IMMEDIATE ANTICONVULSIVE DRUG MONITORING IN MANAGEMENT OF EPILEPSY
1
39 We interpreted our findings as indicating that babies recognised situational changes and find separation from their mothers stressful. The fall in forehead temperature we recorded resembled temperature patterns in adults in an experimental stressful working environment. Developmental Psychology Research Laboratory, National Children’s Medical Research Center, Tokyo 154, Japan KEIKO MIZUKAMI NOBORU KOBAYASHI Institute of Engineering Mechanics, Tsukuba University HIROO IWATA Department of Industrial Engineering, Tokyo University TAKEMOCHI ISHII IMMEDIATE ANTICONVULSIVE DRUG MONITORING IN MANAGEMENT OF EPILEPSY SIR,-Monitoring of anticonvulsive drugs is recognised as an essential tool in the management of patients with epilepsy." However, several days or even weeks can elapse before the result is available to the physician, so that he has either to rely on clinical evidence alone to decide on treatment or he has to defer making such a decision. This may delay the attainment of the best regimen and mean extra visits to the outpatient clinic and increased costs. An immediate on-site monitoring service has been in operation at our centre for epilepsy since 1983. On arrival of the patient at the outpatient clinic serum anticonvulsive drugs are assayed within 15 min. The results are thus available to the physician while the patient is still in the consulting room. Carbamazepine, phenytoin, and phenobarbitone are assayed by enzyme immunoassay (’EMIT’, Syva) and polarisation fluoro- immunoassay (’TDX’, Abbott). Many of our outpatients are referred by other hospital physicians. Most have intractable epilepsy and the potential for improving seizure control is limited. The case notes of patients who attended one consultant’s clinic (J. 0.) for the first time in the year before (control period, n = 32) and the year after (test period, n = 53) the inauguration of the immediate monitoring service were reviewed. All 85 patients were taking phenytoin, carbamazepine, pheno- barbitone, or primidone singly or in combination. Most were seen only once but 6 patients (4 with partial and 2 with generalised epilepsy) in each period met the study criterion that a treatment programme had been implemented, the object of which included establishing patients on a predetermined drug regimen with doses guided by clinical effectiveness and serum drug levels. The case records of these patients were analysed further by J. W. A. S. S., who was unaware of the purpose of the study. Although the number of patients in this retrospective study was small, we could demonstrate the effectiveness of the monitoring service in patient management with significant reductions in time between first consultation and achieving the treatment objective, number of consultations, number of letters to referring physician, and number of drugs assayed (table). Other benefits are less easy to quantify but from our experience the rapid assay has led to greater MANAGEMENT OF SEVERE EPILEPSY BEFORE AND AFTER IMPLEMENTATION OF IMMEDIATE ANTICONVULSIVE DRUG MONITORING SERVICE patient satisfaction in the treatment procedure, an easier check on compliance and the accuracy of laboratory procedures, and more rapid attention to toxic symptoms, and identification of changes in patient metabolism and of drug interactions. We emphasise that these patients have the most severe forms of epilepsy; in patients for whom complete seizure control is attainable, the benefits would be even greater. The cost per patient of each drug assay has been slightly higher since the immediate service was introduced, largely because of the smaller batch sizes. However, the extra cost is negligible in comparison to the saving in physician’s and patient’s time, and administrative costs. Our study provides extra support for the recommendations that the management of patients with difficult epilepsy should be organised around epilepsy clinics where all necessary facilities are immediately available. Chalfont Centre for Epilepsy, Chalfont St Peter, Gerrards Cross, Bucks SL9 0RJ PHILIP N. PATSALOS JOSEMIRE W. A. S. SANDER JOLYON OXLEY Department of Chemical Pathology, National Hospital, London WC1 PETER T. LASCELLES 1. Kutt H, Penry JK. Usefulness of blood levels of antiepileptic drugs. Arch Neurol 1974, 31: 283-88. 2. Eadie MJ. Plasma level monitoring of anticonvulsants. Clin Pharmacokinet 1976; 1: 52-66. 3. Reynolds EH. Serum levels of anticonvulsant drugs: Interpretation and clinical value. Pharmacol Ther 1980; 8: 217-35. 4. Perucca E, Richens A. Antiepileptic drugs: Clinical aspects. In: Richens A, Marks V, eds. Therapeutic drug monitoring. Edinburgh: Churchill Livingstone, 1981: 320-48. 5. Report to the Department of Health and Social Security of the Working Group on Services for Patients with Epilepsy. London: HM Stationery Office, 1986. GROUP-SPECIFIC COMPONENT AND HIV INFECTION SIR,-Susceptibility to HIV infection and rates of disease progression may depend upon genetic characteristics. Dr Eales and her colleagues (May 2, p 999) present evidence linking HIV infection with group specific component (Gc) phenotype in homosexuals. Another group at high risk of HIV infection are haemophiliacs, exposed to HIV-contaminated factor VIII. We have studied Gc phenotype and HIV infection in 81 haemophiliacs. Gc phenotyping was done by isoelectric focusingl followed by immunofixation with anti-Gc antibody and silver staining.2 HIV antibody tests were done by a competitive ELISA (Wellcome) and positive results were confirmed by an alternative ELISA and by immunofluorescence. Coded serum or plasma, stored at-20°C for up to 5 years, had an equal volume of 6 mol/1 urea added to inactivate HIV. Urea treatment inactivated at least five logs of HIV infectivity and reverse transcriptase activity (unpublished), thus permitting Gc phenotyping outside containment facilities. Urea-treated samples could be tested after storage at-20°C for up to 3 weeks. The results are presented in the table.
