CTX Awareness Day Date in the current year: September 17, 2026

Сerebrotendinous xanthomatosis (CTX), also known as cerebral cholesterosis, is caused by mutations in the CYP27A1 gene, which encodes an enzyme involved in bile acid production. CTX is an autosomal recessive disorder, meaning a person needs to inherit a copy of the faulty gene from each parent. When both parents are carriers, there is a 25% chance that their child will develop CTX.

Mutations in the CYP27A1 gene disrupt the body’s bile acid balance, leading to the accumulation of a compound called cholestanol in various tissues, which causes a wide range of symptoms. This buildup is gradual, so the average age at which symptoms appear for CTX patients is 19 years old.

Neurological symptoms of CTX, which are caused by the buildup of cholestanol in the central nervous system, are usually the first to appear. The earliest neurological symptoms are usually epilepsy and parkinsonism. Other associated neurological disorders include dystonia, ataxia, palatal myoclonus, intellectual disability, early-onset dementia, depression, hallucinations, and suicidal ideation.

It would probably be more correct to say that childhood cataracts, newborn cholestatic jaundice, and infantile diarrhea are the earliest symptoms of CTX because they may develop before neurological symptoms. However, these symptoms rarely contribute to the diagnosis because they are typically treated as isolated problems without an underlying condition until other symptoms manifest later in life.

Other non-neurological CTX symptoms that develop later in life are quite varied. They include premature atherosclerosis, cardiovascular disease, osteoporosis, chronic and intractable diarrhea, gallstones, and xanthomas, often originating on the Achilles tendons. Not all individuals with CTX develop all signs and symptoms; some are affected more than others.

CTX is a progressive disease which can lead to severe seizures, motor difficulties, and cognitive impairment if left untreated. Yet diagnosis is often significantly delayed: on average, 16 years pass between the onset of symptoms and the diagnosis of CTX because many of the symptoms are nonspecific or are attributed to a more common, isolated condition, while the more distinctive combination of findings develops later in life.

Like many other rare genetic conditions, CTX is incurable because there is no way to address the underlying genetic cause. However, it is treatable. The primary treatment is bile acid replacement therapy, which prevents the accumulation of cholestanol. This is complemented by supportive treatment for specific symptoms, such as parkinsonism, seizures, depression, and dystonia.

CTX Awareness Day was launched by the CTX Alliance, a US-based registered charity that advocates for CTX patients and their caregivers, working to provide education and support, improve diagnosis rates, and promote research. The main goals of the observance are to raise awareness of CTX among medical professionals and the general public, draw attention to the importance of early diagnosis and access to treatment, and support affected families.