iPAPP: study protocol for a multicentre randomised controlled trial comparing safety and efficacy of intravenous paracetamol and indomethacin for the treatment of patent ductus arteriosus in preterm infants.

INTRODUCTION: Patent ductus arteriosus (PDA) causes severe morbidity in premature infants. Although the use of indomethacin is the standard therapy for PDA, it is sometimes not applicable because of its adverse effects, such as renal and platelet dysfunctions. Paracetamol has emerged as an alternative to indomethacin owing to its excellent safety profile in infants. Of the recently reported case series and clinical trials on the use of paracetamol for PDA, there are few reports in Japan on paracetamol use in preterm infants. Furthermore, indications for the use of paracetamol for PDA have not been approved for use in PDA. While the safety of intravenous paracetamol therapy in case series of preterm infants treated for haemodynamically significant PDA (hsPDA) has been reported, studies which were conducted to compare paracetamol to indomethacin are limited. We, therefore, intend to investigate the hypothesis that intravenous administration of paracetamol has superior safety over indomethacin. METHODS AND ANALYSIS: Multicentre open-label randomised controlled trial for intravenous administration of paracetamol for PDA in preterm infants. The inclusion criteria are (1) hsPDA, (2) gestational age from 24 to 34 weeks and birth weight (BW) from 500 to 2000 g, (3) enrolment between 24 hours and 7 days from birth and (4) obtaining parental consent. The primary outcome is renal dysfunction within 48 hours from the last dose of the study drug. Enrolled patients fulfilling all the inclusion criteria are randomly allocated to either intravenous paracetamol or intravenous indomethacin. This trial requires 110 patients. ETHICS AND DISSEMINATION: The clinical trial would follow Japan's Clinical Trials Act. The trial protocol was approved by the Clinical Research Review Board of Saitama Medical University (approval number: 222001). A written informed consent would be obtained from one of the parents. The results are expected to be published in a scientific journal. TRIAL REGISTRATION NUMBER: jRCTs031220386. PROTOCOL VERSION: 31 March 2022, version 1.0.

Effects of angiotensin II receptor blockers on serum potassium level and hyperkalemia risk: retrospective single-centre analysis.

OBJECTIVE: To examine the effect of angiotensin II receptor blocker (ARB) treatment on serum potassium level and hyperkalaemia risk in a clinical setting with inpatients and outpatients using calcium channel blockers (CCBs) as a reference standard. METHODS: The increased risk of hyperkalaemia associated with ARB treatment is known, however only a few studies have used an active comparator to examine this risk. In this retrospective study at a 320-bed general hospital in Japan, the hospital information system was used to identify patients with at least one prescription for an ARB (819 patients) or a CCB (1015 patients) who were naive to these drugs before study initiation. Serum potassium levels before and after ARB treatment were compared. Additionally, the unadjusted and adjusted hazard ratios for the risk of hyperkalaemia in the ARB and CCB users were estimated. RESULTS: The serum potassium level was higher in patients receiving ARB treatment (0.05 mEq/L, p=0.02) compared with those on CCB treatment. However, there was no significant association between ARB use and hyperkalaemia (adjusted HR 0.91, 95% CI 0.42 to 1.99, p=0.82). CONCLUSION: The increase in serum potassium level after ARB initiation makes it necessary to monitor serum potassium levels continuously during ARB treatment; however, the risk of hyperkalaemia appeared to be similar for ARB and CCB treatments.

Prevalence of therapeutic drug monitoring and adherence to imatinib in chronic myeloid leukemia in Japan.

