Sandra Obikawa Kyosen

Prognostic factors for the late onset Pompe disease with enzyme replacement therapy: From our experience of 4 cases including an autopsy case

We report 4 cases of late onset glycogen storage disease type II (GSD II) or Pompe disease (OMIM #232300), under enzyme replacement therapy (ERT) with recombinant human acid alpha glucosidase (rh-GAA, OMIM *606800). In these 4 cases, we focused on the case of a 28-years-old man, whose condition at the ERT starting was the worst and resulted in poor prognosis. The autopsy was done under his familys permission, and revealed severe accumulation of glycogen in his muscle, especially diaphragm or iliopsoas, and pulmonary veno-occlusive disease (PVOD) which resulted in severe pulmonary hypertension (PH). This is the first report of PVOD as the cause of PH in Pompe disease. We studied this case comparing to another 3 cases of late onset Pompe disease under the same course of ERT in our hospital, and the average data of the group of late onset Pompe disease with severe pulmonary insufficiency receiving ERT, supposed that low score of the body mass index (BMI) on the baseline, the presence of specific genotype (p.R600C), and signs of pulmonary dysfunction suggesting PH (tachypnea, ultrasound cardiography data) were factors that influenced the prognosis. For a better prognosis in the late onset Pompe disease, an early diagnosis for the early start of ERT before the onset of respiratory failure should be important, and the deliberate management and care should be needed even after the ERT start, especially for severe cases including pulmonary dysfunction.

Neonatal gene transfer using lentiviral vector for murine Pompe disease: long-term expression and glycogen reduction

Pompe disease results from the deficiency of the lysosomal enzyme acid α-glucosidase (GAA), leading to accumulated glycogen in the heart and the skeletal muscles, which causes cardiomyopathy and muscle weakness. In this study, we tested the feasibility of gene therapy for Pompe disease using a lentivirus vector (LV). Newborn GAA knockout mice were treated with intravenous injection of LV encoding human GAA (hGAA) through the facial superficial temporal vein. The transgene expression in the tissues was analyzed up to 24 weeks after treatment. Our results showed that the recombinant LV was efficient not only in increasing the GAA activity in tissues but also in decreasing their glycogen content. The examination of histological sections showed clearence of the glycogen storage in skeletal and cardiac muscles 16 and 24 weeks after a single vector injection. Levels of expressed hGAA could be detected in serum of treated animals until 24 weeks. No significant immune reaction to transgene was detected in most treated animals. Therefore, we show that LV-mediated delivery system was effective in correcting the biochemical abnormalities and that this gene transfer system might be suitable for further studies on delivering GAA to Pompe disease mouse models.

Guidelines to diagnosis and monitoring of Fabry disease and review of treatment experiences.

Ana Maria Martins, MD, PhD, Vânia D’Almeida, MD, Sandra Obikawa Kyosen, MD, Edna Tiemi Takata, MD, Alvimar Goncalves Delgado, MD, PhD, Ângela Maria Barbosa Ferreira Goncalves, MD, Caio Cesar Benetti Filho, MD, Dino Martini Filho, MD, Gilson Biagini, MD, Helena Pimentel, MD, Hugo Abensur, MD, PhD, Humberto Cenci Guimaraes, MD, Jaelson Guilhem Gomes, MD, Jose Sobral Neto, MD, PhD, Luiz Octavio Dias D’Almeida, PhD, Luiz Roberto Carvalho, MD, Maria Beatriz Harouche, MD, Maria Cristina Jacometti Maldonado, MD, Osvaldo J. M. Nascimento, PhD, Paulo Sergio dos Santos Montoril, MD, and Ricardo Villela Bastos, MD

Enzyme Replacement Therapy in Mucopolysaccharidosis II Patients Under 1 Year of Age

Mucopolysaccharidosis (MPS) II, or Hunter syndrome, is a lysosomal storage disease characterized by multi-systemic involvement and a progressive clinical course. Enzyme replacement therapy with idursulfase has been approved in more than 50 countries worldwide; however, safety and efficacy data from clinical studies are currently only available for patients 1.4 years of age and older. Sibling case studies of infants with MPS I, II, and VI who initiated ERT in the first weeks or months of life have reported no new safety concerns and a more favorable clinical course for the sibling treated in infancy than for the later-treated sibling. Here we describe our experiences with a case series of eight MPS II patients for whom idursulfase treatment was initiated at under 1 year of age. The majority of the patients were diagnosed because of a family history of disease. All of the infants displayed abnormalities consistent with MPS II at diagnosis. The youngest age at treatment start was 10 days and the oldest was 6.5 months, with duration of treatment varying between 6 weeks and 5.5 years. No new safety concerns were observed, and none of the patients experienced an infusion-related reaction. All of the patients treated for more than 6 weeks showed improvements and/or stabilization of some somatic manifestations while on treatment. In some cases, caregivers made comparisons with other affected family members and reported that the early-treated patients experienced a less severe clinical course, although a lack of medical records for many family members precluded a rigorous comparison.

