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BACKGROUND: In 2011, a European phenylketonuria (PKU) survey reported that the blood phenylalanine (Phe) levels were well controlled in early life but deteriorated with age. Other studies have shown similar results across the globe. Different target blood Phe levels have been used throughout the years, and, in 2017, the European PKU guidelines defined new targets for blood Phe levels. This study aimed to evaluate blood Phe control in patients with PKU across Europe. METHODS: nine centres managing PKU in Europe and Turkey participated. Data were collected retrospectively from medical and dietetic records between 2012 and 2018 on blood Phe levels, PKU severity, and medications. RESULTS: A total of 1323 patients (age range:1-57, 51% male) participated. Patient numbers ranged from 59 to 320 in each centre. The most common phenotype was classical PKU (n = 625, 48%), followed by mild PKU (n = 357, 27%) and hyperphenylalaninemia (HPA) (n = 325, 25%). The mean percentage of blood Phe levels within the target range ranged from 65 ± 54% to 88 ± 49% for all centres. The percentage of Phe levels within the target range declined with increasing age (<2 years: 89%; 2-5 years: 84%; 6-12 years: 73%; 13-18 years: 85%; 19-30 years: 64%; 31-40 years: 59%; and ≥41 years: 40%). The mean blood Phe levels were significantly lower and the percentage within the target range was significantly higher (p < 0.001) in patients with HPA (290 ± 325 µmol/L; 96 ± 24%) and mild PKU (365 ± 224 µmol/L; 77 ± 36%) compared to classical PKU (458 ± 350 µmol/L, 54 ± 46%). There was no difference between males and females in the mean blood Phe levels (p = 0.939), but the percentage of Phe levels within the target range was higher in females among school-age children (6-12 years; 83% in females vs. 78% in males; p = 0.005), adolescents (13-18 years; 62% in females vs. 59% in males; p = 0.034) and adults (31-40 years; 65% in females vs. 41% in males; p < 0.001 and >41 years; 43% in females vs. 28% in males; p < 0.001). Patients treated with sapropterin (n = 222) had statistically significantly lower Phe levels compared to diet-only-treated patients (mean 391 ± 334 µmol/L; percentage within target 84 ± 39% vs. 406 ± 334 µmol/L; 73 ± 41%; p < 0.001), although a blood Phe mean difference of 15 µmol/L may not be clinically relevant. An increased frequency of blood Phe monitoring was associated with better metabolic control (p < 0.05). The mean blood Phe (% Phe levels within target) from blood Phe samples collected weekly was 271 ± 204 µmol/L, (81 ± 33%); for once every 2 weeks, it was 376 ± 262 µmol/L, (78 ± 42%); for once every 4 weeks, it was 426 ± 282 µmol/L, (71 ± 50%); and less than monthly samples, it was 534 ± 468 µmol/L, (70 ± 58%). CONCLUSIONS: Overall, blood Phe control deteriorated with age. A higher frequency of blood sampling was associated with better blood Phe control with less variability. The severity of PKU and the available treatments and resources may impact the blood Phe control achieved by each treatment centre.
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Fenilalanina , Fenilcetonúrias , Humanos , Fenilcetonúrias/sangue , Fenilalanina/sangue , Masculino , Adolescente , Criança , Feminino , Pré-Escolar , Europa (Continente) , Adulto , Adulto Jovem , Estudos Retrospectivos , Lactente , Pessoa de Meia-Idade , Turquia/epidemiologiaRESUMO
Protein substitutes (PS) without tyrosine (Tyr) and phenylalanine (Phe), are an essential source of synthetic protein in the treatment of tyrosinemia (HT). In the UK, the only available protein substitutes for HT are Tyr/ Phe free amino acid liquid or powders or formulations based on glycomacropeptide (CGMP). A tablet Tyr/ Phe free amino acid supplement (AAT) has now been introduced. The aim of this two-part prospective, longitudinal intervention study was to assess the efficacy, acceptability, and tolerance of AAT in children aged >8 years with HTI. Part 1: was a 28-day acceptability/ tolerance study, part 2, was a 12-month extension study examining efficacy of AAT. Anthropometry and blood Tyr/ Phe were assessed. All subjects were taking NTBC [2-(2-nitro-4-triflourothybenzoyl) cyclohexane-1, 3-dione] with a Tyr restricted diet. Eight subjects with HTI were recruited 4 boys, and 4 girls with a median age of 14.3y (range 10.4-17.3); 3 were Caucasian and 5 of Pakistani origin. The median (range) protein equivalent from PS was 60 g/d (50-60), natural protein 20 g/d (15-30), and NTBC 30 mg/d (25-80). No subjects were taking Phe supplements. Five (63%) subjects completed part 1, with 4 taking all their PS requirements as AAT. Subjects reported AAT were tasteless and had no odour. No adverse gastrointestinal symptoms were recorded, with two reporting improvements in abdominal discomfort. At 12 months, 4 subjects had a non-significant decrease in blood Tyr/ Phe compared to the 12 months pre-treatment. Median blood Tyr (µmol/ L) pre-intervention was 500 (320-590); and at 12 months, 450 (290-530). Median blood Phe (µmol/L) pre-intervention was 40 (30-40); and at 12 months 30 (30-50). Median height z scores remained unchanged, but there was a small decrease in weight z score (pre-study weight - 0.1 (-1.4 to1.1), 12 m - 0.3 (-1.4 to 1.3) and BMI (pre- study BMI 0.2 (-2 to 1.4), and 12 m, -0.1 (-2.5 to 1.5)). Conclusion: AAT were useful for some adolescents with HTI who struggled with the taste and volume of conventional powdered and liquid PS.
