Routine antenatal ultrasound in low- and middle-income countries: first look - a cluster randomised trial.

OBJECTIVE: Ultrasound is widely regarded as an important adjunct to antenatal care (ANC) to guide practice and reduce perinatal mortality. We assessed the impact of ANC ultrasound use at health centres in resource-limited countries. DESIGN: Cluster randomised trial. SETTING: Clusters within five countries (Democratic Republic of Congo, Guatemala, Kenya, Pakistan, and Zambia) METHODS: Clusters were randomised to standard ANC or standard care plus two ultrasounds and referral for complications. The study trained providers in intervention clusters to perform basic obstetric ultrasounds. MAIN OUTCOME MEASURES: The primary outcome was a composite of maternal mortality, maternal near-miss mortality, stillbirth, and neonatal mortality. RESULTS: During the 24-month trial, 28 intervention and 28 control clusters had 24 263 and 23 160 births, respectively; 78% in the intervention clusters received at least one study ultrasound; 60% received two. The prevalence of conditions noted including twins, placenta previa, and abnormal lie was within expected ranges. 9% were referred for an ultrasound-diagnosed condition, and 71% attended the referral. The ANC (RR 1.0 95% CI 1.00, 1.01) and hospital delivery rates for complicated pregnancies (RR 1.03 95% CI 0.89, 1.20) did not differ between intervention and control clusters nor did the composite outcome (RR 1.09 95% CI 0.97, 1.23) or its individual components. CONCLUSIONS: Despite availability of ultrasound at ANC in the intervention clusters, neither ANC nor hospital delivery for complicated pregnancies increased. The composite outcome and the individual components were not reduced. TWEETABLE ABSTRACT: Antenatal care ultrasound did not improve a composite outcome that included maternal, fetal, and neonatal mortality.

Exogenous tannase improves feeding value of a diet containing field beans (Vicia faba) when fed to broilers.

A total of 72 male Ross 308 broilers were used in a study to investigate the effect of dietary tannase on apparent metabolisable energy (AME), coefficients of dry matter retention (DMR) and nitrogen retention (NR) and fat digestibility (FD) of a diet containing 300 g/kg field beans (Vicia faba). Growth performance variables and gastrointestinal tract development were also measured. Two treatments were used in this study: control (C) and C + 3400 tannase units (TU) per kg feed. Diets were formulated to be nutritionally adequate with the exception that the AME was lower than recommended (12.65 vs 12.97 MJ/kg, respectively). Inclusion of tannase increased AME by 0.4 MJ/kg DM. Tannase supplementation improved dietary DMR, NR and FD by 2.8%, 3.2% and 6.5%, respectively. Birds given tannase had 4.4% reduction in feed intake and 2.6% improvement in gain to feed ratio (P < 0.05). Compared to control diet, birds given tannase had reduced relative to body weight (%BW) proventriculus and gizzard and pancreas weights, 3.29% vs 3.09% and 0.47% vs 0.44%, respectively. The mechanisms of action of the studied enzyme require further elucidation.

A multiple imputation method for sensitivity analyses of time-to-event data with possibly informative censoring.

This article presents a multiple imputation method for sensitivity analyses of time-to-event data with possibly informative censoring. The imputed time for censored values is drawn from the failure time distribution conditional on the time of follow-up discontinuation. A variety of specifications regarding the post-discontinuation tendency of having events can be incorporated in the imputation through a hazard ratio parameter for discontinuation versus continuation of follow-up. Multiple-imputed data sets are analyzed with the primary analysis method, and the results are then combined using the methods of Rubin. An illustrative example is provided.

Specialty choices of medical students and house officers in Karachi, Pakistan.

Unerstanding patterns of career choices inmedicine is importnat for educators and policy-makers to plan the supply of specialists. This study analysed the career choices made by medical students and house officers in 2 private and 2 public medical schools in Karachi, Pakistan. An anonymous, self-administered and gynaecology were the 4 highest ranked specialties, with internal medicine ranked top as both the 1st and 2nd choice. Internal medicine was the 1st choice for significantly more students in public than private medical colleges (22.2% versus 1l4.9%). Students from private medical institutions chose a wider range of specialties than those from publicly-funded colleges. A high proportion of medical students and graduates in Karachi favour the same medical specialties, which may lead to saturation in those areas of specialization.

