Kristian Borg

Management of postpolio syndrome.

Postpolio syndrome is characterised by the exacerbation of existing or new health problems, most often muscle weakness and fatigability, general fatigue, and pain, after a period of stability subsequent to acute polio infection. Diagnosis is based on the presence of a lower motor neuron disorder that is supported by neurophysiological findings, with exclusion of other disorders as causes of the new symptoms. The muscle-related effects of postpolio syndrome are possibly associated with an ongoing process of denervation and reinnervation, reaching a point at which denervation is no longer compensated for by reinnervation. The cause of this denervation is unknown, but an inflammatory process is possible. Rehabilitation in patients with postpolio syndrome should take a multiprofessional and multidisciplinary approach, with an emphasis on physiotherapy, including enhanced or individually modified physical activity, and muscle training. Patients with postpolio syndrome should be advised to avoid both inactivity and overuse of weak muscles. Evaluation of the need for orthoses and assistive devices is often required.

Sporadic inclusion body myositis: Pilot study on the effects of a home exercise program on muscle function, histopathology and inflammatory reaction

OBJECTIVE To evaluate the safety and effect of a home training program on muscle function in 7 patients with sporadic inclusion body myositis. DESIGN The patients performed exercise 5 days a week over a 12-week period. METHODS Safety was assessed by clinical examination, repeated muscle biopsies and serum levels of creatine kinase. Muscle strength was evaluated by clinical examination, dynamic dynamometer and by a functional index in myositis. RESULTS Strength was not significantly improved after the exercise, however none of the patients deteriorated concerning muscle function. The histopathology was unchanged and there were no signs of increased muscle inflammation or of expression of cytokines and adhesion molecules in the muscle biopsies. Creatine kinase levels were unchanged. A significant decrease was found in the areas that were positively stained for EN-4 (a marker for endothelial cells) in the muscle biopsies after training. CONCLUSION The home exercise program was considered as not harmful to the muscles regarding muscle inflammation and function. Exercise may prevent loss of muscle strength due to disease and/or inactivity.

Intravenous immunoglobulin for post-polio syndrome: a randomised controlled trial

BACKGROUND Survivors of poliomyelitis often develop increased or new symptoms decades after the acute infection, known as post-polio syndrome. Production of proinflammatory cytokines within the CNS indicates an underlying inflammatory process, accessible for immunomodulatory treatment. We did a multicentre, randomised, double-blind, placebo-controlled study of intravenous immunoglobulin in post-polio syndrome. METHODS 142 patients at four university clinics were randomly assigned infusion of either 90 g in total of intravenous immunoglobulin (n=73) or placebo (n=69) during 3 consecutive days, repeated after 3 months. Seven patients were withdrawn from the study. Thus, 135 patients were assessed per protocol. Primary endpoints were muscle strength in a selected study muscle and quality of life as measured with the SF-36 questionnaire (SF-36 PCS). Secondary endpoints were 6-minute walk test (6MWT), timed up and go (TUG), muscle strength in muscles not chosen as the study muscle, physical activity scale of the elderly (PASE), visual analogue scale (VAS) for pain, multidimensional fatigue inventory (MFI-20), balance, and sleep quality. Outcome tests were done immediately before the first infusion and 3 months after the second infusion. This study is registered with , number NCT00160082. FINDINGS Compared with baseline, median muscle strength differed by 8.3% between patients receiving intravenous immunoglobulin and placebo, in favour of the treatment group (p=0.029). SF-36 PCS did not differ significantly between the groups after treatment (p=0.321). Differences in the subscale vitality score (p=0.042) and PASE (p=0.018) favoured the active treatment group. MFI-20, TUG, muscle strength in the muscles not chosen as the study muscle, 6MWT, balance, and sleep quality did not differ between groups. For the whole study population there was no significant change in pain, as determined by VAS. Nevertheless, patients who reported pain at the study start improved in the intervention group but not in the placebo group (p=0.037). Intravenous immunoglobulin was well tolerated. INTERPRETATION Intravenous immunoglobulin could be a supportive treatment option for subgroups of patients with post-polio syndrome. Further studies on responding subgroups, long-term effects, and dosing schedules are needed.