Transcript of IMMEDIATE ANTICONVULSIVE DRUG MONITORING IN MANAGEMENT OF EPILEPSY
39
We interpreted our findings as indicating that babies recognisedsituational changes and find separation from their mothers stressful.The fall in forehead temperature we recorded resembledtemperature patterns in adults in an experimental stressful workingenvironment.
Developmental Psychology Research Laboratory,National Children’s Medical Research Center,Tokyo 154, Japan
KEIKO MIZUKAMINOBORU KOBAYASHI
Institute of Engineering Mechanics,Tsukuba University HIROO IWATA
Department of Industrial Engineering,Tokyo University TAKEMOCHI ISHII
IMMEDIATE ANTICONVULSIVE DRUGMONITORING IN MANAGEMENT OF EPILEPSY
SIR,-Monitoring of anticonvulsive drugs is recognised as anessential tool in the management of patients with epilepsy."However, several days or even weeks can elapse before the result isavailable to the physician, so that he has either to rely on clinicalevidence alone to decide on treatment or he has to defer making sucha decision. This may delay the attainment of the best regimen andmean extra visits to the outpatient clinic and increased costs. Animmediate on-site monitoring service has been in operation at ourcentre for epilepsy since 1983.On arrival of the patient at the outpatient clinic serum
anticonvulsive drugs are assayed within 15 min. The results are thusavailable to the physician while the patient is still in the consultingroom. Carbamazepine, phenytoin, and phenobarbitone are assayedby enzyme immunoassay (’EMIT’, Syva) and polarisation fluoro-immunoassay (’TDX’, Abbott).Many of our outpatients are referred by other hospital physicians.
Most have intractable epilepsy and the potential for improvingseizure control is limited. The case notes of patients who attendedone consultant’s clinic (J. 0.) for the first time in the year before(control period, n = 32) and the year after (test period, n = 53) theinauguration of the immediate monitoring service were reviewed.All 85 patients were taking phenytoin, carbamazepine, pheno-barbitone, or primidone singly or in combination. Most were seenonly once but 6 patients (4 with partial and 2 with generalisedepilepsy) in each period met the study criterion that a treatmentprogramme had been implemented, the object of which includedestablishing patients on a predetermined drug regimen with dosesguided by clinical effectiveness and serum drug levels. The caserecords of these patients were analysed further by J. W. A. S. S.,who was unaware of the purpose of the study.Although the number of patients in this retrospective study was
small, we could demonstrate the effectiveness of the monitoringservice in patient management with significant reductions in timebetween first consultation and achieving the treatment objective,number of consultations, number of letters to referring physician,and number of drugs assayed (table). Other benefits are less easy toquantify but from our experience the rapid assay has led to greater
MANAGEMENT OF SEVERE EPILEPSY BEFORE AND AFTER
IMPLEMENTATION OF IMMEDIATE ANTICONVULSIVE DRUG
MONITORING SERVICE
patient satisfaction in the treatment procedure, an easier check oncompliance and the accuracy of laboratory procedures, and morerapid attention to toxic symptoms, and identification of changes inpatient metabolism and of drug interactions. We emphasise thatthese patients have the most severe forms of epilepsy; in patients forwhom complete seizure control is attainable, the benefits would beeven greater.The cost per patient of each drug assay has been slightly higher
since the immediate service was introduced, largely because of thesmaller batch sizes. However, the extra cost is negligible in
comparison to the saving in physician’s and patient’s time, andadministrative costs. Our study provides extra support for therecommendations that the management of patients with difficultepilepsy should be organised around epilepsy clinics where all
necessary facilities are immediately available.
Chalfont Centre for Epilepsy,Chalfont St Peter, Gerrards Cross,Bucks SL9 0RJ
PHILIP N. PATSALOS
JOSEMIRE W. A. S. SANDERJOLYON OXLEY
Department of Chemical Pathology,National Hospital,London WC1 PETER T. LASCELLES
1. Kutt H, Penry JK. Usefulness of blood levels of antiepileptic drugs. Arch Neurol 1974,31: 283-88.
2. Eadie MJ. Plasma level monitoring of anticonvulsants. Clin Pharmacokinet 1976; 1:52-66.
3. Reynolds EH. Serum levels of anticonvulsant drugs: Interpretation and clinical value.Pharmacol Ther 1980; 8: 217-35.
4. Perucca E, Richens A. Antiepileptic drugs: Clinical aspects. In: Richens A, Marks V,eds. Therapeutic drug monitoring. Edinburgh: Churchill Livingstone, 1981:320-48.
5. Report to the Department of Health and Social Security of the Working Group onServices for Patients with Epilepsy. London: HM Stationery Office, 1986.
GROUP-SPECIFIC COMPONENT AND HIVINFECTION
SIR,-Susceptibility to HIV infection and rates of disease
progression may depend upon genetic characteristics. Dr Eales andher colleagues (May 2, p 999) present evidence linking HIVinfection with group specific component (Gc) phenotype inhomosexuals. Another group at high risk of HIV infection arehaemophiliacs, exposed to HIV-contaminated factor VIII. Wehave studied Gc phenotype and HIV infection in 81 haemophiliacs.Gc phenotyping was done by isoelectric focusingl followed by
immunofixation with anti-Gc antibody and silver staining.2 HIVantibody tests were done by a competitive ELISA (Wellcome) andpositive results were confirmed by an alternative ELISA and byimmunofluorescence.Coded serum or plasma, stored at-20°C for up to 5 years, had an
equal volume of 6 mol/1 urea added to inactivate HIV. Ureatreatment inactivated at least five logs of HIV infectivity and reversetranscriptase activity (unpublished), thus permitting Gc
phenotyping outside containment facilities. Urea-treated samplescould be tested after storage at-20°C for up to 3 weeks. The resultsare presented in the table.
