Interleucina-18/urina , Avaliação de Resultados da Assistência ao Paciente , Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Idoso , Área Sob a Curva , Biomarcadores/urina , Estado Terminal , Feminino , Seguimentos , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Terapia de Substituição Renal/estatística & dados numéricos
3.
Int J Antimicrob Agents ; 43(5): 423-30, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24630304

RESUMO

The aims of this study were to describe the variability in protein binding of teicoplanin in critically ill patients as well as the number of patients achieving therapeutic target concentrations. This report is part of the multinational pharmacokinetic DALI Study. Patients were sampled on a single day, with blood samples taken both at the midpoint and the end of the dosing interval. Total and unbound teicoplanin concentrations were assayed using validated chromatographic methods. The lower therapeutic range of teicoplanin was defined as total trough concentrations from 10 to 20 mg/L and the higher range as 10-30 mg/L. Thirteen critically ill patients were available for analysis. The following are the median (interquartile range) total and free concentrations (mg/L): midpoint, total 13.6 (11.2-26.0) and free 1.5 (0.7-2.5); trough, total 11.9 (10.2-22.7) and free 1.8 (0.6-2.6). The percentage free teicoplanin for the mid-dose and trough time points was 6.9% (4.5-15.6%) and 8.2% (5.5-16.4%), respectively. The correlation between total and free antibiotic concentrations was moderate for both the midpoint (ρ = 0.79, P = 0.0021) and trough (ρ = 0.63, P = 0.027). Only 42% and 58% of patients were in the lower and higher therapeutic ranges, respectively. In conclusion, use of standard dosing for teicoplanin leads to inappropriate concentrations in a high proportion of critically ill patients. Variability in teicoplanin protein binding is very high, placing significant doubt on the validity of total concentrations for therapeutic drug monitoring in critically ill patients.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Monitoramento de Medicamentos , Teicoplanina/administração & dosagem , Teicoplanina/farmacocinética , Adulto , Idoso , Antibacterianos/metabolismo , Cromatografia , Estado Terminal , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Plasma/química , Ligação Proteica , Teicoplanina/metabolismo , Adulto Jovem
4.
Acta Anaesthesiol Scand ; 57(7): 863-72, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23713703

RESUMO

BACKGROUND: Severe sepsis is one of the leading causes of acute kidney injury (AKI). Patients with sepsis-associated AKI demonstrate high-hospital mortality. We evaluated the incidence of severe sepsis-associated AKI and its association with outcome in intensive care units (ICUs) in Finland. METHODS: This was a predetermined sub-study of the prospective, observational, multicentre FINNAKI study conducted in 17 ICUs during 1 September 2011 and 1 February 2012. All emergency ICU admissions and elective admissions exceeding 24 hours in the ICU were screened for presence of severe sepsis and AKI up to 5 days in ICU. AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria and severe sepsis according to the American College of Chest Physicians/Society of Critical Care Medicine (ACCP/SCCM) criteria. RESULTS: Of the 2901 included patients, severe sepsis was diagnosed in 918 (31.6%, 95% confidence interval [CI] 29.9-33.4%) patients. Of these 918 patients, 488 (53.2% [95% CI 49.9-56.5%]) had AKI. The 90-day mortality rate was 38.1% (95% CI 33.7-42.5%) for severe sepsis patients with AKI and 24.7% (95% CI 20.5-28.8%) for those without AKI. After adjusting for covariates, KDIGO stage 3 AKI was associated with an increased risk for 90-day mortality with an adjusted odds ratio (OR) of 1.94 (95% CI 1.28-2.94), but stages 1 and 2 were not. CONCLUSIONS: More than half of the patients with severe sepsis had AKI according to the KDIGO classification, and AKI stage 3 was independently associated with 90-day mortality.


