BackgroundSpecial low protein foods (SLPF) are essential in the nutritional management of patients with phenylketonuria (PKU). The study objectives were to: 1) identify the number of SLPF available for use in eight European countries and Turkey and 2) analyse the nutritional composition of SLPF available in one of these countries.MethodsEuropean Nutritionist Expert Panel on PKU (ENEP) members (Portugal, Spain, Belgium, Italy, Germany, Netherlands, UK, Denmark and Turkey) provided data on SPLF available in each country. The nutritional composition of Portuguese SLPF was compared with regular food products.ResultsThe number of different SLPF available in each country varied widely with a median of 107 [ranging from 73 (Portugal) and 256 (Italy)]. Food analysis of SLPF available from a single country (Portugal) indicated that the mean phenylalanine content was higher in low protein baby cereals (mean 48 mg/100 g) and chocolate/energy bars/jelly (mean 41 mg/100 g). The energy content of different foods from a sub-group of SLPF (cookies) varied widely between 23 and 96 kcal/cookie. Low protein bread had a high fat content [mean 5.8 g/100 g (range 3.7 to 10)] compared with 1.6 g/100 g in regular bread. Seven of the 12 SLPF sub-groups (58 %) did not declare any vitamin content, and only 4 (33 %) identified a limited number of minerals.ConclusionsWhilst equal and free access to all SLPF is desirable, the widely variable nutritional composition requires careful nutritional knowledge of all products when prescribed for individual patients with PKU. There is a need for more specific nutritional standards for special low protein foods.

Percutaneous endoscopic gastrostomy (PEG) is a standard procedure for feeding dysphagic amyotrophic lateral sclerosis (ALS) patients. Nevertheless, the effect of prognostic factors influencing survival after PEG remains unclear. We aimed to evaluate the prognostic value of several clinical features on survival after PEG placement. This study investigated 151 patients with ALS, in whom a PEG was inserted over the last 16 years in our centre. Survival curves were determined by Kaplan-Meier and the analysis of potential prognostic factors was performed by a Cox regression model. The overall median survival was 32 months, longer in spinal-onset disease patients - 42 vs. 29 months in bulbar-onset patients (p < 0.001). Median survival after PEG placement was 7.5 months, similar in both bulbar- and spinal-onset patients, 7.9 vs. 7.1 months, respectively. Thirteen percent of patients died within one month after PEG placement; this short-term survival was influenced by low forced vital capacity (FVC < 50%). In a multivariate analysis, only older age at disease onset was independently associated with poor outcome after PEG placement. In conclusion, survival after PEG placement was similar in bulbar- and spinal-onset patients, suggesting that the latter were in a more advanced stage at the time of PEG placement. Low FVC was associated with higher risk of short-term mortality. Older age at disease onset was associated with poorer outcome in bulbar-onset patients. Younger bulbar-onset patients are those who benefited most from PEG.

BACKGROUND/OBJECTIVES: Protein substitutes (PS) are an essential component in the dietary management of phenylketonuria (PKU). PS are available as phenylalanine-free amino-acid mixtures (AAM), glycomacropeptide-based PS (GMP) and large neutral amino acids (LNAA). There is a lack of information regarding their availability in different countries and comparison of their nutritional composition is limited. The objectives of this study were to identify the number of PS available in different European countries and Turkey and to compare their nutritional composition. SUBJECTS/METHODS: Members of the European Nutritionist Expert Panel on PKU (ENEP)

No abstract

In phenylketonuria (PKU), synthetic protein derived from L-amino acids (AAs) is essential in a low-phenylalanine (Phe) diet. Glycomacropeptide (GMP), an intact protein, is very low in Phe in its native form. It has been modified and adapted for PKU to provide an alternative protein source through supplementation with rate-limiting amino acids (GMP-AAs), although it still contains residual Phe. This review aims to systematically evaluate published intervention studies on the use of GMP-AAs in PKU by considering its impact on blood Phe control (primary aim) and changes in tyrosine control, nutritional biomarkers, and patient acceptability or palatability (secondary aims). Four electronic databases were searched for articles published from 2007 to June 2018. Of the 274 studies identified, only eight were included. Bias risk was assessed and a quality appraisal of the body of evidence was completed. A meta-analysis was performed with two studies with adequate comparable methodology which showed no differences between GMP-AAs and AAs for any of the interventions analysed. This work underlines the scarcity and nature of studies with GMP-AAs interventions. All were short-term with small sample sizes. There is a need for better-designed studies to provide the best evidence-based recommendations.

