A novel mutation in TANGO2 gene associated with recurrent muscle weakness with rhabdomyolysis , metabolic encephalopathy and cardiac arrhythmia: a case report

Abstract

Background TANGO2 depletion was found to cause clinically recognizable multi-organ involvement disorder in pediatrics with episodic muscle weakness recurrent rhabdomyolysis, intellectual disability, metabolic encephalomyopathic crises and cardiac arrhythmia. TANGO2 deficiency is also referred to as \"metabolic encephalomyopathic crises, recurrent, with rhabdomyolysis, cardiac arrhythmias, and neurodegeneration\" (MECRCN) in OMIM. * 616830 Case presentation We report a case of a 4-year-old Saudi boy from a consanguineous Saudi family with two uncles deceased at 3 year of age with recurrent muscle weakness and hyperammonemia of unknown cause .Patient in last attack progressed to severe metabolic encephalomyopathic crisis that required assisted ventilation for 4 months, complicated with life threatening cardiac tachyarrhythmia. Laboratory findings of hypoglycemia, mild hyperammonemia , severely elevated plasma Creatine Kinase, myoglobinuria , lactic acidosis and increased TSH concentration indicating hypothyroidism have been documented. The clinical profile was highly suggestive of TANGO2-realted disorder. Direct DNA sequence analysis of the entire coding regions of TANGO2 gene identified a novel homozygous deletion for three nucleotides in exon 2 (c.11_13delTCT) resulting in amino acid deletion (phenylalanine) at position 5. Conclusion This report illustrates the importance of collating clinical data and keeping a high index of suspicion in order to reach to the diagnosis.