Efficacy and safety of intravenous lacosamide in refractory nonconvulsive status epilepticus

BACKGROUND

Lacosamide (LCM) is a novel antiepileptic drug (AED) recently approved as an adjunctive therapy in the treatment of partial seizures in adults. LCM is available in oral and intravenous formulations, has linear pharmacokinetics and a unique mechanism of action.

THE AIM OF THIS STUDY

To evaluate the safety and efficacy of intravenous LCM in the treatment of nonconvulsive status epilepticus (NCSE) after failure of conventional therapy.

METHODS

We retrospectively reviewed all patients with NCSE treated with LCM. We reviewed the clinical and electrographic changes before and after LCM administration. We also noted any reported side effects including electrocardiographic changes.

RESULTS

We report four cases of NCSE that were refractory to conventional treatment, but readily responsive to LCM. No side effects attributable to LCM were identified.

CONCLUSIONS

Intravenous LCM may be safe and efficacious as an add-on AED for the treatment of NCSE when standard therapy fails.

Risk factors for secondary proctectomy in patients with familial adenomatous polyposis

Background

Colectomy and ileorectal anastomosis (IRA) or restorative proctocolectomy are performed for prophylaxis in familial adenomatous polyposis (FAP). After IRA patients may require secondary proctectomy for worsening polyposis or rectal cancer. Outcomes after IRA were evaluated and risk factors predictive of progressive rectal disease identified.

Methods

Parametric survival analysis was used to identify predictors of progressive rectal disease in all patients undergoing an IRA for FAP at a single centre. Hazard ratios (HRs) were calculated for phenotype, genotype, sex, age at surgery and presence of colonic cancer.

Results

Of 427 patients who underwent IRA, 48 (11·2 per cent) developed rectal cancer and 77 (18·0 per cent) required proctectomy for worsening polyposis over a median follow-up of 15 (range 7–25) years. By the age of 60 years half of the patients retained their rectum. Rectal polyp count exceeding 20 (HR 30·99, 95 per cent confidence interval 9·57 to 100·32; P < 0·001), APC mutation codon 1250–1450 (HR 3·91, 1·45 to 10·51; P = 0·007), colonic polyp count 500 or more (HR 2·18, 1·24 to 3·82; P = 0·006) and age less than 25 years at the time of surgery (HR 1·99, 1·17 to 3·37; P = 0·011) were independent predictors of progressive rectal disease.

Conclusion

The risk of proctectomy after IRA for FAP is based on patient genotype, phenotype and age at surgery.

Electrocorticographic frequency alteration mapping of speech cortex during an awake craniotomy: case report

OBJECTIVE

Traditional electrocortical stimulation (ECS) mapping is limited by the lengthy serial investigation (one location at a time) and the risk of afterdischarges in localizing eloquent cortex. Electrocorticographic frequency alteration mapping (EFAM) allows the parallel investigation of many cortical sites in much less time and with no risk of afterdischarges because of its passive nature. We examined its use with ECS in the context of language mapping during an awake craniotomy for a tumor resection.

CLINICAL PRESENTATION

The patient was a 61-year-old right-handed Caucasian male who presented with headache and mild aphasia. Imaging demonstrated a 3-cm cystic mass in the posterior temporal-parietal lobe. The patient underwent an awake craniotomy for the mapping of his speech cortex and resection of the mass.

INTERVENTION

Using a 32-contact electrode array, electrocorticographic signals were recorded from the exposed cortex as the patient participated in a 3-min screening task involving active (patient naming visually presented words) and rest (patient silent) conditions. A spectral comparison of the 2 conditions revealed specific cortical locations associated with activation during speech. The patient was then widely mapped using ECS. Three of 4 sites identified by ECS were also identified passively and in parallel by EFAM, 2 with statistical significance and the third by qualitative inspection.

CONCLUSION

EFAM was technically achieved in an awake craniotomy patient and had good concordance with ECS mapping. Because it poses no risk of afterdischarges and offers substantial time savings, EFAM holds promise for future development as an adjunct intraoperative mapping tool. Additionally, the cortical signals obtained by this modality can be utilized for localization in the presence of a tumor adjacent to the eloquent regions.

