Cerebrotendinous Xanthomatosis (CTX) 

Updated: Jun 20, 2019
Author: Robert D Steiner, MD; Chief Editor: Maria Descartes, MD 

Overview

Background

Cerebrotendinous xanthomatosis (CTX) is a rare genetic metabolic disorder of cholesterol and bile acid metabolism that results in systemic and neurologic abnormalities.[1] Typically, the disease begins in infancy with chronic diarrhea. Cataracts become evident in childhood or adolescence, and xanthomata develop in the second and third decades of life. Significant neurologic impairment also occurs; this often includes seizures, dementia, and cerebellar and extrapyramidal dysfunction, typically beginning in the third decade of life and progressing until death, often in the sixth decade of life if the condition goes untreated. The presentation and course widely vary, and treatment can dramatically alter the natural history, especially with early initiation

The disease was first described in 1937 by Van Bogaert and colleagues and has since been characterized clinically, biochemically, and genetically.[2, 3] In 1968, Menkes et al described the accumulation of cholestanol, the primary metabolite found in elevated concentrations in cerebrotendinous xanthomatosis, in tissues of the CNS.[4] In 1971, Salen found that chenodeoxycholic acid (CDCA), an important bile acid, was virtually absent in patients with clinical symptoms of the disease.[5] This led to successful trials of therapy with CDCA replacement, in 1975 by Salen[6] and later with Berginer,[7] that was found to normalize the biochemical phenotype and prevent disease progression. In 1980, defects in mitochondrial sterol 27-hydroxylase were implicated in the biochemical pathophysiology of the disease by Oftebro et al.[8] In 1991, mutations in the gene CYP27A1 were discovered as causative.[9, 10, 11] Since then, more than 50 mutations have been described.

Pathophysiology

The primary enzymatic defect in cerebrotendinous xanthomatosis is in mitochondrial sterol 27-hydroxylase, a key enzyme in the complicated process of bile acid synthesis from cholesterol. Defective enzymatic function disrupts bile acid synthesis. Defects in the enzyme result in decreased synthesis of CDCA; this, in turn, disrupts feedback regulation on cholesterol 7-alpha-hydroxylase, which is the rate-limiting step in bile acid synthesis. Therefore, bile acid precursors accumulate in tissues. Cholestanol is formed in a pathway from the bile acid precursor 7-alpha-hydroxy-4-cholesten-3-one.[12] Deposition of cholestanol and cholesterol in the CNS (the brain and spinal cord), muscle (including the heart), blood vessels, eye, and tendon results in a degenerative process that worsens over time unless treated.

The mechanisms leading to brain involvement have been debated.[13, 14]

Patients with cerebrotendinous xanthomatosis appear to have a diffuse decrease in total brain volume, the decrease being predominantly in cortical grey matter rather than white matter. This finding provides additional evidence that cerebrotendinous xanthomatosis is a primary neuronal disorder.[15]

Epidemiology

Frequency

More than 300 patients have been diagnosed worldwide, with an estimated prevalence of 1 case per 50,000 individuals in white populations.[10, 16] Genetic islands of increased CYP27A1 mutation frequency exist; for example, there is an estimated disease prevalence of 1:440 for the Druze population in Israel.[17]

United States

Given the estimates of incidence, as many as 8,000-14,000 people in the United States may have cerebrotendinous xanthomatosis. These are far more cases than have actually been diagnosed, and experts strongly believe that the condition is seriously underdiagnosed in the United States.

