Abstract Gaucher disease (GD) is one of the most common lysosomal disorders, occurring in approximately 1 in 40,000 live births worldwide. Since 2014 enzyme replacement therapy (ERT) with taliglucerase alfa has been the treatment of choice for adult patients with GD in Brazil. The aim of this study was to evaluate the long-term efficacy and safety of taliglucerase alfa in a cohort of Brazilian patients treated at a referral center for inborn errors of metabolism. All patients who received at least one infusion of the enzyme at the study center were considered eligible to participate. Patients were followed for adverse reactions and events throughout the study period. Platelets, hemoglobin, chitotriosidase activity, bone marrow burden (BMB) score, bone mineral density, and the severity score index (SSI) were analyzed. For patients who were switched to taliglucerase alfa from imiglucerase, the same variables were compared before and after the switch. At 9-year follow-up, all parameters of interest had remained stable or improved. The overall rate of adverse events was lower than in other studies that evaluated long-term ERT with taliglucerase, and no serious adverse events were considered related to treatment. Based on our findings, ERT with taliglucerase alfa is an effective and safe approach for treatment of patients with GD.

ABSTRACT Gaucher disease (GD) is an autosomal recessive lysosomal disorder caused by a disturbance in the metabolism of glucocerebroside in the macrophages. Most of its manifestations – hepatosplenomegaly, anemia, thrombocytopenia, and bone pain – are amenable to a macrophage-target therapy such as enzyme replacement. However, there is increasing evidence that abnormalities of the liver persist despite the specific GD treatment. In this work, we adapted histomorphometry techniques to the study of hepatocytes in GD using liver tissue of treated patients, developing the first morphometrical method for canalicular quantification in immunohistochemistry-stained liver biopsies, and exploring histomorphometric characteristics of GD. This is the first histomorphometric technique developed for canalicular analysis on histological liver biopsy samples.

Abstract Objectives: To characterize cases of suspected congenital disorders of glycosylation (CDG) investigated in a laboratory in southern Brazil using the transferrin isoelectric focusing TfIEF test from 2008 to 2017. Method: Observational, cross-sectional, retrospective study. The laboratory records of 1,546 individuals (median age = 36 months, 25–75 IQR = 10–108; males = 810) submitted to the TfIEF test during the period were reviewed. Results: Fifty-one individuals (3%) had an altered TfIEF pattern (5 ± 2.8 cases/year; median age = 24 months, 25–75 IQR = 11–57 months; males = 27, 53%). For 14 of them, data on diagnosis conclusion were available (classic galactosemia = 4; hereditary fructose intolerance = 4; peroxisomal diseases = 2; PMM2-CDG = 2; MPDU1-CDG = 1; SLC35A2-CDG = 1).Comparing the cases with the normal and altered TfIEF patterns, there was a higher prevalence of altered cases in the age group from 11 months to 3 years. There was an increase in the likelihood of change in TfIEF, especially in the presence of inverted nipples or liver disease. Conclusions: The data suggest that the investigation of a case with suspected CDG is a complex problem, being aggravated by the existence of other IEMs (inborn errors of metabolism) associated with altered TfIEF pattern and lack of access to confirmatory tests. The presence of inverted nipples and liver disease, especially in individuals aged 11 months to 3 years, should suggest the need for TfIEF investigation.

