Clinical manifestation and classification of very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency
| Phenotype | Onset | Symptoms and signs | Severity | Frequency % | Genotype |
| Cardiomyopathic | Neonatal or early infancy | Cardiomyopathy, pericardial effusion, hepatic dysfunction, mildly elevated serum ammonia, lactate and creatine kinase levels | Severe, usually fatal without treatment | 47 | Two null mutations with no residual VLCAD enzyme activity |
| Hepatic | Late infancy or childhood | Recurrent hypoketotic hypoglycaemia, hepatic dysfunction | Intermediate, may be life threatening if not diagnosed and treated | 33 | ↓ |
| Myopathic | Adolescence to adulthood | Isolated skeletal muscle involvement with episodic muscle weakness, myalgia and rhabdomyolysis triggered by exercise or fasting | Mild | 20 | Two missense mutations or single amino acid deletions with residual enzyme activity |
Arrow represents the shift from two null mutations through to two missense mutations.