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The long-term efficacy and use of phenylalanine-free infant amino acid formula (PFIF) is understudied. This retrospective, longitudinal study evaluated PFIF (PKU Start: Vitaflo International) in children with phenylketonuria, collecting data on metabolic control, growth, dietary intake, and symptoms and the child's experience with PFIF. Twenty-five children (12 males, 48%) with a median age of 3.6 years (2.0-6.2 years) were included. During 24 months follow-up, children maintained normal growth and satisfactory metabolic control. The protein intake from protein substitutes increased from 2.7 at 6 months to 2.8 g/kg/day at 24 months, while natural protein decreased from 0.6 to 0.4 g/kg/day. By 24 months, most children (n = 16, 64%) had stopped PFIF, while nine (36%) continued with a median intake of 450 mL/day (Q1:300 mL, Q3: 560 mL). Children who continued PFIF after 24 months of age had higher energy and fat intakes with higher weight/BMI z-scores compared with those who stopped earlier (p < 0.05). Constipation was reported in 44% of infants but improved with age. Initial difficulty with PFIF acceptance was reported in 20% of infants but also improved with time. Prolonged use of PFIF in pre-school children may contribute to poor feeding patterns and overweight; thus, replacing the majority of the protein equivalent provided by PFIF with a weaning protein substitute by 12 months and discontinuing PFIF before 2 years is recommended.
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Fórmulas Infantis , Fenilalanina , Fenilcetonúrias , Humanos , Fenilcetonúrias/dietoterapia , Estudos Retrospectivos , Masculino , Feminino , Fenilalanina/sangue , Fenilalanina/administração & dosagem , Pré-Escolar , Lactente , Criança , Estudos Longitudinais , Proteínas Alimentares/administração & dosagem , Constipação Intestinal/dietoterapia , Ingestão de EnergiaRESUMO
In phenylketonuria (PKU), an important component of the UK dietary management system is a 50 mg phenylalanine (Phe)/1 g protein exchange system used to allocate the Phe/natural protein intakes according to individual patient tolerance. Any foods containing protein ≤ 0.5 g/100 g or fruits/vegetables containing Phe ≤ 75 mg/100 g are allowed without measurement or limit. In children with PKU, we aimed to assess the difference between the prescribed natural protein intake and their actual consumed intake, and to calculate the natural protein/Phe intake from foods given without measurement or restriction. Over a 6-month duration, three one-day diet diaries were collected every month by caregivers of children with PKU at the beginning of a follow-up study. Dietary intakes of Phe, as well as natural and total protein intakes, were calculated using Nutritics® (v5.09). Weekly blood Phe spots were collected by caregivers. The target blood Phe level was ≤360 µmol/L for ages up to 12 years and ≤600 µmol/L for ages ≥12 years. Sixteen early treated children (69% females) with PKU were recruited. The median age was 11 years (range: 9-13), and most had classical PKU (n = 14/16). A median of 18 (range 12-18) one-day diaries and 22 blood spots were analysed for each subject over 6 months. The median prescribed natural protein was 6 g/day (range: 3-27), but when calculated, the actual median intake from all foods consumed was 10 g/day (range: 4-37). The median prescribed Phe was 300 mg/day (range: 150-1350), but the actual median intake was 500 mg/day (range: 200-1850). The median difference between the prescribed and actual natural protein daily intakes was +4 g/day (range: -2.5 to +11.5), with a median percentage increase of 40% for natural protein/Phe intake (p < 0.001). The median blood Phe level was 250 µmol/L (range 20-750), with 91% of blood Phe levels within the target range. Only one patient (11 years) had less than 75% of their blood Phe levels within the target range. The UK Phe exchange system provides flexibility in the dietary management of PKU. With this method, the actual natural protein intake was 167% higher than the prescribed amount. Although this led to a variable daily protein intake, the majority of children (n = 15/16) experienced no deterioration in their metabolic control.
