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With many different types of leukodystrophies and causes, treatment therapies vary for each type. Many studies and clinical trials are in progress to find treatment and therapies for each of the different leukodystrophies. Stem cell transplants and gene therapy appear to be the most promising in treating all leukodystrophies providing it is done as early as possible.
For hypomyelinating leukodystrophies, therapeutic research into cell-based therapies appears promising. Oligodendrocyte precursor cells and neural stem cells have been transplanted successfully and have shown to be healthy a year later. Fractional anisotropy and radial diffusivity maps showed possible myelination in the region of the transplant. Induced pluripotent stem cells, oligodendrocyte precursor cells, gene correction, and transplantation to promote the maturation, survival, and myelination of oligodendrocytes seem to be the primary routes for possible treatments.
For three types of leukodystrophies (X-linked adrenoleukodystrophy (X-ALD), metachromatic leukodystrophy (MLD) and Krabbe Disease (globoid cell leukodystrophy - GLD), gene therapy using autologous hematopoietic stem cells to transfer the disease gene with lentiviral vectors have shown to be successful and are currently being used in clinical trials for X-ALD and MLD. The progression of X-ALD has shown to be disrupted with hematopoietic stem cell gene therapy but the exact reason why demyelination stops and the amount of stem cells needed is unclear. While there is an accumulation of very long chain fatty acids in the brain, it does not seem to be the reason behind the disease as gene therapy does not correct it.
Adeno-associated vectors have also been used in intracerebral injections to treat MLD. In some patients with MLD, their IQ increased, nerve conduction improved, their MRIs appeared stable, and had normal enzyme levels. Although the greater majority of patients seem to improve after the transplant, some do not respond well to treatment, which may cause devastating outcomes. For those leukodystrophies that result from a deficiency of lysozyme enzymes, such as Krabbes disease, enzyme replacement therapy seems hopeful, however, this proves difficult as the blood-brain barrier severely limits what can pass through into the central nervous system. Due to this obstacle, most research and clinical trials are turning to allogeneic hematopoietic stem cell transplantation.
Currently Sandhoff disease does not have any standard treatment and does not have a cure. However, a person suffering from the disease needs proper nutrition, hydration, and maintenance of clear airways. To reduce some symptoms that may occur with Sandhoff disease, the patient may take anticonvulsants to manage seizures or medications to treat respiratory infections, and consume a precise diet consisting of puree foods due to difficulties swallowing. Infants with the disease usually die by the age of 3 due to respiratory infections. The patient must be under constant surveillance because they can suffer from aspiration or lack the ability to change from the passageway to their lungs versus their stomach and their spit travels to the lungs causing bronchopneumonia. The patient also lacks the ability to cough and therefore must undergo a treatment to shake up their body to remove the mucus from the lining of their lungs. Medication is also given to patients to lessen their symptoms including seizures.
Currently the government is testing several treatments including N-butyl-deoxynojirimycin in mice, as well as stem cell treatment in humans and other medical treatments recruiting test patients.
No cures for lysosomal storage diseases are known, and treatment is mostly symptomatic, although bone marrow transplantation and enzyme replacement therapy (ERT) have been tried with some success. ERT can minimize symptoms and prevent permanent damage to the body. In addition, umbilical cord blood transplantation is being performed at specialized centers for a number of these diseases. In addition, substrate reduction therapy, a method used to decrease the production of storage material, is currently being evaluated for some of these diseases. Furthermore, chaperone therapy, a technique used to stabilize the defective enzymes produced by patients, is being examined for certain of these disorders. The experimental technique of gene therapy may offer cures in the future.
Ambroxol has recently been shown to increase activity of the lysosomal enzyme glucocerebrosidase, so it may be a useful therapeutic agent for both Gaucher disease and Parkinson's disease. Ambroxol triggers the secretion of lysosomes from cells by inducing a pH-dependent calcium release from acidic calcium stores. Hence, relieving the cell from accumulating degradation products is a proposed mechanism by which this drug may help.
In 2014 the European Medicines Agency (EMA) granted orphan drug designation to arimoclomol for the treatment of Niemann-Pick type C. This was followed in 2015 by the U.S. Food & Drug Administration (FDA). Dosing in a placebo-controlled phase II/III clinical trial to investigate treatment for Niemann-Pick type C (for patients with both type C1 and C2) using arimoclomol began in 2016. Arimoclomol, which is orally administered, induces the heat shock response in cells and is well tolerated in humans.