Enterococcus cecorum aortic valve endocarditis.

We report a case of human aortic valve infective endocarditis caused by Enterococcus cecorum. The organism was recovered from blood and identified by 16S ribosomal gene polymerase chain reaction (PCR). To the best of our knowledge, this is the first documented case of E. cecorum endocarditis. We wish to highlight the use of PCR for organism identification and to describe the initial misidentification of the pathogen.

Specialty choices of medical students and house officers in Karachi, Pakistan

Understanding patterns of career choices in medicine is important for educators and policy-makers to plan the supply of specialists. This study analysed the career choices made by medical students and house officers in 2 private and 2 public medical schools in Karachi, Pakistan. An anonymous, self-administered questionnaire was completed by 850 students. Internal medicine, paediatrics, general surgery and obstetrics and gynaecology were the 4 highest ranked specialties, with internal medicine ranked top as both the 1st and 2nd choice. Internal medicine was the 1st choice for significantly more students in public than private medical colleges [22.2% versus 14.9%]. Students from private medical institutions chose a wider range of specialties than those from publicly-funded colleges. A high proportion of medical students and graduates in Karachi favour the same medical specialties, which may lead to saturation in those areas of specialization

Analysis of longitudinal binary data with missing data due to dropouts.

Longitudinal binary data from clinical trials with missing observations are frequently analyzed by using the Last Observation Carry Forward (LOCF) method for imputing missing values at a visit (e.g., the prospectively defined primary visit time point for analysis at the end of treatment period). Usually, to understand time trend in treatment response, analyses are also performed separately on data at intermediate time points. The objective of such analyses is to estimate the proportion of "response" at a time point and then to compare two treatment groups (e.g., drug vs. placebo) by testing for the difference in the two proportions of response. The commonly used methods are Fisher's exact test, chi-squared test, Cochran-Mantel-Haenszel test, and logistic regression. Analyses based on the Observed Cases (OC) data are usually also performed and compared with those obtained by LOCF. Another approach that is gaining popularity (after the introduction of PROC GENMOD by the SAS Institute) is to use the method of Generalized Estimating Equations (GEE) with a view to include all repeated observations in the analysis in a more comprehensive manner. It is now well recognized, however, that results obtained by these methods are susceptible to bias, depending on the "missing data mechanism." Of particular concern is the bias introduced by NMAR dropouts. Because there is no one method to satisfactorily handle dropouts in data analysis, consensus is gathering toward doing analyses by several methods (including methods to handle NMAR dropouts) to evaluate sensitivity of results to model assumptions. In this article, we demonstrate application of the following methods for handling dropouts in longitudinal binary data: Generalized Linear Mixture Models (GLMM) (for handling NMAR dropouts), Weighted GEE (for handling MAR dropouts), and GEE (MCAR dropouts). The results are also compared with those obtained by logistic regression (univariate) on both LOCF and OC data.

Switching patients to aripiprazole from other antipsychotic agents: a multicenter randomized study.

RATIONALE: Switching patients from one antipsychotic to another can lead to tolerability problems or transient symptom exacerbations. It is important to compare switching strategies to determine which methods produce the best possible patient outcomes. OBJECTIVE: To investigate the efficacy, safety and tolerability of three dosing strategies for switching chronic, stable patients with schizophrenia from current oral antipsychotic monotherapy to once-daily oral aripiprazole monotherapy. METHOD: Patients in this 8-week, open-label, outpatient study were randomized to: 1). immediate initiation of 30 mg/day aripiprazole with simultaneous immediate discontinuation of current antipsychotic; 2). immediate initiation of 30 mg/day aripiprazole while tapering off current antipsychotic over 2 weeks; or 3). up-titrating aripiprazole to 30 mg/day over 2 weeks, while simultaneously tapering off current antipsychotic. Efficacy assessments included PANSS, CGI-S, and CGI-I scores. Safety assessments included: adverse events (AEs) recording, evaluation of extrapyramidal symptoms (EPS), vital signs, ECG, and clinical laboratory tests. RESULTS: Efficacy with aripiprazole was maintained during the study with numerical improvements compared with baseline in all three groups. The overall incidence of AEs was broadly comparable across all groups, and AEs were generally mild to moderate in severity and time-limited. Discontinuations due to AEs were comparable across the groups. No deterioration in EPS occurred in any group. The reduction in body weight and plasma prolactin levels following switch to aripiprazole were comparable across the three groups. CONCLUSION: Any of the three strategies evaluated can be used safely for switching patients to aripiprazole from antipsychotic monotherapy. Furthermore, patients' symptoms may continue to improve after switching to aripiprazole.