Ventricular dilation and elevated aqueductal pulsations in a new experimental model of communicating hydrocephalus

In communicating hydrocephalus (CH), explanations for the symptoms and clear-cut effective treatments remain elusive. Pulsatile flow through the cerebral aqueduct is often significantly elevated, but a clear link between abnormal pulsations and ventriculomegaly has yet to be identified. We sought to demonstrate measurement of pulsatile aqueductal flow of CSF in the rat, and to characterize the temporal changes in CSF pulsations in a new model of CH. Hydrocephalus was induced by injection of kaolin into the basal cisterns of adult rats (n = 18). Ventricular volume and aqueductal pulsations were measured on a 9.4 T MRI over a one month period. Half of the animals developed ventricular dilation, with increased ventricular volume and pulsations as early as one day post-induction, and marked chronic elevations compared to intact controls (volume: 130.15 +/- 83.21 microl vs. 15.52 +/- 2.00 microl; pulsations: 114.51 nl +/- 106.29 vs. 0.72 +/- 0.13 nl). Similar to the clinical presentation, the relationship between ventricular size and pulsations was quite variable. However, the pulsation time-course revealed two distinct sub-types of hydrocephalic animals: those with markedly elevated pulsations which persisted over time, and those with mildly elevated pulsations which returned to near normal levels after one week. These groups were associated with severe and mild ventriculomegaly respectively. Thus, aqueductal flow can be measured in the rat using high-field MRI and basal cistern-induced CH is associated with an immediate change in CSF pulsatility. At the same time, our results highlight the complex nature of aqueductal pulsation and its relationship to ventricular dilation.

Residents' perceptions of work environment during their postgraduate medical training in Pakistan

BACKGROUND

In Pakistan, there is a lack of information about the work environment of residency programs. This lack is a major impediment in their improvement. One of the approaches for improvement in these programs can be directed through the residents' own perception of their working conditions. Therefore, we collected data which would reflect working conditions of residents.

AIM

To assess the perceived status of "work environment" in different specialities.

MATERIALS AND METHODS

A cross-sectional survey was conducted in four teaching hospitals of Karachi from July 1999 to January 2000. Residents from selected programs were grouped into four broad groups: specialist, medical, surgical and multidisciplinary. Responses of residents were obtained on a Likert scale of 0 to 4. Indices were formed for two components of work environment: academic and mistreatment.

STATISTICAL ANALYSIS

Differences between residents' groups were assessed through analysis of variance (ANOVA) at 5% significance.

RESULTS

A total of 341 registered residents responded (response rate: 75%). Surgical residents were working more than 80 h/week and this was more than the other three groups. Medical residents were spending the highest actual time on research and teaching activities (10% and 14%, respectively). Academic index score was highest for surgical group (15.81, SD = 4.69) and lowest for multidisciplinary group (11.82, SD = 4.80). Medical group had the highest perceived mistreatment index score (5.56, SD = 4.57).

CONCLUSIONS

In a study of work environment of residency programs, differential impact was found for the four groups on work environment perceptions. Most of the residents recognized undergraduate teaching, grand rounds, patient rounds and seminars or workshops as contributing to their academic learning. Reporting of sexual harassment was low, indicating either underreporting or cultural dynamics of our setting.

Evaluation of Roche Diagnostics ONLINE(R) DAT II, a New Generation of Assays for the Detection of Drugs of Abuse

