Review: Treatment of early multiple sclerosis: the value of treatment initiation after a first clinical episode

Multiple sclerosis is a chronic, demyelinating disorder of the central nervous system. It is characterised by progressive neurological disability, which is likely to occur as a result of permanent axonal damage. Such damage may be reflected by brain atrophy, which can be identified early in the course of the disease. Patients who present with an initial episode of inflammatory demyelination, commonly referred to as a clinically isolated syndrome, are at high risk of developing clinically definite multiple sclerosis, especially if their magnetic resonance imaging studies suggest the presence of multi-focal disease. Treatment with disease-modifying therapies at the initial episode of demyelination may postpone this development. In this review we present an overview of evidence supporting early treatment initiation. We focus on three large placebo-controlled trials of interferon beta therapy: Controlled High-Risk Avonex® Multiple Sclerosis Prevention Study, Early Treatment of Multiple Sclerosis and Betaferon ® in Newly Emerging Multiple Sclerosis for Initial Treatment. Results from these early treatment studies are presented, and the impact of using interferon beta treatment in the early stages of disease is discussed with the aim of considering optimal therapeutic strategies to improve long-term patient outcome.

Alemtuzumab

When the CAMMS 223 trial was formally reported in the New England Journal of Medicine in October of 2008, huge interest was generated in the media, among people with multiple sclerosis (MS) and their relatives and friends. The suggestion that a therapy Campath-1H (now known as alemtuzumab) was available which surpassed the effectiveness of current standard treatments, provided by infusions given at yearly intervals or even less frequently and which appeared to reduce the accumulation of disability was hailed in the lay press as virtually a 'cure'. The paper in this edition of the journal (Spotlight on Alemtuzumab, page 77) provides a more realistic account of alemtuzumab, describing the Cambridge experience, tracking the history of Campath-1H, one of the oldest humanized monoclonal antibodies, from its origin in the laboratory to its future licensing in the clinical management of people with MS.

Mutations in 3 genes (MKS3, CC2D2A and RPGRIP1L) cause COACH syndrome (Joubert syndrome with congenital hepatic fibrosis)

OBJECTIVE

To identify genetic causes of COACH syndrome

BACKGROUND

COACH syndrome is a rare autosomal recessive disorder characterised by Cerebellar vermis hypoplasia, Oligophrenia (developmental delay/mental retardation), Ataxia, Coloboma, and Hepatic fibrosis. The vermis hypoplasia falls in a spectrum of mid-hindbrain malformation called the molar tooth sign (MTS), making COACH a Joubert syndrome related disorder (JSRD).

METHODS

In a cohort of 251 families with JSRD, 26 subjects in 23 families met criteria for COACH syndrome, defined as JSRD plus clinically apparent liver disease. Diagnostic criteria for JSRD were clinical findings (intellectual impairment, hypotonia, ataxia) plus supportive brain imaging findings (MTS or cerebellar vermis hypoplasia). MKS3/TMEM67 was sequenced in all subjects for whom DNA was available. In COACH subjects without MKS3 mutations, CC2D2A, RPGRIP1L and CEP290 were also sequenced.

RESULTS

19/23 families (83%) with COACH syndrome carried MKS3 mutations, compared to 2/209 (1%) with JSRD but no liver disease. Two other families with COACH carried CC2D2A mutations, one family carried RPGRIP1L mutations, and one lacked mutations in MKS3, CC2D2A, RPGRIP1L and CEP290. Liver biopsies from three subjects, each with mutations in one of the three genes, revealed changes within the congenital hepatic fibrosis/ductal plate malformation spectrum. In JSRD with and without liver disease, MKS3 mutations account for 21/232 families (9%).

CONCLUSIONS

Mutations in MKS3 are responsible for the majority of COACH syndrome, with minor contributions from CC2D2A and RPGRIP1L; therefore, MKS3 should be the first gene tested in patients with JSRD plus liver disease and/or coloboma, followed by CC2D2A and RPGRIP1L.

Clinical experience with argatroban for heparin-induced thrombocytopenia in a large teaching hospital

BACKGROUND

Argatroban is a direct thrombin inhibitor approved for the prophylaxis or treatment of thrombosis in patients with heparin-induced thrombocytopenia (HIT). The product monograph does not guide clinicians beyond specifying the initial dose of 2 μg/kg per minute (or 0.5 μg/kg per minute for patients with hepatic impairment). Some authors have suggested that in the intensive care unit (ICU) and for patients with acute cardiac disease and those with renal or hepatic dysfunction, this dose may result in a supratherapeutic activated partial thromboplastin time (aPTT).

