Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Branched-chain ketoacid dehydrogenase deficiency results in complex and volatile metabolic derangements that threaten brain development. Treatment for classical maple syrup urine disease (MSUD) should address this underlying physiology while also protecting children from nutrient deficiencies. Based on a 20-year experience managing 79 patients, we designed a study formula to (1) optimize transport of seven amino acids (Tyr, Trp, His, Met, Thr, Gln, Phe) that compete with branched-chain amino acids (BCAAs) for entry into the brain via a common transporter (LAT1), (2) compensate for episodic depletions of glutamine, glutamate, and alanine caused by reverse transamination, and (3) correct deficiencies of omega-3 essential fatty acids, zinc, and selenium widespread among MSUD patients. The formula was enriched with LAT1 amino acid substrates, glutamine, alanine, zinc, selenium, and alpha-linolenic acid (18:3n-3). Fifteen Old Order Mennonite children were started on study formula between birth and 34 months of age and seen at least monthly in the office. Amino acid levels were checked once weekly and more often during illnesses. All children grew and developed normally over a period of 14-33 months. Energy demand, leucine tolerance, and protein accretion were tightly linked during periods of normal growth. Rapid shifts to net protein degradation occurred during illnesses. At baseline, most LAT1 substrates varied inversely with plasma leucine, and their calculated rates of brain uptake were 20-68% below normal. Treatment with study formula increased plasma concentrations of LAT1 substrates and normalized their calculated uptakes into the nervous system. Red cell membrane omega-3 polyunsaturated fatty acids and serum zinc and selenium levels increased on study formula. However, selenium and docosahexaenoic acid (22:6n-3) levels remained below normal. During the study period, hospitalizations decreased from 0.35 to 0.14 per patient per year. There were 28 hospitalizations managed with MSUD hyperalimentation solution; 86% were precipitated by common infections, especially vomiting and gastroenteritis. The large majority of catabolic illnesses were managed successfully at home using 'sick-day' formula and frequent amino acid monitoring. We conclude that the study formula is safe and effective for the treatment of classical MSUD. In principle, dietary enrichment protects the brain against deficiency of amino acids used for protein accretion, neurotransmitter synthesis, and methyl group transfer. Although the pathophysiology of MSUD can be addressed through rational formula design, this does not replace the need for vigilant clinical monitoring, frequent measurement of the complete amino acid profile, and ongoing dietary adjustments that match nutritional intake to the metabolic demands of growth and illness.
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PMID:Classical maple syrup urine disease and brain development: principles of management and formula design. 2006 Nov 71

Maple syrup urine disease (MSUD) is an autosomal recessive disorder associated with impaired metabolism of branched-chain amino acids (BCAA) leucine, isoleucine, and valine. Children with MSUD suffer from bouts of metabolic decompensation, which may lead to neurological damage. Liver transplantation from unrelated deceased donors has been considered curative. The natural history of the disease following transplantation using a haploidentical (obligate heterozygous) living donor is still unclear, although previously described as favorable. We describe acute metabolic crises in a 20-month-old child with MSUD type II. The first well-documented one occurred 5 months after a successful liver transplantation from his mother. The patient developed encephalopathy with progressive lethargy and seizures after an episode of gastroenteritis with dehydration. Plasma levels of leucine, isoleucine, and valine were markedly elevated and alloisoleucine was detected. He promptly responded to dialysis and BCAA-free dietetic management and subsequently could resume a normal diet. Since then he has had another symptomatic metabolic crisis with seizures. This case strongly suggests that some recipients of liver transplantation from a haploidentical parent possess limited capacity to oxidize BCAA at the time of catabolic stress and dehydration and remain at risk of severe metabolic crises. Thus, careful metabolic monitoring and prompt treatment post liver transplantation are still required to avoid neurological sequelae of MSUD, particularly if the donor is heterozygous for MSUD.
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PMID:Acute Metabolic Crises in Maple Syrup Urine Disease After Liver Transplantation from a Related Heterozygous Living Donor. 2711 95