For those with type-I and most type-III, enzyme replacement treatment with intravenous recombinant glucocerebrosidase can decrease liver and spleen size, reduce skeletal abnormalities, and reverse other manifestations. This treatment costs about US$200,000 annually for a single person and should be continued for life. The rarity of the disease means dose-finding studies have been difficult to conduct, so controversy remains over the optimal dose and dosing frequency. Due to the low incidence, this has become an orphan drug in many countries, meaning a government recognizes and accommodates the financial constraints that limit research into drugs that address a small population.
The first drug for Gaucher's was alglucerase (Ceredase), which was a version of glucocerebrosidase that was harvested from human placental tissue and then modified with enzymes. It was approved by the FDA in 1991 and has been withdrawn from the market due to the approval of similar drugs made with recombinant DNA technology instead of being harvested from tissue; drugs made recombinantly are preferable, since there is no concern about diseases being transmitted from the tissue used in harvesting, there are fewer risks of variations in enzyme structure from batch to batch, and they are less expensive to manufacture.
Available recombinant glucocerebrosidases are:
- Imiglucerase (approved in 1995)
- Velaglucerase (approved in 2010)
- Taliglucerase alfa (Elelyso) (approved in 2012)
- Eliglustat (Cerdelga) (approved in 2014)
Miglustat is a small molecule, orally available drug that was first approved for Gaucher's Disease in Europe in 2002. It works by preventing the formation of glucocerebroside, the substance that builds up and causes harm in Gaucher's. This approach is called substrate reduction therapy.
There is no known cure for Niemann–Pick type C, nor is there any FDA-standard approved disease modifying treatment. Supportive care is essential and substantially improves the quality of life of people affected by NPC. The therapeutic team may include specialists in neurology, pulmonology, gastroenterology, psychiatrist, orthopedics, nutrition, physical therapy and occupational therapy. Standard medications used to treat symptoms can be used in NPC patients. As patients develop difficulty with swallowing, food may need to be softened or thickened, and eventually, parents will need to consider placement of a gastrostomy tube (g-tube, feeding tube).
An observational study is underway at the National Institutes of Health to better characterize the natural history of NPC and to attempt to identify markers of disease progression.
Currently there is no cure for these disorders. Medical care is directed at treating systemic conditions and improving the person's quality of life. Physical therapy and daily exercise may delay joint problems and improve the ability to move.
Changes to the diet will not prevent disease progression, but limiting milk, sugar, and dairy products has helped some individuals experiencing excessive mucus.
Surgery to remove tonsils and adenoids may improve breathing among affected individuals with obstructive airway disorders and sleep apnea. Sleep studies can assess airway status and the possible need for nighttime oxygen. Some patients may require surgical insertion of an endotrachial tube to aid breathing. Surgery can also correct hernias, help drain excessive cerebrospinal fluid from the brain, and free nerves and nerve roots compressed by skeletal and other abnormalities. Corneal transplants may improve vision among patients with significant corneal clouding.
Enzyme replacement therapy (ERT) are currently in use or are being tested. Enzyme replacement therapy has proven useful in reducing non-neurological symptoms and pain. Currently BioMarin Pharmaceutical produces enzyme replacement therapies for MPS type I and VI. Aldurazyme is an enzymatic replacement therapy for alpha-L-iduronidase produced by BioMarin for use in Type I MPS. In July 2006, the United States Food and Drug Administration approved a synthetic version of I2S produced by Shire Pharmaceuticals Group, called Elaprase, as a treatment for MPS type II (Hunter syndrome).
Bone marrow transplantation (BMT) and umbilical cord blood transplantation (UCBT) have had limited success in treating the mucopolysaccharidoses. Abnormal physical characteristics, except for those affecting the skeleton and eyes, may be improved, but neurologic outcomes have varied. BMT and UCBT are high-risk procedures and are usually performed only after family members receive extensive evaluation and counseling.
For information on clinical trials visit Clinical Trials Search
MLD Foundation provides updates on MLD research, including (as of 2017) three clinical trials evaluating gene therapy and enzyme replacement therapy, and various lines of basic research. They are also active in newborn screening.
The Global Leukodystrophy Initiative was formed in 2013 to bring together clinicians, researchers and advocacy groups to focus and improve both clinical care and research.