OBJECTIVES

To evaluate the efficacy and safety of argatroban in adult patients with suspected HIT in a large teaching hospital, and to review dosing for patients in the ICU, patients with acute cardiac disease, and patients with renal or hepatic dysfunction.

METHODS

Charts of patients with suspected HIT who had received argatroban for at least 24 h between October 1, 2005, and October 1, 2007, at the Foothills Medical Centre, Calgary, Alberta, were examined retrospectively.

RESULTS

Thirty patients met the inclusion criteria, with charts available for review. Of these, 21 (70%) patients had an initial argatroban dose of 2 μg/kg per minute and 4 (13%) had an initial dose of 0.5 μg/kg per minute. The median duration of therapy was 6 days, and the mean dose was 2.14 μg/kg per minute. There were 122 dosage adjustments, the most common change being 0.5 μg/kg per minute, followed by adjustments of 1 and 0.1 μg/kg per minute. Six patients had supratherapeutic aPTT values (above 100 s), and none experienced major bleeding.

CONCLUSIONS

The results of this study suggest that an initial argatroban dose of 2 μg/kg per minute is appropriate for patients with no hepatic dysfunction. Patients with acute cardiac disease and critically ill patients may require lower doses of argatroban; however no dosage adjustments are required for patients with renal dysfunction.

Assessment of Poisson, logit, and linear models for genetic analysis of clinical mastitis in Norwegian Red cows

Clinical mastitis is typically coded as presence/absence during some period of exposure, and records are analyzed with linear or binary data models. Because presence includes cows with multiple episodes, there is loss of information when a count is treated as a binary response. The Poisson model is designed for counting random variables, and although it is used extensively in epidemiology of mastitis, it has rarely been used for studying the genetics of mastitis. Many models have been proposed for genetic analysis of mastitis, but they have not been formally compared. The main goal of this study was to compare linear (Gaussian), Bernoulli (with logit link), and Poisson models for the purpose of genetic evaluation of sires for mastitis in dairy cattle. The response variables were clinical mastitis (CM; 0, 1) and number of CM cases (NCM; 0, 1, 2, ..). Data consisted of records on 36,178 first-lactation daughters of 245 Norwegian Red sires distributed over 5,286 herds. Predictive ability of models was assessed via a 3-fold cross-validation using mean squared error of prediction (MSEP) as the end-point. Between-sire variance estimates for NCM were 0.065 in Poisson and 0.007 in the linear model. For CM the between-sire variance was 0.093 in logit and 0.003 in the linear model. The ratio between herd and sire variances for the models with NCM response was 4.6 and 3.5 for Poisson and linear, respectively, and for model for CM was 3.7 in both logit and linear models. The MSEP for all cows was similar. However, within healthy animals, MSEP was 0.085 (Poisson), 0.090 (linear for NCM), 0.053 (logit), and 0.056 (linear for CM). For mastitic animals the MSEP values were 1.206 (Poisson), 1.185 (linear for NCM response), 1.333 (logit), and 1.319 (linear for CM response). The models for count variables had a better performance when predicting diseased animals and also had a similar performance between them. Logit and linear models for CM had better predictive ability for healthy cows and had a similar performance between them.

Inappropriate use of intravenous pantoprazole: extent of the problem and successful solutions

BACKGROUND & AIMS

Indications for intravenous proton pump inhibitors (IV PPI) include upper gastrointestinal bleeding (UGIB) from peptic ulcer disease with high-risk stigmata and patients receiving nothing by mouth (NPO). The objectives were to assess the extent of errors in indications for IV PPI use and to determine whether multidisciplinary interventions could improve IV PPI use and costs.

METHODS

Part 1: Patients prescribed IV PPI during a period of 4 months were divided into 2 settings, UGIB or non-UGIB. The setting-specific appropriateness of the IV PPI indication and dosing regimen was determined. Part 2: Patients prescribed IV PPI before and after multidisciplinary interventions (educating physicians, a computerized dose template, pharmacists altering IV PPI orders in non-UGIB patients who were not NPO, and recommending a GI consult when a continuous infusion was ordered) were studied. Incidence of prescribing errors, IV PPI costs, and potential confounders were compared.