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Fenilcetonúrias , Criança , Feminino , Humanos , Masculino , Seguimentos , Dieta , Fenilalanina , PrescriçõesRESUMO
(1) Background: Good adherence to a Phe-restricted diet supplemented with an adequate amount of a protein substitute (PS) is important for good clinical outcomes in PKU. Glycomacropeptide (cGMP)-PSs are innovative, palatable alternatives to amino acid-based PSs (AA-PS). This study aimed to evaluate a new cGMP-PS in liquid and powder formats in PKU. (2) Methods: Children and adults with PKU recruited from eight centres were prescribed at least one serving/day of cGMP-PS for 7-28 days. Adherence, acceptability, and gastrointestinal tolerance were recorded at baseline and the end of the intervention. The blood Phe levels reported as part of routine care during the intervention were recorded. (3) Results: In total, 23 patients (powder group, n = 13; liquid group, n = 10) completed the study. The majority assessed the products to be palatable (77% of powder group; 100% of liquid group) and well tolerated; the adherence to the product prescription was good. A total of 14 patients provided blood Phe results during the intervention, which were within the target therapeutic range for most patients (n = 11) at baseline and during the intervention. (4) Conclusions: These new cGMP-PSs were well accepted and tolerated, and their use did not adversely affect blood Phe control.
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Caseínas , Fragmentos de Peptídeos , Adulto , Criança , Humanos , Pós , Suplementos Nutricionais , GMP CíclicoRESUMO
(1) Background: Poor palatability, large volume, and lack of variety of some liquid and powdered protein substitutes (PSs) for patients with phenylketonuria (PKU) and tyrosinemia (TYR) can result in poor adherence. This study aimed to evaluate a new unflavoured, powdered GMP-based PS designed to be mixed into drinks, foods, or with other PSs, in patients with PKU and TYR. (2) Methods: Paediatric and adult community-based patients were recruited from eight metabolic centres and prescribed ≥1 sachet/day (10 g protein equivalent (PE)) of the Mix-In-style PS over 28 days. Adherence, palatability, GI tolerance, and metabolic control were recorded at baseline and follow-up. Patients who completed at least 7 days of intervention were included in the final analysis. (3) Results: Eighteen patients (3-45 years, nine males) with PKU (n = 12) and TYR (n = 6) used the Mix-In-style PS for ≥7 days (mean 26.4 days (SD 4.6), range 11-28 days) alongside their previous PS, with a mean intake of 16.7 g (SD 7.7) PE/day. Adherence was 86% (SD 25), and GI tolerance was stable, with n = 14 experiencing no/no new symptoms and n = 3 showing improved symptoms compared to baseline. Overall palatability was rated satisfactory by 78% of patients, who successfully used the Mix-In-style PS in various foods and drinks, including smoothies, squash, and milk alternatives, as a top-up to meet their protein needs. There was no concern regarding safety/metabolic control during the intervention. (4) Conclusions: The 'Mix-In'-style PS was well adhered to, accepted, and tolerated. Collectively, these data show that providing a flexible, convenient, and novel format of PS can help with adherence and meet patients' protein needs.
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Fenilcetonúrias , Tirosinemias , Glicoproteínas/efeitos adversos , Glicoproteínas/uso terapêutico , Glicopeptídeos/efeitos adversos , Glicopeptídeos/uso terapêutico , Fenilcetonúrias/dietoterapia , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Tirosinemias/dietoterapia , Resultado do Tratamento , Trato Gastrointestinal/metabolismo , Alimentos , BebidasRESUMO
INTRODUCTION: In phenylketonuria (PKU) changes in dietary patterns and behaviors in sapropterin-responsive populations have not been widely reported. We aimed to assess changes in food quality, mental health and burden of care in a paediatric PKU sapropterin-responsive cohort. METHODS: In an observational, longitudinal study, patient questionnaires on food frequency, neophobia, anxiety and depression, impact on family and burden of care were applied at baseline, 3 and 6-months post successful sapropterin-responsiveness testing (defined as a 30% reduction in blood phenylalanine levels). RESULTS: 17 children (10.8 ± 4.2 years) completed 6-months follow-up. Patients body mass index (BMI) z-scores remained unchanged after sapropterin initiation. Blood phenylalanine was stable. Natural protein increased (p < 0.001) and protein substitute intake decreased (p = 0.002). There were increases in regular cow's milk (p = 0.001), meat/fish, eggs (p = 0.005), bread (p = 0.01) and pasta (p = 0.011) intakes but special low-protein foods intake decreased. Anxiety (p = 0.016) and depression (p = 0.022) decreased in caregivers. The impact-on-family, familial-social impact (p = 0.002) and personal strain (p = 0.001) lessened. After sapropterin, caregivers spent less time on PKU tasks, the majority ate meals outside the home more regularly and fewer caregivers had to deny food choices to their children. CONCLUSION: There were significant positive changes in food patterns, behaviors and burden of care in children with PKU and their families after 6-months on sapropterin treatment.