OBJECTIVE: The effectiveness of imatinib, a tyrosine kinase inhibitor recommended for the treatment of chronic myeloid leukemia, is associated with high adherence and trough plasma imatinib concentrations of ~ 1,000 ng/mL. However, adherence and therapeutic drug monitoring (TDM) for imatinib have hardly been reported. This study evaluated the prevalence of TDM and adherence to imatinib for chronic myeloid leukemia in Japan. MATERIALS AND METHODS: Monthly insurance claims data for ~ 5.6 million individuals aged 20 - 74 years between June 1, 2005 and December 31, 2017 were studied. Patients with at least one prescription for imatinib were included to calculate adherence and the annual mean prevalence of TDM for imatinib. RESULTS: A total of 498 patients with 9,620 prescriptions of imatinib were included. After 2013, the number of imatinib prescriptions and the number of patients treated with imatinib were over 1,000 and 200, respectively. The mean annual prevalence of TDM for imatinib was 12.2% (95% confidence interval (CI), 8.1 - 16.1%). Antihyperuricemic drugs and steroids increased the likelihood of TDM. The medication possession ratio for assessment of adherence was 93.5% (95% CI: 91.8 - 95.5%). The annual mean prevalence of TDM for imatinib was low, although adherence was high. CONCLUSION: To encourage the measurement of plasma concentrations of imatinib in clinical settings, adding a package insert, a summary of product characteristics, and a patient information leaflet regarding the implementation of TDM is justified and warrants further attention.

Furosemide clearance in very preterm neonates early in life: A pilot study using scavenged samples.

BACKGROUND: Furosemide is an off-label drug, frequently used as a diuretic in neonates with oliguria and/or edema. Its clearance in preterm neonates is lower than in term neonates or children. We aimed, herein, to clarify furosemide clearance (CL) in very preterm (VP) neonates (<28 weeks' gestation) within the first 2 weeks of life and identify the factors predictive of the pharmacokinetics (PK) parameters, such as CL. METHODS: Furosemide was administered at 0.5 or 1 mg/kg in a 0.5-h infusion via a syringe pump; blood samples were drawn from an artery or vein after the intravenous injection. The serum furosemide concentration was measured using high-performance liquid chromatography. The PK parameters were then analyzed using Bayesian estimation. RESULTS: Thirteen blood samples were obtained from 10 VP neonates after intravenous injection. The mean postconceptional age and mean postnatal days at exposure to furosemide were 26.9 weeks and 7.1 days, respectively. The estimated mean CL was 16.5 mL/kg/h. The mean distribution volume (Vd) and elimination half-life (t1/2) were 0.37 L/kg and 15.3 h, respectively. Furosemide CL was negatively associated with serum creatinine (SCr) [CL = 84.2 - 67.1 × SCr (mg/dL)]. CONCLUSIONS: Very preterm neonates within the first 2 weeks of life had a higher CL than subjects in other preterm neonatal studies. The SCr level was the sole parameter influencing furosemide CL and might serve as a good index for furosemide dosing in VP neonates.

Comparison between high and low potency statins in the incidence of open-angle glaucoma: A retrospective cohort study in Japanese working-age population.

Some findings on the association between glaucoma and statins in the Asian population have been reported. We conducted a retrospective cohort study using health insurance claims data maintained by the JMDC Inc., which comprises data on about three million individuals representing 2.4% of the Japanese population. The association between the potency of statins and open-angle glaucoma in Japanese working-age population was examined using a commercially available health insurance claims and enrollment database. We identified 117,036 patients with a prescription of statins between January 1, 2005 and March 31, 2014; 59,535 patients were selected as new statin users. Of these, 49,671 (83%) patients without glaucoma who were prescribed statins for the first time were part of the primary analysis. New users of statin were defined as those with a prescription of statin at the beginning of the study, but without a prescription six months earlier. The cohort comprised 29,435 (59%) and 20,236 (41%) patients with a prescription of high-potency statin (atorvastatin and rosuvastatin) and low-potency statin (pravastatin, fluvastatin, pitavastatin, and simvastatin), respectively. Using Cox proportional hazards regression analysis, hazard ratios (HRs) were estimated for glaucoma adjusted for baseline characteristics. Although some baseline characteristics were not similar between the high-potency and low-potency statin groups, the standardized difference for all covariates was less than 0.1. No associations were found between high-potency statin use and glaucoma (adjusted HR = 1.08; 95% confidence interval, 0.93-1.24) in the primary analyses, using the risk for glaucoma in the low-potency statin group as reference. The risk of glaucoma with individual statin use was not significantly different from that with pravastatin. No significant association was found between high-potency statins and the increased risk of glaucoma in Japanese working-age population. Further studies are needed to examine the association between statins and glaucoma in the elderly population.

