Comparison of methods of carbamazepine dosage, individualization in epileptic patients

The aim of the present work was to analyse the predictive capacity of different optimization methods for carbamazepine dosage regimens according to population pharmacokinetic parameters and/or serum levels data. Calculations were performed using a multiple non-linear regression program (MULTI 2 BAYES) with two different options: (a) using the ordinary least squares methods and (b) the least squares method based on the Bayesian algorithm. The predictive capacity of the three methods was analysed comparing the serum levels values in patients predicted by each method and those observed later. The performance obtained was poor and even unacceptable when dosage prediction was based on the mean parameters of the population studied (Method A) and when only one data point relating to the serum carbamazepine levels was available (Method B). When two serum levels data were used the standard deviation of the mean prediction error was only clinically acceptable when Bayesian non-linear regression was applied (Method C). When the number of serum levels data points was 3 or 4 the errors were acceptable from a clinical point of view and no significant differences could be found between the use of the simple and Bayesian version at the same level of information.

TDM of theophylline--compliance evaluation

Non-compliance to dosage regimes is an important clinical problem with severe repercussions for the management of chronic illnesses requiring continued treatment. In the present study, we evaluated the degree of non-compliance in a group of 100 patients with chronic asthma undergoing continued treatment with theophylline, and the effect of the application of a monitoring programme on their degree of compliance. The evaluation was carried out by anamnesis and from the level/dose ratio. In the control group studied (n = 50) the degree of non-compliance was 44% and in the previously monitored group (n = 50) it was 18%. Serum theophylline levels in the former were: 7.6 +/- 5.8 micrograms/ml, significantly lower (P less than 0.005) than that observed in the latter: 10.1 +/- 4.0 micrograms/ml. The use of monitoring programmes can improve the degree of compliance.

African swine fever virus DNA: deletions and additions during adaptation to growth in monkey kidney cells

Restriction enzyme cleavage maps for the fragments produced by Cla I, Sal I and Sma I have been constructed for African swine fever virus (ASFV) DNA grown in pig leukocytes (strain E70 L6) and after adaptation to growth in MS monkey kidney cells (strain E70MS14). The mapping data revealed that before adaptation to growth in MS cells, the size of the DNA from ASFV strain E70 L6 was l73 Kbp and after adaptation it was only l56 Kbp. The decrease in size was produced by deletions and additions mainly in the terminal regions of the genome. These genetic variations were located between 0.0 to 0.01 m.u. (Cla I-M1 fragment), 0.04 to 0.14 m.u. (Sma I-B1, Sal I-A1 fragments), 0.51 to 0.52 m.u. (Cla I-O fragment), 0.84 to 0.86 m.u. (Sma I-H1), 0.95 to 0.97 m.u. (Cla I-A1, Cla I-G1 fragments) and 0.99 to 1.0 m.u. (Cla I-G1) on viral genome of ASFV grown in pig leukocytes.

Pleural fluid levels of cefoxitin in patients with renal impairment

The pharmacokinetics of cefoxitin was studied in 14 patients with a pleural effusion, 8 of which had normal renal function and the other 6 varying degrees of renal impairment. All patients received a single dose of 30 mg/kg i.v. bolus of the antibiotic. The serum and pleural fluid concentrations of cefoxitin were determined microbiologically. The serum elimination half-life of the antibiotic in the group of patients with normal renal function had a mean value of 1.35 +/- 0.56 h while that of the second group ranged between 2.00 h and 40.79 h, according to the deterioration in renal function. The disappearance half-life of cefoxitin from pleural fluid increased parallel to the degree of renal impairment, reaching a value of 30.09 h for a creatinine clearance (Ccr) of 5.8 ml/min. From the data obtained, dosage regimens were programmed according to the degree of renal function with the aim of achieving safe and efficient cefoxitin levels in both biological fluids.

