G.P.2.08 SMA frequency in Poland

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Abstracts / Neuromuscular Disorders 17 (2007) 764–900

mouth are relatively frequent, clinical signs of swallowing abnormalities are infrequent in SMA 2 and do not occur in SMA 3. Further studies using an objective evaluation such as videofluoroscopy may help to clarify the presence and severity of swallowing abnormalities and suggest possible therapeutic options. doi:10.1016/j.nmd.2007.06.060

G.P.2.05 Improving the outcomes in children with severe spinal muscular atrophy with a proactive approach Chadehumbe, M. 1,*; Kalra, M. 2; Inge, T. 3; Knue, M. 1; Wong, B. 1 1 Cincinnati Children’s Hospital Medical Center, Pediatric Neurology, Cincinnati, United States; 2 Cincinnati Children’s Hospital Medical Center, Pediatric Pulmonary Medicine, Cincinnati, United States; 3 Cincinnati Children’s Hospital Medical Center, Pediatric General and Thoracic Surgery, Cincinnati, United States Majority of children with severe SMA do not survive past the second birthday. Failure to thrive and severe pneumonias are frequent complications. To evaluate the outcomes of patients with severe SMA managed with a proactive protocol. We performed a retrospective chart review of children with severe SMA treated at our institution between years 2000– 2006. Traditionally we treated children with severe SMA as complications arose – G-tube placement, Nissen Fundoplication (NF) and ventilatory support reactive to development of failure to thrive and pulmonary complications, respectively. With establishment of a multidisciplinary neuromuscular team, we adopted a proactive protocol that accommodated families that wanted aggressive supportive care once the diagnosis was made. The proactive approach focused on managing the predictable complications with laparoscopic G-tube placement with NF, aggressive airway clearance with the cough assist machine and non-invasive ventilatory support during sleep. Our outcome measures were survival, ability to maintain weight at least between 5th and 25th percentile with length in the 25th and 75th percentile, and length of intensive care unit stay following surgical procedures or pneumonias. Twelve children with severe SMA (type 0 and 1) were abstracted. Four patients were managed with the ‘‘proactive’’ approach and all (100%) are in good general health (ages: 21, 54, 36, 43 months). Of the eight managed with the ‘‘reactive’’ approach, only three (38%) survived, (ages, 63, 30, 23 months). Average age of death was 16 months. Optimal weight gain was seen in all four of the proactive group and in only one in the reactive group. Regarding length of stay in the intensive care unit following surgical procedures and pneumonias, the proactive group had short stays <72 h compared to lengthy stays of >5 days for the reactive group. Improved survival and decreased morbidity amongst severe SMA patients may be achieved with aggressive ‘‘proactive’’ care measures instituted by a multidisciplinary team. doi:10.1016/j.nmd.2007.06.061

complications following general anesthesia for surgical procedures. Our study describes results of a standardized extubation protocol designed to reduce post-operative respiratory complications in patients with SMA-1. A multidisciplinary team standardized a clinical protocol for extubation of SMA-1 patients which was followed by all clinical staff. Per protocol, airway clearance with cough assist is initiated pre-operatively. All patients are monitored post-operatively in the pediatric intensive care unit and are extubated to continuous BiPAP with gradual weaning of BiPAP support. Medical records of SMA-1 patients who underwent elective gastrostomy tube insertion following protocol implementation were retrospectively reviewed. Five patients with SMA-1 (mean age 9.8 months ± 3.03) underwent elective laparoscopic Nissen Fundoplication and gastrostomy tube insertion. Non-invasive ventilatory support during sleep was initiated pre-operatively in four of the five patients and all patients were receiving airway clearance by cough assist device. All patients were successfully extubated using the protocol and discharged home on BiPAP without oxygen supplementation. There were no major respiratory complications in the post-operative period. The most frequent minor complication was atelectasis. Conclusion: We report good pulmonary outcomes using a standard extubation protocol after general anesthesia and minimallyinvasive surgery in patients with SMA-1. doi:10.1016/j.nmd.2007.06.062

G.P.2.07 Spinal muscular atrophy plus arthrogryposis and congenital bone fractures: A case report Karasoy, H. *; Ozbay, O.; Yuceyar, N. Ege University Medical School Hospital, Neurology, Bornova-Izmir, Turkey Spinal muscular atrophy (SMA) plus arthrogryposis and congenital bone fractures has been described as a distinct and rare form of SMA. We report a 12-year-old girl presented with congenital fractures of both femur and multiple contractures of lower extremities, hypotonia, areflexia and psychomotor developmental delay. Family history was negative. She had no bulbar impairment. She was able to sit independently at age of 12 months. Electrophysiological studies performed at the age of 12 and 26 months revealed normal motor and sensory nerve studies with EMG showing chronic neurogenic changes prominent on the lower extremities. Serum CK was normal. Spinal cord lesions were excluded by spinal MRI. There was no deletion in the SMN gene. She was followed with physical therapy. She managed to speak when she was 3 years old. She could stand with support at 5 years of age and could walk with a walker at 10 years of age. There are few case reports of combined congenital long bone fractures, contractures and spinal muscular atrophy, and they died before they reached 2 years of age. This condition is not associated with SMN gene deletion in most reported cases. To our knowledge, this patient is the first case with spinal muscular atrophy, arthrogryposis and congenital fractures living beyond 10 years of age. doi:10.1016/j.nmd.2007.06.063