Frequency of Clinical Monitoring of Serum Concentrations of Digoxin, Potassium, and Creatinine, and Recording of Electrocardiograms in Digoxin-Treated Patients: A Japanese Claims Database Analysis.

Guidelines for cardiovascular drug therapy recommend monitoring serum digoxin concentration (SDC) in patients receiving digoxin treatment, especially those with renal dysfunction and hypokalemia. However, only a few studies have reported the prevalence of SDC monitoring and laboratory testing in clinical practice. Therefore, the aim of this study was to describe the frequency of SDC monitoring and laboratory testing in digoxin users and to assess the association between SDC monitoring and patient characteristics. We used the Japanese insurance claims data covering approximately 1.7 million patients aged 20-74 years between January 1, 2005 and March 31, 2014. All patients who had at least one prescription for digoxin were included. The frequency of SDC and laboratory tests was calculated and the association between patient characteristics and SDC monitoring was assessed using logistic regression analysis. A total of 98867 prescriptions of digoxin were issued to 3458 patients between 2005 and 2014. The annual mean frequencies of monitoring SDC, serum potassium level and serum creatinine level and of recording electrocardiograms was 16.8, 34.8, 38.7, and 24.1%, respectively. Atrial fibrillation, chronic heart failure, renal diseases, and use of oral anticoagulants were associated with SDC monitoring. We found the frequency of SDC monitoring to be relatively low in Japanese clinical practice.

Voriconazole concentration is inversely correlated with corticosteroid usage in immunocompromised patients.

BACKGROUND: Voriconazole (VRCZ) is a broad-spectrum antifungal agent that can be administered both orally and intravenously. A high level of intra- and interindividual variability in serum drug therapeutic concentrations has been reported. We analyzed the influence of corticosteroid use on serum VRCZ concentration by assessing the correlation between corticosteroid dose and VRCZ trough level. METHODS: Immunocompromised patients treated with VRCZ with or without corticosteroid use from June 2010 to March 2017 (6 years and 8 months) were reviewed in our institute. VRCZ and the corticosteroids were administered orally or intravenously. Corticosteroid treatment was considered as "concurrent" only if it was administered within 3 days before or after the initiation of VRCZ. All corticosteroids were converted to a prednisolone-based dosage according to their anti-inflammatory effect (relative glucocorticoid activity). VRCZ concentration was measured at the trough point on the day of steady state. RESULTS: A total of 85 samples were obtained from 38 patients. The medical records of 23 women and 15 men, with a median age of 61 years (range: 35-86), were reviewed. Twenty-one patients (55.3%, 21/38) received chemotherapy, and 28 (73.7%, 28/38) received corticosteroid therapy. The average and median daily doses of corticosteroids were 59.2 and 89.8 mg, respectively (range: 0.714-377). VRCZ concentration was inversely correlated with corticosteroid dose (r = -.26). The VRCZ concentration was significantly decreased in the corticosteroid user compared to nonuser (P = .013). We evaluated the association of VRCZ concentration and corticosteroid dose in 3 patients among our cohorts for whom more than 5 points of data were available. Intraindividual analysis revealed the trough level of VRCZ concentration decreased as the corticosteroid dose increased. The patients' underlying diseases were hematological diseases (n = 25) and immunological diseases (n = 13). Among accrual patients, no patients were undergoing stem cell transplantation, and no patients were treated with known confounders such as calcineurin inhibitors or phenytoin. CONCLUSIONS: VRCZ might be metabolized by an enzyme induced by corticosteroid treatment; therefore, intraindividual variation in VRCZ metabolism should be considered prior to concurrent treatment, especially for patients with hematological malignancies treated with corticosteroids.