In addition, many research groups are studying the cellular processes of myelination, which may provide insights into leukodystrophy. Researchers in New York have successfully cured leukodystrophy in mice, using skin cells to repair damaged myelin sheaths. Researchers hypothesize that this treatment may possibly be used in curing human multiple sclerosis.
In terms of beta-mannosidosis treatment there is none currently, individuals that exhibit muscle weakness or seizures are treated based on the symptoms(since there's no cure)
Low-protein food is recommended for this disorder, which requires food products low in particular types of amino acids (e.g., methionine).
Standard of care for treatment of CPT II deficiency commonly involves limitations on prolonged strenuous activity and the following dietary stipulations:
- The medium-chain fatty acid triheptanoin appears to be an effective therapy for adult-onset CPT II deficiency.
- Restriction of lipid intake
- Avoidance of fasting situations
- Dietary modifications including replacement of long-chain with medium-chain triglycerides supplemented with L-carnitine
As with most other fatty acid oxidation disorders, individuals with MCADD need to avoid fasting for prolonged periods of time. During illnesses, they require careful management to stave off metabolic decompensation, which can result in death. Supplementation of simple carbohydrates or glucose during illness is key to prevent catabolism. The duration of fasting for individuals with MCADD varies with age, infants typically require frequent feedings or a slow release source of carbohydrates, such as uncooked cornstarch. Illnesses and other stresses can significantly reduce the fasting tolerance of affected individuals.
Individuals with MCADD should have an "emergency letter" that allows medical staff who are unfamiliar with the patient and the condition to administer correct treatment properly in the event of acute decompensation. This letter should outline the steps needed to intervene in a crisis and have contact information for specialists familiar with the individual's care.
Misdiagnosis issues
- The MCADD disorder is commonly mistaken for Reye Syndrome by pediatricians. Reye Syndrome is a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu.
- Most cases of Reye Syndrome are associated with the use of Aspirin during these viral infections.
No specific cure has been discovered for homocystinuria; however, many people are treated using high doses of vitamin B (also known as pyridoxine). Slightly less than 50% respond to this treatment and need to take supplemental vitamin B for the rest of their lives. Those who do not respond require a Low-sulfur diet (especially monitoring methionine), and most will need treatment with trimethylglycine. A normal dose of folic acid supplement and occasionally adding cysteine to the diet can be helpful, as glutathione is synthesized from cysteine (so adding cysteine can be important to reduce oxidative stress).
Betaine (N,N,N-trimethylglycine) is used to reduce concentrations of homocysteine by promoting the conversion of homocysteine back to methionine, i.e., increasing flux through the re-methylation pathway independent of folate derivatives (which is mainly active in the liver and in the kidneys).The re-formed methionine is then gradually removed by incorporation into body protein. The methionine that is not converted into protein is converted to S-adenosyl-methionine which goes on to form homocysteine again. Betaine is, therefore, only effective if the quantity of methionine to be removed is small. Hence treatment includes both betaine and a diet low in methionine. In classical homocystinuria (CBS, or cystathione beta synthase deficiency), the plasma methionine level usually increases above the normal range of 30 micromoles/L and the concentrations should be monitored as potentially toxic levels (more than 400 micromoles/L) may be reached.
Diagnosis of canine phosphofructokinase deficiency is similar to the blood tests used in diagnosis of humans. Blood tests measuring the total erythrocyte PFK activity are used for definitive diagnosis in most cases. DNA testing for presence of the condition is also available.
Treatment mostly takes the form of supportive care. Owners are advised to keep their dogs out of stressful or exciting situations, avoid high temperature environments and strenuous exercise. It is also important for the owner to be alert for any signs of a hemolytic episode. Dogs carrying the mutated form of the gene should be removed from the breeding population, in order to reduce incidence of the condition.
There are a multiple ways to treat Gunther's diseases, but one of the most crucial things that a person with this disease can do is limit themselves from sun exposure or eliminate sun exposure altogether. There are some sunscreens that have undesirable effects such as tropical sunscreens, but other sunscreens that have zinc oxide and titanium dioxide in them are shown to provide protection due to those light-reflective agents. To block the ultraviolet and visible light wavelengths and get the protection that patients with Gunther's disease require, physical barriers are needed. It is also advised that patients wear protective clothing to block the sun from their skin. Plastic films can be attached to car windows and homes to filter out some of the wavelengths that could cause harm to someone's skin suffering with this disease. Incandescent bulbs replace the normal fluorescent lamps. These bulbs release less light, which prevents the "porphyrin-exciting" wavelengths that fluorescent lights emit.
