Prenatal exposure to antibiotics, cesarean section and risk of childhood obesity.

BACKGROUND/OBJECTIVES: Cesarean section (CS) and antibiotic use during pregnancy may alter normal maternal-offspring microbiota exchange, thereby contributing to aberrant microbial colonization of the infant gut and increased susceptibility to obesity later in life. We hypothesized that (i) maternal use of antibiotics in the second or third trimester of pregnancy and (ii) CS are independently associated with higher risk of childhood obesity in the offspring. SUBJECTS/METHODS: Of the 727 mothers enrolled in the Northern Manhattan Mothers and Children Study, we analyzed the 436 mother-child dyads followed until 7 years of age with complete data. We ascertained prenatal antibiotic use by a questionnaire administered late in the third trimester, and delivery mode by medical record. We derived age- and sex-specific body mass index (BMI) z-scores using the CDC SAS Macro, and defined obesity as BMI z⩾95th percentile. We used binary regression with robust variance and linear regression models adjusted for maternal age, ethnicity, pre-gravid BMI, maternal receipt of public assistance, birth weight, sex, breastfeeding in the first year and gestational antibiotics or delivery mode. RESULTS: Compared with children not exposed to antibiotics during the second or third trimester, those exposed had 84% (33-154%) higher risk of obesity, after multivariable adjustment. Second or third trimester antibiotic exposure was also positively associated with BMI z-scores, waist circumference and % body fat (all P<0.05). Independent of prenatal antibiotic usage, CS was associated with 46% (8-98%) higher offspring risk of childhood obesity. Associations were similar for elective and non-elective CS. CONCLUSIONS: In our cohort, CS and exposure to antibiotics in the second or third trimester were associated with higher offspring risk of childhood obesity. Future studies that address the limitations of our study are warranted to determine if prenatal antibiotic use is associated with offspring obesity. Research is also needed to determine if alterations in neonatal gut microbiota underlie the observed associations.

Barriers to the delivery of optimal antidiabetic therapy in the Middle East and Africa.

BACKGROUND: The prevalence of type 2 diabetes is increasing worldwide, but developing nations will bear a disproportionate share of this burden. Countries in the Middle East and Africa are in a state of transition, where marked disparities of income and access to education and healthcare exist, and where the relatively young populations are being exposed increasingly to processes of urbanisation and adverse changes in diet that are fuelling the diabetes epidemic. Optimising diabetes care in these nations is crucial, to minimise the future burden of complications of diabetes. METHODS: We have reviewed the barriers to effective diabetes care with special relevance to countries in this region. RESULTS: The effects of antidiabetic treatments themselves are unlikely to differ importantly in the region compared with elsewhere, but economic inequalities within countries restrict access to newer treatments, in particular. Values relating to family life and religion are important modifiers of the physician-patient interaction. Also, a lack of understanding of diabetes and its treatments by both physicians and patients requires more and better diabetes education, delivered by suitably qualified health educators. Finally, sub-optimal processes for delivery of care have contributed to a lack of proper provision of testing and follow-up of patients in many countries. CONCLUSION: Important barriers to the delivery of optimal diabetes care exist in the Middle East and Africa.

The effect of vildagliptin relative to sulphonylureas in Muslim patients with type 2 diabetes fasting during Ramadan: the VIRTUE study.

AIMS: To assess, in a real-world setting, the effect of vildagliptin compared with sulphonylurea (SU) treatment on hypoglycaemia in Muslim patients with type 2 diabetes mellitus (T2DM) fasting during Ramadan. METHODS: This multinational, non-interventional study, conducted in Asia and the Middle East, included Muslim adult patients with T2DM who received treatment with vildagliptin or SU as add-on to metformin or monotherapy. During a ~16-week observation period, data were collected up to 6 weeks before and 6 weeks after Ramadan fasting. The primary study objective was to compare the proportion of patients with ≥ 1 hypoglycaemic event (HE) during fasting. RESULTS: Of > 1300 patients enrolled in the study, 684 were treated with vildagliptin and 631 with SUs. Significantly fewer patients experienced ≥ 1 HE with vildagliptin compared with those receiving SUs (5.4% vs. 19.8%, respectively; p < 0.001); no vildagliptin-treated patients reported a grade 2 HE, vs. 4 SU-treated patients (p = 0.053). Mean HbA1c changes from baseline were vildagliptin: -0.24%, SUs: +0.02% (p < 0.001). Mean body weight reductions from baseline were vildagliptin: -0.76 kg, SUs: -0.13 kg (p < 0.001). A higher proportion of SU-treated patients experienced adverse events (AEs) compared with vildagliptin (22.8% vs. 10.2%). This difference was driven by hypoglycaemia as the most common AE. CONCLUSIONS: In this real-world study of fasting Muslim patients with T2DM, vildagliptin was associated with significantly fewer hypoglycaemic episodes compared with SU therapy. This outcome is particularly meaningful when viewed in the context of good glycaemic and weight control observed in vildagliptin-treated patients. Vildagliptin was well tolerated in this patient population.

