Table 3 Acute and chronic presentations of MMA/PA

Neonatal sepsis-like picture, temperature instability, respiratory distress, hyperventilation

Often episodic characteristic signs and symptoms

Nervous system

Nervous system

• Altered level of consciousness (from lethargy and somnolence to coma) mimicking encephalitis or drug intoxication

• Hypotonia

•Developmental delay (learning disabilities, intellectual disability)

• Acute encephalopathy

•Movement disorders/dystonia

• Seizures (in general not isolated but in the context of altered level of consciousness)

• Seizures

• Movement disorders (more frequent in PA)

• Optic atrophy

• Stroke-like episodes (more frequent in MMA)

• Psychiatric symptoms (hallucinations, psychotic attacks)

Gastrointestinal system

Gastrointestinal system

•Vomiting and feeding difficulties

•Recurrent vomiting with ketoacidosis

• Abnormal feeding behavior (anorexia)

•Failure to thrive

• Constipation

• Pancreatitis

Hematologic findings

Hematologic findings

• Neutropenia, pancytopenia

• Neutropenia, pancytopenia

• Secondary hemophagocytosis (rare)

Heart

Heart (more frequent in PA)

• Acute cardiac failure (mostly on basis of cardiomyopathy)

• Cardiomyopathy

• Arrhythmias

• Prolonged QTc interval in ECG

Kidney (more frequent in MMA)

•Chronic renal failure in MMA

Other

• Dermatitis

• Hearing loss