Separation of Mycobacterium gadium from other rapidly growing mycobacteria on the basis of DNA homology and restriction endonuclease analysis

DNA was isolated from Mycobacterium gadium with high purity. Its G + C content was between 64 and 67 mol%. The homology of M. gadium DNA with DNA from three other rapidly growing mycobacteria was less than 22%, which indicates that M. gadium is a discrete genomic species. Analysis of the DNAs with restriction endonucleases supported this finding.

Maple syrup urine disease variant form: presentation with psychomotor retardation and CT scan abnormalities

A female infant with an intermediate variant of maple syrup urine disease is described. The patient had psychomotor retardation and high plasma levels of branched chain aminoacids. Leucine decarboxylation rate in leukocytes was diminished. Cranial computed tomography showed decreased density in the cerebral white matter. After starting dietary treatment the infant resumed her psychomotor development and the abnormal images previously seen on computed tomography disappeared.

Survival of myocutaneous flaps. Experimental evaluation by intra-arterial injection of a dye

Ninety-four myocutaneous island flaps of the pectoralis major were studied in the rabbit using sulfan blue (Disulphine-blue). In 13 cases, the dye was injected intra-arterially in the acromiothoracic artery before the flap was lifted, and 47 more were injected after the lifting of the flap. In 34 further cases, sulfan blue was injected intravenously once the flap had been lifted. In another 16 flaps, vascularization was studied by means of "diaphanization" (ie, making the tissue transparent or diaphenous in nature). In all groups, the surviving length of flap was observed to be greater than the stained length. Intra-arterial administration of sulfan blue was associated with reduced flap survival. Viable flap length was not related to the anatomy of the vascular base.

Pharmacokinetics of cefoxitin in patients with pleural effusion on a multiple dosage regimen

The pharmacokinetics of cefoxitin were studied in 6 healthy volunteers and in 5 patients with pleural effusion of varied etiologies. The antibiotic was administered in a multiple dosage regimen of 30 mg/kg every 8 hours. Cefoxitin concentrations in serum and pleural fluid were determined after administration of the third dose corresponding to the levels of steady-state in both fluids. The elimination half-life of the antibiotic from the pleural fluid comes to 3.51 +/- 1.15 h, which is significantly greater than the serum half-life, (t 1/2 = 1.42 +/- 0.51 h). This kind of multiple dosage regimen ensures therapeutic levels of cefoxitin in the pleural fluid during the entire treatment.

A new patient with dicarboxylic aciduria suggestive of medium-chain Acyl-CoA dehydrogenase deficiency presenting as Reye's syndrome

A new patient with medium-chain dicarboxylic aciduria and suberyl glycinuria during an attack of acute illness is reported. When, inadvertently he was given medium-chain triglycerides for 2 days, the excretion of abnormal metabolites of medium-chain fatty acids increased and hepatomegaly became more pronounced. During remission a low excretion of the metabolites were observed. After 16 h of fasting hypoglycaemia was accompanied by an increase of urinary dicarboxylic acids and psi-hydroxyacids similar to that found on admission. Interestingly this urinary organic acid pattern persisted 8 h after intravenous administration of glucose. In a blood sample obtained after 16 h of fasting there was hypoketonaemia and increased levels of total free fatty acids, octanoic, decanoic and cis-4-decenoic acids. These biochemical data suggest the existence of a deficiency at the level of medium-chain acyl-CoA dehydrogenase.

Pharmacokinetics of cefoxitin administered by i.v. infusion to patients with a pleural effusion

The pharmacokinetics of cefoxitin was studied in 6 healthy volunteers and in 5 patients with a pleural effusion after administration of a single dose of 30 mg/kg i.v. infusion. The serum and pleural fluid concentrations of cefoxitin were determined microbiologically. The elimination half-life of the antibiotic from pleural fluid in all cases was 2-3 fold longer than from serum, which shows a difference between the kinetic elimination processes of the antibiotic from the two fluids. The slow elimination of cefoxitin from pleural fluid facilitates its accumulation in this compartment during a multiple dosage regimen.