Barriers to the delivery of diabetes care in the Middle East and South Africa: a survey of 1,082 practising physicians in five countries.

AIMS: Developing countries face a high and growing burden of type 2 diabetes. We surveyed physicians in a diverse range of countries in the Middle East and Africa (Egypt, Kingdom of Saudi Arabia, United Arab Emirates, South Africa and Lebanon) with regard to their perceptions of barriers to type 2 diabetes care identified as potentially important in the literature and by the authors. METHODS: One thousand and eighty-two physicians completed a questionnaire developed by the authors. RESULTS: Most physicians enrolled in the study employed guideline-driven care; 80-100% of physicians prescribed metformin (with lifestyle intervention, where there are no contraindications) for newly diagnosed type 2 diabetes, with lifestyle intervention alone used where metformin was not prescribed. Sulfonylureas were prescribed widely, consistent with the poor economic status of many patients. About one quarter of physicians were not undertaking any form of continuing medical education, and relatively low proportions of practices had their own diabetes educators, dieticians or diabetic foot specialists. Physicians identified the deficiencies of their patients (unhealthy lifestyles, lack of education and poor diet) as the most important barriers to optimal diabetes care. Low-treatment compliance was not ranked highly. Access to physicians did not appear to be a problem, as most patients were seen multiple times per year. CONCLUSIONS: Physicians in the Middle East and South Africa identified limitations relating to their patients as the main barrier to delivering care for diabetes, without giving high priority to issues relating to processes of care delivery. Further study would be needed to ascertain whether these findings reflect an unduly physician-centred view of their practice. More effective provision of services relating to the prevention of complications and improved lifestyles may be needed.

A prospective registry of European haemophilia B patients receiving nonacog alfa, recombinant human factor IX, for usual use.

Nonacog alfa, a recombinant factor IX (FIX) used for the treatment of haemophilia B, was approved in Europe in 1998. In accordance with European Medicines Agency requirements, a registry study was conducted from 2002 to 2009. A reformulated iso-osmotic version was approved for European use in 2007. This study was conducted to evaluate the safety of nonacog alfa in a usual care setting, and provide clinical trial and postmarketing surveillance data support. This open-label, non-interventional, prospective observational cohort study (registry) comprised 52 sites in nine European countries. Patients with haemophilia B receiving nonacog alfa in either formulation for prevention or treatment were followed on a usual care schedule. A total of 218 patients were enrolled, of whom 66 (30.3%) were <18 years of age. Haemophilia severity was evenly distributed, with baseline FIX activity of <1%, 1-5% and >5% in 33.3%, 36.6% and 30.1% of patients, respectively. One hundred thirty-eight patients received the original formulation alone; 80 switched to or received only the new formulation. There was a low incidence of events of special interest (ESIs), with less-than-expected therapeutic effect in five patients (2.2%), inhibitor development in two (0.9%), thrombosis in one (0.5%) and allergic events in eight (3.7%). These accounted for the majority of the 15 serious AEs reported in six patients. Six patients discontinued because of AEs, primarily related to hypersensitivity. Nonacog alfa was shown to be safe for the treatment of haemophilia B, with a low incidence of serious AEs and ESIs.

Optimising the medical management of hyperglycaemia in type 2 diabetes in the Middle East: pivotal role of metformin.