Prior poliomyelitis-evidence of cytokine production in the central nervous system

In order to study the role of a possible inflammatory reaction in the post-polio syndrome (PPS) four key cytokines were determined by means of mRNA expression in mononuclear cells from cerebrospinal fluid (CSF) and peripheral blood of 13 patients. Data were compared with those of samples from eight non-inflammatory control persons. The PPS-patients displayed increased numbers of CSF cells expressing mRNA for TNF-alpha (p<0.02), IFN-gamma (p<0.02), IL-4 (p<0.001) and IL-10 (p<0.05), in comparison to the non-inflammatory controls. As positive controls, samples from patients with Multiple Sclerosis (MS) were examined. We conclude that there is a chronic intra CNS expression of inflammatory cytokines in PPS, in the range of that in MS, a well known neuroinflammatory disease. However, the pathogenic significance of this is unclear.

Muscle fiber atrophy in leg muscles after botulinum toxin type A treatment of cervical dystonia

Previous electrophysiologic studies on the effects of local injections of botulinum toxin type A (BTX-A) have indicated impaired neuro-muscular transmission in distant muscles. To further study possible distant effects of repeated BTX-A injections, we obtained percutaneous muscle biopsies of the vastus lateralis muscle from 11 patients with cervical dystonia. We examined the biopsies with histopathology and morphometry, and compared them with age-matched healthy controls. There was an increased frequency of angular atrophic type IIB fibers in the patient group, and the mean size of IIB fibers was significantly smaller (p < 0.05). In addition, there was a negative correlation between accumulated dose of botulinum toxin and relative size of type IIA fibers (p < 0.05). We postulate that the observed atrophy is due to distant effects of botulinum toxin causing progressive denervation-like changes in non-treated muscle. This observation calls for further, prospective studies of the long-term effects of the treatment.

Identification of novel candidate protein biomarkers for the post-polio syndrome - implications for diagnosis, neurodegeneration and neuroinflammation.

Survivors of poliomyelitis often develop increased or new symptoms decades after the acute infection, a condition known as post-polio syndrome (PPS). The condition affects 20-60% of previous polio patients, making it one of the most common causes of neurological deficits worldwide. The underlying pathogenesis is not fully understood and accurate diagnosis is not feasible. Herein we investigated whether it was possible to identify proteomic profile aberrations in the cerebrospinal fluid (CSF) of PPS patients. CSF from 15 patients with well-defined PPS were analyzed for protein expression profiles. The results were compared to data obtained from nine healthy controls and 34 patients with other non-inflammatory diseases which served as negative controls. In addition, 17 samples from persons with secondary progressive multiple sclerosis (SPMS) were added as relevant age-matched references for the PPS samples. The CSF of persons with PPS displayed a disease-specific and highly predictive (p=0.0017) differential expression of five distinct proteins: gelsolin, hemopexin, peptidylglycine alpha-amidating monooxygenase, glutathione synthetase and kallikrein 6, respectively, in comparison with the control groups. An independent ELISA confirmed the increase of kallikrein 6. We suggest that these five proteins should be further evaluated as candidate biomarkers for the diagnosis and development of new therapies for PPS patients.

Effects of high resistance training in patients with myotonic dystrophy.

Nine ambulatory subjects with myotonic dystrophy participated in a supervised 12-week progressive high-resistance training program. Knee extensor muscles were trained 3 times a week with free weights, 3 x 10 repetitions at 80% of 1RM. One leg was randomly chosen for training and the other served as control. Six patients completed the training program. In the trained leg, 1RM increased from 16.4 +/- 3.4 kg to 21.8 +/- 2.6 kg (p = 0.0002). There was no difference between pre- and post-training concentric or eccentric isokinetic values at 30 degrees/second in either leg. Muscle biopsy from m. vastus lateralis in the trained leg revealed no systematic difference in the degree of histopathological abnormalities before and after training. After training, there was a tendency toward increase in cross-sectional area of type I muscle fibres. However, the number of subjects was too small to draw conclusions regarding the effects of training on the histopathological changes. Magnetic resonance imaging revealed no difference in the m. quadriceps area after training. In conclusion, patients with myotonic dystrophy improved their muscle strength without any observed negative side effects after a 12-week high-resistance training program.

