TITLE: 
                        
                            Reliability of enzyme assays in dried blood spots for diagnosis of 4 lysosomal storage disorders
                                
                                
                                    AUTHORS: 
                                            Romina Ceci, Pablo N. de Francesco, Juan M. Mucci, Lorena N. Cancelarich, Carlos A. Fossati, Paula A. Rozenfeld 
                                                    
                                                        KEYWORDS: 
                        Lysosomal Storage Disorders; Diagnosis; Dried Blood Spots; Sensitivity; Enzymatic Activity; Reliability 
                                                    
                                                    
                                                        JOURNAL NAME: 
                        Advances in Biological Chemistry,  
                        Vol.1 No.3, 
                        November
                                                        7,
                        2011
                                                    
                                                    
                                                        ABSTRACT: Introduction: Lysosomal storage disorders (LSD) are inherited diseases caused, in the majority of them, by the deficiency of lysosomal enzymatic activities. Ob-jectives: We aimed to analyze the usefulness of DBS samples for diagnosis of 4 LSDs, with the availability of a large quantity of patient samples. Design and methods: Blood samples from previously diagnosed patients with Fabry, Gaucher, Hunter, and Maro-teaux-Lamy syndromes and normal control individ-uals, were collected and dispen-sed in filter paper, and used for enzymatic activity determination. Results: Diagnosis of hemi/homo-zygous patients with Fabry, Hunter and Maroteaux-Lamy diseases using DBS samples showed ideal parameters of 100% sensitivity and specificity. DBS assay for Gaucher disease would need a posterior confirmatory step. Conclusions: Leukocyte measu-rement is the only reliable way to diagnose Gaucher disease. For Hunter, Fabry and Maroteaux-Lamy disorders discrimination between patients and controls seems adequate by DBS.