International

Cases have been reported in China, Canada, Belgium, Brazil, Saudi Arabia, India, Germany, Taiwan, France, Switzerland, South Africa, Australia, Israel, and Argentina; a large representation has been reported among Spanish[18] and Scandinavian populations, as well as in Italy and Japan. A nationwide survey in Japan revealed an average 16.5-year diagnostic delay, providing further evidence that cerebrotendinous xanthomatosis may be underdiagnosed.[19] A founder effect and high rate of consanguinity appear to be responsible for a high prevalence among the Druze population.[17, 20]

Mutation analysis internationally reveals the following high frequency alleles: T339M in Dutch patients, R474(Q-W) in Japanese patients, and A216P in Italian patients.[10] A genetic study allows estimation of frequencies across many populations, but confirmation is needed.[21]

Mortality/Morbidity

Life expectancy is lowered; however, no formal epidemiologic studies have been published. Death can be as early as infancy, although it is more common between the fourth and sixth decades of life, with progressive incapacitation usually occurring in the fourth and fifth decades of life. Causes of death reported in the literature include myocardial infarction and progressive mental deterioration with pseudobulbar palsies.[22]

Morbidity begins with intractable diarrhea. Presenile cataracts result in vision abnormalities. Xanthomas can cause motor restriction and joint deformities, resulting in various orthopedic sequelae. Vascular abnormalities such as premature atherosclerosis (especially in the carotid and coronary vessels) can lead to stroke and myocardial infarction. The primary neurologic manifestations of the disease are associated with complications that range from treatable seizures to neurologic devastation. The severity of disease widely varies.

Race

Series of patients have been described in the Netherlands, Italy, Spain and Japan, with scattered case reports around the world (see International). No current data on US prevalence among Hispanics or African Americans are available.

Sex

No sex predilection has been reported for this autosomal recessive disorder, although animal models exhibit sex differences.

Age

Cerebrotendinous xanthomatosis can present at any age, from the neonatal period to the sixth decade of life or later.

Prognosis

If cerebrotendinous xanthomatosis is untreated, life expectancy is into the fifth and sixth decades; however, confirmed deaths have been reported as early as age 4 months. This is a progressive and terminal disease if left untreated. Treated patients may have a normal lifespan.

 

Presentation

History

Typically, untreated cerebrotendinous xanthomatosis (CTX) follows a progressive course. Mignarri et al recently proposed a suspicion index for earlier diagnosis of cerebrotendinous xanthomatosis with weighted scores assigned to indicators of disease.[23] Four clinical criteria are used in diagnosis; the presence of any 2 of the criteria warrants testing for cerebrotendinous xanthomatosis, although because this is a treatable disorder, testing when only 1 criterion is present is reasonable. The criteria include intractable diarrhea, presenile cataracts, tendinous xanthomas, and neurologic abnormalities. The symptoms usually manifest themselves in that order, although atypical cases have been reported and the disease spectrum widely varies, even among families. To date, no genotype-phenotype correlation has been reported.

Common findings

Chronic, sometimes intractable diarrhea occurs, with onset typically in infancy. The diarrhea continues through adulthood if left untreated.[24] Neonatal or infantile hepatitis and prolonged jaundice have been described.[9, 25]

The typical onset of ocular symptoms is in the first decade of life, rarely earlier than age 5 years. The following ocular findings are noted:

  • Bilateral, presenile cataracts that may be corticonuclear, anterior pole, or dense posterior opacities[26, 27, 28, 29]

  • Optic disk pallor

  • Premature retinal senescence with retinal vessel sclerosis

  • Cholesterol-like deposits along vascular arcade

  • Myelinated retinal nerve fibers[30]

  • Rarely, palpebral xanthelasma, proptosis (described once), and optic nerve atrophy

  • Unique bilateral fleck lenticular deposits have been described in affected children prior to development of capsular opacities[31]

Juvenile cataracts may be a presenting sign.[29] Xanthomas are rarely seen before age 20 years, although an exaggerated phenotype may be observed in patients with heterozygous familial hypercholesterolemia and cerebrotendinous xanthomatosis.[32] They are usually found on the Achilles tendon but may also be found on the patella, elbow, hand, and neck tendons. They have also been reported on the parenchyma of the lungs and brain, as well as in the bones. See the images below for examples.