Prevalence of Therapeutic Drug Monitoring for Lithium and the Impact of Regulatory Warnings: Analysis Using Japanese Claims Database.

BACKGROUND: Therapeutic drug monitoring (TDM) for lithium is recommended in guidelines; however, the prevalence of TDM for lithium is seldom reported. We have therefore investigated the prevalence of TDM for lithium and evaluated the impact of the regulatory warnings requiring routine TDM for lithium. METHODS: Monthly claims data covering around 1.7 million persons aged 20-74 years old during the period January 1, 2005, and March 31, 2015, were evaluated. All patients who had at least one prescription for lithium were selected and included to calculate the annual prevalence of TDM for lithium. Also we assessed whether the 2 regulatory warnings requiring routine TDM for lithium and issued in April 2012 and September 2012 had an impact on TDM for lithium, using segmented regression analysis. RESULTS: Between 2005 and 2014, 136,956 prescriptions of lithium were issued to 5823 patients, and the annual prevalence of TDM for lithium was 14.9% (95% confidence interval, 14.7%-15.1%). The analysis revealed that the mean prevalence increased abruptly by 6.9% (P = 0.001) after the regulatory warning in April 2012, whereas that the warning in September 2012 decreased by 1.2% (P = 0.47). There was no significant change in trends of period prevalence after the warning in April 2012 (April 2012-August 2012) compared with prevalence before the warning (April 2010-March 2012). Similarly, no significant change was observed in the trends before (April 2012-August 2012) and after (September 2012-March 2014) the subsequent warning in September 2012. CONCLUSIONS: Results showed that the prevalence of TDM for lithium was low, although TDM for lithium was strongly recommended by the guidelines. Regulatory warnings requiring compliance with the measurement of blood levels during treatment with lithium, issued twice during the five-month period, were associated with an increase in the prevalence of TDM for lithium. However, the impact of the second warning was not remarkable compared with the first warning.

Prediction Model of Serum Lithium Concentrations.

INTRODUCTION: Therapeutic drug monitoring is necessary for lithium, but clinical application of several prediction strategies is still limited because of insufficient predictive accuracy. We herein proposed a suitable model, using creatinine clearance (CLcr)-based lithium clearance (Li-CL). METHODS: Patients receiving lithium provided the following information: serum lithium and creatinine concentrations, time of blood draw, dosing regimen, concomitant medications, and demographics. Li-CL was calculated as a daily dose per trough concentration for each subject, and the mean of Li-CL/CLcr was used to estimate Li-CL for another 30 subjects. Serum lithium concentrations at the time of sampling were estimated by 1-compartment model with Li-CL, fixed distribution volume (0.79 L/kg), and absorption rate (1.5/hour) in the 30 subjects. RESULTS: One hundred thirty-one samples from 82 subjects (44 men; mean±standard deviation age: 51.4±16.0 years; body weight: 64.6±13.8 kg; serum creatinine: 0.78±0.20 mg/dL; dose of lithium: 680.2±289.1 mg/day) were used to develop the pharmacokinetic model. The mean±standard deviation (95% confidence interval) of absolute error was 0.13±0.09 (0.10-0.16) mEq/L. DISCUSSION: Serum concentrations of lithium can be predicted from oral dosage with high precision, using our prediction model.

Effect of high-potency statins on HbA1c in patients with or without diabetes mellitus.