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Dieta , Fenilcetonúrias , Animais , Bovinos , Feminino , Pão , Seguimentos , Estudos Longitudinais , Fenilcetonúrias/tratamento farmacológicoRESUMO
In phenylketonuria (PKU), a previous intervention study assessing the patients ability to tolerate fruits and vegetables containing phenylalanine 76-100 mg/100 g without limit or measurement, found that an extra 50 mg/day phenylalanine, but not 100 mg/day, was tolerated from these fruits and vegetables. In a further 6-month extension study, we examined the effect of the 'free' use of this group of fruits and vegetables on blood phenylalanine control. For 6 months, the patients ate fruits and vegetables containing phenylalanine 76-100 mg/100 g without limit or measurement. Three-day diet diaries and the patients' weights were collected monthly. Blood phenylalanine spots were collected weekly aiming for blood phenylalanine levels <360 µmol/L. Retrospective blood phenylalanine was collected 6 months pre-trial. All 16 patients (69% females) from the intervention study took part in the extension study. Most of the patients (n = 14/16) had classical PKU with a median age of 10.5 years (range: 6-13). There was no statistically significant difference in the median blood phenylalanine pre-study (270, range: 50-760 µmol/L) compared to the 6-month extension study (250, range: 20-750 µmol/L) (p= 0.4867). The patients had a median of 21 and 22 bloodspots, pre- and post-trial, respectively. In the extension study, the patients had an actual mean intake of 11 g/day (4-37) natural protein and 65 g/day (60-80) protein equivalent from a protein substitute. The mean phenylalanine intake was 563 mg/day (200-1850) with only 19 mg/day (0-146) phenylalanine from fruits and vegetables containing phenylalanine 76-100 mg/100 g. The weight z-scores remained unchanged (1.52 vs. 1.60, p = 0.4715). There was no adverse impact on blood phenylalanine control when fruits and vegetables containing phenylalanine 76-100 mg/100 g were eaten without limit or measurement. However, the fruits and vegetable portion sizes eaten were small (60 g/week). Further longitudinal work is necessary to examine the 'free' use of fruits and vegetables containing phenylalanine 76-100 mg/100 g on metabolic control in patients with PKU.
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Fenilcetonúrias , Verduras , Feminino , Humanos , Criança , Adolescente , Masculino , Frutas , Fenilalanina , Estudos Retrospectivos , Seguimentos , Dados PreliminaresRESUMO
BACKGROUND: A diagnosis of phenylketonuria (PKU) in an infant is a devastating and overwhelming event for their parents. Providing appropriate information and support is paramount, especially at the beginning of a child's life. Investigating if parents are receiving the right support is important for continued care. METHODOLOGY: An online survey was distributed to explore parents' perceptions of current support and information provided by their healthcare provider and to rate sources of other support (n = 169 participants). RESULTS: Dietitians received the highest (85%) rate of "very helpful" support. Overall, parents found Facebook to be helpful for support but had mixed reactions when asked if healthcare professionals (HCPs) should provide advice as part of the groups. When rating the most effective learning methods, the top three were 1:1 teaching sessions (n = 109, 70%), picture books (n = 73, 50%), and written handouts (n = 70, 46%). CONCLUSION: Most parents are happy with the support and information they receive from their dietitian but required more support from other HCPs. Facebook groups provide parents with the social support that HCPs and their family may be unable to offer, suggesting a place for social media in future PKU care.