Assuntos
Injúria Renal Aguda/epidemiologia , Unidades de Terapia Intensiva/estatística & dados numéricos , Sepse/epidemiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Idoso , Coloides/uso terapêutico , Comorbidade , Creatinina/sangue , Feminino , Finlândia/epidemiologia , Mortalidade Hospitalar , Humanos , Incidência , Tempo de Internação/estatística & dados numéricos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/epidemiologia , Estudos Prospectivos , Terapia de Substituição Renal/estatística & dados numéricos , Sepse/complicações , Sepse/microbiologia , Resultado do Tratamento
5.
Clin Microbiol Infect ; 19(12): 1122-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23402373

RESUMO

Heparin-binding protein (HBP) is an inducer of vascular endothelial leakage in severe infections. Fluid accumulation into alveoli is a general finding in acute respiratory distress syndrome (ARDS). Severe acute respiratory failure with ARDS is a complication of influenza A(H1N1) infection. Accordingly, we studied the HBP levels in critically ill patients with infection of influenza A(H1N1).Critically ill patients in four intensive care units (ICUs) with polymerase chain reaction (PCR) confirmed infection of influenza A(H1N1) were prospectively evaluated. We collected clinical data and blood samples at ICU admission and on day 2. Twenty-nine patients participated in the study. Compared with normal plasma levels, the HBP concentrations were highly elevated at baseline and at day 2: 98 ng/mL (62-183 ng/mL) and 93 ng/mL (62-271 ng/mL) (p 0.876), respectively. HBP concentrations were correlated with the lowest ratio of partial pressure of oxygen in arterial blood to fraction of inspired oxygen (PF ratio) during the ICU stay (rho = -0.321, p <0.05). In patients with and without invasive mechanical ventilation, the baseline HBP levels were 152 ng/mL (72-237 ng/mL) and 83 ng/mL (58-108 ng/mL) (p 0.088), respectively. The respective values at day 2 were 223 ng/mL (89-415 ng/mL) and 81 ng/mL (55-97 ng/mL) (p <0.05). The patients with septic shock/severe sepsis (compared with those without) did not have statistically significant differences in HBP concentrations at baseline or day 2. HBP concentrations are markedly elevated in all critically ill patients with influenza A(H1N1) infection. The increase in HBP concentrations seems to be associated with more pronounced respiratory dysfunction.


Assuntos
Peptídeos Catiônicos Antimicrobianos/sangue , Proteínas de Transporte/sangue , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/sangue , Influenza Humana/complicações , Síndrome do Desconforto Respiratório/sangue , Insuficiência Respiratória/sangue , Adulto , Antivirais/uso terapêutico , Proteínas Sanguíneas , Estado Terminal , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Oseltamivir/uso terapêutico , Reação em Cadeia da Polimerase , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/virologia , Insuficiência Respiratória/complicações , Insuficiência Respiratória/virologia , Choque Séptico/sangue
6.
Acta Anaesthesiol Scand ; 57(4): 431-42, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23298252

RESUMO

BACKGROUND: Administration of inotropes in septic patients with low cardiac output or low central/mixed venous saturation is recommended in current guidelines. However, the impact of inotrope use on the outcome of these patients is controversial. We aimed to analyse the association of inotrope treatment with 90-day mortality. METHODS: Data from 420 consecutive patients with septic shock were retrospectively collected from the intensive care unit (ICU) data management system. Factors associated with inotrope treatment were assessed. The association of 90-day mortality with inotrope treatment was first analysed using logistic regression analysis, and second including propensity score based on observed variables for selection to inotrope treatment. A subgroup analysis was performed for the 252 patients with pulmonary artery catheter. RESULTS: One hundred eighty-six (44.3%) patients received inotrope treatment during the first 24 h in ICU. Of those, 168 (90.3%) received dobutamine, 29 (15.6%) levosimendan, and 23 (12.4%) epinephrine. Blood lactate (P < 0.001), central venous pressure, (P < 0.001), and norepinephrine dose (P = 0.03) were independently associated with inotrope treatment. Patients with inotrope treatment had a higher 90-day mortality (42.5% vs. 23.9%, P < 0.001). Age (P < 0.001), Acute Physiology and Chronic Health Evaluation II score (P < 0.001), and inotrope treatment (P = 0.003) were independently associated with 90-day mortality also after adjustment with propensity score. CONCLUSION: The use of inotrope treatment in septic shock was associated with increased 90-day mortality without and after adjustment with propensity to receive inotrope. To differentiate between non-observed biases of severity of septic shock and an unfavourable effect of inotropes, prospective studies are needed.


