Diagnosis of Glut1 Deficiency Syndrome (Glut1DS)(1) is a treatable neurological disorder, resulting of molecular abnormalities affecting the SLC2A1 gene, which encodes for the glucose transporter type 1 (GLUT1). These genetic alterations can be inherited from one of the parents (variant of autosomal dominant transmission), but some cases of new variants appearing in the patient (de novo) have also been reported.
The pathogenic variants of the SLC2A1 gene lead to functional losses of the glucose receptor at the blood-brain barrier and glial cells.

The classic form of the disease is encephalopathy, characterized in children by pharmacoresistant epilepsy, microcephaly, psychomotor delay, ataxia and abnormal movements.

Atypical forms of milder severity have also been described. The prevalence of Glut1DS is estimated as 1 in 24,000(2), highlighting the importance of early diagnosis for an optimal therapeutic management of patients. Currently, in France, we estimate that more than 90% of affected patients remain undiagnosed(2).

The METAglut1™ test : a simple blood test

This new blood test efficiently identifies affected children and adults (with a sensitivity of 80% and specificity of 99.5%) within 48 hours.

According to a multicenter study conducted in France, the French Health Authority (HAS) recommends using the METAglut1™ test as a first-line diagnostic test.

Unlike the current diagnostic test, which relies on invasive lumbar puncture, the METAglut1™ test is performed on a simple blood sample (whole blood on EDTA).

To reduce the practice of invasive lumbar punctures, the HAS recommends analyzing the SLC2A1 gene or the sequencing a panel of genes, even considering whole exome sequencing, if the clinical suspicion persists despite a negative METAglut1™ test(2).

Since February 22, 2024, the METAglut1™ test for the biological diagnosis of Glucose Transporter Type 1 deficiency syndrome (Glut1DS) is reimbursed by the social security system in France.

In practice, the METAglut1™ test involves the following steps:

METAGLUT1-FLOW CYTOMETRY ANALYSIS

1.   Blood Collection: A blood sample is taken using an EDTA tube.
2.   Storage and Dispatch: The sample is stored and sent to the Cerba laboratory within a maximum of 4 days.
3.   Temperature: The sample should be kept at +4°C.
4.   A medical prescription form is required for the test

1 Syndrome de déficit en transporteur du glucose de type 1, forme classique (ORPHANET : OMIM 606777)
2 Mochel F, Gras D, Luton MP, Nizou M, Giovannini D, Delattre C, Aubart M, Barth M, De Saint-Martin A, Doummar D, Essid N, Garros A, Le Camus CH, Hoebeke C, The Tich SN, Perivier M, Rivera S, Rolland A, Roubertie A, Sarret C, Sevin C, Ville D, Sitbon M, Costa JM, Pons R, Garcia-Cazorla A, Vuillaumier S, Petit V, Boespflug-Tanguy O, De Vivo DC; MetaGlut1 Study Group. Prospective Multicenter Validation of a Simple Blood Test for the Diagnosis of Glut1 Deficiency Syndrome. Neurology. 2023 Jun 6;100(23):e2360-e2373. doi: 10.1212/WNL.0000000000207296. Epub 2023 Apr 19. PMID: 37076312; PMCID: PMC10256121.
3 Évaluation du test METAglut1™ dans le diagnostic de l’encéphalopathie par déficit en transporteur de glucose de type 1, Rapport d’évaluation HAS, Avril 27, 2023)

A question ?

Our international medical secretariat is at your disposal on intgb@lab-cerba.com