Resumo Objetivos: Caracterizar os casos com suspeita de CDG investigados em laboratório do sul do Brasil pelo exame de IEFTF de 2008 a 2017. Metodologia: Estudo observacional, transversal, retrospectivo. Foram revisadas as fichas laboratoriais de 1.546 indivíduos (mediana de idade = 36 meses, IQ 25-75 = 10-108; sexo masculino = 810) que fizeram o exame de IEFTF no período. Resultados: Cinquenta e um indivíduos (3%) apresentaram padrão alterado na IEFTF (5 ± 2,8 casos/ano; mediana de idade = 24 meses, IQ 25-75 = 11-57 meses; sexo masculino = 27, 53%). Para 14 deles, estavam disponíveis dados sobre a conclusão do diagnóstico (galactosemia clássica = 4; intolerância hereditária à frutose = 4; doenças peroxissomais = 2; PMM2-CDG = 2; MPDU1-CDG = 1; SLC35A2-CDG = 1). Comparando os casos com padrão normal e alterado na IEFTF, houve maior prevalência de casos alterados na faixa etária de 11 meses a 3 anos. Verificou-se um aumento na probabilidade de alteração na IEFTF principalmente na presença de mamilos invertidos ou de hepatopatia. Conclusões: Os nossos dados sugerem que a investigação de um caso com suspeita de CDG é complexa, é agravada pela existência de outros EIM associados a padrão alterado na IEFTF e pela falta de acesso a exames confirmatórios. A presença principalmente de mamilos invertidos e de hepatopatia em indivíduos na faixa etária de 11 meses a 3 anos deve sugerir a necessidade de investigação por IEFTF.

Abstract Mucolipidosis II and III (ML II and III) alpha/beta and ML III gamma are lysosomal diseases caused by GlcNAc-1-phosphotransferase deficiency. Previous data indicate that MLII patients have functionally impaired immune system that contributes to predisposition to infections.We evaluated the immunological phenotype of three Brazilian patients with ML III gamma. Our data suggest that the residual activity of GlcNAc-1-phosphotransferase in patients with ML III gamma is enough to allow the targeting of the lysosomal enzymes required for B-cell functions maintenance.

Abstract Leigh syndrome is a devastating neurodegenerative disease, typically manifesting in infancy or early childhood. Hallmarks of the disease are symmetrical lesions in the basal ganglia or brain stem on MRI, and a clinical course with rapid deterioration of cognitive and motor functions. It is genetically heterogeneous, causative mutations have been disclosed in mitochondrial DNA and nuclear genes involved in the process of energy production in the mitochondria .We investigated the whole mitochondrial DNA in three Brazilian patients with LS, based on their clinical and biochemical data, with the aim to identify the disease-causing mutations. In two of the patients, with complex I deficiency, a novel heteroplasmic variant m.4142G>T (p.R279L) in MT-ND1 and a recurrent homoplasmic mutation m.10197G>A (p.A47T) in MT-ND3 were identified. In the remaining patient, with complex IV deficiency, a de novo heteroplasmic variant in MT-CO1 m.6547T>C (p.L215P) was found. The molecular investigation in mitochondrial diseases have shifted their focus from mitochondrial DNA to nuclear DNA, however, mtDNA protein-coding genes are one of the important genetic causes of mitochondrial disorders for Leigh syndrome. This study expands the molecular and clinical spectrum associated with this disease.

Abstract Lysosomal diseases (LDs), also known as lysosomal storage diseases (LSDs), are a heterogeneous group of conditions caused by defects in lysosomal function. LDs may result from deficiency of lysosomal hydrolases, membrane-associated transporters or other non-enzymatic proteins. Interest in the LD field is growing each year, as more conditions are, or will soon be treatable. In this article, we review the diagnosis of LDs, from clinical suspicion and screening tests to the identification of enzyme or protein deficiencies and molecular genetic diagnosis. We also cover the treatment approaches that are currently available or in development, including hematopoietic stem cell transplantation, enzyme replacement therapy, small molecules, and gene therapy.