Other less beneficial treatments have been used to help treat Gunther's disease. These include oral beta-carotene and other treatments such as activated charcoal and cholestyramine, which are used to interrupt and stop the porphyrins from being reabsorbed in the body. The reason that these oral treatments are unreasonable is because they require an extremely large dose of medicine and therefore are not beneficial.
Erythrocyte transfusions have been shown to be a successful measure in decreasing the appearance of the disease by trying to lower the erythropoiesis and circulating porphyrin levels. Unfortunately, having chronic erythrocyte transfusions, it can be extremely harmful to the body and can cause severe complications.
To help with dry eye symptoms and visual function, using topical lubrication can be used.
A more invasive way to help treat Gunther's disease would be to have surgery. There have been numerous studies that have stated that bone marrow transplantation is successful. This is a recently new development for Gunther's disease so the long-term effects are still unresourced. If a patient has a life-threatening infectious complication then bone marrow transplantation is no longer relevant for them.
There are also reports that stem cell transplantation is successful in a limited number of participants
Management for mitochondrial trifunctional protein deficiency entails the following:
- Avoiding factors that might precipitate condition
- Glucose
- Low fat/high carbohydrate nutrition
A diagnosis can be made through a muscle biopsy that shows excess glycogen accumulation. Glycogen deposits in the muscle are a result of the interruption of normal glucose breakdown that regulates the breakdown of glycogen. Blood tests are conducted to measure the activity of phosphofructokinase, which would be lower in a patient with this condition. Patients also commonly display elevated levels of creatine kinase.
Treatment usually entails that the patient refrain from strenuous exercise to prevent muscle pain and cramping. Avoiding carbohydrates is also recommended.
A ketogenic diet also improved the symptoms of an infant with PFK deficiency. The logic behind this treatment is that the low-carb high fat diet forces the body to use fatty acids as a primary energy source instead of glucose. This bypasses the enzymatic defect in glycolysis, lessening the impact of the mutated PFKM enzymes. This has not been widely studied enough to prove if it is a viable treatment, but testing is continuing to explore this option.
Genetic testing to determine whether or not a person is a carrier of the mutated gene is also available.
Sandhoff disease, also known as Sandhoff–Jatzkewitz disease, variant 0 of GM2-Gangliosidosis or Hexosaminidase A and B deficiency, is a lysosomal genetic, lipid storage disorder caused by the inherited deficiency to create functional beta-hexosaminidases A and B. These catabolic enzymes are needed to degrade the neuronal membrane components, ganglioside GM2, its derivative GA2, the glycolipid globoside in visceral tissues, and some oligosaccharides. Accumulation of these metabolites leads to a progressive destruction of the central nervous system and eventually to death. The rare autosomal recessive neurodegenerative disorder is clinically almost indistinguishable from Tay–Sachs disease, another genetic disorder that disrupts beta-hexosaminidases A and S. There are three subsets of Sandhoff disease based on when first symptoms appear: classic infantile, juvenile and adult late onset.
The majority of patients is initially screened by enzyme assay, which is the most efficient method to arrive at a definitive diagnosis. In some families where the disease-causing mutations are known and in certain genetic isolates, mutation analysis may be performed. In addition, after a diagnosis is made by biochemical means, mutation analysis may be performed for certain disorders.
GM2-gangliosidosis, AB variant is a rare, autosomal recessive metabolic disorder that causes progressive destruction of nerve cells in the brain and spinal cord. It has a similar pathology to Sandhoff disease and Tay-Sachs disease. The three diseases are classified together as the GM2 gangliosidoses, because each disease represents a distinct molecular point of failure in the activation of the same enzyme, beta-hexosaminidase. AB variant is caused by a failure in the gene that makes an enzyme cofactor for beta-hexosaminidase, called the GM2 activator.
The treatment of primary immunodeficiencies depends foremost on the nature of the abnormality. Somatic treatment of primarily genetic defects is in its infancy. Most treatment is therefore passive and palliative, and falls into two modalities: managing infections and boosting the immune system.
Reduction of exposure to pathogens may be recommended, and in many situations prophylactic antibiotics or antivirals may be advised.
In the case of humoral immune deficiency, immunoglobulin replacement therapy in the form of intravenous immunoglobulin (IVIG) or subcutaneous immunoglobulin (SCIG) may be available.
