Table 1

DiseaseEnzyme/Transporter DefectMain clinical features

GSD III (Cori-Forbes)Amylo-1,6 glucosidase (debranching enzyme)(distal) muscle weakness, cardiomyopathy, hepatomegaly, hypoglycaemia, growth retardation; osteoporosis, liver cirrhosis, hepatocellular carcinoma (later phase)

GSD V (Mc Ardle)Muscle phosphorylaseMuscle pain (exercise-induced), myoglobinuria

GSD VII (Tarui)Muscle phosphofructokinaseMuscle pain (+ vomiting, nausea), anaemia

CPT2-deficiencyCarnitine palmitoyl transferase 2Muscle weakness, cardiomyopathy, hepatomegaly, hypoglycaemia, seizures

MTP (Mitochondrial trifunctional protein)LCHAD, thiolase, enoyl-CoA hydrataseSudden death, “Reye-like” syndrome, respiratory dysfunction, capilliary leak syndrome, myopathy, myoglobinuria, cardiomyopathy, peripheral neuropathy, retinopathy

VLCAD-deficiencyVLCADCardiomyopathy, muscle weakness, myoglobinuria, hypoglycaemia, liver failure

MAD-deficiency (Glutaric aciduria type II)Electron transfer flavoprotein, electron transfer flavoprotein dehydrogenaseMuscle weakness, cardiomyopathy, hypoglycaemia, respiratory dysfunction, encephalopathy

CT-deficiencyCarnitine transporterSIDS, “Reye-like” syndrome, encephalopathy, muscle hypotonia, myalgia (later), psychomotor delay, dilatative cardiomyopathy. arrythmias, ventricular fibrillations

Respiratory chain defectsRespiratory chain complexes I–V (single or combined)Multisystem-disease (e.g., myopathy, cardiomyopathy, hepatopathy, epilepsy, developmental delay, mental retardation, etc.)