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Nutricionistas , Fenilcetonúrias , Criança , Humanos , Lactente , Pais , Pessoal de Saúde , PercepçãoRESUMO
BACKGROUND: Phenylalanine-free infant formula is an essential source of safe protein in a phenylalanine restricted diet, but its efficacy is rarely studied. We report a multicentre, open, longitudinal, prospective intervention study on a phenylalanine-free infant formula (PKU Start: Vitaflo International Ltd.). RESULTS: This was a 2-part study: part I (28 days short term evaluation) and part II (12 months extension). Data was collected on infant blood phenylalanine concentrations, dietary intake, growth, and gastrointestinal tolerance. Ten infants (n = 8 males, 80%), with a median age of 14 weeks (range 4-36 weeks) were recruited from 3 treatment centres in the UK. Nine of ten infants completed the 28-day follow-up (one caregiver preferred the usual phenylalanine-free formula and discontinued the study formula after day 14) and 7/9 participated in study part II. The phenylalanine-free infant formula contributed a median of 57% (IQR 50-62%) energy and 53% (IQR 33-66%) of total protein intake from baseline to the end of the part II extension study. During the 12-month follow-up, infants maintained normal growth and satisfactory blood phenylalanine control. Any early gastrointestinal symptoms (constipation, colic, vomiting and poor feeding) improved with time. CONCLUSION: The study formula was well tolerated, helped maintain good metabolic control, and normal growth in infants with PKU. The long-term efficacy of phenylalanine-free infant formula should continue to be observed and monitored.
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Fórmulas Infantis , Fenilcetonúrias , Lactente , Masculino , Humanos , Estudos Prospectivos , Fenilalanina , ProteínasRESUMO
Introduction: There is little practical guidance about suitable food choices for higher natural protein tolerances in patients with phenylketonuria (PKU). This is particularly important to consider with the introduction of adjunct pharmaceutical treatments that may improve protein tolerance. Aim: To develop a set of guidelines for the introduction of higher protein foods into the diets of patients with PKU who tolerate >10 g/day of protein. Methods: In January 2022, a 26-item food group questionnaire, listing a range of foods containing protein from 5 to >20 g/100 g, was sent to all British Inherited Metabolic Disease Group (BIMDG) dietitians (n = 80; 26 Inherited Metabolic Disease [IMD] centres). They were asked to consider within their IMD dietetic team when they would recommend introducing each of the 26 protein-containing food groups into a patient's diet who tolerated >10 g to 60 g/day of protein. The patient protein tolerance for each food group that received the majority vote from IMD dietetic teams was chosen as its tolerance threshold for introduction. A virtual meeting was held using Delphi methodology in March 2022 to discuss and agree final consensus. Results: Responses were received from dietitians from 22/26 IMD centres (85%) (11 paediatric, 11 adult). For patients tolerating protein ≥15 g/day, the following foods were agreed for inclusion: gluten-free pastas, gluten-free flours, regular bread, cheese spreads, soft cheese, and lentils in brine; for protein tolerance ≥20 g/day: nuts, hard cheeses, regular flours, meat/fish, and plant-based alternative products (containing 5−10 g/100 g protein), regular pasta, seeds, eggs, dried legumes, and yeast extract spreads were added; for protein tolerance ≥30 g/day: meat/fish and plant-based alternative products (containing >10−20 g/100 g protein) were added; and for protein tolerance ≥40 g/day: meat/fish and plant-based alternatives (containing >20 g/100 g protein) were added. Conclusion: This UK consensus by IMD dietitians from 22 UK centres describes for the first time the suitability and allocation of higher protein foods according to individual patient protein tolerance. It provides valuable guidance for health professionals to enable them to standardize practice and give rational advice to patients.
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Fenilcetonúrias , Animais , Consenso , Dieta , Carne , Reino UnidoRESUMO
BACKGROUND: In children with phenylketonuria (PKU), transitioning protein substitutes at the appropriate developmental age is essential to help with their long-term acceptance and ease of administration. We assessed the parental experiences in transitioning from a second stage to third stage liquid or powdered protein substitute in patients with PKU. RESULTS: Sixteen interviews (23 open-ended questions) were carried out with parents/caregivers of children with PKU (8 females, 50%) with a median age of 8 years (range 5-11 years), continuously treated with diet, and on a third stage protein substitute. Parents/caregivers identified common facilitators and barriers during the third stage protein substitute transition process. The main facilitators were: child and parent motivation, parent knowledge of the transition process, a role model with PKU, low volume and easy preparation of the third stage protein substitute (liquid/powder), anticipation of increasing child independence, lower parent workload, attractive packaging, better taste and smell, school and teacher support, dietetic plans and guidance, PKU social events, child educational materials and written resources. The main barriers were child aversion to new protein substitutes, poor child behaviour, child aged > 5 years, parental fear of change, the necessity for parental time and persistence, loss of parental control, high product volume, different taste, smell, and texture of new protein substitutes, and peer bullying. CONCLUSION: A stepwise, supportive approach is necessary when transitioning from second to third stage protein substitutes in PKU. Future studies are needed to develop guidance to assist parents/caregivers, health professionals, and teachers during the transition process.
