Episodic hypoglycemia with psi-hydroxy fatty acid excretion

Area of Science:

• Biochemistry
• Pediatric Medicine
• Metabolic Disorders

Background:

• Hypoglycemia in children can stem from various metabolic disturbances.
• Identifying specific biomarkers is crucial for diagnosing and managing pediatric metabolic conditions.

Observation:

• Two children with hypoglycemia exhibited elevated SGOT, low insulin, and increased urinary excretion of specific psi-hydroxy fatty acids (5-hydroxyhexanoic, 7-hydroxyoctanoic, 9-hydroxydecanoic).
• These unusual fatty acids were also detected in the urine of patients with Reye's syndrome and starvation ketonuria, but not in healthy children or children with uncomplicated hypoglycemia.
• The excretion of these acids persisted even when the children were clinically well and could be triggered by medium-chain triglyceride loads.

Findings:

• The ratio of psi-hydroxy fatty acids to 3-hydroxybutyric acid in the urine was significantly higher in affected patients compared to controls.
• Medium-chain triglyceride loading reproduced increased urinary psi-hydroxy fatty acids in affected children without other symptoms.
• Three children with hypoglycemia did not excrete these unusual acids while ill, and one did not excrete them after recovery.

Implications:

• The presence of specific urinary psi-hydroxy fatty acids may serve as a diagnostic marker for a distinct group of pediatric metabolic disorders.
• Further research is warranted to elucidate the specific metabolic pathways involved in the overproduction of these fatty acids.
• Understanding these metabolic alterations could lead to targeted therapeutic strategies for affected children.