Sixteen-year-old male with cerebrotendinous xantho Sixteen-year-old male with cerebrotendinous xanthomatosis. Note the xanthomas on his knuckles.
Sixteen-year-old male with cerebrotendinous xantho Sixteen-year-old male with cerebrotendinous xanthomatosis.
Xanthomas of the Achilles tendon. Photo courtesy o Xanthomas of the Achilles tendon. Photo courtesy of William Connor, MD, Oregon Health and Science University.
Xanthomas on the knees in a patient with cerebrote Xanthomas on the knees in a patient with cerebrotendinous xanthomatosis. Photo courtesy of William Connor, MD, Oregon Health and Science University.

Neurologic symptoms tend to manifest in the third decade of life; however, children and young adults may have below-average intelligence, occasionally severe mental retardation, with worsening and deterioration in the third decade of life. In one study, neurologic symptoms were broken down into extrapyramidal (81%), low intelligence (66%), and cerebellar signs (56%).[23] Polyneuropathy was present in 31% of patients, and only 16% of patients had seizures, although seizures can be the presenting symptom.[33] The latter is a lower estimate in relation to other reports. Other symptoms include the following:

  • Fronto-temporal dementia[11, 30]

  • Spasticity (both periventricular white matter and isolated spinal cord disease)

  • Cerebellar symptoms and ataxia (with other neurologic signs or isolated)[34]

  • Extrapyramidal symptoms, including dystonia and oromandibular dyskinesia[35]

  • Early-onset Parkinson disease[36]

  • Seizures

  • Peripheral neuropathy

Muscular symptoms may include myopathic facies and generalized feelings of weakness.[37]

Less common findings

Neonatal cholestasis has been observed repeatedly.[38] Cerebrotendinous xanthomatosis has been associated with marked cardiovascular findings, including coronary and carotid vascular disease[22, 39] and atrial septal hypertrophy[40, 41]

Granulomatous bone lesions, osteopenia, osteoporosis, and pathologic fractures have been well described. The granulomas are typically in the femur and lumbar vertebrae; thoracic kyphosis has been described.[42]

Granulomatous lung disease has been reported based on bronchoalveolar lavage findings.[43] These patients did not have correlating clinical symptoms. Pulmonary xanthomas have also been described.

Although hypothyroidism is not a common manifestation, it appears to be one of the few endocrinologic complications. In one particular series, the proband case had an ectopic thyroid gland and typical neurologic changes associated with cerebrotendinous xanthomatosis; 4 patients in this study had cerebrotendinous xanthomatosis and hypothyroidism.[44]

A single case report described a case of "minimal change" nephrotic syndrome and cerebrotendinous xanthomatosis in a Japanese adult.[45]

Osteoporosis, tooth loss, cataracts, dementia and parkinsonism, and heart disease can mimic signs of aging at an earlier age.[46]

Physical

See History.

Causes

Cerebrotendinous xanthomatosis is a defect in bile acid synthesis, with subsequent overproduction and accumulation of cholestanol in multiple tissues of the body. It is caused by a defect in the CYP27A1 gene that codes for sterol 27-hydoxylase. The gene is located at 2q33-qter. It is an autosomal recessive disorder.

A recent review and update by Gallus et al identified mutations in exons 1-8 of the CYP27A1 gene but none in exon 9.[10] More than 50 mutations have been identified. Half of these are found in exons 6-8, and many have effects on enzyme heme-binding and adrenodoxin-binding sites. In one study, mutation analysis revealed mutations of all types, including missense (45%), nonsense (20%), splice site (18%), deletion (14%), and insertion (2%).[10]

Typically, affected individuals have mutations in both alleles; although sometimes homozygous, a substantial number of compound heterozygote patients have been described. Two heterozygous patients with clinical disease and decreased enzyme function have been reported, but no second mutation was identified despite an extensive search.[11, 47]

CYP27A1 was recently identified as a candidate gene for sporadic amyotrophic lateral sclerosis (ALS).[48] This is of interest as cerebrotendinous xanthomatosis can present as a clinical mimic of ALS with progressive upper motor neuron loss.

