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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
The primary treatment method for fatty-acid metabolism disorders is dietary modification. It is essential that the blood-glucose levels remain at adequate levels to prevent the body from moving fat to the liver for energy. This involves snacking on low-fat, high-carbohydrate nutrients every 2–6 hours. However, some adults and children can sleep for 8–10 hours through the night without snacking.
Carnitor - an L-carnitine supplement that has shown to improve the body's metabolism in individuals with low L-carnitine levels. It is only useful for Specific fatty-acid metabolism disease.
Initial attempts at dietary therapy in ALD involved restricting the intake of very-long chain fatty acids (VLCFA). Dietary intake is not the only source for VLCFA in the body, as they are also synthesized endogenously. This dietary restriction did not impact the levels of VLCFA in plasma and other body tissues. After the realization that endogenous synthesis was an important contribution to VLCFA in the body, efforts at dietary therapy shifted to inhibiting these synthetic pathways in the body. The parents of Lorenzo Odone, a boy with ALD, spearheaded efforts to develop a dietary treatment to slow the progression of the disease. They developed a mixture of unsaturated fatty acids (glycerol trioleate and glyceryl trierucate in a 4:1 ratio), known as Lorenzo's oil that inhibits elongation of saturated fatty acids in the body. Supplementation with Lorenzo's oil has been found to normalize the VLCFA concentrations in the body, although its effectiveness at treating the cerebral manifestations of the disease is still controversial and unproven. Trials with Lorenzo's oil have shown that it does not stop the neurological degradation in symptomatic patients, nor does it improve adrenal function.
While dietary therapy has been shown to be effective to normalize the very-long chain fatty acid concentrations in the plasma of individuals with ALD, allogeneic hematopoietic stem cell transplants is the only treatment that can stop demyelination that is the hallmark of the cerebral forms of the disease. In order to be effective, the transplant must be done at an early stage of the disease; if the demyelination has progressed, transplant can worsen the outcome, and increase the rate of decline. While transplants have been shown to be effective at halting the demyelination process in those presenting with the childhood cerebral form of ALD, follow-up of these patients has shown that it does not improve adrenal function.
Management for mitochondrial trifunctional protein deficiency entails the following:
- Avoiding factors that might precipitate condition
- Glucose
- Low fat/high carbohydrate nutrition
Since phytanic acid is not produced in the human body, individuals with Refsum disease are commonly placed on a phytanic acid-restricted diet and avoid the consumption of fats from ruminant animals and certain fish, such as tuna, cod, and haddock. Grass feeding animals and their milk are also avoided. Recent research has shown that CYP4 isoform enzymes could help reduce the over-accumulation of phytanic acid "in vivo". Plasmapheresis is another medical intervention used to treat patients. This involves the filtering of blood to ensure there is no accumulation of phytanic acid.
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 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.
Currently, no cure for Zellweger syndrome is known, nor is a course of treatment made standard. Infections should be guarded against to prevent such complications as pneumonia and respiratory distress. Other treatment is symptomatic and supportive. Patients usually do not survive beyond one year of age.
The malabsorption resulting from lack of bile acid has resulted in elemental formula being suggested, which are low in fat with < 3% of calories derived from long chain triglycerides (LCT). However, reduced very long chain fatty acids (VLCFA) has not been shown to reduce blood VLCFA levels , likely because humans can endogenously produce most VLCFA. Plasma VLCFA levels are decreased when dietary VLCFA is reduced in conjunction with supplementation of Lorenzo’s oil (a 4:1 mixture of glyceryl trioleate and glyceryl trierucate) in X-ALD patients . Since docosahexaenoic acid (DHA) synthesis is impaired [59], DHA supplementation was recommended, but a placebo-controlled study has since showed no clinical efficacy . Due to the defective bile acid synthesis, fat soluble supplements of vitamins, A, D, E, and K are recommended.
Currently, there is no cure for infantile Refsum disease syndrome, nor is there a standard course of treatment. Infections should be guarded against to prevent such complications as pneumonia and respiratory distress. Other treatment is symptomatic and supportive. Patients show variable lifespans with some individuals surviving until adulthood and into old age.