A new generation of ONLINE assays has been developed that offers improved performance and enhanced ease of use. This family of assays is being applied to both the COBAS INTEGRA and Roche/Hitachi line of analyzers. The four ONLINE DAT II assays that were evaluated included cocaine (benzoylecgonine) (BE), methadone (MDN), opiates (OP), and tetrahydrocannabinol (THC). The BE assay has a dual cutoff (150/300 ng/mL) with a dynamic range from 0 to 5000 ng/mL. The MDN assay has a cutoff of 300 ng/mL with a dynamic range from 0 to 2000 ng/mL. The opiates assay has a 300 ng/mL cutoff with a 0 to 2000 ng/mL range and a 2000 ng/mL cutoff with a 0 to 8000 ng/mL range. The THC assay has 20, 50, and 100 ng/mL cutoffs with 0 to 100, 0 to 300, and 0 to 300 ng/mL dynamic ranges, respectively. The ranges of the intra-assay precision (coefficients of variation for n = 20) run in the semiquantitative mode are 2.3-7.5% for BE, 2.0-3.8% for MDN, 1.9-4.2% for OP, and 3.9-5.2% for THC. The intra-assay qualitative precision for all of the assays as calculated from absorbance values is generally higher than that of the intra-assay semiquantitative precision at the cutoff. The qualitative precision ranges between 0.4% and 3.1%. The standard curve stability defined for the COBAS INTEGRA systems for these reagents ranges from 35 to 68 days. The clinical sensitivity and specificity were compared to the OnLine generation I and CEDIA immunoassays, as well as gas chromatography-mass spectrometry (GC-MS). The results indicate that for each assay, the sensitivity and specificity were the same or greater when compared to the other two immunoassay technologies. The results of each assay also correlated very well (> 99%) when compared with GC-MS.

Seroprevalence of avian influenza virus and its relationship with increased mortality and decreased egg production

To evaluate the occurrence of avian influenza viruses (AIV) infections in southern Pakistan, an enzyme-linked immunosorbent assay was initially used to screen sera from broiler, layer and broiler breeder flocks for the presence of antibodies to type A influenza viruses. Data from this survey showed high levels of AIV antibodies, indicating unrecognized AIV infection occurring in these flocks. Based on this information a second investigation was undertaken in selected broiler-breeder, broiler and layer flocks. In this investigation, nine H9N2 AIV isolates were recovered. Serological data from this investigation indicated that chickens in flocks with a previous history of respiratory tract infection and some without overt clinical respiratory signs had seroconverted to H9N2 AIV.

Characterisation of axon terminals in the rat dorsal horn that are immunoreactive for serotonin 5-HT3A receptor subunits

Serotonin 5-HT(3) receptors are abundant in the superficial dorsal horn and are likely to have an involvement in processing of nociceptive information. It has been shown previously that 5-HT(3) receptors are present on primary afferent terminals and some dorsal horn cells. The primary aim of the present study was to determine what classes of primary afferent possess 5-HT(3)A receptor subunits. We performed a series of double- and triple-labelling immunofluorescence experiments. Subunits were labelled with an anti-peptide antibody and primary afferent axons were identified by the presence of calcitonin gene-related peptide (CGRP) and binding of the lectin IB4. Quantitative confocal microscopic analysis revealed that approximately 10% of axons displaying 5-HT(3)A immunoreactivity were also labelled for CGRP but that only 3% of these fibres bind IB4. We also investigated the relationship between immunoreactivity for the subunit and descending serotoninergic systems, axons originating from inhibitory neurons that contain glutamic acid decarboxylase, and axons of a subpopulation of excitatory neurons that contain neurotensin. None of these types of axon was associated with immunoreactivity for receptor subunits. Ultrastructural studies confirmed that punctate immunoreactive structures observed with the light microscope were axon terminals. These terminals invariably formed asymmetric synaptic junctions with dendritic profiles and often contained a mixture of granular and agranular vesicles. Some terminals formed glomerular-like arrangements. Immunoreactive cells were also examined and were found to contain intense patches of reaction product within the cytoplasm. We conclude that the majority (about 87%) of dorsal horn axons that are immunoreactive for 5-HT(3)A receptor subunits do not originate from the subtypes of primary afferent fibres that bind IB4 or contain CGRP. It is likely that most of these axons have an excitatory action and they may originate from dorsal horn interneurons and/or fine myelinated primary afferent fibres.