RESULTS

Part 1: Only 50% of UGIB (n = 145) patients received IV PPI for an appropriate indication. Both indication and dosing regimen were appropriate in 21%. In the non-UGIB group (n = 95), 33% were truly NPO; 51% had a correct dosing frequency. Part 2: The postintervention (n = 105) group (vs the preintervention group, n = 113) showed a significant absolute reduction in the degree of inappropriate indication in the UGIB (26%; 95% confidence interval [CI], 10%-42%; P < .0001) and in the non-UGIB (41%; 95% CI, 24%-58%; P < .0001) subgroups. However, a greater improvement in underspending than overspending meant that overall costs were unchanged.

CONCLUSIONS

IV PPI was frequently prescribed inappropriately and incorrectly; simple maneuvers resulted in reductions in errors.

Treatment of stiff person syndrome with rituximab

This case report is about the novel use of the anti-CD20 antibody, rituximab, in the treatment of a 41 year old woman with stiff person syndrome. She was admitted to hospital as an emergency with prolonged and painful extensor spasms affecting the neck and back, arms, and legs. The disease had progressed despite a favourable initial response to conventional treatment with intravenous immunoglobulin and cytotoxics. Treatment with rituximab induced a lasting clinical remission.

Mitochondrial dysfunction plays a key role in progressive axonal loss in Multiple Sclerosis

Multiple Sclerosis is the most common inflammatory demyelinating disease of the central nervous system and is the leading cause of non traumatic neurological disability in young adults. In recent years it has become increasingly evident that axonal degeneration is a key player in the pathogenesis of disability in MS but the mechanisms that lead to axonal damage are not fully understood. It seems likely that the causes of axonal damage vary at different stages of the disease and several theories have evolved that address the mechanisms leading to axonal loss in the acute stages of demyelination. There has been relatively little attention given to investigation of the mechanisms involved in chronic axonal loss in the progressive stages of MS. We propose a hypothesis that mitochondria play a key role in this chronic axonal loss. Following demyelination there is redistribution of sodium channels along the axon and mitochondria are recruited to the demyelinated regions to meet the increased energy requirements necessary to maintain conduction. The mitochondria present within the chronically demyelinated axons will be functioning at full capacity. The axon may well be able to function for many years due to these adaptive mechanisms but we propose that eventually, despite antioxidant defences, free radical damage will accumulate and mitochondrial function will become compromised. ATP concentration within the axon will decrease and the effect on axonal function will be profound. The actual cause of cell death could be due to a number of mechanisms related to mitochondrial dysfunction including failure of ionic homeostasis, calcium influx, mitochondrial mediated cell death or impaired axonal transport. Whatever the cause of axonal loss our hypothesis is that mitochondria are central to this process. We explore steps to test this hypothesis and discuss the possible therapeutic approaches which target the mitochondrial mechanisms that may contribute to chronic axonal loss.

The distributions of mitochondria and sodium channels reflect the specific energy requirements and conduction properties of the human optic nerve head

AIM

To study the normal distributions of mitochondria and voltage gated Na+ channels in the human optic nerve head in order to gain insight into the potential mechanisms of optic nerve dysfunction seen in the inherited optic neuropathies.

METHODS

Five fresh frozen human optic nerves were studied. Longitudinally orientated, serial cryosections of optic nerve head were cut for mitochondrial enzyme histochemistry and immunolabelling for cytochrome c oxidase (COX) subunits and voltage gated Na+ channel subtypes (Na(v) 1.1, 1.2, 1.3, and 1.6).

RESULTS

A high density of voltage gated Na+ channels (subtypes Na(v) 1.1, 1.3, and 1.6) in the unmyelinated, prelaminar, and laminar optic nerve was found. This distribution co-localised both with areas of high COX activity and strong immunolabelling for COX subunits I and IV.

CONCLUSIONS

Increased numbers of mitochondria in the prelaminar optic nerve have previously been interpreted as indicating a mechanical hold up of axoplasmic flow at the lamina cribrosa. These results suggest that this increased mitochondrial density serves the higher energy requirements for electrical conduction in unmyelinated axons in the prelaminar and laminar optic nerve and is not a reflection of any mechanical restriction. This could explain why optic neuropathies typically occur in primary inherited mitochondrial diseases such as Leber's hereditary optic neuropathy, myoclonic epilepsy with ragged red fibres (MERRF), and Leigh's syndrome. Secondary mitochondrial dysfunction has also been reported in dominant optic atrophy, Friedreich's ataxia, tobacco alcohol amblyopia, Cuban epidemic optic neuropathy, and chloramphenicol optic neuropathy. These diseases are rare but these findings challenge the traditional theories of optic nerve structure and function and may suggest an alternative approach to the study of commoner optic neuropathies such as glaucoma.

