[MIM 616 878]

(metabolic encephalopathy-arrhythmia associated to TANGO2 syndrome, MECRCN)

Incidence 1/106. Autosomal recessive transmission of a mutation of the TANGO2 (Transport and Golgi organization 2) gene (22q11.21).

Association of:

-        encephalomyopathy of varying severity presenting as acute metabolic crises (hypoglycemia and lactic acidosis), often triggered by acute illness, with convulsions, coma

-        with rhabdomyolysis (myoglobinuria, elevated CPK), accompanied by a neurological regression the recovery of which is slow and incomplete

-        rhythm (long QT with torsades de pointe during episodes of rhabdomyolysis) and conduction disorders

-        hypothyroidism.

This results in developmental retardation and neurodegeneration, intellectual deficit, pyramidal and cerebellar signs, loss of speech and cerebral atrophy of varying severity. Death during childhood is usual.

Treatment:

-        avoidance of  episodes of catabolism (fever, prolonged fasting) and lipid overload.

-        daily administration of a multivitamin B complex (containing vitamins B5- pantothenic acid- and B9- folic acid-) at the recommended daily doses for the general population appears to have a preventive effect against metabolic crises.

Anesthetic implications:

-        check the thyroid function, ECG and echocardiography;

-        avoid prolonged preoperative fasting; administer an IV electrolytic solution enriched with 5 or 10 % glucose to cover the caloric needs;

       

        theoretical glucose requirements:

-        1-4 years of age: 8-10 mg/kg/min

-        4-5 years of age: 7 mg/kg/min

-        6-7 years of age: 6 mg/kg/min

-        8-9 years of age: 5-6 mg/kg/min

-        > 10 years of age: 3-4 mg/kg/min

-        avoid succinylcholine (risk of rhabdomyolysis);

-        avoid propofol infusion (lipid overload);

-        by analogy, take the same precautions as in long QT syndrome;

-        be prepared to treat acute rhabdomyolysis:

References : 

-        Hoebeke C, Cano A, De Lonlay P, Chabrol B.
Clinical phenotype associated with TANGO2 gene mutation.
Arch Pédiatr 2021 ; 28 : 80-6.

-        Sandkuhler SE, Zhang L, Meisner JK, Ghaloul-Gonzalez L, Beach CM, Harris D, de Lonlay P et al.
B-complex vitamins for patients with TANGO2-deficiency disorder.
J Inherit Metab Dis 2023 ; 46: 161–2.

Updated: September 2023