 

DDx

Differential Diagnoses

 

Workup

Laboratory Studies

Laboratory studies in cerebrotendinous xanthomatosis (CTX) include various tests.

Whole blood, serum, and plasma studies

Findings reveal elevated plasma and serum cholestanol levels and low-to-normal cholesterol levels (usually 115-220 mg/dL). The cholestanol level is typically 3-15 times higher than mean levels in unaffected individuals and can range from 1.3-15 mg/dL.[22] The cholesterol-to-cholestanol ratio is said to be a better indicator of disease than cholestanol concentration alone.[49] A low cholesterol-to-cholestanol ratio in the diagnostic range is diagnostic in the appropriate clinical setting; however, additional confirmatory testing is recommended if feasible.

Low-density lipoprotein and triglyceride levels are also usually normal. High-density lipoprotein and very-low density lipoprotein levels vary. Although not typically obtained, bile acid intermediate and other sterol levels are also elevated, such as 7-dehydrocholesterol,[50] 7-alpha-hydroxycholesterol, and lathosterol levels. Some serum bile acid levels themselves are low. Measurement of 7-alpha-hydroxy-4-cholesten-3-one facilitates rapid, convenient diagnostic testing for cerebrotendinous xanthomatosis and may or may not be useful in monitoring treatment response.[51, 52] Measurement of the bile acid precursor (7-alpha, 12-alpha-dihydroxy-4-cholesten-3-one) enables sensitive dried bloodspot testing for cerebrotendinous xanthomatosis, possibly even newborn dried bloodspot testing.[53]

Regardless of whether cerebrotendinous xanthomatosis is suspected clinically, it is increasingly being identified by exome or genome sequencing.[54]

Urine studies

Urine testing of bile alcohols (typically pentols) using fast ion bombardment–mass spectroscopy has been performed after a positive serum cholestanol result.[55, 56] Current studies are exploring the use of tandem mass spectrometry as an efficient and affordable way to screen infants; however, no newborn screening has been implemented.[53, 57]

Bile analysis

A large amount of cholestanol is present in the bile of affected individuals (4-11% vs < 1% in controls).[58, 59] As expected, a low concentration of chenodeoxycholic acid (CDCA) is observed along with high concentrations of bile alcohols (conjugated with glucuronic acid).

Cerebrospinal fluid (CSF) studies

Salen et al have reported an increased cholesterol-to-cholestanol ratio (1.5-20 times the reference range); however, this is not routinely analyzed for diagnostic purposes.[60]

Mutation studies

Once disease has been biochemically confirmed, mutation analysis is recommended.

Electrophysiology studies

Decreased nerve conduction velocities as well as somatosensory, motor, brainstem, and visual evoked potentials all relate to peripheral neuropathy.[61, 62] These often correct with CDCA therapy.

Imaging Studies

The brains of individuals with cerebrotendinous xanthomatosis often show both supratentorial and infratentorial abnormalities on MRI. The findings on MRI and CT scanning include cortical and cerebellar atrophy of the brain, as well as focal lesions (including demyelinating lesions and, rarely, xanthomata) in the cerebellum, basal ganglia, and cerebrum. Typical patterns on brain MRI include bilateral lesions consistent with a metabolic abnormality. T2/FLAIR hyperintensity of the subcortical, periventricular, cerebellar white matter, brainstem, and dentate nuclei are characteristic of cerebrotendinous xanthomatosis.[63, 64] T2 abnormalities are also found in the globus pallidus, substantia nigra, and inferior olives with extension into the surrounding white matter in later years of the disease. Some hypointensity in the dentate nuclei was related to hemosiderin and calcification and was found on autopsy. Cerebrotendinous xanthomatosis should be considered in the differential diagnosis of leukodystrophies.[65]