Meeting Report: 10 Years of Progress: Report from Selected Presentations at the 19th ECTRIMS Congress, 1720 September 2003, Milan, Italy

The success of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) is notable, and Chris Polman (Amsterdam, the Netherlands), the new President of ECTRIMS, pointed out that the Congress had grown from an attendance of 50 delegates in 1982 to over 3000 at this 19th meeting. ECTRIMS 2003 provided an overview of recent achievements in clinical multiple sclerosis (MS) research, with sessions highlighting understanding and promoting functional and structural recovery, and the necessity and progress made in co-ordinating research efforts in MS. The impact of molecular biology, new perspectives in MRI and advances in treatment were covered in comprehensive reviews and original presentations. Five hundred stimulating posters from researchers around the world were also presented. Several satellite symposia, a young scientific investigators' session, an international workshop on remyelination in MS, a comprehensive exhibition and presentations of late-breaking research complemented the main programme.

The developing neurovascular anatomy of the embryo: a technique of simultaneous evaluation using fluorescent labeling, confocal microscopy, and three-dimensional reconstruction

The close spatial relationship between peripheral nerves and blood vessels in the adult is well known. However, evidence supporting the congruent development of these structures in embryos remains anecdotal. Neurovascular relationships also have been shown to be conserved in other vertebrates. This homology suggests that either peripheral nerves or blood vessels, or both, might have fundamental morphogenetic roles during embryologic development. Both peripheral nerves and blood vessels have been independently implicated as etiologic agents in the pathogenesis of congenital disabilities, and several congenital anomalies fit their distribution patterns. This article presents a technique for the simultaneous visualization of peripheral nerves and blood vessels at different stages in the developing embryo. The forelimbs of 310 quail embryos were dissected over a 1-year period. Peripheral nerves were labeled with the neural crest and axon antibody, HNK-1, followed by fluorescein-conjugated secondary antibodies. Blood vessels were labeled by a perfusion technique using the fluorescent dye, dioctadecyl-tetramethylindocarbocyanine. Specimens were processed and imaged in whole-mount with confocal microscopy, and images were reconstructed using three-dimensional modeling software. Both nerves and blood vessels seem to undergo a highly stereotypic sequence of development in the embryonic quail forelimb. Furthermore, the existence of a close spatial relationship between nerves and blood vessels suggests either a high degree of developmental interdependence or shared patterning mechanisms. This technique permits further evaluation of the possible role peripheral nerves and blood vessels might play in the pathogenesis of congenital disabilities and provides a starting point for further studies aimed at elucidating the means by which peripheral nerves and blood vessels are patterned in the forelimb of the avian embryo.

Mutation in the gene encoding ferritin light polypeptide causes dominant adult-onset basal ganglia disease

We describe here a previously unknown, dominantly inherited, late-onset basal ganglia disease, variably presenting with extrapyramidal features similar to those of Huntington's disease (HD) or parkinsonism. We mapped the disorder, by linkage analysis, to 19q13.3, which contains the gene for ferritin light polypeptide (FTL). We found an adenine insertion at position 460-461 that is predicted to alter carboxy-terminal residues of the gene product. Brain histochemistry disclosed abnormal aggregates of ferritin and iron. Low serum ferritin levels also characterized patients. Ferritin, the main iron storage protein, is composed of 24 subunits of two types (heavy, H and light, L) which form a soluble, hollow sphere. Brain iron deposition increases normally with age, especially in the basal ganglia, and is a suspected causative factor in several neurodegenerative diseases in which it correlates with visible pathology, possibly by its involvement in toxic free-radical reactions. We found the same mutation in five apparently unrelated subjects with similar extrapyramidal symptoms. An abnormality in ferritin strongly indicates a primary function for iron in the pathogenesis of this new disease, for which we propose the name 'neuroferritinopathy'.

Impact of poorly controlled hypertension on healthcare resource utilization and cost

OBJECTIVE

To examine the relation between blood pressure (BP) control and utilization and cost of healthcare resources.

STUDY DESIGN

A retrospective database study of managed care patients in New Mexico from January 1, 1996, to December 31, 1997.

PATIENTS AND METHODS

We stratified 1000 hypertensive patients into categories based on average and maximum BP. Antihypertensive medication use and cost, number of physician visits, and interval between hypertension-related physician visits were determined.

