Síndrome De Leigh: A Propósito De Um Caso Clínico Com Mutação No Dna Mitocondrial

Abstract

Objective: Leigh syndrome is a neurodegenerative disorder with an incidence of 1:40,000 live births. It presents wide clinical, biochemical, and genetic heterogeneity, but with homogenous neuropatoradiological alterations. There is no specific treatment, and the prognosis is reserved. This case report aimed familiarize health professionals with the disease.Case Description: A 16-month-hold girl who was followed in outpatient clinic due to axial hypotonia and delayed psychomotor development. Karyotype, auditory evoked potentials and ophthalmologic evaluation were normal. Evidence of hyperlactacidemia and hypocitrullinemia was detected in the patient. After performing brain magnetic resonance under anesthesia, hypotonia got worse, and the patient was hospitalized after an episode of cyanosis and apnea. The electroencephalogram showed no epileptiform activity. Neuroimaging revealed bilateral lenticular hyperintensity, especially in the putamen and in the left globus pallidus regions. Molecular analysis revealed an 8993T>G (MT-ATP6) mutation in the mitochondrial DNA.Comments: Between 10 and 30% of individuals with Leigh syndrome have mitochondrial DNA mutations. The decompensation after anesthetic intercurrences is typically associated with neurological deterioration and, in this case, increased the diagnosis suspicion. It is important to alert for similar cases and to reduce invasive diagnostic tests if the diagnosis is suspected.

Molecular basis of Leigh syndrome: a current look

“…Considering rates over 60% and lower than 85% it is expected a NARP syndrome phenotype; 85% or more it is expected a MILS phenotype, although variations in these values and phenotypes have been reported. Besides heteroplasmy rates a common finding related to this variant is hypocitrullinemia in amino acids evaluation, which may shorten the investigation as Vilarinho L. et al demonstrated in a report that two out of three families had low levels of citrulline [45] and Lopes T. et al reported in a patient [46]. In addition to MTATP6 are m.9176 T > G and m.9185 T > C, described to be associated with late-onset cases [47].…”

Lip cyanosis as the first symptom of Leigh syndrome associated with mitochondrial complex I deficiency due to a compound heterozygous NDUFS1 mutation: A case report

“…Leigh syndrome (LS), a mitochondrial encephalomyopathy caused by mutations in the mitochondrial DNA (mtDNA) or nuclear DNA (nDNA), is a fatal, progressive neurodegenerative disease. [1][2][3] The estimated incidence rate of LS is 1:40,000 live births. [1,3] Neuropathological characteristics of LS include bilateral symmetrical lesions, particularly in the basal ganglia and brainstem regions.…”

“…[1][2][3] The estimated incidence rate of LS is 1:40,000 live births. [1,3] Neuropathological characteristics of LS include bilateral symmetrical lesions, particularly in the basal ganglia and brainstem regions. The clinical features include psychomotor retardation, respiratory difficulties, nystagmus, ophthalmoparesis, optic atrophy, ataxia, and dystonia.…”