Evaluation of Theophylline, Valproic Acid and Phenytoin by the CEDIA Method / 대한임상병리학회지

BACKGROUND: CEDIA is a newly developed method for therapeutic drug monitoring (TDM) and has some merits such as easy application to routine chemical analyzers, rapid and precise quantitation even in low concentrations and less cross reactivity. We evaluated the CEDIA(epsilon) (Microgenics Co., CA, USA) in measurement of theophyllin, valproic acid and phenytoin levels using 502X(epsilon) (A & T, Tokyo, Japan) and compared the results to those of the TDx(epsilon) (Abbott Laboratories, IL, USA) in order to assess the utility of the CEDIA(epsilon). METHODS: We evaluated the performance of 502X(epsilon) in the aspects of the within-runs and the between-runs precision, linearity, and carry-over. We compared the results of the CEDIA(epsilon) reagent with those of TDx(epsilon). The control materials (Bio-Rad TDM control level 1 and level 3; Bio-Rad laboratories, CA, USA) and clinical specimens were used for these studies. RESULTS: The coefficients of variation (CV) for the within-run and the between-run imprecision of 502X(epsilon) were 2.0-7.6% and 4.0-6.5%, respectively. The carry-over rate for theophyllin, valproic acid and phenytoin was 1.33%, 0.45% and 0.53%, respectively. The linearity (r(2)) of theophyllin, valproic acid and phenytoin was 0.9941, 0.9983 and 0.9947, respectively. The correlation coefficients (r) of theophyllin, valproic acid and phenytoin levels of CEDIA(epsilon), with those determined by the TDx(epsilon), were 0.9730, 0.9703 and 0.9695, respectively (P<0.001). CONCLUSIONS: The recentlydeveloped CEDIA(epsilon) proved to be highly precise and linear for quantitative analysis of theophyllin, phenytoin and valproic acid. Correlations with TDx(epsilon) were significantly high. CEDIA(epsilon) was thought to be clinically useful for TDM.

Plasma Glucose and Insulin Changes during IV Theophyline Therepy in Preterm Infants with Apnea / 대한주산의학회잡지

PURPOSE: The purpose of this study was to evaluate the effects of theophylline in preterm infants with apnea on glucose homeostasis and insulin values. METHOD: In this prospective study, level of glucose and insulin were measured from peripheral blood of 8 neonates(1,450+/-114gm, 31+/-2.1week), who were admitted from April 1, 1997 to July 30, 1997 in Neonatal Intensive Care Unit of Wonkwang University Hospital, for apnea of prematurity(> 20 sec with bradycardia and/or cyanosis) were given aminophylline intravenously. Blood samples were collected at pretreatment, posttreatment 2hours, 1-2days, 3-4days, 5-7days and posttreatment 48hours, and compare to those of the 8 control neonates(1,711+/-232gm, 32+/-1.7week). RESULTS: The results were as follows: 1) Plasma glucose values were significantly higher in the treatment group than those of the control group at 1-2days(104.67+/-20.39mg/dL vs 83.43+/-15.86mg/dL) and 3-4days(111.0+/-32.39mg/dL vs 79.25+/-14.03mg/dL)(p 125mg/dL). 3) The mean posttreatment glucose levels drawn at 48hours after discontinuation of theophylline was significantly decreased to the values of pretreatment values compared to those of the 1-2days and 3-4days(p 125mg/dL) was not noted. So, plasma glucose may not need to be monitored in preterm apneic infants receiving theophylline. But, further studies are need to elucidate the effect of theophylline considering the serum toxic level of theophylline.