RESULTS

Medication costs increased progressively across all BP categories from lowest to highest, and higher average systolic BP (SBP) was significantly correlated with increased cost (P < .001). There were significant correlations between higher maximum BP and greater number of hypertension-related physician visits (P < .001). Mean number of visits for BP groups was 5.5 for patients with a maximum diastolic BP (DBP) < 85 mm Hg and 10.0 for those with a maximum DBP > or = 100 mm Hg (P < .001). Patients with a maximum SBP > or = 180 mm Hg averaged 9.7 visits, whereas those with a maximum SBP < 120 mm Hg averaged 4.1 visits (P < .001). Both SBP and DBP were significantly correlated with time to next visit (P < .001). Mean visit intervals ranged from 44 days for patients with an SBP < 85 mm Hg to 25 days for those with an SBP > or = 180 mm Hg (P < .001). A similar association was found between DBP and visit interval.

CONCLUSIONS

Poor control of hypertension is associated with higher drug costs and more physician visits. Aggressive treatment might help reduce managed care costs and resource utilization.

Patterns of radial dysmorphology with the VACTERL association in the adriamycin-exposed prenatal rat

The VACTERL association is an acronym for a constellation of abnormalities affecting the spinal column, anus, heart, trachea, esophagus, kidneys, and limbs that are seen in newborns. It has been shown that prenatal rats exposed to Adriamycin demonstrate a similar series of anomalies. It is the aim of this study to characterize the spectrum of limb anomalies in this model. Female Sprague-Dawley rats (N = 18; 14 experimental and 4 control) were used. After mating, pregnant animals received intraperitoneal injections of Adriamycin (2 mg per kilogram) on days 6, 7, 8, and 9 of gestation. Fetuses were recovered on day 21 of gestation. Ten experimental litters (42 fetuses) and two control litters (18 fetuses) underwent skeletal staining with Alizarin Red S stain. Four experimental litters (N = 18) and two control litters (N = 17) underwent histological study including staining for vascular and neural structures. Upper limb anomalies were found in 45% of the experimental animals, all including either hypoplasia or bending of the radius. The ulna was involved in 37% of the affected limbs. There were no isolated ulnar deformities. There were no histological differences noted. The spectrum of upper limb anomalies seen in the Adriamycin-exposed prenatal rat closely approximates, in incidence and morphology, the upper limb deformities seen with the VACTERL association in children. It is a reliable model for use in additional studies of the embryological mechanism by which these defects arise.

Phytonadione therapy in a multiple-drug overdose involving warfarin

We cared for a patient who ingested an unknown amount of acetaminophen with zopiclone and warfarin. The only liver function test that was abnormal was an increased international normalized ratio (INR), which remained elevated despite treatment with subcutaneous phytonadione and a prolonged infusion of N-acetylcysteine. An interaction between acetaminophen and warfarin may have decreased the hepatic metabolism of warfarin. The patient received numerous antibiotics that may have contributed to the increased INR. The prolonged elevation of INR also may have been due to infrequent administration of phytonadione.

Treatment of multiple sclerosis with interferon beta: an appraisal of cost-effectiveness and quality of life

OBJECTIVE

To evaluate the cost-effectiveness of interferon beta-1b (IFbeta-1b) for relapsing-remitting multiple sclerosis (RRMS).

METHODS

Construction of a cost-effectiveness model using published data on IFbeta-1b effectiveness and the natural history of RRMS, and new data on costs and quality of life (QoL) from a sample of 102 patients with RRMS and resident in northern England.

RESULTS

Poorer QoL was found for patients with multiple sclerosis compared with the general population; those who had had a relapse; those with worse states identified by a clinical measure (expanded disability status scale (EDSS)). Relapses have effects over several months. Health state valuations were higher than in the general population. Costs were higher in relapse than remission and for worse EDSS states. IFbeta-1b costs were larger than cost savings. The best cost-effectiveness estimate was pound28 700 per relapse avoided, which is pound809 900 per QALY gained; or pound328 300 per QALY gained allowing for effects of progression over 5 years. Estimates were robust to changes in assumptions.

CONCLUSIONS

The impact of multiple sclerosis on QoL is substantial. Future trials should base outcomes measurement on QoL and be better linked to natural history and cost data. IFbeta-1b produces important occasional short term QoL gains, but small gains in QALYs overall and large additional costs.