Pharmacokinetics of cefoxitin during haemofiltration

The pharmacokinetics of cefoxitin was studied in patients with renal impairment during haemofiltration and in the intervening periods after administration of 30 and 15 mg/kg of the drug, respectively. Different pharmacokinetic patterns were established during haemofiltration and in the interim period, with average elimination half-lives of 11.85 +/- 4.3 and 3.41 +/- 0.6 h, respectively. The average fraction of the cefoxitin dose eliminated in haemofiltration was 0.62 +/- 0.11, more than that established in haemodialysis. In patients with terminal renal impairment undergoing haemofiltration every 48 h, a dose of 15 or 30 mg/kg is recommended at the start and at the end of each haemofiltration session.

Pharmacokinetics of cefoxitin administered intramuscularly to rabbits with experimentally-induced renal impairment

The pharmacokinetics of Cefoxitin were studied in rabbits with normal renal function and with varying degrees of renal impairment induced experimentally by uranyl nitrate. All animals received a single intramuscular (i.m.) dose of 40 mg kg-1 of the antibiotic. The concentrations of Cefoxitin were determined in plasma, urine, and bile by a microbiologic plate diffusion method. The antibiotic follows a two-compartment open kinetic model. In rabbits with renal impairment there is a decrease in alpha, beta, K12, K21, Ka and an increase in Vd and the (AUC)infinity zero with respect to the values obtained for rabbits with normal renal function. Linear relationships are established between log beta and log K13 and the serum creatinine. Biliary excretion of Cefoxitin is increased in states of renal impairment. A linear relationship is established between the percentage of the dose excreted in the bile and the serum creatinine.

Late onset type of propionic acidaemia: case report and biochemical studies

A late-onset case of propionic acidaemia with favourable response to restriction of dietary protein is described. During a keto-acidotic crisis, this patient demonstrated unexpectedly low concentrations of propionic acid and glycine in blood and urine but increased urinary output of some secondary metabolites.

Disposition of cefoxitin in patients with ascites

The pharmacokinetics of Cefoxitin was studied in 8 cirrhotic patients with ascites after i.v. administration of a single 30 mg/kg dose. Concentrations of cefoxitin in serum and in ascitic fluid were determined simultaneously and by a microbiologic plate diffusion method. The antibiotic followed a two-compartment open kinetic model. In ascitic fluid, Cefoxitin reached its maximum concentration of 32.80 +/- 13,78 micrograms/ml 2 h after administration. The mean elimination constant from ascitic fluid was 0.201 +/- 0.008 h(-1), significantly lower (p less than 0.05) than the slow disposition phase constant (beta = 0.556 +/- 0.17 h(-1)). At the dose studied and with a dosage interval of 8 h, the level of antibiotic in the ascitic fluid would be maintained at a value greater than the MIC of most cefoxitin-sensitive organisms.

Disposition of cefoxitin in the elderly

The pharmacokinetics off cefoxitin were studied after a single i.v. and i. m. dose of 15 mg/kg of cefoxitin to 15 younger people (15-55 years) and to 16 geriatric patients (66-94 years). The kinetics of the antibiotic follow an open two-compartment model for both administration routes. After i.m. administration of the antibiotic, there are modifications in the distribution with respect to i.v. administration, and there is a decrease in beta K21 and as a consequence, an increase in Vp. In geriatric patients, pharmacokinetic modifications take place with respect to those recorded in the younger people in both administration routes, there being a decrease in the following pharmacokinetic parameters: alpha, beta, K12, K21, K13 and Clp, together with an increase in the apparent distribution volume Vdss. A linear relationship has been established between the constant beta and the age of the patient. In spite of the pharmacokinetic modifications observed as a function of age, given the wide safety margin of the antibiotic, it is not necessary to modify the dosage regimen of cefoxitin in geriatric patients.

