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Updated: May 11, 2026
04:41
Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
Persistent hyperlactacidaemia: about a clinical case
Ana Rita Saraiva Oliveira1, Rosalina Valente, José Ramos
1Department of Pediatrics, Hospital São Teotónio-CEntro Hospitalar Tondela Viseu, Viseu, Portugal. ritas-oliveira@hotmail.com
BMJ Case Reports
|May 25, 2013
Summary
Persistent high lactate levels in infants, especially with neurological symptoms, may indicate Leigh syndrome, a rare mitochondrial disorder. Early screening for mitochondrial diseases is crucial for timely diagnosis and management.
Area of Science:
- Biochemistry
- Genetics
- Neurology
Background:
- Lactate is a byproduct of anaerobic glycolysis, elevated during hypoperfusion or mitochondrial dysfunction.
- Leigh syndrome is a rare, progressive encephalomyopathy with distinct genetic causes but uniform neuroradiological and pathological features.
Observation:
- A 7-month-old infant with prematurity, psychomotor retardation, and epilepsy presented with cardio-respiratory arrest and persistent hyperlactacidaemia.
- Brain MRI with spectroscopy revealed bilateral thalamic and basal ganglia lesions with lactate peaks, suggestive of Leigh syndrome.
Findings:
- Enzymatic studies confirmed a pyruvate dehydrogenase deficiency.
- The findings highlight the link between persistent hyperlactacidaemia and Leigh syndrome.
Implications:
- Persistent hyperlactacidaemia in infants warrants screening for mitochondrial diseases.
- Early identification of Leigh syndrome is critical for managing this severe neurological condition.
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