Which organs are most affected by mitochondrial diseases?

Mitochondrial diseases particularly affect organs and tissues that require large amounts of energy to perform their vital functions. These organs include the brain, muscles, heart, kidneys, eyes, and ears [1]. Since mitochondria are responsible for energy production in almost all body cells, any dysfunction in them can lead to a lack of cellular energy and the accumulation of unused oxygen and fuel molecules, causing cell damage [1].

Why are some organs more affected than others?

Nerve and muscle cells, in particular, have very high energy needs; therefore, muscle and neurological problems are common symptoms of mitochondrial diseases [2]. Symptoms can range from mild to severe and may affect only one organ or multiple organs in the body [1]. The extent of the disease's impact depends on the number of defective mitochondria and their location in the body [1].

Organs and the Nervous System

Neurological problems are very common in mitochondrial diseases, as they can affect the brain, spinal cord, and peripheral nerves. Symptoms associated with the nervous system include migraines, seizures, difficulties with balance and coordination (ataxia), and developmental delays [2]. In some cases, mitochondrial diseases may lead to conditions such as Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-like episodes (MELAS), which can cause progressive brain damage [2].

Effects on Muscles and Heart

Mitochondrial diseases that primarily affect muscles are known as mitochondrial myopathies. The main symptoms of these myopathies include muscle weakness, fatigue, and exercise intolerance [2]. This weakness can lead to drooping eyelids (ptosis) and difficulty moving the eyes (chronic progressive external ophthalmoplegia) [2]. As for the heart, it may be affected by heart rhythm disorders (arrhythmias) or weakness and enlargement of the heart muscle (cardiomyopathy) [2].

Other Organs at Risk

In addition to the brain, muscles, and heart, other organs can be significantly affected. These include the kidneys, where kidney function issues may appear, and the eyes, leading to vision impairment or loss due to damage to the optic nerve or retina [2]. Hearing loss may also occur due to damage to the inner ear or auditory nerve [2]. Some individuals may also suffer from gastrointestinal problems such as vomiting, chronic diarrhea, and abdominal pain [2]. For more information about these disorders, you can visit Mitochondrial Diseases: Understanding Genetic Disorders Affecting Cellular Energy (Arabic).

Monitoring Conditions

Given the variety of organs that can be affected by mitochondrial diseases, regular health check-ups are recommended to identify and monitor any potential problems [2]. Although there is currently no cure for these diseases, available treatments can help alleviate symptoms and slow the progression of the disease [1]. These treatments may include physical therapy, vitamins and dietary supplements, special diets, and medications [1].

Medical references

• Mitochondrial Diseases
• Mitochondrial Disorders