Efficacy and safety of aripiprazole and haloperidol versus placebo in patients with schizophrenia and schizoaffective disorder.

BACKGROUND: Aripiprazole is an investigational agent for treating schizophrenia that has a novel pharmacologic profile. The present study investigated the efficacy, safety, and tolerability of aripiprazole and haloperidol compared with placebo. METHOD: A 4-week, double-blind, randomized study, conducted at 36 U.S. centers between July 1997 and June 1998, compared aripiprazole (15 mg/day, 30 mg/day) to placebo, with haloperidol (10 mg/day) as an active control. Fixed doses of each agent were administered from day 1 throughout the study. A total of 414 patients with a primary DSM-IV diagnosis of schizophrenia or schizoaffective disorder were randomized. Efficacy measures included the Positive and Negative Syndrome Scale (PANSS) total, PANSS positive, PANSS negative, PANSS-derived Brief Psychiatric Rating Scale (BPRS) core, Clinical Global Impressions (CGI)-Severity of Illness, and mean CGI-Improvement scores. Safety and tolerability evaluations included extrapyramidal symptoms (EPS), weight gain, serum prolactin level, and QTc interval. RESULTS: Both doses of aripiprazole and haloperidol, 10 mg, produced statistically significant (p < or = .05) improvements from baseline in PANSS total, PANSS positive, PANSS-derived BPRS core, and CGI-Severity scores and significantly lower CGI-Improvement scores at endpoint, compared with placebo. Aripiprazole, 15 mg, and haloperidol, 10 mg, significantly improved PANSS negative score compared with placebo. Both aripiprazole doses and haloperidol separated from placebo for PANSS total scores at week 2. Unlike haloperidol, aripiprazole was not associated with significant EPS or prolactin elevation at endpoint compared with placebo. There were no statistically significant differences in mean changes in body weight across the treatment groups versus placebo, and no patients receiving aripiprazole experienced clinically significant increases in QTc interval. CONCLUSION: Aripiprazole, effective against positive and negative symptoms, is a safe and well-tolerated potential treatment for schizophrenia and schizoaffective disorder.

Weight change associated with valproate and lamotrigine monotherapy in patients with epilepsy.

OBJECTIVE: To compare the incidence and magnitude of change in body weight associated with lamotrigine or divalproex sodium monotherapy in patients with epilepsy. METHODS: A randomized, double-blind study with 8-week escalation phase and 24-week maintenance phase was conducted. Target maintenance dosage was 200 mg/day (lamotrigine) and 20 mg/kg/day (valproic acid), with adjustment from 100 to 500 mg/day (lamotrigine) and 10 to 60 mg/kg/day (valproate) based on investigators' judgment. Eligible patients were > or = 12 years old with new-onset or previously diagnosed partial or generalized seizures. Weight change was primary and seizure frequency and tolerance were secondary outcome measures. RESULTS: For the lamotrigine group, 65 patients (mean age 34.5 years) were investigated; for the valproate group, 68 patients (mean age 30.1 years) were investigated. Weight remained stable in lamotrigine-treated patients. Significant weight gain occurred in valproate-treated patients by the 10th week of treatment; weight continued to increase throughout the study. After 32 weeks of treatment, mean weight gain was significantly higher in valproate-treated (12.8 +/- 9.3 lb) than lamotrigine-treated (1.3 +/- 11.9 lb) patients. Similar proportions of patients in lamotrigine (29%) and valproate (26%) groups were seizure-free. Overall frequency of adverse events was similar between the two treatment groups. Mean time to withdrawal from the study due to adverse events was 103 +/- 70 days for the lamotrigine group and 79 +/- 48 days for the valproate group. CONCLUSION: Valproate monotherapy was associated with significantly greater weight gain than lamotrigine monotherapy. Weight gain associated with valproate was significant within 10 weeks after initiating therapy and continued throughout the study. Efficacy of lamotrigine was comparable with that of valproate; lamotrigine tended to be better tolerated.