A reasonably large 2017 study showed T1/FLAIR hypointensity consistent with cerebellar vacuolation and T1/FLAIR/SW hypointense alterations compatible with calcification in a subgroup of patients with cerebrotendinous xanthomatosis. Long-term follow-up showed that clinical and neuroradiological stability or progression were almost invariably associated. In patients with cerebellar vacuolation at baseline, worsening over time was observed, while patients lacking vacuoles were clinically and neuroradiologically stable at follow-up. Infratentorial abnormalities on MRI are related to clinical disability. The presence of cerebellar vacuolation may be regarded as a useful biomarker of disease progression and unsatisfactory response to therapy. Conversely, the absence of dentate nuclei signal alteration should be considered an indicator of better prognosis.[64]

Brain MRI fluid attenuation inversion recovery (FLAIR) sequences in one patient revealed cortical and subcortical hyperintensities in the temporal lobes) and globus pallidus. T2-weighted MRI revealed cerebellar hyperintensities within the dentate nucleus. Hypointensities were seen on T1-weighted and susceptibility MRI scans within the cerebellum at the level of the midbrain.[63]

Magnetic resonance spectroscopy reveals diffuse mitochondrial dysfunction and axonal damage, with large amounts of lactate and decreased N -acetylaspartate in the periventricular white matter and cerebellar hemispheres.[63]

Diffusion tensor imaging (DTI) may show abnormalities despite normal conventional brain MRI findings. DTI showed reduced fractional anisotropy (FA) and tract-density in the cerebellum and widespread cerebral reductions of FA. DTI after therapy initiation showed progressive increases in cerebellar tract density and cerebral FA.[66]

Isolated spinal cord white matter disease has been described.[67, 68] MRI may reveal increased intensity in the lateral and dorsal columns, even in mainly cerebral forms of the disease.[63] Magnetization transfer imaging has been found to be a reliable quantitative indicator of the extent of damage in the brain parenchyma.[68] MRI can also be used to evaluate possible tendon xanthomata outside the central nervous system; enlargement of the tendons is evident in such cases.

Other Tests

Other studies include electrophysiologic testing, prenatal testing (only performed if a family member is affected), and population-wide newborn screening (not yet implemented).[69, 70] Electrophysiological testing may reveal motor or sensorimotor peripheral neuropathy (demyelinating, axonal, or mixed). Somatosensory evoked potentials (SSEPs) are commonly affected. Delayed brainstem auditory evoked potentials are common, and visual evoked potentials are often abnormal.[71]

Histologic Findings

CNS findings

Xanthomas and granulomas are found in multiple areas of the brain, including the cerebellar hemispheres, cerebellar peduncles, and globus pallidus. Further studies have reported more involvement of gray matter and have also described pathognomonic lesions of spindle-shaped lipid crystal clefts, fibrosis, and hemosiderin deposition in the dentate nucleus.[72] Neuropathologic findings described include lipid crystal clefts, neuronal loss, demyelination, reactive astrocytosis, and perivascular macrophages, suggesting the limited reversibility of the disease and poor prognosis if treatment is not started early.

Peripheral nerve findings

“Onion bulbs” have been described; this suggests that the process is chronic and demyelinating. Demyelination, remyelination, and primary axonal degeneration have been reported. Whether or not the process is a primary neuroaxonal process is unclear.

Muscular findings

Atrophy and pyknotic nuclei have been reported. Mitochondrial dysfunction has also been noted, as revealed by decreased respiratory chain activity and increased levels of pyruvate and lactate in the serum and cerebrospinal fluid.[37]

Liver findings

Typical findings include amorphous pigment and crystalloid forms associated with smooth endoplasmic reticulum, with some free-floating in the cytoplasm.[58]

Xanthomas

Birefringent crystals are surrounded by giant cells with foamy cytoplasm.

 

Treatment

Medical Care

Early diagnosis of cerebrotendinous xanthomatosis (CTX) is imperative because it is a treatable disease. This early diagnosis depends on recognition of early signs and symptoms, specifically the combination of diarrhea and cataracts along with personal or family history of infantile hepatitis, prolonged jaundice, or early infantile death.

