Infants maple syrup urine disease

Imbalances of brain amino acids may hinder the synthesis of brain lipids, leading to a diminution in the rate of myelin formation. Decreases of lipids, proteolipids and cerebrosides (Ch. 3) have been noted in several of these syndromes, e.g. maple syrup urine disease, when intra-myelinic edema is a prominent finding, particularly during the acute phase of metabolic decompensation [9]. Pathological changes in brain myelin are common, especially in infants who die early in life. The fundamental... 

Infants suffering from maple syrup urine disease exhibit failure to thrive, feeding problems, vomiting, dehydration, and severe metabolic acidosis, with mental retardation as a major sequela. 

C-11) (1-9) Maple Syrup Urine Disease. There is a block in the degradation of the branched chain amino acids. Leucine, isoleucine, valine, and their ketoic acids are elevated in the blood and urine. Assays for these chemicals can be done in the laboratory. The urine acquires a maple syrup aroma. Infants with the condition have a variety of neurologic problems, including mental retardation. The condition is treated by dietary restriction of the affected amino acids. 

Maple syrup urine disease is a genetic disease involving a defect in BCKA dehydrogenase. The disease affects one in 100,000 births, manifests in infants as leth-... 

The leucine-, isoleucine- and vafrne-free drink mix MSUD Aid III is suitable for infants, children, adolescents and adults but, unlike other proprietary preparations suitable for the management of Maple syrup urine disease, it is carbohydrate, fat, vitamin and mineral free, which need to be added to the diet. This may allow more appropriate age-specific supplementation including iodine. 

Infants administered large quantities of fenugreek, either directly or through maternal ingestion, have been observed to smell of maple syrup, which has led in some cases to false suspicion of maple syrup urine disease, a metabolic disease characterized by maple-scented urine (Bartley et al. 1981 Korman et al. 2001 Sewell et al. 1999). The compound sotolon is responsible for the maple scent (Korman et al. 2001). 

Because treatment is most effective if started in earliest infancy, it is necessary to make the diagnosis of phenylketonuria before any clinical signs appear, i.e. from the biochemical changes. Every newborn infant must be tested and, therefore, the test used must be inexpensive, simple and reliable [70, 71]. The available methods are determination of phenylalanine concentration in the blood, o-hydroxyphenyl-acetic acid in urine or phenylpyruvic acid in urine. The third method, once widely used, has now been largely abandoned the first and, to a lesser extent, the second are used on a very large scale in many countries. Sometimes tests for other conditions, such as homocystinuria, galactosaemia and maple syrup urine disease, are combined with the test for phenylketonuria. 

The most Important use of body odors in disease diagnosis relates to the infant diseases involving errors in amino acid metabolism. Strong and unusual odors are manifest in the breath, sweat, and urine of these individuals. Table II summarizes several known acidurias, the amino acids that are not properly metabolized, and the odors associated with the compounds which accumulate and can be detected in the urine ( ). In the case of the Maple Syrup Urine and Oasthouse syndrome, the keto- and hydroxy- acids which have been identified may not be responsible for the observed maple and celery/yeast odors (.9). Alternatively, these odors could be the result of conversion of 2-keto-butyrlc acid to methyl-ethyl-tetronlc acid (Slusser s lactone) which is used as an extender in maple and celery flavors and has a maple syrup-like odor (R. Soukup, personal communication). With these acidurias it is imperative that an immediate diagnosis is made, since corrective diet can prevent the brain damage that results from these diseases. This is readily done on an olfactory basis which can subsequently be supported by gas chromatographic... 

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