Assuntos
Cardiotônicos/uso terapêutico , Choque Séptico/tratamento farmacológico , Choque Séptico/mortalidade , Adulto , Idoso , Cateterismo de Swan-Ganz , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Séptico/fisiopatologia , Volume Sistólico
7.
Acta Anaesthesiol Scand ; 56(9): 1175-82, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22845741

RESUMO

BACKGROUND: We aimed to reveal whether the size of an intensive care unit (ICU) or its annual case volume of patients treated with renal replacement therapy (RRT) for acute kidney injury (AKI) is associated with hospital mortality. METHODS: This was a retrospective cohort study in the Finnish Intensive Care Consortium (FICC) database in 2007-2008. We divided the 23 FICC-member ICUs first into small or large according to ICU size, and second into low, medium, or high-volume tertiles according to annual case volume of patients with RRT. We compared crude hospital mortality, Simplified Acute Physiology Score (SAPS) II-, and case-mix-adjusted hospital mortality in small vs. large ICUs and in low- or medium-volume vs. high-volume ICUs. RESULTS: The median (interquartile range) annual case volume of patients with RRT for AKI per one ICU was 25 (19-45). Patients in small or low-volume ICUs were older and less severely ill. Crude and SAPS II -adjusted hospital mortality rates were significantly higher in small ICUs but not significantly different in case volume tertiles. After adjusting for age, severity of illness, intensity of care, propensity to receive RRT, and day of RRT initiation, treatment in low or medium volume ICUs was associated with an increased risk for hospital mortality. CONCLUSIONS: Crude and adjusted hospital mortality rates of patients treated with RRT for AKI were higher in small ICUs. Patients treated in high-volume ICUs had a decreased adjusted risk for hospital mortality compared to those in low-or medium volume ICUs.


Assuntos
Injúria Renal Aguda/mortalidade , Injúria Renal Aguda/terapia , Unidades de Terapia Intensiva/organização & administração , Terapia de Substituição Renal/mortalidade , Terapia de Substituição Renal/estatística & dados numéricos , APACHE , Idoso , Estado Terminal/mortalidade , Estado Terminal/terapia , Feminino , Finlândia/epidemiologia , Tamanho das Instituições de Saúde , Mortalidade Hospitalar , Hospitais Universitários , Humanos , Unidades de Terapia Intensiva/classificação , Unidades de Terapia Intensiva/estatística & dados numéricos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco Ajustado , Resultado do Tratamento
8.
Acta Anaesthesiol Scand ; 56(2): 147-57, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22092254

RESUMO

Continuous renal replacement therapy (CRRT) is the preferred renal replacement therapy modality in the critically ill. We aimed to reveal the literature on the pharmacokinetic studies in critically ill patients receiving CRRT with special reference to quality assessment of these studies and the CRRT dose. We conducted a systematic review by searching the MEDLINE, EMBASE, and the Cochrane databases to December 2009 and bibliographies of relevant review articles. We included original studies reporting from critically ill adult subjects receiving CRRT because of acute kidney injury with a special emphasis on drug pharmacokinetics. We used the minimum reporting criteria for CRRT studies by Acute Dialysis Quality Initiative (ADQI) and, second, the Downs and Black checklist to assess the quality of the studies. We calculated the CRRT dose per study. We included pharmacokinetic parameters, residual renal function, and recommendations on drug dosing. Of 182 publications, 95 were considered relevant and 49 met the inclusion criteria. The median [interquartile range (IQR)] number of reported criteria by ADQI was 7.0 (5.0-8.0) of 12. The median (IQR) Downs and Black quality score was 15 (14-16) of 32. None of the publications reported CRRT dose directly. The median (IQR) weighted CRRT dose was 23.7 (18.8-27.9) ml/kg/h. More attention should be paid both to standardizing the CRRT dose and reporting of the CRRT parameters in pharmacokinetic studies. The general quality of the studies during CRRT in the critically ill was only moderate and would be greatly improved by reports in concordant with the ADQI recommendations.


Assuntos
Pesquisa Biomédica/normas , Estado Terminal , Preparações Farmacêuticas/metabolismo , Farmacocinética , Terapia de Substituição Renal , Injúria Renal Aguda/terapia , Cuidados Críticos , Interpretação Estatística de Dados , Hemofiltração , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Diálise Renal
9.
Acta Anaesthesiol Scand ; 53(1): 61-5, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18945247

