MCQs Primary mitochondrial disorder

 

1.All are true regarding Primary Mitochondrial disorder except 

a.caused by variants in mtDNA

b.caused by variants in nDNA 

c.occurence at any age 

d.commonly affects pediatric CNS 

e.affect organ highly dependent on anaerobic metabolism 

1.ANS --e

 Primary mitochondrial disorder (PMD) is caused by pathogenic variants in mitochondrial DNA (mtDNA) or nuclear DNA (nDNA) that commonly affect the pediatric central nervous system (CNS), lacking pathognomonic imaging findings. 

 PMDs are clinically heterogeneous, may occur at any age, and manifest with a broad range of multiple symptoms. They can affect any organ or tissue but usually affect those organs or tissues that are highly dependent on aerobic metabolism and that have high energy requirements, such as the CNS, heart tissue, and skeletal muscle.

Impaired ATP production is the common outcome of all PMDs. It is well known that certain neuronal populations, including large and long projection neurons (particularly those with sparsely myelinated axons) and fast-spiking interneurons, are especially dependent on oxidative metabolism and extremely susceptible to respiratory chain impairment

2.Common CNS Primary mitochondrial disorders are all except

a. Leigh syndrome

b. Sturge-Weber syndrome  

c.MELAS, 

d.Kearns-Sayre syndrome,

e. Leber hereditary optic neuropathy (LHON)

2.ANS ---b

 Common CNS PMDs with characteristic imaging phenotypes include ----

Leigh syndrome

POLG-RDs

 MELAS

 Kearns-Sayre syndrome

Leber hereditary optic neuropathy (LHON)

pyruvate dehydrogenase (PDH) complex deficiency

coQ10 deficiency

 leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL).

3.The spectrum of MR neuroimaging findings of PMDs includes

a. basal ganglia signal intensity changes

b.basal ganglia calcification

c. callosal dysgenesis ortical 

d.subependymal cysts

e.all

3.ANS---e

The spectrum of MR neuroimaging findings of PMDs includes ---

basal ganglia signal intensity changes

basal ganglia calcification

 cortical signal intensity changes and malformations

 subependymal cysts

 white matter changes (leukoencephalopathy, white matter cavitation, callosal agenesis or dysgenesis, and delayed myelination or hypomyelination).

MRI spectrum of LEIGH syndrome ---