BACKGROUND: The increased risk of new-onset diabetes with statin use, including high-potency statins, is well known. However, the effects of high-potency statins on HbA1c are unclear. A retrospective cohort study was conducted to examine the effect of high-potency statins on HbA1c in patients with or without diabetes. The study enrolled new statin users identified via the electronic healthcare database of the general hospital in Japan. METHODS: Following identification of all individuals (n = 4,672) who had been prescribed a lipid lowering drug at least once between January 1, 2010 and July 31, 2014, new statin users were selected (n = 1,136). Patients were excluded if they had been prescribed treatment with a statin within the preceding 6-month period. HbA1c levels before and during high-potency statin treatment were compared using the dependent t-test. In addition, the hazard ratio for the incidence of diabetes with high-potency statin treatment was estimated, using low-potency statins as a reference. RESULTS: In patients with diabetes (n = 153), mean HbA1c (%) levels significantly increased by 0.4 % after high-potency statin use (7.57 ± 1.58; p = 0.0002) compared to baseline (7.18 ± 1.37). Similarly, HbA1c (%) levels significantly increased from 5.78 ± 0.38 to 5.92 ± 0.45 (p < 0.0001) after high-potency statin use in patients without diabetes (n = 165). Furthermore, a trend toward an increase in HbA1c was found for all of the high-potency statins irrespective of a history of diabetes. CONCLUSIONS: The use of high-potency statins may increase HbA1c levels in patients with or without diabetes.

Developing population pharmacokinetic parameters for high-dose methotrexate therapy: implication of correlations among developed parameters for individual parameter estimation using the Bayesian least-squares method.

Bayesian estimation enables the individual pharmacokinetic parameters of the medication administrated to be estimated using only a few blood concentrations. Due to wide inter-individual variability in the pharmacokinetics of methotrexate (MTX), the concentration of MTX needs to be frequently determined during high-dose MTX therapy in order to prevent toxic adverse events. To apply the benefits of Bayesian estimation to cases treated with this therapy, we attempted to develop an estimation method using the Bayesian least-squares method, which is commonly used for therapeutic monitoring in a clinical setting. Because this method hypothesizes independency among population pharmacokinetic parameters, we focused on correlations among population pharmacokinetic parameters used to estimate individual parameters. A two-compartment model adequately described the observed concentration of MTX. The individual pharmacokinetic parameters of MTX were estimated in 57 cases using the maximum likelihood method. Among the available parameters accounting for a 2-compartment model, V1, k10, k12, and k21 were found to be the combination showing the weakest correlations, which indicated that this combination was best suited to the Bayesian least-squares method. Using this combination of population pharmacokinetic parameters, Bayesian estimation provided an accurate estimation of individual parameters. In addition, we demonstrated that the degree of correlation among population pharmacokinetic parameters used in the estimation affected the precision of the estimates. This result highlights the necessity of assessing correlations among the population pharmacokinetic parameters used in the Bayesian least-squares method.

Limited sampling strategy for the estimation of mycophenolic acid area under the concentration-time curve treated in Japanese living-related renal transplant recipients with concomitant extended-release tacrolimus.

Mycophenolate mofetil (MMF) is used for oral administration to prevent rejection in renal transplant recipients, and is rapidly converted into mycophenolic acid (MPA), the active metabolite, by hydrolysis in vivo. The area under the concentration-time curve (AUC(0-12 h)) of MPA is considered to be an effective pharmacokinetics parameter for predicting acute rejection. However, frequent blood sampling is required to calculate AUC(0-12 h), which imposes a burden on patients and providers. Therefore, we examined a limited sampling strategy (LSS) for estimation of MPA-AUC(0-12 h) using only a trough level (C0) and two points including C0 in Japanese living-related renal transplant recipients with concomitant extended-release tacrolimus (ER-TAC). The present study suggests that better estimation of MPA-AUC(0-12 h) can be obtained by using two points including C0 as compared with only C0 regardless of transplant progress. Furthermore, blood collection points showing the highest estimation of MPA-AUC(0-12 h) by adding to C0 were C4 at pre-transplantation (Tx) and 1 month post-Tx, and C6 at 3 months post-Tx. We conjecture that changes in renal function and serum albumin (Alb) accompanying transplant progress are aggravating factors in terms of estimation, because there was also a significant difference in the reciprocal of serum creatinine (1/Scr) and Alb between pre-Tx and post-Tx in this study. In conclusion, the present study provides useful information for effective and efficient monitoring of MPA levels in Japanese living-related renal transplant recipients.

