Mitochondrial disease: mimics and chameleons
Mika H Martikainen1, Patrick F Chinnery1
1Wellcome Trust Centre for Mitochondrial Research, Newcastle University, Newcastle upon Tyne, UK Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.
Practical Neurology
|July 24, 2015
Summary
Mitochondrial diseases present diverse symptoms, often mimicking common illnesses, posing diagnostic challenges. Identifying these rare inherited disorders requires recognizing subtle clinical clues and utilizing advanced genetic sequencing for accurate diagnosis.
Area of Science:
- Genetics and Molecular Biology
- Neurology
- Metabolic Disorders
Background:
- Mitochondrial diseases are inherited disorders affecting oxidative phosphorylation.
- Clinical presentations are highly variable, with diverse inheritance patterns.
- Symptoms often overlap with common neurological and non-neurological conditions, complicating diagnosis.
Purpose of the Study:
- To review common clinical features of mitochondrial diseases.
- To provide guidance on identifying patients with these disorders.
- To discuss diagnostic challenges, including 'chameleons' and 'mimics'.
Main Methods:
- Review of clinical features associated with mitochondrial disease.
- Discussion of diagnostic challenges and differential diagnoses.
- Consideration of emerging diagnostic technologies like next-generation sequencing.
Main Results:
- Mitochondrial disorders can present with a wide range of symptoms, often resembling more common diseases.
- Diagnostic difficulty arises from symptom overlap and varied inheritance patterns.
- The concept of 'chameleons' (mitochondrial disorders presenting atypically) and 'mimics' (other conditions resembling mitochondrial disease) is highlighted.
Conclusions:
- Accurate diagnosis of mitochondrial diseases requires careful clinical evaluation and recognition of subtle signs.
- Neurologists may encounter and potentially miss mitochondrial disorders in routine practice.
- Next-generation sequencing is expected to simplify the diagnostic approach in the near future.
Keywords:
MITOCHONDRIAL DISORDERS
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