Surgical Care

Cataract repair may be indicated. Surgical xanthoma removal is not recommended. Liver transplantation has been reported in patients with end-stage liver disease, although details are not available at the time of this writing.[73]

Consultations

Consultation with the following may be indicated:

  • Gastroenterologist

  • Ophthalmologist

  • Metabolic and genetic disease specialist

  • Developmental specialist

  • Neurologist

  • Orthopedist

  • Cardiologist

  • Lipid disorder specialist

Diet

A diet low in cholestanol containing foods (eg, egg yolk, butter, cheddar cheese) can significantly reduce plasma cholestanol and cholesterol levels; however, true clinical benefit is not seen unless pharmacologic therapy is also started. Dietary restriction is probably not necessary if pharmacologic treatment is commenced (see below).

Prevention

Therapy with chenodeoxycholic acid (CDCA) can halt and reverse symptoms of the illness, including GI and neurologic complications.

Long-Term Monitoring

The annual examination in patients with cerebrotendinous xanthomatosis (CTX) should consist of the following:[7]

  • Neurologic and neuropsychologic evaluation
  • Cholestanol plasma concentration assessment
  • Brain MRI in selected cases
  • Echocardiography when indicated
  • Bone mineral density assessment when indicated
 

Medication

Medication Summary

The treatment of choice in cerebrotendinous xanthomatosis (CTX) is chenodeoxycholic acid (CDCA) replacement therapy. CDCA should be considered the mainstay of therapy. If hypercholesterolemia is not controlled with CDCA treatment alone, 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors may be added. HMG-CoA reductase inhibitors (ie, statins) have well-established efficacy and safety in patients with hypercholesterolemia and have also been used alone and in combination with CDCA to treat cerebrotendinous xanthomatosis.

Dotti et al examined treatment with CDCA, simvastatin, and low-density lipoprotein apheresis in several combinations.[74] Although the established treatments performed well, low-density lipoprotein apheresis was not associated with a clinical benefit and possibly put the patient at risk for treatment complications.

Other medical treatment modalities typically used in the treatment of disorders of bile and cholesterol metabolism, specifically hydrophilic 7 beta-hydroxy bile acids and cholestyramine, have been ineffective.[75]

Bile Acids

Class Summary

The primary treatment is CDCA, which was initially used for treatment of gallstones. In the United States, CDCA is available as Chenodal and is distributed by prescription by Dohmen Life Science Services (1-866-758-7068). The typical adult dose is 750 mg/d or 10-15 mg/kg/d orally divided 3 times daily.[7]

Treatment with CDCA has been found to normalize bile acid metabolism and to slow, halt, and even reverse problems associated with cerebrotendinous xanthomatosis. In several well-documented studies, the bile acids and metabolites in plasma, bile, urine, and cerebrospinal fluid (CSF) concentrations of cholestanol have normalized after as little as 4 months of treatment.[7]

Clinically, neuropsychologic and peripheral neurologic symptoms improve, as do effects on bone mineralization.

In a landmark study, dementia was found to improve in 10 of 12 patients with cerebrotendinous xanthomatosis after initiating treatment with CDCA, with strong improvements in mentation, speech, orientation, and memory.[7] Corresponding improvements were seen in MRI and EEG findings. Xanthoma and cataract development were nonprogressive but have not reversed with CDCA administration. Biochemical changes include reduced serum cholestanol levels and increased CDCA levels.[76] Further studies have confirmed and expanded on these findings.[61]

After significant neurological pathology is established, although pharmacologic treatment is recommended,[77] the effect can be limited.[61] A recent study demonstrated patients who started treatment later had a worse outcome than those who started treatment earlier.[78] A subset of patients continue to deteriorate despite treatment, although, in select cases, even late institution of treatment may lead to clinical improvement.[79, 17, 78]  The effect of treatment on cataract progression is described in one study.[80]

  

Generally, CDCA appears to be safe, although hepatoxicity has been reported in at least one infant. In that case, dose reduction was successful.[81]  

In March 2015, cholic acid (Cholbam) was approved by the FDA for bile acid synthesis disorders caused by a single enzyme defect. Cholic acid has been rarely used an alternative to CDCA to treat children with cerebrotendinous xanthomatosis.[72] Currently, there is insufficient evidence to recommend its routine use in cerebrotendinous xanthomatosis.