AIMS: Increases in the prevalence of type 2 diabetes will likely be greater in the Middle East and other developing countries than in most other regions during the coming two decades, placing a heavy burden on regional healthcare resources. METHODOLOGY: Medline search, examination of data from major epidemiological studies in the Middle Eastern countries. RESULTS: The aetiology and pathophysiology of diabetes appears comparable in Middle Eastern and other populations. Lifestyle intervention is key to the management of diabetes in all type 2 diabetes patients, who should be encouraged strongly to diet and exercise. The options for pharmacologic therapy in the management of diabetes have increased recently, particularly the number of potential antidiabetic combinations. Metformin appears to be used less frequently to initiate antidiabetic therapy in the Middle East than in other countries. Available clinical evidence, supported by current guidelines, strongly favours the initiation of antidiabetic therapy with metformin in Middle Eastern type 2 diabetes patients, where no contraindications exist. This is due to its equivalent or greater efficacy relative to other oral antidiabetic treatments, its proven tolerability and safety profiles, its weight neutrality, the lack of clinically significant hypoglycaemia, the demonstration of cardiovascular protection for metformin relative to diet in the UK Prospective Diabetes Study and in observational studies, and its low cost. Additional treatments should be added to metformin and lifestyle intervention as diabetes progresses, until patients are receiving an intensive insulin regimen with or without additional oral agents. CONCLUSIONS: The current evidence base strongly favours the initiation of antidiabetic therapy with metformin, where no contraindications exist. However, metformin may be under-prescribed in the Middle East.

Insulin-like growth factor system abnormalities in hepatitis C-associated osteosclerosis. Potential insights into increasing bone mass in adults.

Hepatitis C-associated osteosclerosis (HCAO) is a rare disorder characterized by a marked increase in bone mass during adult life. Despite the rarity of HCAO, understanding the mediator(s) of the skeletal disease is of great interest. The IGFs-I and -II have potent anabolic effects on bone, and alterations in the IGFs and/or IGF-binding proteins (IGFBPs) could be responsible for the increase in bone formation in this disorder. Thus, we assayed sera from seven cases of HCAO for IGF-I, IGF-II, IGF-IIE (an IGF-II precursor), and IGFBPs. The distribution of the serum IGFs and IGFBPs between their ternary ( approximately 150 kD) and binary (approximately 50 kD) complexes was also determined to assess IGF bioavailability. HCAO patients had normal serum levels of IGF-I and -II, but had markedly elevated levels of IGF-IIE. Of the IGFBPs, an increase in IGFBP-2 was unique to these patients and was not found in control hepatitis C or hepatitis B patients. IGF-I and -II in sera from patients with HCAO were carried, as in the case of sera from control subjects, bound to IGFBP-3 in the approximately 150-kD complex, which is retained in the circulation. However, IGF-IIE was predominantly in the approximately 50-kD complex in association with IGFBP-2; this complex can cross the capillary barrier and access target tissues. In vitro, we found that IGF-II enhanced by over threefold IGFBP-2 binding to extracellular matrix produced by human osteoblasts and that in an extracellular matrix-rich environment, the IGF-II/IGFBP-2 complex was as effective as IGF-II alone in stimulating human osteoblast proliferation. Thus, IGFBP-2 may facilitate the targeting of IGFs, and in particular IGF-IIE, to skeletal tissue in HCAO patients, with a subsequent stimulation by IGFs of osteoblast function. Our findings in HCAO suggest a possible means to increase bone mass in patients with osteoporosis.

Retrospective comparative analysis of cardiovascular implantable electronic device infections with and without the use of antibacterial envelopes.

BACKGROUND: Cardiovascular implantable electronic device (CIED) infections are associated with morbidity and mortality. Peri-operative systemic intravenous antibiotic prophylaxis reduces the rate of CIED infections. AIGISRx, a polymer envelope implanted with the CIED, releases minocycline and rifampin, and has been introduced to reduce infections. METHODS: Retrospective review of 184 patients who underwent CIED implantation was conducted. Ninety-two patients were implanted with an AIGISRx envelope (AIGISRx group) and 92 patients were not implanted with an AIGISRx envelope (control group). Data were collected on demographics and risk factors for CIED infections (i.e. congestive heart failure, renal insufficiency, chronic kidney disease, oral anticoagulant use, chronic steroid use, need for lead replacement or revision, temporary pacing, early re-intervention, and having more than two leads in place). Rates of implantation success, major infections and mortality were compared between the AIGISRx group and the control group. RESULTS: The AIGISRx group had longer hospitalizations (6.8±10.7 days vs 3.1±5.2 days; P=0.001), higher chronic corticosteroid use, higher rates of replacement or revision (51.1% vs 8.7%; P=0.001), and a greater proportion of devices with more than two intracardiac leads (42.4% vs 29.3%; P=0.03) than the control group. Successful implantation occurred in 97% of patients in both groups. Major infection was seen in 5.4% of cases in the AIGISRx group and 1.1% of cases in the control group (P=0.048). Device removal was conducted in 3.3% of cases in the AIGISRx group compared with 1.1% of cases in the control group (P=0.16). There were two deaths in the AIGISRx group. Organisms cultured were meticillin-resistant Staphylococcus aureus, meticillin-susceptible S. aureus and Enterococcus faecalis. CONCLUSION: The AIGISRx group had higher rates of major infection but also higher risk factors compared with the control group. The rate of device extraction and CIED-related mortality was higher in the AIGISRx group than in the control group.