G.P.2.06 Reducing the morbidity in spinal muscular atrophy type 1 patients postoperatively by a standardized extubation protocol Chadehumbe, M. 1,*; Ednick, M. 2; Wong, B. 1; Knue, M. 1; Inge, T. 3; Kalra, M. 2 1 Cincinnati Children’s Hospital Medical Center, Pediatric Neurology, Cincinnati, United States; 2 Cincinnati Children’s Hospital Medical Center, Pediatric Pulmonary Medicine, Cincinnati, United States; 3 Cincinnati Children’s Hospital Medical Center, Pediatric General and Thoracic Surgery, Cincinnati, United States Spinal muscular atrophies (SMA) are characterized by weakness and atrophy of skeletal muscles musculature increasing the risk of pulmonary

G.P.2.08 SMA frequency in Poland Jedrzejowska, M. 1; Zimowski, J. 2; Sielska, D. 3; Kostera-Pruszczyk, A. 4; Milewski, M. 3; Jurek, M. 3; Hausmanowa-Petrusewicz, I. 1,* 1 Medical Research Centre, Polish Academy of Sciences, Neuromuscular Unit, Warsaw, Poland; 2 Institute of Psychiatry and Neurology, Department of Genetics, Warsaw, Poland; 3 National Research Institute of Mother and Child, Department of Medical Genetics, Warsaw, Poland; 4 Medical University of Warsaw, Department of Neurology, Warsaw, Poland

Abstracts / Neuromuscular Disorders 17 (2007) 764–900 The aim of the study was to estimate the frequency of SMA in Poland. The estimation was done on the basis of the metaanalysis of all molecular tests carried out in Poland in period 1998–2005, as well as on a carrier frequency of SMN1 deletion in Polish population. 770 SMA screening tests were performed with positive results in 567 cases, including 304 newly diagnosed SMA cases. Additionally 72 prenatal tests were performed, in 14 cases positive results were obtained. Assuming mean birth rate in Poland in this period at 370,475, SMA incidence was estimated at 1 per 9379 births. About 60% of all newly diagnosed patients suffered from severe form of SMA. This results did not confirm suggestions about higher incidence of mild form in Mid-East Europe. Using gene dosage analysis (MGB TaqMan probes) we determined the copy numbers of SMN1 in a group of 525 subjects with no family history of neuromuscular disorders. The carrier prevalence of SMN1 gene deletion was estimated at 1/35 (15/ 525) and the resultant incidence of SMA being 1 per 4900. The 4.95% (26/ 525) of normal controls showed 3 SMN1 copies, suggesting duplication of SMN1 gene on one chromosome. Some inconsistency in estimated SMA frequency may depend on many factors, e.g., misdiagnosed patients or early miscarriages of SMA fetuses. doi:10.1016/j.nmd.2007.06.064

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genes are ACE (as a regulator of muscle hemodynamics and function) and TGF (as a regulator of neuromuscular system development). To investigate if ACE ID and TGFb gene polymorphisms are associated with SMA phenotype in Romanian patients. Our study was carried out on 63 patients, 60 parents and 100 healthy controls. The SMA patients were classified in the three type of SMA corresponding to ISMAC criteria. All subjects were screened for the most common mutations (homozygous deletions of exon 7 and/or 8) in SMN genes and also for ACE ID and TGFb-809GA and -500CT polymorphisms using PCR based methods. We observed that homozygous mutations in SMN genes are present much frequent in type I (85.2%) than in type II (47.1%), type III (42.1%) patients or in controls (0%). These results are in agreement with some previous publications regarding Caucasian population. The Hardy–Weinberg equilibrium was calculated for all polymorphisms and it was observed that only the TGFb-509CT do not respect this condition. The heterozygous TGFb-800GA were observed with highest frequency in SMA patients than in control (ORGA = 1,5). The deleterious ACE DD genotype was more common in SMA type I group (48.14%) and it seems to modify the risk for disease (ORDD = 1,49 and ORD = 1,13). In conclusion, we can say that the ACE DD is associated with SMA and it may be a modifier factor at least for type I of disease. The contribution of TGFb polymorphisms to disease is much uncertain. However, because we do not found publications in the topics of low penetrance genes in SMA phenotype, all these results need to be further examined on a comprehensive large scale study.