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Fenilcetonúrias , Criança , Feminino , Humanos , Pré-Escolar , Proteínas , Pais , CuidadoresRESUMO
Fruits and vegetables containing phenylalanine ≤ 75 mg/100 g (except potatoes) have little impact on blood phenylalanine in phenylketonuria (PKU). In a randomized, controlled, crossover intervention trial, we examined the effect of increasing phenylalanine intake from fruits and vegetables, containing phenylalanine 76−100 mg /100 g, compared with milk protein sources on blood phenylalanine control. This was a five-phase study (4 weeks each phase). In Phase A, patients remained on their usual diet and then were randomly allocated to start Phase B and C (an additional phenylalanine intake of 50 mg/day, then 100 mg from fruits and vegetables containing phenylalanine 76−100 mg/100 g) or Phase D and E (an additional phenylalanine intake of 50 mg/day then 100 mg/day from milk sources). There was a 7-day washout with the usual phenylalanine-restricted diet between Phase B/C and D/E. Blood phenylalanine was measured on the last 3 days of each week. If four out of six consecutive blood phenylalanine levels were >360 µmol/L in one arm, this intervention was stopped. Sixteen patients (median age 10.5 y; range 6−12 y) were recruited. At baseline, a median of 6 g/day (range: 3−25) natural protein and 60 g/day (range: 60−80) protein equivalent from protein substitute were prescribed. Median phenylalanine levels were: Phase A240 µmol/L; Phase B260 µmol/L; Phase C280 µmol/L; Phase D270 µmol/L and Phase E280 µmol/L. All patients tolerated an extra 50 mg/day of phenylalanine from fruit and vegetables, containing phenylalanine 76−100 mg/100 g, but only 11/16 (69%) tolerated an additional 100 mg /day. With milk protein, only 8/16 (50%) tolerated an extra 50 mg/day and only 5/16 (31%) tolerated an additional 100 mg/day of phenylalanine. Tolerance was defined as maintaining consistent blood phenylalanine levels < 360 µmol/L throughout each study arm. There was a trend that vegetable protein had less impact on blood phenylalanine control than milk protein, but overall, the differences were not statistically significant (p = 0.152). This evidence supports the PKU European Guidelines cutoff that fruit and vegetables containing 76−100 mg phenylalanine/100 g should be calculated as part of the phenylalanine exchange system. Tolerance of the 'free use' of these fruits and vegetables depends on inter-patient variability but cannot be recommended for all patients with PKU.
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Frutas , Fenilcetonúrias , Criança , Humanos , Proteínas de Vegetais Comestíveis , Proteínas do Leite , Verduras , FenilalaninaRESUMO
Patients with phenylketonuria (PKU) require a phenylalanine/protein-restricted diet, with limited food choice. Interpreting food labels, calculating protein intake, and determining food suitability are complex and confusing tasks. A mobile multi-media low-protein diet app was developed to guide food choice, label interpretation, and protein calculation. 'PKU Bite'® includes >1100 specialist and regular low-protein foods, is colour-coded for suitability, and features a protein calculator. A 12-week randomised controlled trial assessed app efficacy, compared with written/pictorial material, in 60 parents/caregivers of children with PKU, aged 1−16 years, and 21 adolescents with PKU. Questionnaires examined self-efficacy and label-reading knowledge; food records evaluated natural-protein intake, compared with prescriptions. There was no difference between groups in label-reading knowledge or self-efficacy, but there was a trend for improved accuracy of dietary protein calculation, when using the app (baseline/12-weeks: app 35%/48%; control 39%/35%). Parents of children <10 years of age (median 5.5 years), were most likely to use the app to check the phenylalanine/protein content of a food or to verify suitability of foods. Whilst the app was popular (43%), so too was contacting the dietitian (43%), using written/pictorial information (24%), or using social media (18%). This is the first dietary app for PKU to be studied in a systematic way as well as validated by healthcare professionals. It is a useful adjunct to existing resources and will be a valuable tool for educating parents of younger children.