Effect of target-enriched multiplex polymerase chain reaction on patient outcomes and costs during the 2013-14 influenza season.

The US Centers for Disease Control and Prevention recommends the initial use of rapid antigen influenza diagnostic test (RIDT) for the detection of influenza A (H1N1-09). Nasopharyngeal samples were tested from 246 patients for H1N1-09 using target-enriched multiplex polymerase chain reaction (TEM-PCR), of which 163 were additionally tested via RIDT. RIDTs had a sensitivity of 18.7% compared with TEM-PCR as the reference standard. Patients with false-negative RIDTs were withheld from 111 days of oseltamivir and 65 days of isolation. Patients negative for H1N1 via TEM-PCR had antiviral therapy immediately stopped, thereby evading 408 days of oseltamivir and 315 days of unnecessary isolation. This cost avoidance saved US$208,982.

Immunologic factors: the major risk for decreased long-term renal allograft survival.

BACKGROUND: Both antigen-dependent (immunologic) and non-antigen-dependent (nonimmunologic) factors have been implicated in long-term renal allograft loss. Differentiating between these two factors is important because prevention strategies differ. METHODS: To isolate the importance of these 2 factors, we studied long-term actuarial graft survival in a cohort of adult kidney recipients who underwent transplants at a single institution between January 1, 1984 and October 31, 1998. Excluded were recipients with graft loss as a result of death with function, technical failure, primary nonfunction, and recurrent disease, leaving 1587 recipients (757 cadaver [CAD], 830 living donor [LD]) who would be at risk for graft loss secondary to both immunologic and nonimmunologic factors. These recipients were analyzed in the following 2 groups: those treated for a previous episode of acute rejection (AR) (Group1; n = 588; 328 CAD, 260 LD) and those with no AR (Group 2: n = 999; 429 CAD, 570 LD). Actuarial graft survival and causes of graft loss were determined for each group. Presumably, graft loss in Group 1 would be caused by immunologic and nonimmunologic factors; graft loss in Group 2 would be caused primarily by nonimmunologic factors. RESULTS: The 10-year graft survival rate (censored for death with function, technical failure, primary nonfunction, and recurrent disease) in Group 2 was 91%. In contrast, the 10-year graft survival rate in Group 1 was 45% (P<0.001 vs. Group 2). Causes of graft loss in Group 2 were chronic rejection in 1.8% (3.0% CAD, 0.9% LD), de novo disease, 0.4%; sepsis, 0.2%; discontinuation of immunosuppressive therapy, 0.3%; and unknown, 0.6%. In contrast, 23.8% (29.9% CAD, 16.2% LD) of recipients in Group 1 had graft loss caused by chronic rejection (P = 0.001 vs. Group 2). CONCLUSIONS: This very low incidence of chronic rejection in recipients without previous AR suggests that immunologic factors are the main determinants of long-term kidney transplant outcome; nonimmunologic factors in isolation may have only a minimal impact on long-term graft survival.

Clinical application of the two-layer (University of Wisconsin solution/perfluorochemical plus O2) method of pancreas preservation before transplantation.

BACKGROUND: The two-layer method [University of Wisconson solution (UW)/perfluorochemical plus O2] for pancreas preservation has been demonstrated to be superior to simple UW storage alone in the canine model. For the first time, we applied the two-layer method to clinical whole-pancreas transplantation. METHODS: Pancreases were placed in the two-layer method in 10 cases and UW alone in 44 cases before transplant. The mean cold ischemic time was 16.5 hr in the two-layer group versus 18.1 hr in the UW group (P=NS). We compared the condition of graft at the time of reperfusion, and then 3 months posttransplant graft function and complications. RESULTS: At the time of reperfusion, no grafts in the two-layer group were edematous, compared with 10(23.3%) of 43 in the UW group (P=0.18). Seven (70%) of 10 grafts in the two-layer group obtained the best overall quality score, compared with 24(57.1%) of 42 in the UW group (P=0.72). Nine (90%) of 10 recipients in the two-layer group became insulin-independent during hospitalization, compared with 31(70.5%) of 44 in the UW group (P=0.26). Time to insulin independence was no different between the two groups. No pancreas grafts preserved by the two-layer method suffered acute rejection. Conclusions. The two-layer preservation method is feasible in human clinical transplantation. It was at least equivalent and may be superior to UW alone in both morphologic and functional assessment of the transplanted pancreas.