The most common method to manage hypoglycemia and diabetes is with an insulin pump. . However in infants and very young children long acting insulins like Glargine and Levemir are preferred to prevent recurrent hypoglycemia . As soon as parent knows Walcott-Rallison syndrome is the source, treatment or therapy plans need to be drawn up along with frequent check ins to make sure kidney and liver functions are around normal and insulin therapy are working. If needed, the patient can undergo thyroxin therapy in order to maintain proper thyroid stimulating hormone levels. This has only been needed in a few cases were hypothyroidism was present in the patient.
In ruminant animals, the gut fermentation of consumed plant materials liberates phytol, a constituent of chlorophyll, which is then converted to phytanic acid and stored in fats. Although humans cannot derive significant amounts of phytanic acid from the consumption of chlorophyll present in plant materials, it has been proposed that the great apes (bonobos, chimpanzees, gorillas, and orangutans) can derive significant amounts of phytanic acid from the hindgut fermentation of plant materials.
A diet with carefully controlled levels of the amino acids leucine, isoleucine, and valine must be maintained at all times in order to prevent neurological damage. Since these three amino acids occur in all natural protein, and most natural foods contain some protein, any food intake must be closely monitored, and day-to-day protein intake calculated on a cumulative basis, to ensure individual tolerance levels are not exceeded at any time. As the MSUD diet is so protein-restricted, and adequate protein is a requirement for all humans, tailored metabolic formula containing all the other essential amino acids, as well as any vitamins, minerals, omega-3 fatty acids and trace elements (which may be lacking due to the limited range of permissible foods), are an essential aspect of MSUD management. These complement the MSUD patient's natural food intake to meet normal nutritional requirements without causing harm. If adequate calories cannot be obtained from natural food without exceeding protein tolerance, specialised low protein products such as starch-based baking mixtures, imitation rice and pasta may be prescribed, often alongside a protein-free carbohydrate powder added to food and/or drink, and increased at times of metabolic stress. Some patients with MSUD may also improve with administration of high doses of thiamine, a cofactor of the enzyme that causes the condition.
Usually MSUD patients are monitored by a dietitian. Liver transplantation is another treatment option that can completely and permanently normalise metabolic function, enabling discontinuation of nutritional supplements and strict monitoring of biochemistry and caloric intake, relaxation of MSUD-related lifestyle precautions, and an unrestricted diet. This procedure is most successful when performed at a young age, and weaning from immunosuppressants may even be possible in the long run. However, the surgery is a major undertaking requiring extensive hospitalisation and rigorous adherence to a tapering regime of medications. Following transplant, the risk of periodic rejection will always exist, as will the need for some degree of lifelong monitoring in this respect. Despite normalising clinical presentation, liver transplantation is not considered a cure for MSUD. The patient will still carry two copies of the mutated BKAD gene in each of their own cells, which will consequently still be unable to produce the missing enzyme. They will also still pass one mutated copy of the gene on to each of their biological children. As a major surgery the transplant procedure itself also carries standard risks, although the odds of its success are greatly elevated when the only indication for it is an inborn error of metabolism. In absence of a liver transplant, the MSUD diet must be adhered to strictly and permanently. However, in both treatment scenarios, with proper management, those afflicted are able to live healthy, normal lives without suffering the severe neurological damage associated with the disease.
Currently this sub-type of muscular dystrophy has no cure and no "definitive" treatment exists. Treatment offers preventative tactics to delay muscle breakdown and increase life expectancy. Stretching and physical therapy can increase mobility. Treatment also includes correcting skeletal abnormalities through orthopedic surgery and other orthopedic techniques. Antiepileptic medication is administered to help prevent seizures. ACE inhibitors and beta blockers help treat heart conditions, and respiratory assistance is more than likely needed at some point for the affected individual
The first suspicion of SPCD in a patient with a non-specific presentation is an extremely low plasma carnitine level. When combined with an increased concentration of carnitine in urine, the suspicion of SPCD can often be confirmed by either molecular testing or functional studies assessing the uptake of carnitine in cultured fibroblasts.