RESUMO

BACKGROUND: Tight glycemic control reduces mortality in surgical intensive care patients and in long-term medical intensive care patients. A large study on intensive insulin therapy was prematurely discontinued due to safety issues. As the safety of intensive insulin therapy has been questioned, we screened all patients during a 17-month period to reveal the incidence of hypoglycemia and its effects on the outcome of the patients. METHODS: All patients treated between February 2005 and June 2006 in two intensive care units (ICUs) of a tertiary care teaching hospital were included in the study. A nurse-driven intensive insulin therapy with a target blood glucose level of 4-6 mmol/l had been introduced earlier. The patients were divided into two groups according to the presence of severe hypoglycemia (

Assuntos
Hipoglicemia/tratamento farmacológico , Hipoglicemia/patologia , Insulina/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Feminino , Humanos , Hipoglicemia/sangue , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade
10.
Clin Pharmacol Ther ; 64(4): 363-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9797792

RESUMO

BACKGROUND: Methylprednisolone is a widely used glucocorticoid. In this study, a possible interaction of itraconazole, a potent inhibitor of CYP3A4, with orally administered methylprednisolone was examined. METHODS: In this double-blind, randomized, 2-phase crossover study, 10 healthy volunteers received either 200 mg itraconazole or placebo orally once a day for 4 days. On day 4, each subject ingested a dose of 16 mg methylprednisolone. Plasma concentrations of methylprednisolone, cortisol, itraconazole, and hydroxyitraconazole were determined by HPLC up to 24 hours. RESULTS: Itraconazole increased the total area under the plasma methylprednisolone concentration-time curve 3.9-fold compared with placebo (1968 +/- 470 ng.hr/mL versus 520 +/- 125 ng.hr/mL [mean +/- SD]; P < .001). The peak plasma concentration of methylprednisolone was increased 1.9-fold (221 +/- 49 ng/mL versus 118 +/- 25 ng/mL; P < .001), and its elimination half-life was increased 2.4-fold (4.4 +/- 0.7 hours versus 1.9 +/- 0.3 hours; P < .001) by itraconazole. The mean plasma cortisol concentration during the itraconazole phase, measured 24 hours after ingestion of methylprednisolone, was only about 13% of that during the placebo phase (18 +/- 23 ng/mL versus 139 +/- 60 ng/mL; P < .001). CONCLUSIONS: Itraconazole considerably increases plasma concentrations and effects of oral methylprednisolone, probably by inhibiting its CYP3A4-mediated metabolism. Care should be taken if itraconazole or other potent inhibitors of CYP3A4 are used concomitantly with oral methylprednisolone, particularly during long-term use.


Assuntos
Antifúngicos/farmacologia , Glucocorticoides/sangue , Glucocorticoides/farmacologia , Itraconazol/farmacologia , Metilprednisolona/sangue , Metilprednisolona/farmacologia , Administração Oral , Adulto , Anti-Inflamatórios/sangue , Anti-Inflamatórios/farmacologia , Antifúngicos/administração & dosagem , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Método Duplo-Cego , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacocinética , Meia-Vida , Humanos , Itraconazol/administração & dosagem , Masculino , Metilprednisolona/administração & dosagem , Metilprednisolona/farmacocinética , Oxigenases de Função Mista/antagonistas & inibidores , Valores de Referência
11.
Eur J Clin Pharmacol ; 53(6): 445-9, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9551703

RESUMO

OBJECTIVE: Losartan is metabolised to its active metabolite E-3174 by CYP2C9 and CYP3A4 in vitro. Itraconazole is an inhibitor of CYP3A4, whereas fluconazole affects CYP2C9 more than CYP3A4. We wanted to study the possible interaction of these antimycotics with losartan in healthy volunteers. METHODS: A randomised, double-blind, three-phase crossover study design was used. Eleven healthy volunteers ingested orally, once a day for 4 days, either itraconazole 200 mg, fluconazole (400 mg on day 1 and 200 mg on days 2-4) or placebo (control). On day 4, a single 50-mg oral dose of losartan was ingested. Plasma concentrations of losartan, E-3174, itraconazole, hydroxy-itraconazole and fluconazole were determined over 24 h. The blood pressure and heart rate were also recorded over 24 h. RESULTS: The mean peak plasma concentration (Cmax) and area under the curve [AUC(0-infinity)] of E-3174 were significantly decreased by fluconazole to 30% and to 47% of their control values, respectively, and the t1/2 was increased to 167%. Fluconazole caused only a nonsignificant increase (23-41%) in the AUC and t1/2 of the unchanged losartan. Itraconazole had no significant effect on the pharmacokinetic variables of losartan or E-3174. The ratio AUC(0-infinity)(E-3174)/AUC(0-infinity)losartan was 60% smaller during the fluconazole than during the placebo and itraconazole phases. No clinically significant changes in the effects of losartan on blood pressure and heart rate were observed between fluconazole, itraconazole and placebo phases. CONCLUSION: Fluconazole but not itraconazole interacts with losartan by inhibiting its metabolism to the active metabolite E-3174. This implicates that, in man, CYP2C9 is a major enzyme for the formation of E-3174 from losartan. The clinical significance of the fluconazole losartan interaction is unclear, but the possibility of a decreased therapeutic effect of losartan should be kept in mind.


