Signs Of Leigh's Disease

October 26, 2023

Leigh's disease is a rare neurological condition usually seen in infants, although it can occasionally show up in older children or adults. It is a progressive disease, meaning it gets worse as time goes on. It is usually fatal a few years after symptoms first appear. The characteristic features of Leigh's disease are cognitive and motor decline. It can be diagnosed through MRIs, which show brain lesions, and genetic testing. A recessive genetic mutation causes Leigh's disease. Diagnostic testing can confirm the problem is Leigh's disease and not another brain condition with similar symptoms. Reveal Leigh's disease symptoms now.

Loss Of Head Control

By the age of six months, infants should have the strength and coordination to hold their heads up. After this age, a loss of head control is extremely concerning. It is also a cause for concern if an infant lacks any control over the head by the age of three or four months. This is one of the most noticeable early symptoms of Leigh's disease. It is an obvious sign there is something wrong with the infant's motor skills. The motor skills will only worsen as the disease progresses. This is because Leigh's disease inhibits energy production in the parts of the brain responsible for motor function.

Learn about another symptom of Leigh's disease associated with loss.

Loss Of Appetite

Another early symptom of Leigh's disease is a loss of appetite. An infant with the condition may show little interest in food. Alternatively, they may have difficulty eating due to a loss of motor skills. The infant may lack the ability to suck, for example. Nausea and vomiting are common at this stage of the disease as well, and this can contribute to the infant's lack of desire to eat. The term 'failure to thrive' may be used to describe an ongoing lack of appetite in an infant. This usually leads to weight loss or failure to gain a normal amount of weight.

Keep reading to get to know more symptoms of Leigh's disease now.

Continuous Crying

Continuous crying is an early sign of Leigh's disease. The illness mainly affects infants, who obviously cannot tell anyone what kind of symptoms they are experiencing. Crying is expected behavior in infants, of course. However, an abnormal amount of crying can signal there is something seriously wrong with the infant's health. It is not normal for an infant to cry excessively after all of their apparent needs have been met. Leigh’s disease causes a lot of discomfort and feelings of weakness, which results in the infant crying a lot. Older children and adults with Leigh's disease are less likely to have this symptom, as they can describe their discomfort with words.

Continue to discover more Leigh's disease symptoms.


Seizures are a serious sign something is wrong with the brain. They are a common early symptom of Leigh's disease. Seizure activity happens because Leigh's disease causes lesions in many parts of the brain, including the cerebral cortex. These lesions cause the neurons in the brain to behave abnormally, which leads to a seizure. A seizure usually lasts for two minutes or less. It can have many different manifestations, which may or may not include convulsions. Regardless of the type of seizure, the child will lose consciousness briefly. Sometimes, the only symptom of a seizure is a very brief loss of awareness; this is called an absence seizure.

Read about more symptoms of Leigh's disease now.

Lack Of Muscle Tone

Lack of muscle tone is also known as hypotonia. It means an individual's body is limp and weak, and the muscles cannot provide adequate resistance. This happens when the brain struggles to tell the muscles to contract. In Leigh's disease, this happens due to brain damage. An infant with a lack of muscle tone will appear to be droopy and have unusually relaxed limbs. For this reason, hypotonia is sometimes given the nickname 'floppy baby syndrome.' The infant may have trouble sitting up or raising their head. They will also tend to have bad reflexes.

MORE FROM HealthPrep