Ethylene glycol poisoning treated by intravenous 4-methylpyrazole.

A 19-year-old woman was admitted 45 min after ethylene glycol (EG) ingestion. The initial serum EG concentration was 1.34 g/l (21.6 mmol/l), the anion gap 14.5, and the osmolal gap 24. Renal function was preserved (serum creatinine 75.1 micromol/l). As the patient was seen soon after poisoning, before the development of metabolic acidosis, therapy with 4-methylpyrazole (4-MP) was proposed as an antidote. 4-MP was administered via the intravenous route (7 mg/kg as loading dose, followed by 3.6, 1.2, 0.6, and 0.6 mg/kg at intervals of 12 h). 4-MP alone was effective in preventing EG biotransformation to toxic metabolites (absence of metabolic acidosis and renal injury). Ethanol therapy, hemodialysis, and sodium bicarbonate administration were not required. The half-life of EG during 4-MP therapy was 11 h, with a mean EG renal clearance of 26.9 ml/min, and a total of 65.3 g EG was eliminated unchanged in the urine. 4-MP therapy was also well tolerated.

Amrinone for refractory cardiogenic shock following chloroquine poisoning.

Cardiac arrhythmias and circulatory collapse account for the high mortality reported after severe chloroquine poisoning. We have recently observed a 17-year-old man who ingested an 8 g chloroquine overdose. Cardiac arrest occurred within 1 h. Cardiogenic shock was refractory to epinephrine, dopamine and molar sodium lactate. Amrinone, a bipyridine analog, was then successfully used to improve haemodynamic conditions.

Porphyric neuropathy and hereditary delta-aminolevulinic acid dehydratase deficiency in an adult.

A man without a history of porphyric attacks developed a subacute motor neuropathy at the age of 63. At the same time the first signs of a myeloproliferative disorder were found. He had a homozygous deficiency of erythrocyte delta-aminolevulinic acid dehydratase (ALA-D) with autosomal recessive inheritance. Treatment with parenteral glucose and with hematin had a beneficial influence on the plasma ALA levels. The finding of a motor neuropathy with increased plasma levels of ALA but not of porphobilinogen (PBG) supports the potential role of ALA in the pathogenesis of porphyric neuropathy.

Inhibitory effects of solvent and solid-phase extraction residues on mixed lymphocyte cultures.

Residues from eight solvents/solvent mixtures before and after their passage through C18- bonded phase columns were assayed for cytostatic activity using mixed lymphocyte cultures (MLC). All residues, except those from acetonitrile, exhibited cytostatic activity (15%-35% MLC inhibition as measured by 3H-thymidine incorporation). Passage of solvents through bonded phase columns contributed an additional and significant cytostatic effect (19%-69% MLC inhibition). Pretreatment of columns with methanol led to further increases in the release of cytostatic residues from the columns, only when followed by less polar solvents (hexane, ethylacetate, etc.). It is concluded that residues from solid-phase extraction columns may interfere with subsequent cell culture-based assays for proliferative/antiproliferative activity.

The medical and economic consequences of automation in bacteriology: a case study in a French university hospital.

In a bacteriology laboratory where automated and non-automated procedures co-existed during the study period (1 year), patients were randomly assigned to each type of procedure and we observed the physicians behaviour as well as patients well-being in a surgical service using the results from the laboratory. Contrary to our expectations, the reduction in the time delay necessary to obtain information did not alter either the prescribing behaviour of physicians nor the welfare of patients. Besides, the gain in time was significantly lower than expected. We also discuss in detail the meaning and relevance of the results.

Glycated hemoglobin in insulinoma.

