A case of 3243A>G mutation in mtDNA presenting as apparently idiopathic hyperCKemia.
The 3243A>G mutation of mtDNA usually is associated with MELAS syndrome. Here we report a patient with the 3243A>G mutation presenting only recurrent muscle fatigue and elevated levels of serum creatine kinase (CK). The mother of the proband was referred to us for type 2 diabetes mellitus, muscle pain and sensorineural hearing loss. The percentage of mutation load in different tissues was similar in both subjects, except in the urinary epithelium. The mutation load in the son's urinary epithelial cells (UEC) was consistently higher (nearly 50%) than in his muscle (nearly 20%). We conclude that a correlation between the proportion of the UEC mutation load and the severity of the disease was lacking in this pedigree. The use of UEC as the tissue of choice in the noninvasive diagnosis of the 3243A>G mutation offers a very attractive alternative to muscle biopsy. Finally, our data expand the clinical spectrum of the 3243A>G mutation.
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Anna
A
Rubegni
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Elena
E
Cardaioli
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Elena
E
Chini
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Paola
P
Da Pozzo
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Carla
C
Battisti
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy. Electronic address: alessandro.malandrini@unisi.it.
Alessandro
A
Malandrini
Dept. of Medical, Surgical and Neurological Sciences, University of Siena, Viale Bracci 2, 53100 Siena, Italy.
Antonio
A
Federico
D003402:Creatine Kinase / Q000097:blood*; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000235:genetics*; D006801:Humans; D008297:Male; D028361:Mitochondrial Diseases / Q000097:blood / Q000235:genetics* / Q000473:pathology; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology; D009154:Mutation / Q000235:genetics*; D055815:Young Adult
D004272:DNA, Mitochondrial; D003402:Creatine Kinase
3243A>G mutation; Heteroplasmy; Idiopathic hyperCKemia; MELAS syndrome; Mitochondrial myopathy; Mutation load