Hospital Sant Joan de Déu

Barcelona, SPAIN

Area of expertise and the Healthcare Provider’s contribution to care for patients within the MetabERN Network

The area of expertise of the Healthcare Provider within the ERN covers all the IMD described so far (small and complex molecule defects, energy defects and metabolic disorders affecting the central nervous system exclusively). However, our field of greater expertise and excellence is in those IMD that affects the brain exclusively in the paediatric age. We have all the facilities and internal structure/organization to offer clinical, biochemical and genetic diagnosis supported by other diagnostic procedures (brain image, neurophysiology, histopathology…). We will actively participate in different groups of diseases described within the metabERN network with a more specific and complex task in those categories of disorders. Our group has had the most active participation at the clinical and scientific levels. As examples, we have been co-founders of the first international network for the study of neurotransmitter related disorders:
I-NTD and have participated in the first European registry of intoxication disorders (E-IMD) as partners.
We have also been partners of the European project InNerMed (Information Network in Neurometabolic diseases). Therefore, in these groups of disorders, we play an active role in applying and validating new diagnostic tools, patient registries, and clinical guidelines. Regarding treatments of IMD, we are very cautious in applying the already approved protocols and international guidelines since we have been involved in the elaboration and validation of these recommendations.
Our internal structure in the unit is composed of the following specialised services:
The Neurology department (paediatricians, neurologists, and paediatric neurologists specialized in metabolic medicine) develops an important part of the clinical work since most of our patients have some neurological manifestation. We have a long tradition in the study of the treatment of neurometabolic diseases.
– The Nutrition and Gastroenterology department (paediatricians specialized in metabolic medicine, dieticians) take care of the diet treatments and the nutritional aspects of the patients. Hepatologists also collaborate in those IMD affecting the liver and in the liver transplantation programme with the Valle Hebrón Hospital in Barcelona.
– The Laboratories of biochemistry, molecular biology and pathology (clinical biochemists, laboratory technicians, pathologists, molecular and cell biologists) support the diagnosis and research. There is an emergency laboratory that covers 24-hour tests if required. There are also doctors on call for the
metabolic patients during 24 hours.
– Since 2013, the expanded neonatal screening includes not only PKU but 20 more IMD. Patients detected in half the south area of Catalonia (distribution designated by the Catalan government) are referred to our centre. The half north goes to Hospital Vall d’Hebrón (HVH) in Barcelona.

SPECIFIC TREATMENTS AND INTERVENTIONS PROVIDED BY THE HCPs

– Diet based treatments: restriction of proteins, lipids, and carbohydrate supplementation together with vitamins and cofactors depending on the disease (such as BH4 for PKU and some pterin disorders). We have treatment protocols for aminoacidopathies including urea cycle disorders, organic acidurias, beta-oxidation defects, carbohydrate diseases (fructosemia, galactosemia), ketogenic diet (GLUT-1 deficiency).
– Vitamin supplementation: vitamin B6, cobalamine, folate, thiamin, riboflavin, vitamines A/E, biotin for the specific metabolism and transport of these vitamins (pyridoxin dependent seizures, cobalamine defects, peripheral and cerebral folate deficiency, thiamine, riboflavin, vitamin E and biotin defects). Cobalamine, pyridoxine and, folate for the different types of homocystinuria.
– Amino acid supplements for IEM with protein restriction and defects in the amino acid synthesis .
– Pharmacological treatment for neurotransmitter deficiencies: L-Dopa+Carbidopa, 5-OH-tryptophan.
– Chelators and depurators: sodium benzoate, phenylbutirate, carbamylglutamate, carnitine, dichloroacetate, dichloropropionate, succinilacetone chelators (NTBC).
– Enzymatic replacement for lysosomal diseases.
– Intensive therapies to treat decompensations: extracorporeal depuration techniques.
– Gene therapy for the mucopolysaccharidoses (clinical trial).
– Others: betaine, creatine, dextromerorphan, lipoic acid, cysteamin, hemin arginate, diazoxide, octreotid.
Interventions:
– Diagnosis and therapy of hospitalized patients with all kind of IEM diseases.
– Specialized clinical management at the metabolic unit out-patient offices.
– The “Dietetic Kitchen” offers a basic treatment and support in the education of patients and families with IEM.
– The Pharmacy of the hospital constantly updates all the necessary orphan drugs required both in emergency situations and chronic treatments.
– Urgent biochemical analysis specific of IEM during 24 hours: glucose, ammonia, ions, redox status, lactate, ketone bodies, liver enzymes, urea, creatinine, clotting factors, CPK, triglycerides, uric acid. Amino acids and organic acids may be also urgently determined if the clinical situation requires those studies.
– Biochemical and genetic studies already described in I Area of Expertise of the Healthcare provider.
– Tissue culture (fibroblasts, lymphoblasts, ammiocytes) and biologic samples bank.
– Optic and electronic microscopy of muscle biopsy.

Angela Garcia Cazorla

Hospital Sant Joan de Déu, Esplugues. Barcelona, Spain.