Sage Journals: Discover world-class research

Abstract

The point mutation in the mitochondrial genome tRNA^Leu (A3243G) is associated with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS). We report a boy presenting with respiratory compromise and hypercarbia owing to severe muscle weakness. Historically, he demonstrated idiopathic growth hormone deficiency, retarded bone age, and exercise avoidance. Owing to severe respiratory compromise out of proportion to expected recovery, a metabolic work-up was performed. Muscle biopsy demonstrated abnormal mitochondria structure and heteroplasmic A3243G mutation. Idiopathic growth hormone deficiency and retarded bone age have not been previously reported in MELAS, and these findings delayed testing for mitochondrial disease. This case demonstrates that isolated muscle weakness in the context of other organ system abnormalities should make the investigator consider MELAS. (J Child Neurol 2006; 21: 77—79).

Get full access to this article

View all access options for this article.

References

Hirano M. , Pavlakis SG : Mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes (MELAS): Current concepts. J Child Neurol 1994;9:4—13.

Goto Y. , Nonaka I. , Horai S. : A mutation in the tRNA (Leu) (UUR) gene associated with the MELAS subgroup of mitochondrial encephalomyopathies. Nature 1990;348:651—653.

Goto Y. , Nonaka I. , Horai S. : A new mtDNA mutation associated with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke like episodes (MELAS). Biochem Biophys Acta 1991;1097:238—240.

Goto Y. , Tojo M. , Tohyama J. , et al: A novel point mutation in the mitochondrial tRNA Leu (UUR) gene in a family with mitochondrial myopathy. Ann Neurol 1992 ;31:672—674.

Hanna MG , Nelson IP , Morgan-Huges JA , Wood NW : MELAS: A new disease associated mitochondrial DNA mutation and evidence for further genetic heterogeneity. J Neurol Neurosurg Psychiatry 1998;65:512—517.

Hanna MG , Vaughan JR , Silburn PA , et al: Two unusual clinical presentations of the mitochondrial DNA A3243G point mutation in adult neurological practice. J Neurol Neurosurg Psychiatry 1997;62:544—546.

Schapira Ahv , Cooper JM , Morgan-Hughes JA , et al: Mitochondrial myopathy with a defect of mitochondrial-protein transport. N Engl J Med 1990;323:37—42.

DiMauro S. , Bonilla E. , Zeviani M. , et al: Mitochondrial myopathies. Ann Neurol 1985; 17:521-538.

Andreu AL , Bruno C. , Shanski S. , et al: Missense mutation in the mtDNA cytochrome bgenein apatientwithmyopathy . Neurology 1998;51:1444—1447.

10.

Cholley F. , Edery P. , Ricquier D. , et al: Mitochondrial respiratory chain deficiency revealed by hypothermia . Neuropediatrics 2001;32:104—106.

11.

Varanasi SS , Francis RM , Berger CE , et al: Mitochondrial DNA deletion associated oxidative stress and severe male osteoporosis. Osteoporos Int 1999;10:143—149.

A Boy With Muscle Weakness,Hypercarbia,and the Mitochondrial DNA A3243G Mutation

Abstract

Get full access to this article

References