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Aplicativos Móveis , Fenilcetonúrias , Adolescente , Criança , Dieta com Restrição de Proteínas , Humanos , Multimídia , Fenilalanina , Inquéritos e QuestionáriosRESUMO
Phenylketonuria (PKU) can lead to severe intellectual impairment unless a phenylalanine-restricted diet starts early in life. It requires expert user knowledge about the protein content of foods. The ability of adults or caregivers of children with PKU to calculate protein exchanges from food labels on manufactured foods and any difficulties they encounter in interpreting food labels has not been studied systematically. Individuals with PKU or their caregivers residing in the UK were invited to complete a cross-sectional online survey that collected both qualitative and quantitative data about their experience when calculating protein exchanges from the food labelling on prepackaged foods. Data was available from 246 questionnaire respondents (152 caregivers of patients with PKU aged <18 years, 57 patients with PKU aged ≥18 years or their caregivers (n = 28), and 9 teenagers with PKU). Thirty-one per cent (n = 76/246) found it difficult to interpret food protein exchanges from food labels. The respondents listed that the main issues with protein labelling were the non-specification of whether the protein content was for the cooked or uncooked weight (64%, n = 158/246); labels stating foods contained 0 g protein but then included protein sources in the list of ingredients (56%, n = 137/246); the protein content being given after a product was prepared with regular milk rather than the dry weight of the product (55%, n = 135/246); and the non-clarity of whether the protein content was for the weight of prepared or unprepared food (in addition to non-specification of cooked or uncooked weights on food labelling) (54%, n = 133/246). Over 90% (n = 222/246) of respondents had experienced problems with food labelling in the previous six months. Misleading or confusing protein labelling of manufactured foods was common. The food industry and legislators have a duty to provide accurate and clear protein food labelling to protect populations requiring low protein diets.
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Fenilcetonúrias , Adolescente , Adulto , Criança , Estudos Transversais , Dieta com Restrição de Proteínas , Alimentos , Rotulagem de Alimentos , HumanosRESUMO
Analysis of dietary patterns and their role in long-term health is limited in phenylketonuria (PKU). Food frequency questionnaires (FFQ) are commonly used to assess habitual intake. A semi-quantitative 89-item FFQ with a portion size photographic booklet was developed for children with PKU as a tool for collecting data on habitual intake of foods, food groups, energy and macronutrient intake. Twenty children with PKU aged 11−16 years, 30 parents of children with PKU aged 4−10 years, and 50 age/gender-matched control children were recruited. To test reproducibility, FFQs were completed twice with a mean interval of 5 weeks (range: 4−10). In order to test validity, FFQs were compared with five 24-h dietary recalls with a mean interval of 10 days (range: 6−18). Energy and macronutrient intake and quantity/week of individual food items were calculated and compared. There was good reproducibility for the FFQ with macronutrient correlations r > 0.6 and good validity data with most correlations r > 0.5. Bland−Altman plots for reproducibility and validity showed mean levels close to 0 and usually within 2 standard deviations. FFQ comparisons of PKU and control groups identified expected differences in % energy from macronutrients (PKU vs. control: carbohydrate 59% vs. 51%, fat 26% vs. 33%, protein 15% vs. 16%). This FFQ for PKU produced comparable data to repeated dietary recalls and is a valid tool for collecting data on habitual food and nutrient intake. It will be useful in assessing changes in dietary phenylalanine tolerance of new pharmacological treatments for PKU.
Assuntos
Dieta , Ingestão de Energia , Criança , Registros de Dieta , Inquéritos sobre Dietas , Dieta com Restrição de Proteínas , Humanos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
For patients with phenylketonuria (PKU), stringent dietary management is demanding and eating out may pose many challenges. Often, there is little awareness about special dietary requirements within the hospitality sector. This study's aim was to investigate the experiences and behaviours of people with PKU and their caregivers when dining out. We also sought to identify common problems in order to improve their experiences when eating outside the home. Individuals with PKU or their caregivers residing in the UK were invited to complete a cross-sectional online survey that collected both qualitative and quantitative data about their experiences when eating out. Data were available from 254 questionnaire respondents (136 caregivers or patients with PKU < 18 years and 118 patients with PKU ≥ 18 years (n = 100) or their caregivers (n = 18)). Fifty-eight per cent dined out once per month or less (n = 147/254) and the biggest barrier to more frequent dining was 'limited choice of suitable low-protein foods' (90%, n = 184/204), followed by 'no information about the protein content of foods' (67%, n = 137/204). Sixty-nine per cent (n = 176/254) rated their dining experience as less than satisfactory. Respondents ranked restaurant employees' knowledge of the PKU diet as very poor with an overall median rating of 1.6 (on a scale of 1 for extremely poor to 10 for extremely good). Forty-four per cent (n = 110/252) of respondents said that restaurants had refused to prepare alternative suitable foods; 44% (n = 110/252) were not allowed to eat their own prepared food in a restaurant, and 46% (n = 115/252) reported that restaurants had refused to cook special low-protein foods. Forty per cent (n = 101/254) of respondents felt anxious before entering restaurants. People with PKU commonly experienced discrimination in restaurants, with hospitality staff failing to support their dietary needs, frequently using allergy laws and concerns about cross-contamination as a reason not to provide suitable food options. It is important that restaurant staff receive training regarding low-protein diets, offer more low-protein options, provide protein analysis information on all menu items, and be more flexible in their approach to cooking low-protein foods supplied by the person with PKU. This may help people with PKU enjoy safe meals when dining out and socialising with others.
