Proton spectroscopy: a simple and useful tool in the investigation of mitochondrial disease

Espectroscopia de prótons: uma ferramenta simples e útil na investigação de doença mitocondrial

A 38-year-old woman presented to the emergency department with right hemiparesis. Brain computed tomography (CT) and magnetic resonance imaging (MRI) were recommended (Figures 1 and 2). Genetic study confirmed the presence of a point mutation m.3243 A>G of mtDNA, confirming the diagnosis of Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes (MELAS).

Figure 1.
Brain computed tomography during hospital admission (A), 72 hours later (B), and fluid attenuated inversion recovery imaging (C) demonstrating bilateral lesions that do not respect arterial vascular territories. Diffusion-weighted imaging and apparent diffusion coefficient (D–E) demonstrating T2 shine through effect, representing vasogenic rather than cytotoxic edema.

Figure 2.
Magnetic resonance imaging spectroscopy demonstrates elevated lactate peak in cerebrospinal fluid.

MELAS is a rare mitochondrial disorder that can be manifested by stroke-like episodes, epilepsy, hyperlactatemia, myopathy, headaches, deafness, diabetes, and short stature¹. Although not pathognomonic, the lactate peak observed in spectroscopy can be an indication for MELAS diagnosis, which is found to be correlated with the severity of clinical manifestations². Genetic testing confirms the diagnosis³.

References

• ^1.
  El-Hattab AW, Adesina AM, Jones J, Scaglia F. MELAS syndrome: Clinical manifestations, pathogenesis, and treatment options. Mol Genet Metab. 2015 Sep-Oct;116(1-2):4-12. https://doi.org/10.1016/j.ymgme.2015.06.004
  » https://doi.org/https://doi.org/10.1016/j.ymgme.2015.06.004
• ^2.
  Kaufmann P, Shungu DC, Sano MC, Jhung S, Engelstad K, Mitsis E, et al. Cerebral lactic acidosis correlates with neurological impairment in MELAS. Neurology. 2004 Apr;62(8):1297-302. https://doi.org/10.1212/01.wnl.0000120557.83907.a8
  » https://doi.org/https://doi.org/10.1212/01.wnl.0000120557.83907.a8
• ^3.
  Lorenzoni PJ, Werneck LC, Kay CSK, Silvado CES, Scola RH. When should MELAS (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Strokelike episodes) be the diagnosis? Arq Neuro-Psiquiatr. 2015 Nov;73(11):959-67. https://doi.org/10.1590/0004-282X20150154
  » https://doi.org/https://doi.org/10.1590/0004-282X20150154

Publication Dates

• Publication in this collection
  22 Apr 2022
• Date of issue
  May 2022

History

• Received
  16 Oct 2021
• Reviewed
  23 Nov 2021
• Accepted
  28 Nov 2021