Identification of patients presymptomatically via newborn screening has allowed early intervention and treatment. Treatment for SPCD involves high dose carnitine supplementation, which must be continued for life. Individuals who are identified and treated at birth have very good outcomes, including the prevention of cardiomyopathy. Mothers who are identified after a positive newborn screen but are otherwise asymptomatic are typically offered carnitine supplementation as well. The long-term outcomes for asymptomatic adults with SPCD is not known, but the discovery of mothers with undiagnosed cardiomyopathy and SPCD has raised the possibility that identification and treatment may prevent adult onset manifestations.
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.
D-Bifunctional protein deficiency (officially called 17β-hydroxysteroid dehydrogenase IV deficiency) is an autosomal recessive peroxisomal fatty acid oxidation disorder. Peroxisomal disorders are usually caused by a combination of peroxisomal assembly defects or by deficiencies of specific peroxisomal enzymes. The peroxisome is an organelle in the cell similar to the lysosome that functions to detoxify the cell. Peroxisomes contain many different enzymes, such as catalase, and their main function is to neutralize free radicals and detoxify drugs, such as alcohol. For this reason peroxisomes are ubiquitous in the liver and kidney. D-BP deficiency is the most severe peroxisomal disorder, often resembling Zellweger syndrome.
Characteristics of the disorder include neonatal hypotonia and seizures, occurring mostly within the first month of life, as well as visual and hearing impairment. Other symptoms include severe craniofacial disfiguration, psychomotor delay, and neuronal migration defects. Most onsets of the disorder begin in the gestational weeks of development and most affected individuals die within the first two years of life.
The most commonly effective treatment is clonazepam, which leads to the increased efficacy of another inhibitory neurotransmitter, GABA. There are anecdotal reports of the use of Levetiracetam in genetic and acquired hyperekplexia. During attacks of hypertonia and apnea, the limbs and head may be flexed towards the trunk in order to dissipate the symptoms. This is named the Vigevano maneuver after the doctor who invented it.
Malonyl-CoA decarboxylase deficiency (MCD), or Malonic aciduria is an autosomal-recessive metabolic disorder caused by a genetic mutation that disrupts the activity of Malonyl-Coa decarboxylase. This enzyme breaks down Malonyl-CoA (a fatty acid precursor and a fatty acid oxidation blocker) into Acetyl-CoA and carbon dioxide.
Carnitine palmitoyltransferase II deficiency (CPT-II) is an autosomal recessively inherited genetic metabolic disorder characterized by an enzymatic defect that prevents long-chain fatty acids from being transported into the mitochondria for utilization as an energy source.
The adult myopathic form of this disease was first characterized in 1973 by DiMauro and DiMauro. It is the most common inherited disorder of lipid metabolism affecting the skeletal muscle of adults. CPT II deficiency is also the most frequent cause of hereditary myoglobinuria. Symptoms of this disease are commonly provoked by prolonged exercise or periods without food.
A 1994 study of the entire population of New South Wales (Australia) found 20 patients. Of these, 5 (25%) had died at or before 30 months of age. Of the survivors, 1 (5%) was severely disabled and the remainder had either suffered mild disability or were making normal progress in school. A 2006 Dutch study followed 155 cases and found that 27 individuals (17%) had died at an early age. Of the survivors, 24 (19%) suffered from some degree of disability, of which most were mild. All the 18 patients diagnosed neonatally were alive at the time of the follow-up.
For treatment of type II, dietary modification is the initial approach, but many patients require treatment with statins (HMG-CoA reductase inhibitors) to reduce cardiovascular risk. If the triglyceride level is markedly raised, fibrates (peroxisome proliferator-activated receptor-alpha agonists) may be preferable due to their beneficial effects. Combination treatment of statins and fibrates, while highly effective, causes a markedly increased risk of myopathy and rhabdomyolysis, so is only done under close supervision. Other agents commonly added to statins are ezetimibe, niacin, and bile acid sequestrants. Dietary supplementation with fish oil is also used to reduce elevated triglycerides, with the greatest effect occurring in patients with the greatest severity. Some evidence exists for benefit of plant sterol-containing products and omega-3 fatty acids.