OBJECTIVE: To determine whether preoperative levels of glycated hemoglobin (GHb) are lower in patients with functioning insulinoma and, if so, whether a distinct separation of GHb values from those in control subjects might serve for diagnosis. METHODS: We examined preoperative GHb in consecutive patients (who had this measurement done) with surgically confirmed insulinoma for the period 1983 (when the current method became available for routine use) through 1996. Hemoglobin A(1) (HbA(1)) was measured by the Isolab Glyc-Affin Test System (normal range, 4 to 7%). We studied 64 patients with insulinoma (40 women and 24 men; median age, 47.5 years; age range, 21 to 79) and 38 control subjects (25 women and 13 men; median age, 42.5 years; age range, 20 to 83) considered not to have a hypoglycemic disorder on the basis of normal results of a supervised 72-hour fast. RESULTS: HbA(1) was significantly lower in patients with insulinoma (median, 4.7%; range, 2.7 to 6.9%) than in control subjects (median, 5.3%; range, 4.1 to 6.4%) (P<0.001, two-tailed rank sum test). Among 15 patients with insulinoma treated with diazoxide preoperatively, HbA(1) was higher (median, 4.8%; range, 4.2 to 6.9%) than in patients not treated with diazoxide (median, 4.6%; range, 2.7 to 5.7%), although the difference was not statistically significant (P = 0.08). CONCLUSION: Because of considerable overlap in HbA(1) values, no GHb value was diagnostic for insulinoma; however, 16 of 64 patients (25%) with insulinoma had HbA(1) values below the lowest value (4.1%) in control subjects. Thus, HbA(1) values less than 4.1% in patients with possible insulinoma are strongly indicative of that disorder.

Bile analysis of drugs in postmortem cases.

Bile is, in certain cases, collected together with blood from different sites (heart, brain, femoral), urine and other organs or matrices. This study reports comparative results obtained from the analysis of blood and bile for different drugs found: acetaminophen, amphetamine and related compounds, several antidepressants, several benzodiazepines, cocaine and its metabolites, dextropropoxyphene and its metabolite, hydroxyzine, methadone and metabolite, morphine and codeine, levomepromazine, thioridazine, propranolol, tramadol and its metabolite. Several findings are presented: (1) There were no significant differences in the levels of the compounds among the samples of blood obtained from different sites. (2) Levels in bile are generally several fold higher than those in blood. The mean bile to blood ratios vary from about 1 (for acetaminophen, amphetamine) to about 2000 (for desmethylclobazam). (3) In certain cases (16 over 44), although the drug or its metabolite was not detected in blood from different sites, it was detected in bile. As other authors had advocated, it is very useful to ask the pathologist to take the gall bladder with its contents together with the other samples, in order that the sample of bile can be used in the comprehensive toxicological analysis and therefore be complementary to the other fluids or matrices. An additional advantage for using bile is that the concentrations of drugs or their metabolites are generally several fold higher than their blood concentrations.

Potential use of a radioreceptor assay for the determination of benzodiazepine compounds in serum.

The clinical monitoring and intensive care of patients who have taken an overdose of a benzodiazepine require rapid and quantitative methods to assess benzodiazepine concentrations in biological fluids. A radioreceptor assay (RRA) permits the simultaneous measurement of the benzodiazepine molecules that bind to the receptor, providing a total estimate of all pharmacologically active forms of the drug(s) (parent drug and active metabolites). This study describes the development of an RRA for the determination of benzodiazepine compounds in serum using a lyophilized bovine brain cerebral cortex receptor preparation. The standard curves and the sensitivity of this RRA are determined for 20 different benzodiazepines and the specific antagonist flumazenil. The sensitivity ranges from 5 ng/mL for clonazepam to 3500 ng/mL for chlordiazepoxide. The IC50 values are significantly correlated (r = 0.81) with the lowest recommended therapeutic concentrations. The advantages and disadvantages of this RRA are discussed and compared with those of other chromatographic and immunological methods.

The use of radioreceptor assays for the determination of benzodiazepines in biological samples: a review.

Benzodiazepines are the most widely prescribed class of psychotropes. The demonstration of specific, high affinity binding sites for benzodiazepines in mammalian brain has provided a basis for a radioreceptor assay (RRA) of these compounds in biological samples (fluids or tissues). The RRA permits the simultaneous measurement of the benzodiazepine molecules that bind to the receptor, providing a total estimate of all pharmacologically active forms of the drug, which is useful in drug monitoring and in the intensive care of patients. After a complete description of the methodological aspects of this technique, the results obtained in therapeutic monitoring and in toxicological analysis are reviewed, and the advantages and disadvantages of this method are examined.