Six-month evaluation of Carbatrol (extended-release carbamazepine) in complex partial seizures.

We evaluated the use of a new, controlled-release capsule form of carbamazepine, Carbatrol capsules, in an open-label, multicenter study of 124 patients with complex partial seizures. Ninety-one percent of the patients successfully completed the 6-month trial with good seizure control, with a significant improvement in quality of life. We conclude that switching patients with complex partial seizures from multiple daily-dose carbamazepine to twice-daily Carbatrol on a milligram-to-milligram basis is relatively safe.

Contributions of GABAA receptors and GABAC receptors to acetylcholine release and directional selectivity in the rabbit retina.

GABA is a major inhibitory neurotransmitter in the mammalian retina and it acts at many different sites via a variety of postsynaptic receptors. These include GABAA receptors and bicuculline-resistant GABAC receptors. The release of acetylcholine (ACh) is inhibited by GABA and strongly potentiated by GABA antagonists. In addition, GABA appears to mediate the null inhibition which is responsible for the mechanism of directional selectivity in certain ganglion cells. We have used these two well-known examples of GABA inhibition to compare three GABA antagonists and assess the contributions of GABAA and GABAC receptors. All three GABA antagonists stimulated ACh release by as much as ten-fold. By this measure, the ED50s for SR-95531, bicuculline, and picrotoxin were 0.8, 7.0, and 14 microM, respectively. Muscimol, a potent GABAA agonist, blocked the effects of SR-95531 and bicuculline, but not picrotoxin. This indicates that SR-95531 and bicuculline are competitive antagonists at the GABAA receptor, while picrotoxin blocks GABAA responses by acting at a different, nonreceptor site such as the chloride channel. In the presence of a saturating dose of SR-95531 to completely block GABAA receptors, picrotoxin caused a further increase in the release of ACh. This indicates that picrotoxin potentiates ACh release by a mechanism in addition to the block of GABAA responses, possibly by also blocking GABAC receptors, which have been associated with bipolar cells. All three GABA antagonists abolished directionally selective responses from ON/OFF directional-selective (DS) ganglion cells. In this system, the ED50S for SR-95531, bicuculline, and picrotoxin were 0.7 microM, 8 microM, and 94.6 microM, respectively. The results with SR-95531 and bicuculline indicate that GABAA receptors mediate the inhibition responsible for directional selectivity. The addition of picrotoxin to a high dose of SR-95531 caused no further increase in firing rate. The comparatively high dose required for picrotoxin also suggests that GABAC receptors do not contribute to directional selectivity. This in turn suggests that feedforward GABAA inhibition, as opposed to feedback at bipolar terminals, is responsible for the null inhibition underlying directional selectivity.

Drug-induced seizures in the elderly. Causative agents and optimal management.

We conducted a review of drugs that were most commonly associated with inducing seizures in the elderly population. The method for determining the risk of these agents includes evaluating the utilisation and the percentage of adverse events in previous studies and case reports. Classes of medications, such as anti-psychotics and antidepressants, are extensively reviewed to provide the clinician with treatment options in high risk patients. The risk of seizures secondary to the withdrawal of alcohol (ethanol) and benzodiazepines, and methods employed to minimise the risk are discussed. In addition, the management of patients with drug-induced seizures is delineated. Drug-induced seizures are a potentially serious adverse effect. It is important that clinicians are aware of which classes of medications and individual medications are associated with reducing seizure threshold.

Vagus nerve stimulation for treatment of partial seizures: 1. A controlled study of effect on seizures. First International Vagus Nerve Stimulation Study Group.