In cases of autoimmune disorders, immunosuppression therapies like corticosteroids may be prescribed.
If treatment is initiated early in disease the neurologic sequelae may be reversed and further deterioration can be prevented.
Treatment normally consists of rigorous dieting, involving massive amounts of vitamin E. Vitamin E helps the body restore and produce lipoproteins, which people with abetalipoprotenimia usually lack. Vitamin E also helps keep skin and eyes healthy; studies show that many affected males will have vision problems later on in life. Developmental coordination disorder and muscle weakness are usually treated with physiotherapy or occupational therapy. Dietary restriction of triglycerides has also been useful.
Since PCT is a chronic condition, a comprehensive management of the disease is the most effective means of treatment. Primarily, it is key that patients diagnosed with PCT avoid alcohol consumption, iron supplements, excess exposure to sunlight (especially in the summer), as well as estrogen and chlorinated cyclic hydrocarbons, all of which can potentially exacerbate the disorder. Additionally, the management of excess iron (due to the commonality of hemochromatosis in PCT patients) can be achieved through phlebotomy, whereby blood is systematically drained from the patient. A borderline iron deficiency has been found to have a protective affect by limiting heme synthesis. In the absence of iron, which is to be incorporated in the porphyrin formed in the last step of the synthesis, the mRNA of erythroid 5-aminolevulinate synthase (ALAS-2) is blocked by attachment of an iron-responsive element (IRE) binding cytosolic protein, and transcription of this key enzyme is inhibited.
Low doses of antimalarials can be used. Orally ingested chloroquine is completely absorbed in the gut and is preferentially concentrated in the liver, spleen, and kidneys. They work by removing excess porphyrins from the liver via increasing the excretion rate by forming a coordination complex with the iron center of the porphyrin as well as an intramolecular hydrogen bond between a propionate side chain of the porphyrin and the protonated quinuclidine nitrogen atom of either alkaloid. Due to the presence of the chlorine atom, the entire complex is more water soluble allowing the kidneys to preferentially remove it from the blood stream and expel it through urination. It should be noted that chloroquine treatment can induce porphyria attacks within the first couple of months of treatment due to the mass mobilization of porphyrins from the liver into the blood stream. Complete remission can be seen within 6–12 months as each dose of antimalarial can only remove a finite amount of porphyrins and there are generally decades of accumulation to be cleared. Originally, higher doses were used to treat the condition but are no longer recommended because of liver toxicity. Finally, due to the strong association between PCT and Hepatitis C, the treatment of Hepatitis C (if present) is vital to the effective treatment of PCT.
Chloroquine, hydroxychloroquine, and venesection are typically employed in the management strategy.
There are no effective drugs that inhibit or cure the virus infection without toxicity. Therefore, treatment aims at reversing the immune deficiency to slow or stop the disease progress. In patients on immunosuppression, this means stopping the drugs or using plasma exchange to accelerate the removal of the biologic agent that put the person at risk for PML.
In HIV-infected people, this may mean starting highly active antiretroviral therapy (HAART). AIDS patients starting HAART after being diagnosed with PML tend to have a slightly longer survival time than patients who were already on HAART and then develop PML. Some AIDS patients with PML have been able to survive for several years, with HAART. A rare complication of effective HAART is immune reconstitution inflammatory syndrome (IRIS), in which increased immune system activity actually increases the damage caused by the JCV infection; although IRIS can often be managed with medication, it is extremely dangerous in PML.
Cidofovir was studied as possible treatment for PML and has been used on a case by case basis, working in some, but not others.
Cytarabine (also known as ARA-C), a chemotherapy drug used to treat certain cancers, has been prescribed on an experimental basis for a small number of non-AIDS PML patients and stabilized the neurological condition of a minority of these patients. One patient regained some cognitive function lost as a result of PML.
In June 2010, the first case report appeared of a PML patient being successfully treated with the anti malaria drug mefloquine with activity against the JC virus. The patient cleared the virus and had no further neurological deterioration.
Two case reports of using interleukin-2 successfully have been published. Some success have been reported with mirtazapine, but this has not been demonstrated in clinical trials.
A number of drugs work against JC virus in cell culture, but there is no proven, effective therapy in humans.
For example, 1-O-hexadecyloxypropyl-cidofovir (CMX001), suppresses JCV but has been found to have toxicity at therapeutic dosage. The number of patients treated with other therapies is too low to demonstrate effectiveness.