Chenodiol (Chenodal)

Primary bile acid synthesized by the liver. Known to reduce biliary cholesterol secretion. Available as an orphan drug in the United States for treatment of cerebrotendinous xanthomatosis. Generally appears to be safe, although hepatoxicity has been reported in at least one infant. In that case, dose reduction was successful.

 

Questions & Answers

Overview

What is cerebrotendinous xanthomatosis (CTX)?

What is the pathophysiology of cerebrotendinous xanthomatosis (CTX)?

What is the prevalence of cerebrotendinous xanthomatosis (CTX) in white populations?

What is the prevalence of cerebrotendinous xanthomatosis (CTX) in the US?

What is the global prevalence of cerebrotendinous xanthomatosis (CTX)?

What is the mortality associated with cerebrotendinous xanthomatosis (CTX)?

What is the morbidity associated with cerebrotendinous xanthomatosis (CTX)?

What are the racial predilections of cerebrotendinous xanthomatosis (CTX)?

What is the sexual predilection of cerebrotendinous xanthomatosis (CTX)?

At what age does cerebrotendinous xanthomatosis (CTX) typically present?

What is the prognosis of cerebrotendinous xanthomatosis (CTX)?

Presentation

How is cerebrotendinous xanthomatosis (CTX) diagnosed?

What are the signs and symptoms of cerebrotendinous xanthomatosis (CTX)?

What are the neurologic signs and symptoms of cerebrotendinous xanthomatosis (CTX)?

What are the muscular signs and symptoms of cerebrotendinous xanthomatosis (CTX)?

What are the less common manifestations of cerebrotendinous xanthomatosis (CTX)?

What causes cerebrotendinous xanthomatosis (CTX)?

DDX

What are the differential diagnoses for Cerebrotendinous Xanthomatosis (CTX)?

Workup

What is the role of lab tests in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of urine testing in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of bile analysis in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of CSF analysis in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of genetic tests in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of EMG in the workup of cerebrotendinous xanthomatosis (CTX)?

What is the role of imaging studies in the workup of cerebrotendinous xanthomatosis (CTX)?

Which studies may be helpful in the workup of cerebrotendinous xanthomatosis (CTX)?

Which CNS findings are characteristic of cerebrotendinous xanthomatosis (CTX)?

Which peripheral nerve findings are characteristic of cerebrotendinous xanthomatosis (CTX)?

Which muscular findings are characteristic of cerebrotendinous xanthomatosis (CTX)?

Which histologic findings of the liver are characteristic of cerebrotendinous xanthomatosis (CTX)?

Which histologic xanthoma findings are characteristic of cerebrotendinous xanthomatosis (CTX)

Treatment

How is cerebrotendinous xanthomatosis (CTX) treated?

What is the role of surgery in the treatment of cerebrotendinous xanthomatosis (CTX)?

Which specialist consultations are beneficial to patients with cerebrotendinous xanthomatosis (CTX)?

Which dietary modifications are used in the treatment of cerebrotendinous xanthomatosis (CTX)?

What is the role of chenodeoxycholic acid (CDCA) in the treatment of cerebrotendinous xanthomatosis (CTX)?

What is included in the long-term monitoring of cerebrotendinous xanthomatosis (CTX)?

Medications

What is the role of medications in the treatment of cerebrotendinous xanthomatosis (CTX)?

Which medications in the drug class Bile Acids are used in the treatment of Cerebrotendinous Xanthomatosis (CTX)?