Background: In phenylketonuria (PKU), modified casein glycomacropeptide supplements (CGMP-AA) are used as an alternative to the traditional phenylalanine (Phe)-free L-amino acid supplements (L-AA). However, studies focusing on the long-term nutritional status of CGMP-AA are lacking. This retrospective study evaluated the long-term impact of CGMP-AA over a mean of 29 months in 11 patients with a mean age at CGMP-AA onset of 28 years (range 15 to 43) [8 females; 2 hyperphenylalaninaemia (HPA), 3 mild PKU, 3 classical PKU and 3 late-diagnosed]. Outcome measures included metabolic control, anthropometry, body composition and biochemical parameters. Results: CGMP-AA, providing 66% of protein substitute intake, was associated with no significant change in blood Phe with CGMP-AA compared with baseline (562 ± 289 µmol/L vs 628 ± 317 µmol/L; p=0.065). In contrast, blood tyrosine significantly increased on CGMP-AA (52.0 ± 19.2 μmol/L vs 61.4 ± 23.8 μmol/L; p=0.027). Conclusions: Biochemical nutritional markers remained unchanged which is an encouraging finding in adults with PKU, many of whom are unable to maintain full adherence with nutritionally fortified protein substitutes. Longitudinal, prospective studies with larger sample sizes are necessary to fully understand the metabolic impact of using CGMP-AA in PKU.

A high sodium intake is associated with high blood pressure, an important risk factor for noncommunicable diseases (NCDs). In contrast, the ingestion of high levels of potassium counteracts this negative effect of high sodium intake on blood pressure, thus reducing the sodium-to-potassium ratio. The aim of this work was to determine the sodium and potassium content of meals served in university canteens in Portugal. The analysis included 35 samples of soup and 35 samples of main dish collected at 5 random days from a total of 7 university canteens. The samples were analyzed for sodium and potassium by atomic emission spectrometry technique. On average, a meal (soup and main dish) had a sodium content of 1,069.4 mg (mean sodium content was 671.4 ± 374.5 mg/portion in the main dish and 398.0 ± 153.0 mg/portion in the soup) and a potassium content of 1,004 mg (mean potassium content was 731.4 ± 385.9 mg/serving in the main dish and 272.6 ± 272.6 mg/serving in the soup). Our results revealed that with a single university meal, students can reach 53% of the maximum daily value recommended for sodium and 27% of the minimum daily value recommended for potassium. An investment to decrease sodium and increase potassium in meals served is imperative in order to prevent NCDs.

Amino acid mixtures (AAM) are protein substitutes used for phenylketonuria treatment, but their metabolic effects have not been well characterized. The objective of this study was to compare the acute glycemic response to free amino acids (free AA) from AAM with the response to intact protein (iProtein).Male Wistar rats (n = 14) were administered by gavage a bolus of free AA (n = 7) or iProtein as albumin (n = 7) containing equivalent amounts of nitrogen. Blood glucose and insulin levels were measured at baseline and 15, 30, 60 and 120 minutes later, when gut GLP-1 content and pancreatic insulin, GLP-1 receptor and Ki67 expression were quantified at 120 minutes time point.After AAM, glucose area under the curve (free AA vs iProtein; P < 0.01), serum insulin levels at 120 minutes (free AA vs iProtein; P < 0.05), colon GLP-1 content (free AA vs iProtein; P < 0.01), pancreatic GLP-1 receptor (free AA vs iProtein; P < 0.01) and insulin expression (free AA vs iProtein; p < 0.01) were significantly lower as compared with iProtein. AAM increased Ki67 expression in pancreatic islets (free AA vs iProtein; P < 0.05). In conclusion, this study demonstrated that acute response to AAM differs from iProtein and is characterized by a lower glucose excursion, along with a decrease in gut GLP-1 and pancreatic GLP-1 receptor and insulin. This data suggests the modulation of glycemia by free AA is mediated by the incretin axis.