Abstract Hepatic glycogen storage diseases (GSDs) are genetic diseases associated with fasting hypoglycemia. Periodic intake of uncooked cornstarch is one of the treatment strategies available for those disorders. For reasons that are still not clear, patients with hepatic GSDs may be overweight. Aims: To assess nutritional status and body composition in patients with hepatic GSDs receiving uncooked cornstarch. Methods: The sample included 25 patients with hepatic GSD (type Ia = 14; Ib = 6; III = 3; IX? = 1; IX? = 1), with a median age of 11.0 years (interquartile range [IQR] = 9.0-17.5), matched by age and gender with 25 healthy controls (median age = 12.0 years, IQR = 10.0-17.5). Clinical, biochemical, and treatment-related variables were obtained from medical records. Nutritional status and body composition were prospectively evaluated by bioelectrical impedance. Results: Patients and controls did not differ with regard to age and gender. Height was significantly reduced in patients (median = 1.43 m, IQR = 1.25-1.54) in comparison to controls (median = 1.54 m, IQR = 1.42-1.61; P = .04). Body mass index for age z-score and fat mass percentage were higher in patients (median = 1.84, IQR = 0.55-3.06; and 27.5%, IQR = 22.6-32.0, respectively) than in controls (median = 0.86, IQR = ?0.55 to 1.82; P = .04 and 21.1%, IQR = 13.0-28.3; P = .01, respectively). When patients were stratified by type, those with GSD Ia had significantly higher adiposity (median fat mass = 28.7%, IQR = 25.3-32.9) than those with GSD III and GSD IX?/? (median fat mass = 20.9%, IQR = 14.9-22.6; P = .02). Conclusions: Our findings suggest that patients with hepatic GSD on treatment with cornstarch, especially those with GSD Ia, exhibit abnormalities in nutritional status and body composition, such as short stature and a trend toward overweight and obesity.

Abstract The clinical utility of serum ferritin as a biomarker of disease severity and prognosis in Gaucher disease (GD) is still debated. Here, we aimed to evaluate ferritin and its relation to clinicolaboratory parameters of GD patients seen at the Reference Center for Gaucher Disease of Rio Grande do Sul, Brazil, so as to gather evidence on the utility of ferritin as a biomarker of this condition. A retrospective chart review was performed collecting pre-and posttreatment data from GD patients. Eighteen patients with ferritin levels available before and after treatment were included in the study. Nine of these participants were males, and seventeen had type I GD. All patients were given either enzyme replacement (n = 16) or substrate reduction therapy (n = 2), and ferritin was found to decrease from 756 [318-1441] ng/mL at baseline to 521 [227-626] ng/mL (p=0.025) after 28.8 month soft treatment. Serum ferritin levels did not correlate with measures of disease severity, but showed an association with age at onset of treatment (ρ= 0.880; n = 18; p < 0.001). In conclusion, although serum ferritin did not correlate with disease severity, after a median 28.8 months of treatment, clinical outcomes had clearly improved, and ferritin levels had decreased.

The Latin American School of Human and Medical Genetics (ELAG) is the main course of its kind in the genetics field in Latin America. Here we describe the main challenges regarding the organization of such event, including how we obtain funding and how we proceed with student selection. Thus, we aim to share our experience with other groups that intend to follow this format to create similar events in other areas in this region of the world.

The specific treatment available for Fabry disease (FD) is enzyme replacement therapy (ERT) with agalsidase alfa or beta. A systematic review and meta-analysis was conducted to assess the efficacy and safety of ERT for FD. Only double-blind, randomized clinical trials (RCTs) comparing agalsidase alfa or beta and placebo were included. ERT with either agalsidase alfa or beta was considered similar for the purposes of analysis. Ten RCTs were identified, which showed improvements in neuropathic pain, in heart abnormalities and in globotriaosylceramide (GL-3) levels. A meta-analysis showed increased odds for fever, rigors, development of IgG antibodies to agalsidase, and no significant association with development of hypertension or reduction in the QRS complex duration on electrocardiogram. The RCTs included in this comparison enrolled few patients, were highly heterogeneous, and were focused mainly on surrogate endpoints, limiting any conclusions as to the real effect of ERT for FD. The available evidence suggests that response to ERT is variable across patient subgroups and that agalsidase may slow progression of FD, with slight improvement of existing changes. Nevertheless, many uncertainties remain, and further studies are necessary.