Sarcosinemia

At a glance

Autosomal recessive disease characterized by sarcosine dehydrogenase deficiency. Controversies about clinical repercussion exist.

Synonyms

SAR Syndrome; Hypersarcosinemia Syndrome; Complex Deficiency of Sarcosine Dehydrogenase; SARD Deficiency; SARDH Deficiency.

Incidence

1:14,900 to 1:350,000 live births (screening programs).

Genetic inheritance

Autosomal recessive.

Pathophysiology

Caused by mutations in the SARDH gene located on 9q33-q34. Mutation causes deficient activity of sarcosine dehydrogenase and then accumulation of sarcosine, which could explain clinical manifestations.

Diagnosis

Increased concentration of sarcosine in plasma and urine as a result of sarcosine dehydrogenase deficiency. Sarcosine is a key intermediate in 1-carbon metabolism and under normal circumstances is converted to glycine by the enzyme sarcosine dehydrogenase.

Clinical aspects

Usually a benign metabolic state that produces no clinical disease. Multiple symptoms have been reported in sarcosinemia such as mental retardation, growth failure, hepatomegaly, craniostenosis, syndactyly, and cardiomyopathy. There is large number of patients with a high level of sarcosine in plasma who do not present any symptoms. Reported association with clinical symptoms could be as a result of an ascertainment bias.

Precautions before anesthesia

Evaluate cardiac function (clinical, ECG, echocardiography).

Anesthetic considerations

Prophylactic antibiotics should be considered in case of cardiopathy.

Pharmacological implications

There are no known specific implications with this condition.

References