Effects of angiotensin II AT1-receptor blockade on high fat diet-induced vascular oxidative stress and endothelial dysfunction in Dahl salt-sensitive rats.

We examined the effects of angiotensin II AT1-receptor blockade with olmesartan on high fat (HF) diet-induced vascular oxidative stress and endothelial dysfunction in normal salt (NS) diet-fed Dahl salt-sensitive (DSS) rats. Treatment with NS + HF diet (32% crude fat, 0.3% NaCl) for 20 weeks significantly increased blood pressure in DSS rats. NS + HF diet-fed DSS rats also showed higher plasma levels of thiobarbituric acid-reactive substances, aortic superoxide production, and mRNA levels of p22(phox) and gp91(phox) in aortic tissues than NS diet-fed DSS rats. Furthermore, acetylcholine-induced vasorelaxation of aorta from NS + HF diet-fed DSS rats was significantly reduced. In NS + HF diet-fed DSS rats, treatment with olmesartan medoxomil (10 mg/kg per day, p.o.) and hydralazine (25 mg/kg per day, p.o.) similarly decreased blood pressure. However, in these animals, only olmesartan normalized plasma levels of thiobarbituric acid-reactive substances, vascular superoxide in aortic tissues, and acetylcholine-induced vasorelaxation. These data indicate that HF diet-induced hypertension is associated with vascular oxidative stress and endothelial dysfunction in NS diet-treated DSS rats. Inhibition of angiotensin II AT1 receptors may elicit beneficial effects on HF-induced hypertension and vascular injury in subjects that have genetically enhanced sodium-sensitive blood pressure.

Excess fluid distribution affects tacrolimus absorption in peritoneal dialysis patients.

BACKGROUND: Excess fluid distribution is a common disorder in peritoneal dialysis (PD) patients. Tacrolimus malabsorption may also occur in PD patients, and may lead to acute allograft rejection after transplantation. The purpose of this study was to evaluate the relationship between tacrolimus pharmacokinetics and excess fluid distribution according to pre-transplant dialysis modality. METHODS: We retrospectively analyzed 41 adult living-donor kidney transplantations, including nine PD patients and 32 hemodialysis (HD) patients. We examined tacrolimus pharmacokinetics in the peri-operative period and determined the association between the tacrolimus absorption rate and body weight reduction. The absorption efficacy of tacrolimus was evaluated as the dose-normalized tacrolimus absorption rate. Tacrolimus concentrations in PD effluent were measured by high-performance liquid chromatography. RESULTS: The tacrolimus absorption rate on the day before kidney transplantation tended to be lower in PD patients than in HD patients; however, the rate improved after kidney transplantation and was similar in both groups of patients. The peak tacrolimus concentration time was later in PD patients than in HD patients. The body weight reduction after kidney transplantation was greater in PD patients than in HD patients, and was significantly associated with the change in tacrolimus absorption rate (p=0.04, r=0.32). Only 0.002% of the oral tacrolimus dose was removed by PD itself. CONCLUSION: Excess fluid distribution in PD patients appears to contribute to tacrolimus malabsorption rather than PD itself. We should consider the risk of tacrolimus malabsorption in patients with possible excess fluid distribution, particularly in PD patients.

Erythroid recovery affects tacrolimus levels after engraftment during stem cell transplantation.