G.P.2.09 Analysis of point mutations in the SMN1 gene in Czech SMA patients Hedvicakova, P. 1; Vondracek, P. 2; Fajkusova, L. 3; Zapletalova, E. 3,* 1 University Hospital Motol, Institute of Biology and Medical Genetics, Prague, Czech Republic; 2 University Hospital Brno, Department of Child Neurology, Brno, Czech Republic; 3 University Hospital Brno, Centre of Molecular Biology and Gene Therapy, Brno, Czech Republic Background: Spinal muscular atrophy is caused by homozygous deletion of the SMN1 gene in approximately 96% of cases. Four per cent of SMA patients have a combination of the deletion on one allele and an intragenic mutation on the second one. Objective: We performed analysis of point mutations in a set of our patients with suspicion of SMA and without homozygous deletion of the SMN1 gene. Methods: A quantitative test determining SMN1 copy number (using real-time PCR and/or MLPA analysis) was performed in 301 patients and only 1 SMN1 copy was detected in 14 of them. These 14 patients were screened using long-range PCR, PCR and sequencing for the presence of point mutations. Results and conclusions: We identified six mutations, p.Y272C (in three patients) and p.T274I, p.I33IfsX6, and p.A188S (each in one case). The mutations p.I33IfsX6 and p.A188S were not detected previously. The p.Y272C mutation has been shown to disrupt SMN oligomerization with a concomitant or downstream defect in Sm protein binding. In our set of SMA patients, we identified the mutation p.Y272C in association with 2 SMN2 copies in two patients (the first was SMAI and the second SMAII) and the same mutation in association with 3 SMN2 copies in one SMAII patient. The mutation p.T274I, which was shown to function similarly to the wild-type SMN1 was detected together with 2 SMN2 copies in one SMAIII patient. This work was supported by IGA MHCR, project 1A/8608-4, and the institutional support MSM0021622415. doi:10.1016/j.nmd.2007.06.065

doi:10.1016/j.nmd.2007.06.066

G.P.2.11 Spinal muscular atrophy. The mutational spectra in children from Western Sweden Darin, N. 1,*; Arkblad, E. 2; Kroksmark, A. 1; Berg, K. 2; Holmberg, E. 2; Nordling, M. 2; Tulinius, M. 1 1 Institute of Clinical Sciences, Department of Pediatrics, Go¨teborg, Sweden; 2 Institute of Biomedicine, Department of Genetics, Go¨teborg, Sweden Spinal muscular atrophy (SMA) is an autosomal recessive disease associated with degeneration of the anterior horn cells of the spinal cord. SMA is caused by reduced levels of the survival motor neuron (SMN) protein. Multiplex ligation-dependent probe amplification (MLPA) is a modern quantitative molecular method. Applied to SMA it improves diagnostics by simultaneously giving the gene-dosage of several target-sequences both in the SMN1-gene and in the SMN2-gene, as well as two target sequences in each of the flanking genes. In a population-based study we have identified 43 children with SMA diagnosed in Western Sweden between 1982 and 2005. MLPA analysis was performed in 35 index patients. All patients with SMA type I had two copies of SMN2. Six out of the seven patients with SMA type II had three copies of SMN2 while four copies were present in one patient. Of the patients with SMA type III analysed so far, six had four copies of SMN2 and three had three copies of SMN2. Our results confirm the ameliorating influence of SMN2 on the severity of SMA in a population-based cohort of well characterized patients. Children with SMA type I mostly had no copies of BIRC1 (NAIP) but otherwise there were no correlation between the number of BIRC copies and the type of SMA. doi:10.1016/j.nmd.2007.06.067

G.P.2.10 Are the ACE ID and TGFb polymorphisms involved in SMA phenotype? Apostol, P. *; Cimponeriu, D.; Stavarachi, M.; Toma, M.; Radu, I.; Gavrila, L. University of Bucharest, Institute of Genetics, Bucharest, Romania The variable severity of spinal muscular atrophy (SMA) is probably influenced by some low penetrance genes. We speculated that two of such

G.P.2.12 Spinal muscular atrophy and P213S polymorphism in L-selectin gene: A case-control study in Romanian subjects Stavarachi, M. 1,*; Apostol, P. 1; Cimponeriu, D. 1; Toma, M. 1; Butoianu, N. 2; Burloiu, C. 2; Magureanu, S. 2; Radu, I. 1; Gavrila, L. 1 1 University of Bucharest – Institute of Genetics, Human Genome, Bucharest, Romania; 2 Al. Obregia Hospital, Bucharest, Romania