Assuntos
Antifúngicos/farmacologia , Anti-Hipertensivos/farmacocinética , Hidrocarboneto de Aril Hidroxilases , Fluconazol/farmacologia , Imidazóis/farmacocinética , Itraconazol/farmacologia , Losartan/farmacocinética , Esteroide 16-alfa-Hidroxilase , Tetrazóis/farmacocinética , Adulto , Antifúngicos/sangue , Anti-Hipertensivos/sangue , Estudos Cross-Over , Citocromo P-450 CYP2C9 , Citocromo P-450 CYP3A , Inibidores das Enzimas do Citocromo P-450 , Método Duplo-Cego , Interações Medicamentosas , Feminino , Fluconazol/sangue , Humanos , Imidazóis/sangue , Itraconazol/sangue , Losartan/sangue , Masculino , Oxigenases de Função Mista/antagonistas & inibidores , Valores de Referência , Esteroide Hidroxilases/antagonistas & inibidores , Tetrazóis/sangue
12.
Clin Pharmacol Ther ; 62(5): 510-7, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9390107

RESUMO

BACKGROUND: Quinidine is eliminated mainly by CYP3A4-mediated metabolism. Itraconazole interacts with some but not all of the substrates of CYP3A4; it is therefore important to study the possible interaction of itraconazole with quinidine. METHODS: A double-blind, randomized, two-phase crossover study design was used with nine healthy volunteers. Itraconazole (200 mg) or placebo was ingested once a day for 4 days. A single 100 mg oral dose of quinidine sulfate was ingested on day 4. Plasma concentrations of quinidine, itraconazole, and hydroxyitraconazole, as well as cumulative excretion of quinidine into urine, were determined up to 24 hours. The ECG, heart rate, and blood pressure were also recorded up to 24 hours. RESULTS: On average the peak plasma concentration of quinidine increased to 1.6-fold (p < 0.05), and the area under the concentration-time curve of quinidine increased to 2.4-fold (p < 0.01) by itraconazole. The elimination half-life of quinidine was prolonged 1.6-fold (p < 0.001), and the area under the 3-hydroxyquinidine/quinidine ratio-time curve decreased to one-fifth (p < 0.001) by itraconazole. The renal clearance of quinidine decreased 50% (p < 0.001) by itraconazole, whereas the creatinine clearance was unaffected. The QTc interval correlated with the concentrations of quinidine during both itraconazole and placebo phases (r2 = 0.71 and r2 = 0.79, respectively; p < 0.01), although only minor changes between the phases were observed in other pharmacodynamic variables. CONCLUSIONS: Itraconazole increases plasma concentrations of oral quinidine, probably by inhibiting the CYP3A4 isozyme during the first-pass and elimination phases of quinidine. The decreased renal clearance of quinidine might be the result of the inhibition of P-glycoprotein-mediated tubular secretion of quinidine by itraconazole. The concentrations of quinidine should be closely monitored if itraconazole or some other potent CYP3A inhibitors are used with quinidine.


Assuntos
Antiarrítmicos/sangue , Antifúngicos/farmacologia , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Itraconazol/farmacologia , Oxigenases de Função Mista/efeitos dos fármacos , Quinidina/sangue , Administração Oral , Adulto , Antiarrítmicos/administração & dosagem , Antiarrítmicos/farmacocinética , Área Sob a Curva , Estudos Cross-Over , Citocromo P-450 CYP3A , Método Duplo-Cego , Interações Medicamentosas , Feminino , Meia-Vida , Humanos , Masculino , Quinidina/administração & dosagem , Quinidina/farmacocinética , Valores de Referência , Fatores de Tempo
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