Tacrolimus is commonly used in stem-cell transplants (SCT) for prophylaxis of graft-versus-host disease and is continuously administered throughout transplantation. The dose of tacrolimus is frequently decreased to maintain a desired concentration during the recovery of hemocytes after engraftment. If parameters which affect tacrolimus clearance are identified, it is of clinical use to estimate concentrations and aid dosing. The objective of this study was to identify which hematologic parameters affect tacrolimus clearance. Seventeen consecutive Japanese patients with hematological malignancies who received allogeneic SCT between March 2004 and January 2007 were enrolled in this study. Their steady-state concentrations were routinely measured and standardized as the concentration/dose (C/D) ratio ((ng/mL)/(mg/kg/d)). Multivariate analysis was performed to identify which hemocyte parameters affected the C/D ratio. Of the 13 patients, gradual dose reduction was required to combat elevated tacrolimus concentrations. The mean post-engraftment C/D ratio was higher than the pre-engraftment C/D ratio in each patient. The mean C/D ratio for all patients after engraftment was 1.56-fold higher (p=0.00004, range: 1.04-3.03) than that before engraftment. The variation ratio was calculated by dividing the C/D ratio by that on the engraftment day. Multivariate analysis revealed that the reticulocyte (RET) level (×10(3) count/µL) was the sole parameter influencing this ratio, and both parameters were expressed as: Variation ratio=0.004×RET+1.0. RET recovery of patients could influence the C/D ratio and tacrolimus clearance was affected by recipient original red blood cells, but not that of transfused red blood cells.

[Case of encephalopathy seemingly caused by tacrolimus at blood concentration near the upper limit of therapeutic range].

We report a case of encephalopathy seemingly caused by tacrolimus (FK506) in spite of blood concentration near the upper limit of therapeutic range. A 26-year-old man received FK506 to prevent acute graft-versus-host disease after hematopoietic stem cell transplantation. He underwent an intravenous injection of FK506 the day before transplantation (day -1). He developed headache, hypertension, nausea and vomiting from day 2 to day 3. A computed tomography scan showed a low density area with unclear border in the bilateral cerebellar hemispheres. Thereafter, these symptoms improved with discontinuation of FK506, which was strongly suggestive of encephalopathy caused by FK506. The blood concentration of FK506 at the onset of encephalopathy was 21.7 ng/mL. Although this value was slightly higher than the standard therapeutic range (10-20 ng/mL), it was within clinically acceptable range in the early stage after stem cell transplantation. This indicates that even if the blood concentration of FK506 is within the therapeutic range, encephalopathy may develop. In summary, although the blood concentration of FK506 is useful as an indicator for prevention of encephalopathy, we propose careful monitoring not only of the blood concentration but also clinical status for the detection of initial symptoms and prevention of aggravation.

Pharmacokinetics of prophylactic micafungin in very-low-birth-weight infants.

We evaluated the use of micafungin as a prophylaxis in very-low-birth-weight infants. Micafungin was first administered to 25 very-low-birth-weight infants 12 to 24 hours after birth at a dose of 1 mg/kg/d. the apparent volume of distribution, the apparent elimination rate constant, the elimination half-life, and the total body clearance (mean +/- SD) were 0.76 +/- 0.28 L/kg, 0.12 +/- 0.041 1/h, 6.7 +/- 2.2 h, and 0.089 +/- 0.047 L/kg/h, respectively.

Dose adjustment of phenytoin for comedication in Japanese patients with epilepsy.

