Mannose phosphate isomerase-congenital disorder of glycosylation (MPI-CDG) deficiency is a rare subtype of congenital disorders of protein N-glycosylation. It is characterised by deficiency of MPI caused by pathogenic variants in MPI gene. The manifestation of MPI-CDG is different from other CDGs as the patients suffer dominantly from gastrointestinal and hepatic involvement whereas they usually do not present intellectual disability or neurological impairment. It is also one of the few treatable subtypes of CDGs with proven effect of oral mannose. This article covers a complex review of the literature and recommendations for the management of MPI-CDG with an emphasis on the clinical aspect of the disease. A team of international experts elaborated summaries and recommendations for diagnostics, differential diagnosis, management, and treatment of each system/organ involvement based on evidence-based data and experts' opinions. Those guidelines also reveal more questions about MPI-CDG which need to be further studied.

Centro de Genética Médica Jacinto de Magalhães Centro de Referência Doenças Hereditárias do Metabolismo Centro Hospitalar Universitário do Porto Unit for Multidisciplinary Research in Biomedicine ICBAS UP Porto Portugal

Centro de Referência Doenças Hereditárias do Metabolismo Centro Hospitalar Universitário do Porto Porto Portugal

Department of Biochemistry Assistance Publique Hôpitaux de Paris Bichat Hospital Paris France

Department of Clinical Genomics and Laboratory of Medical Pathology Mayo Clinic Rochester Minnesota USA

Department of Clinical Genomics Mayo Clinic Rochester Minnesota USA

Department of Development and Regeneration KU Leuven Leuven Belgium

Department of Metabolic Diseases JUMC Krakow and NSSU University Hospital Krakow Poland

Department of Paediatrics and Metabolic Center University Hospitals Leuven Leuven Belgium

Department of Paediatrics Otto von Guericke University Magdeburg Germany

Department of Pediatrics and Adolescent Medicine 1st Faculty of Medicine Charles University and General University Hospital Prague Prague Czech Republic

Department of Pediatrics Congenital Metabolic Unit University Clinical Hospital of Santiago University of Santiago de Compostela IDIS CIBERER MetabERN Santiago de Compostela Spain

Group of Metabolism Biocruces Bizkaia Health Research Institute Linked Clinical Group of Rare Diseases CIBER Barakaldo Spain

Hemophilia Care Centre Hematology Unit Hôpital Necker Assistance Publique Hôpitaux de Paris Paris France

INSERM U1149 Centre de Recherche sur l'Inflammation and Université Paris 7 Denis Diderot Paris France

INSERM UMR1193 Mécanismes Cellulaires et Moléculaires de l'Adaptation au Stress et Cancérogenèse Université Paris Saclay Châtenay Malabry France

Medical Genetic Department King Faisal Specialist Hospital and Research Center Alfaisal University Riyadh Saudi Arabia

Metabolomics Expertise Center CCB VIB Leuven Belgium

Reference Center of Inherited Metabolic Diseases Necker Hospital APHP University Paris Descartes Filière G2M MetabERN Paris France

Reference Center of Liver Diseases Necker Hospital Assistance Publique Hôpitaux de Paris University Paris Descartes Paris France

Service d'Hématologie Biologique Hôpital Necker Assistance Publique Hôpitaux de Paris Université Paris Saclay Paris France

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