Clin Chem Lab Med 2015; 53(7): e157–e160 *Corresponding author: Prof. Nicola Volpi, Department of Life Sciences, University of Modena and Reggio Emilia, Via Campi 213/D, 41100 Modena, Italy, Phone: +39 59 2055543, Fax: +39 59 2055548, E-mail: volpi@unimo.it Giovanni V. Coppa, Lucia Zampini, Tiziana Galeazzi, Lucia Padella, Lucia Santoro and Orazio Gabrielli: Pediatric Division, Department of Clinical Sciences, Polytechnic University of the Marche, Ospedali Riuniti, Presidio Salesi, Ancona, Italy Francesca Maccari and Fabio Galeotti: Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy Livia Garavelli: Clinical Genetics Unit, Obstetric and Paediatric Department, Arcispedale S. Maria Nuova, Reggio Emilia, Italy Letter to the Editor Nicola Volpi*, Giovanni V. Coppa, Lucia Zampini, Francesca Maccari, Fabio Galeotti, Livia Garavelli, Tiziana Galeazzi, Lucia Padella, Lucia Santoro and Orazio Gabrielli Plasmatic and urinary glycosaminoglycan profile in a patient affected by multiple sulfatase deficiency DOI 10.1515/cclm-2014-0997 Received October 10, 2014; accepted December 9, 2014; previously published online January 7, 2015 Keywords: chondroitin sulfate; dermatan sulfate; gly- cosaminoglycans; heparan sulfate; multiple sulfatase deficiency. To the Editor, Multiple sulfatase deficiency (MSD, MIM# 272200) is an autosomal recessive disorder characterized by the defec- tive activity of all known sulfatases [1–3]. These enzymes catalyze the hydrolysis of sulfate ester bonds from a wide variety of substrates, such as macromolecules known as glycosaminoglycans (GAGs), and complex molecules, such as sulfolipids and steroid sulfates. Sulfatase defi- ciency causes eight inherited metabolic disorders in humans resulting in impaired desulfation of their natural substrates. In the case of lysosomal sulfatase deficiencies, non-catabolized sulfated substrates accumulate in the cells and tissues of patients, causing a lysosomal storage disorder (LSD). The phenotype of MSD patients includes the features of all disorders due to single sulfatase deficiencies [2, 3]. However, severe, moderate and mild forms of MSD have been described, based on different degrees of severity and age of onset of manifestations, probably due to a varia- ble residual activity of the different sulfatases that might account for the variable expression of specific clinical manifestations [2, 3]. As a consequence, MSD proves to be heterogeneous both at clinical and biochemical levels and, due to the rarity of MSD and its phenotypic complex- ity, some aspects have remained elusive. GAGs, hyaluronic acid, keratan sulfate, chondroitin sulfate (CS), dermatan sulfate (DS), heparan sulfate (HS) and heparin, are complex polydisperse polysaccharides [4] found inside cells, at the cell surface and extracellular matrices, and in biological fluids having biological and pharmacological activities of great importance in several pathological processes. To date, an accurate composi- tional and structural profile of GAGs excreted in biologi- cal fluids, plasma and urine, of an MSD patient has never been reported. This may be of some utility, considering the structural complexity of these macromolecules, the possi- ble different involvement of the various sulfatases in this disease, and the possible correlation between analytical response and clinical diagnosis/severity of the disorder as well as for possible therapeutic interventions. Aliquots of approximately 5 mL urine and approxi- mately 0.5 mL plasma in EDTA were obtained from our patient and frozen at –20 °C for analytical investigation with the informed consent of the patient. This study was approved by an Institutional Review Board of the Depart- ment of Clinical Sciences, Polytechnic University of the Marche, Ospedali Riuniti, Presidio Salesi, Ancona, Italy. Urinary and plasmatic CS, DS and HS/heparin were extracted and purified according to previous protocols [5–7] and analyzed by means of HPLC-fluorescence detec- tion after specific sequential treatment with chondroitinase ABC/chondroitinase B for CS/DS and a cocktail of hepari- nases I, II and III for HS [5–7]. Released unsaturated disac- charides by the action of lyases were fluorotagged with AMAC (2-aminoacridone) and separated by HPLC.