Focal spasticity therapy with botulinum toxin: effects on function, activities of daily living and pain in 100 adult patients.

OBJECTIVE Analysis of the effects of a comprehensive focal spasticity program in adult patients. DESIGN Retrospective study of an out-patient cohort. PATIENTS One hundred patients were enrolled in the study (54 men and 46 women, mean age 41 years (SD 14). Cerebral palsy and stroke were equally common (80% in total). The remaining patients had miscellaneous diagnoses, including traumatic brain injury. METHODS On average 230 units (SD 101) of botulinum toxin A Botox was given for 227 principal therapy targets chosen by the patient or the caregiver. One patient could have several targets for therapy. Administration of botulinum toxin was combined with 260 additional therapeutic interventions, most of which were forms of physical therapy. The effects were assessed after 6 weeks and compared with baseline functional abilities 1-2 weeks prior to therapy. RESULTS Improvement was observed for 211 (93%) therapy targets, no change in 15 (7%), and impairment in 1, corresponding to an overall improvement in 90 patients (90%), 9 unchanged (9%) and worsening in 1. Spasticity assessment (Ashworth scale 0-4; 30 patients) showed a statistically significant improvement (median at baseline was 3 vs 2 after therapy, mean difference 1.2, p<0.001). CONCLUSION Improvement was observed in >or=90% of patients and in their principal therapeutic targets in a cohort receiving their first focal spasticity treatment with botulinum toxin A and additional therapy. A strict strategy for patient selection and comprehensive management was followed.

Genetic linkage of Welander distal myopathy to chromosome 2p13

Welander distal myopathy (WDM) is an autosomal dominant myopathy with late‐adult onset characterized by slow progression of distal muscle weakness. The disorder is considered a model disease for hereditary distal myopathies and is almost only seen in Sweden and some parts of Finland. A genomewide screening has been performed in initially two Swedish families with 400 highly polymorphic microsatellite markers. We report here that the disease is linked to chromosome 2p13. Seven additional nonrelated families have subsequently been mapped to the same area where a maximum two‐point LOD score of 17.97 was obtained with the marker D2S2113 at 0.0 recombination fraction. The region has been restricted by recombinations and the finding of a common shared haplotype through all analyzed families. This restricts the gene locus region to 2.4 cM. These findings provide evidence for the involvement of a single locus for WDM. The WDM region overlaps with the linkage region for Miyoshi myopathy and limb‐girdle muscular dystrophy 2B. The dysferlin gene responsible for these disorders is considered a primary candidate gene for WDM.

Motoneuron firing and isomyosin type of muscle fibres in prior polio.

In patients with prior polio there was an excessive use of remaining motor units and an absence of type II muscle fibres in the tibialis anterior (TA). In the present study, eight subjects with prior polio with more than 90% type I fibres in the TA were examined. The aim was to elucidate whether the lack of type II muscle fibres was due to a selective loss of motoneurons with high threshold and high axonal conduction velocity or due to a muscle fibre transition from type II to type I. There was no decrease of the proportion of motoneurons with high threshold and high axonal conduction velocity. Monoclonal antibodies against fast and slow myosin heavy chains (MHC) were used as histochemical markers and many muscle fibres of type I according to ATPase stainability showed a binding of both anti-fast and anti-slow MHC. It is suggested that the type I muscle fibre dominance in prior polio subjects with excessive use of TA during walking is due to a muscle fibre transition from type II to type I and not to a loss of one class of motor units.