Spatial learning deficits without hippocampal neuronal loss in a model of early-onset epilepsy

Studies were undertaken to examine the effects recurrent early-life seizures have on the ability of rats to acquire spatial memories in adulthood. A minute quantity of tetanus toxin was injected unilaterally into the hippocampus on postnatal day 10. Within 48 h, rats developed recurrent seizures that persisted for 1 week. Between postnatal days 57 and 61, rats were trained in a Morris water maze. Toxin-injected rats were markedly deficient in learning this task. While these rats showed gradual improvement in escape latencies over 20 trials, their performance always lagged behind that of controls. Poor performance could not be explained by motor impairments or motivational difficulties since swimming speed was similar for the groups. Only eight of 16 toxin-injected animals showed focal interictal spikes in the hippocampus during electroencephalographic recordings. This suggests that learning deficiencies and chronic epilepsy may be independent products of recurrent early-life seizures. A quantitative analysis of hippocampus revealed a significant decrease in neuronal density in stratum pyramidale of experimental rats. However, the differences were largely explained by a concomitant increase in the area of stratum pyramidale. Studies of glial fibrillary acidic protein expression and spread of horseradish peroxidase-conjugated tetanus toxin in the hippocampus suggest that the dispersion of cell bodies in stratum pyramidale can neither be explained by a reactive gliosis nor the direct action of the toxin itself. Taken together, we suggest that recurrent seizures beginning in early life can lead to a significant deficiency in spatial learning without ongoing hippocampal synchronized network discharging or a substantial loss of hippocampal pyramidal cells.

Comparison of clinical and laparascopic features of infertile women suffering from genital tuberculosis (TB) or pelvic inflammatory disease (PID) or endometriosis

OBJECTIVE

The objective of the study was to analyze the clinical and laparoscopic features, which may help to differentiate between infertility in females due to Genital Tuberculosis from Pelvic Inflammatory Disease (PID) and Endometriosis.

METHODS

This case control study was carried out in a teaching tertiary care hospital. Medical records were searched from 1st January 1987 to 31st December 2000 and 43 infertile women with biopsy proven genital tract tuberculosis were found. Equal number of infertile females with diagnosed PID and Endometriosis were randomly selected. Comparisons were done between features of Genital Tuberculosis with PID and Endometriosis separately and also genital tuberculosis with combined controls of PID and Endometriosis.

RESULTS

Patients with genital tuberculosis commonly had primary infertility. PID and Endometriosis patients had early menarche and increased duration of menstruation. On physical examination, patients with Genital Tuberculosis were found to have short heights. No significant findings were observes in the pelvic examination and menstruation history between the comparison groups. Laparascopic examination revealed that fallopian tubes were abnormal, tortuous, bilaterally blocked and thickly adherent more commonly in Genital Tuberculosis when compared to other groups.

CONCLUSION

The primary infertility patients with chronic malnutrition and massive adhesive fallopian tubes on laproscopic examination should be evaluated for genital tuberculosis.

Wortmannin inhibits platelet aggregation produced by interaction of gamma-aminobutyric acid and the calcium tonophore, A23187

Platelet aggregation by gamma-aminobutyric acid (GABA) agonists combined with a calcium ionophore was studied. GABA, baclofen and mucimol markedly amplified aggregatory responses to a subthreshold concentration of the ionophore, A23187. This effect was inhibited by wortmannin, a blocker of phosphoinositide 3-kinase. However, several antagonists of GABA receptors had no effect on the response, and benzodiazepines inhibited aggregation. These results suggest that the GABA effect is not mediated by traditional neuronal GABA receptors. We propose that wortmannin inhibits aggregation at a nexus downstream from membrane mechanisms triggered by the GABA-A23187 interaction.

History, development and clinical success of porcelain inlays

The drive for alternative to amalgam as a restorative material is led by concerns about the safety of mercury within amalgam and also by aesthetic demands from patients. Early attempts to address these issues produced disappointing results in terms of performance from directly-placed resin composites in posterior teeth. While directly-placed posterior restorative materials have improved in recent years the indirect constructed inlay may more readily meet the functional requirements of premolar/molar teeth. This article seeks to review the history, development and clinical success of porcelain when used as an inlay material. A case is included to demonstrate the clinical application of this aesthetic technique and the author's personal recommendations.