Vagus nerve stimulation (VNS) was shown to reduce seizure frequency in refractory epilepsy patients in two pilot studies. Based on these results, a multicenter, prospectively randomized, parallel, double-blind study of patients with refractory partial seizures was initiated. After a 12-week baseline period, identical vagus nerve stimulators were implanted and patients randomized to either a high or low 14-week VNS treatment paradigm. The primary objective was to demonstrate that high VNS (therapeutic parameters) was more effective in reducing partial seizure frequency than was low VNS (less or noneffective parameters). Patients continued receiving antiepileptic drugs (AEDs) with plasma concentrations held constant throughout the study. We report results of the first 67 patients to exit the 14-week acute phase. After 14 weeks of VNS, 31 patients receiving high VNS experienced a mean seizure frequency percentage reduction of 30.9%, which was statistically significant as compared with the mean seizure frequency percentage reduction of 11.3% in 36 patients receiving low VNS (p = 0.029, t test; p = 0.036, Wilcoxon rank-sum test). In addition to the significant intragroup p-values, mean seizure frequency percentage change reached statistical significance for high VNS (p < 0.001) but not low VNS (p = 0.072) as compared with baseline. Twelve of 31 (38.7%) patients receiving high VNS achieved at least 50% reduction in seizure frequency whereas 7 of 36 (19.4%) patients receiving low VNS experienced at least 50% reduction after 14 weeks. The implant procedure and VNS therapy were well tolerated. Our study confirmed the effectiveness of VNS as treatment for epilepsy patients with refractory partial seizures.

Valproate-associated pancreatitis.

To assess the clinical characteristics of valproate (VPA)-associated pancreatitis, information from three sources was gathered: (a) a survey among 507 physicians with a special interest in treatment of epilepsy, (b) a review of the authors' patient population, and (c) a review of the literature. Of 366 physicians answering the survey, 53 (14.5%) reported a case of pancreatitis. Thirty-nine cases were available for review (24 from the medical literature, 12 from the survey, and 3 from the authors). Pancreatitis appeared to be more frequent in young persons (mean age 16.4 years) but may occur at any age. The highest risk appears to exist during the first months of treatment: 43.8% of the cases developed during the first 3 months, and 68.8% developed during the first year. Seventy-six percent of patients were receiving polytherapy, and 41% had some form of associated chronic encephalopathy. In most patients, the reaction was rapidly reversible when VPA was discontinued. It was severe in 6 patients, with 3 deaths reported. Rechallenge with VPA was attempted in 9 patients, with a high incidence of relapses. Asymptomatic elevation of serum amylase in patients receiving VPA was reported by 40 (10.9%) of the physicians surveyed. Awareness of the problem and early discontinuation of VPA may be effective in preventing serious reactions.

MR imaging in chronic partial epilepsy: role of contrast enhancement.

Gadopentetate dimeglumine was administered prospectively to 150 consecutive patients who had had partial epilepsy for longer than 1 year to determine whether it is routinely indicated for the diagnosis of this disorder. MR abnormalities correlating with clinical or electroencephalographically documented seizure foci were detected in 69 cases (46%). Contrast enhancement was seen in 33 of these lesions, but the presence of enhancement altered the original radiologic diagnosis in only 17 (11%) of 150 cases. In only two cases (1%) did contrast administration reveal lesions that were not definitely apparent on the unenhanced images. The utility of contrast administration could not be predicted on the basis of seizure type (simple or complex) or the presence of secondary generalization. Gadopentetate dimeglumine does not appear to be routinely required in the MR workup of patients with chronic partial epilepsy. It should be used selectively to clarify or better define the nature of abnormalities encountered on unenhanced images.

Epidemiology of acute respiratory tract infections among young children in Kenya.

The epidemiology of acute respiratory tract infection (ARI) was investigated in a rural community 80 km north of Nairobi, Kenya. This research was conducted prospectively on 250 families with 470 children less than 5 years of age who were contacted every 8 days during the 3-year study. The yearly incidence of respiratory tract infections decreased from 5.2 to 3.4 during the study; less than 5% of these infections involved the lower respiratory tract. The incidence was inversely related to age, and the illnesses were generally mild and brief in length. Fifteen children died during the study period. The precise causes of death are unknown, but respiratory infections possibly played a role in most cases. This study emphasizes the importance of determining the risk factors responsible for unusually severe morbidity and high mortality in children with ARI in developing countries.

Catastrophic neurologic signs due to drug interaction: Tegretol and Darvon.

Eight cases of carbamazepine toxicity from interaction with propoxyphene are reported. Serum concentrations of carbamazepine increased up to sixfold. All patients were symptomatic and two were hospitalized. Practitioners prescribing propoxyphene acutely for pain should be aware of this significant interaction.