Alternative laronidase dose regimen for patients with mucopolysaccharidosis I: a multinational, retrospective, chart review case series

BackgroundEnzyme replacement therapy (ERT) with laronidase (recombinant human α-L-iduronidase, Aldurazyme®) is indicated for non-neurological signs and symptoms of mucopolysaccharidosis type I (MPS I). The approved laronidase dose regimen is weekly infusions of 0.58mg/kg, however, patients and caregivers may have difficulty complying with the weekly regimen. We examined clinical outcomes, tolerability, compliance, and satisfaction in a series of patients who switched to every other week infusions.MethodsThis multinational, retrospective, chart review case series analyzed data from 20 patients who had undergone ERT with laronidase 0.58mg/kg weekly for more than one year, and who then switched to 1.2mg/kg every other week.ResultsThe majority of patients had attenuated MPS I phenotypes (9 with Hurler-Scheie and 8 with Scheie syndromes) and 3 patients had severe MPS I (Hurler syndrome). Most patients presented with organomegaly (17/20), umbilical and/or inguinal hernia (16/20), cardiac abnormalities (17/20), musculoskeletal abnormalities (19/20), and neurological and/or developmental deficits (15/20). Following laronidase treatment, signs stabilized or improved. No deterioration or reversal of clinical outcome was noted in any patient who switched from the weekly dose of 0.58mg.kg to 1.2mg/kg every other week. There were no safety issues during the duration of every other week dosing. Patient compliance and satisfaction with the dosing regimen were greater with every other week dosing than weekly dosing.ConclusionsAn alternative dose regimen of 1.2mg/kg laronidase every other week was well tolerated and clinically similar to the standard dose for patients who were stabilized with weekly 0.58 mg/kg for one year or more. When an individualized approach to laronidase therapy is necessary, every other week dosing may be an alternative for patients with difficulty receiving weekly infusions.

Novel GAA mutations in patients with Pompe disease.

Pompe disease is an autosomal recessive disorder linked to GAA gene that leads to a multi-system intralysosomal accumulation of glycogen. Mutation identification in the GAA gene can be very important for early diagnosis, correlation between genotype-phenotype and therapeutic intervention. For this purpose, peripheral blood from 57 individuals susceptible to Pompe disease was collected and all exons of GAA gene were amplified; the sequences and the mutations were analyzed in silico to predict possible impact on the structure and function of the human protein. In this study, 46 individuals presented 33 alterations in the GAA gene sequence, among which five (c.547-67C>G, c.547-39T>G, p.R437H, p.L641V and p.L705P) have not been previously described in the literature. The alterations in the coding region included 15 missense mutations, three nonsense mutations and one deletion. One insertion and other 13 single base changes were found in the non-coding region. The mutation p.G611D was found in homozygosis in a one-year-old child, who presented low levels of GAA activity, hypotonia and hypertrophic cardiomyopathy. Two patients presented the new mutation p.L705P in association with c.-32-13T>G. They had low levels of GAA activity and developed late onset Pompe disease. In our study, we observed alterations in the GAA gene originating from Asians, African-Americans and Caucasians, highlighting the high heterogeneity of the Brazilian population. Considering that Pompe disease studies are not very common in Brazil, this study will help to better understand the potential pathogenic role of each change in the GAA gene. Furthermore, a precise and early molecular analysis improves genetic counseling besides allowing for a more efficient treatment in potential candidates.

Lysosomal Acid Lipase Deficiency: Report of Five Cases across the Age Spectrum

Lysosomal acid lipase (LAL) deficiency is an autosomal recessive lysosomal storage disorder caused by mutations in the LIPA gene that leads to premature organ damage and mortality. We present retrospective data from medical records of 5 Brazilian patients, showing the broad clinical spectrum of the disease.

The Challenge of Diagnosis and Indication for Treatment in Fabry Disease

Fabry disease, caused by deficient alpha-galactosidase A lysosomal enzyme activity, remains challenging to health-care professionals. Laboratory diagnosis in males is carried out by determination o...

Effects of Aerobic Exercise Training in Late-Onset Pompe Disease Before and 1 Month after Enzyme Replacement Therapy

Pompe disease is a progressive multisystem disease caused by a lysosomal acid α-glycosidase enzyme (GAA) defi ciency, resulting in lysosomal accumulation of glycogen. The late-onset form is characterized by progressive skeletal and respiratory muscle dysfunction leading to functional disability and impairment of quality of life. Enzyme replacement therapy (ERT) and treatments, such as protein-enriched diet and exercise training, have been proposed as possible countermeasures for muscle impairment in patients with late-onset Pompe disease (LOPD). However, there are no established guidelines on therapeutic exercise for individuals with LOPD, and evidence of a benefi cial effect of exercise training is relatively scarce in these patients, and is mainly before receiving ERT. This retrospective study reports the results of a home-based submaximal aerobic exercise on functional capacity and pulmonary function in a patient with LOPD with mild respiratory manifestation and moderate skeletal muscle disease, prior to ERT regimen and 1 month after receiving ERT.

Effects of Exercise Training on Functional Capacity and Quality of Life in a Patient with Late-Onset Pompe Disease Receiving Enzyme Replacement Therapy

Pompe disease (PD) causes a progressive muscular weakness and impairment of patients’ mobility. Many patients develop intolerance to exercise due to reduced activity and consequent decline in muscle function. Exercise training prevents physical deconditioning and muscle wasting. Enzyme replacement therapy (ERT) was recently introduced, and has modifi ed the course of the disease. Other therapeutic interventions, such as exercise training, have been proposed as possible countermeasures for muscle impairment in patients with late-onset PD. We report the results of a 12-week home exercise training program on functional capacity and quality of life in a 20-year-old male patient with PD receiving ERT for 2 years.