Pharmacokinetics of cefoxitin in patients with normal or impaired renal function

The pharmacokinetics of cefoxitin have been determined after a single i.v. injection of 15 mg/kg body weight in 10 patients with normal renal function and 20 patients with varying degrees of renal impairment. The kinetics of the antibiotic followed an open two-compartment model. In patients with normal renal function the following pharmacokinetic parameters were found: alpha = 8.66 h-1 beta = 1.21 h-1 K12 = 3.47 h-1 K21 = 3.17 h-1 K13 = 3.15 h-1 Vc = 4.24 l. Vp = 4.87 l. Vdss = 9.11 l. In the patients with renal impairment there was a significant decrease in alpha, beta, K12, K21 and K13, and an increase in the apparent volume of distribution. The degree of plasma protein binding in patients with normal renal function was 73.6% and this was diminished in patients with renal impairment. A linear relationship between K13 of cefoxitin and creatinine clearance was demonstrated. The dosage regimen for patients with renal impairment should be adjusted by modifying the dosage interval whilst maintaining the amount administered.

Pharmacokinetics of cefoxitin in patients undergoing hemodialysis

The parmacokinetics of Cefoxitin were studied after an i.v. administration of 15 mg/kg body weight in 17 patients with terminal renal impairment, 10 of which were undergoing 6 hr hemodialysis sessions. The average pharmokinetic parameters obtained from this kind of patient were the following: alpha = 2.88 hr-1 beta = 0.18 hr-1 K12 = 1.43 hr-1 K21 = 1.04 hr-1 K13 = 0.53 hr-1 Vc = 8.23 l Vp = 11.61 l Vdss = 19.84 l. The amounts of the antibiotic in the central and peripheric compartments are established together with the amount of the antibiotic eliminated as a function of time. The pharmacokinetic parameters are significantly different from those established in the period between dialysis sessions, and thus, the elimination constant reaches a value of 0.28 h-1. The degree of plasma protein binding of Cefoxitin is 41.46% during the hemodialysis sessions. A dosage regimen is programmed as a function of the pharmacokinetic parameters established for this kind of patient. It is recommended that an i.v. dose of 15 mg/kg body weight should be administered at the beginning and end of each dialysis session lasting 6 hours, when the periods between the sessions are 48 hours.

Morbidity and mortality in diabetics in the Framingham population. Sixteen year follow-up study

In a sixteen year follow-up study in Framingham, it was found that diabetics in general show an increased morbidity and mortality from all cardiovascular causes. Insulin-treated diabetic women showed the greatest relative mortality from coronary heart disease. Diabetics were found to have higher lipid values, more hypertension and more obesity, even prior to diagnosis. When all the associated risk factors, individually or together, were taken into consideration their presence could not entirely explain the increase in cardiovascular morbidity and mortality experienced by the diabetic. An as yet unknown factor appears to be present in diabetics that could be responsible for much of the higher incidence of cardiovascular complications in diabetics.

Diminished serum insulin response to glucose in genetic prediabetic males with normal glucose tolerance

Serum immunoreactive insulin (IRI), plasma free fatty acids, and blood glucose were measured during an intravenous, an oral, and a cortisone-primed oral glucose tolerance test in each of eleven normal and five prediabetic (offspring of two diabetic parents) nonobese males, age twentyfive to thirty-four years. All normals and prediabetics had entirely normal blood glucose levels during each of the three tests. There were no significant differences between mean levels of serum insulin at any time period in any of the three types of tests. Serum IRI and blood glucose were significantly correlated in both normal and prediabetic groups during each of the three types of glucose tolerance tests. A linear regression equation of serum IRI (y) on blood glucose (x) was computed as an index for each type of test for each group and the regression coefficients (IRI in µU./ml per mg. per cent blood glucose) compared. A significantly lower slope was found for the oral and the cortisoneprimed oral glucose tolerance test in the prediabetic group. This suggests a diminished insulin secretory response to glucose in prediabetics who still maintained normal glucose tolerance. There was no evidence of a delay in the rise of serum insulin following a glucose load. There were no significant differences in mean plasma free fatty acids during each glucose tolerance test comparing prediabetics to normals. DIABETES 17:17-26, January, 1968.