This study sought a suitable physiological parameter related to daily phenytoin (PHT) dose (D) providing a steady-state serum concentration (Ct) and analyzed the influences of coadministered antiepileptic drugs on Ct quantitatively to adjust PHT dose. Data were derived from a total of 368 patients with epilepsy treated with multiple oral administrations of PHT. Phenobarbital, carbamazepine, valproic acid, zonisamide, clonazepam, and ethosuximide were coadministered. For the administration of PHT alone, 4 types of parameter, that is, total body weight, total body water volume, body surface area, and extracellular water volume (VECW) were examined. Then, a Michaelis-Menten kinetic model was postulated including VECW, which was assumed to detect the effect of the coadministered drug quantitatively. Adopting VECW as a transforming factor, the concentration to dose (L:D) ratio [Ct/(D/VECW)] was independent of the patient's age and gender in relation to Ct and expressed as Ct/(D/VECW) = 0.0245 x Ct + 0.076. Analysis clarified that ratios were estimated as 0.90, 0.91, 0.89, and 0.84 for phenobarbital, carbamazepine, valproic acid, and zonisamide, respectively, to maintain the same Ct concentration of PHT. Influences were not detected as the number (> or =2) of coadministered drugs increased, regardless of factor type. PHT clearance changed in an age-dependent manner and was usually poorly correlated with weight-based doses. VECW was more closely correlated with age-dependent changes in physiological parameters such as clearance. VECW was considered to remove the influence of age on clearance, and estimated ratios could be used for all age groups. In the case of the addition or removal of concomitant treatment with antiepileptic drugs in the same patient, the daily PHT dose was calculated using the value of each ratio or its reciprocal. Our results could be helpful in determining PHT dosing.

[Infection treatment caused by multiple-drug-resistant Pseudomonas aeruginosa in a patient undergoing allogeneic hematopoietic stem cell transplantation].

Infections caused by multiple-drug-resistant Pseudomonas aeruginosa (MDRP) are a clinically significant problem. We reported here the effective use of combination therapy in a patient with infection caused by MDRP according to an interventional treatment strategy suggested by a pharmacist. The patient was a 70-year-old male who underwent allogeneic hematopoietic stem cell transplantation. On day 45 after transplant, MDRP was newly isolated from urine, but the diagnosis at that time was colonization. On day 61, the patient developed a fever (> or =38.0 degrees C). In addition, laboratory data showed that C-reactive protein (CRP) was also increased. At the medical team conference, the pharmacist proposed the following treatment strategy for this infection. Aztreonam and amikacin were intravenously administered at doses of 2 g/day and 800 mg/day, respectively. The subsequent clinical course was well controlled, but the infection recurred and was aggravated. Aztreonam and ciprofloxacin were then intravenously administered at doses of 4 g/day and 600 mg/day, respectively, resulting in the alleviation of fever in the patient as well as a decrease in CRP and disappearance of MDRP isolates from urine on day 67; that is, MDRP infection was consequently well controlled. In conclusion, the combination therapy between aztreonam and amikacin, or ciprofloxacin may be clinically useful for severe infections of MDRP in compromised hosts.

[Preventive effects of newquinolones for endogenous infection in patients receiving allogeneic hematopoietic stem cell transplantation--comparison between bone marrow transplantation, peripheral blood stem cell transplantation, and cord blood transplantation].

We performed a retrospective study to examine the preventive effects of newquinolones for endogenous infection in patients receiving various allogeneic hematopoietic stem cell transplantation including bone marrow transplantation (BMT), peripheral blood stem cell transplantation (PBSCT), and cord blood transplantation (CBT). Forty-nine patients were enrolled. Ciprofloxacin or norfloxacin was orally administered for intestinal sterilization from day -14 until engraftment. As a result, the period from transplantation until engraftment was significantly longer in CBT group than in BMT group. The febrile index (the ratio of the febrile (> or =38.0 degrees C) period during neutropenia (< or =500 cells/mm(3)) and C-reactive protein (CRP)-positive index (the ratio of CRP-positive (> or =2.0 mg/dl) period during neutropenia) were comparable among the three groups. In addition, no gram-negative bacteria in stool was isolated in the three groups; that is, an endogenous infection of gram-negative bacteria, a potential pathogen, was well controlled by newquinolones. We should be careful when interpreting the results of this small study; however, newquinolones are clinically effective for endogenous infection of gram-negative bacteria in patients receiving not only BMT, but also PBSCT and CBT.