Assuntos
Cuidadores , Fenilcetonúrias , Estudos Transversais , Dieta com Restrição de Proteínas , Humanos , RefeiçõesRESUMO
Children spend a substantial part of their childhood in school, so provision of dietary care and inclusion of children with phenylketonuria (PKU) in this setting is essential. There are no reports describing the dietary support children with PKU receive whilst at school. The aim of this cross-sectional study was to explore the experiences of the dietary management of children with PKU in schools across the UK. Data was collected using an online survey completed by parents/caregivers of children with PKU. Of 159 questionnaire responses, 92% (n = 146) of children attended state school, 6% (n = 10) private school and 2% (n = 3) other. Fourteen per cent (n = 21/154) were at nursery/preschool, 51% (n = 79/154) primary and 35% (n = 54/154) secondary school. Sixty-one per cent (n = 97/159) said their child did not have school meals, with some catering services refusing to provide suitable food and some parents distrusting the school meals service. Sixty-one per cent of children had an individual health care plan (IHCP) (n = 95/155). Children were commonly unsupervised at lunchtime (40%, n = 63/159), with snacks (46%, n = 71/155) and protein substitute (30%, n = 47/157), with significantly less supervision in secondary than primary school (p < 0.001). An IHCP was significantly associated with improved supervision of food and protein substitute administration (p < 0.01), and better communication between parents/caregivers and the school team (p < 0.05). Children commonly accessed non-permitted foods in school. Therefore, parents/caregivers described important issues concerning the school provision of low phenylalanine food and protein substitute. Every child should have an IHCP which details their dietary needs and how these will be met safely and discreetly. It is imperative that children with PKU are supported in school.
Assuntos
Dieta com Restrição de Proteínas/psicologia , Serviços de Alimentação/organização & administração , Pais/psicologia , Fenilcetonúrias/dietoterapia , Serviços de Saúde Escolar/organização & administração , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Dieta com Restrição de Proteínas/métodos , Feminino , Humanos , Masculino , Instituições Acadêmicas , Inquéritos e Questionários , Reino UnidoRESUMO
Tyrosinemia type I (HTI) is treated with nitisinone, a tyrosine (Tyr) and phenylalanine (Phe)-restricted diet, and supplemented with a Tyr/Phe-free protein substitute (PS). Casein glycomacropeptide (CGMP), a bioactive peptide, is an alternative protein source to traditional amino acids (L-AA). CGMP contains residual Tyr and Phe and requires supplementation with tryptophan, histidine, methionine, leucine, cysteine and arginine. AIMS: a 2-part study assessed: (1) the tolerance and acceptability of a low Tyr/Phe CGMP-based PS over 28 days, and (2) its long-term impact on metabolic control and growth over 12 months. METHODS: 11 children with HTI were recruited and given a low Tyr/Phe CGMP to supply all or part of their PS intake. At enrolment, weeks 1 and 4, caregivers completed a questionnaire on gastrointestinal symptoms, acceptability and ease of PS use. In study part 1, blood Tyr and Phe were assessed weekly; in part 2, weekly to fortnightly. In parts 1 and 2, weight and height were assessed at the study start and end. RESULTS: Nine of eleven children (82%), median age 15 years (range 8.6-17.7), took low Tyr/Phe CGMP PS over 28 days; it was continued for 12 months in n = 5 children. It was well accepted by 67% (n = 6/9), tolerated by 100% (n = 9/9) and improved gastrointestinal symptoms in 2 children. The median daily dose of protein equivalent from protein substitute was 60 g/day (range 45-60 g) with a median of 20 g/day (range 15 to 30 g) from natural protein. In part 2 (n = 5), a trend for improved blood Tyr was observed: 12 months pre-study, median Tyr was 490 µmol/L (range 200-600) and Phe 50 µmol/L (range 30-100); in the 12 months taking low Tyr/Phe CGMP PS, median Tyr was 430 µmol/L (range 270-940) and Phe 40 µmol/L (range 20-70). Normal height, weight and BMI z scores were maintained over 12 months. CONCLUSIONS: In HTI children, CGMP was well tolerated, with no deterioration in metabolic control or growth when studied over 12 months. The efficacy of CGMP in HTI needs further investigation to evaluate the longer-term impact on blood Phe concentrations and its potential influence on gut microflora.
Assuntos
Caseínas/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Tirosinemias/dietoterapia , Adolescente , Aminoácidos/administração & dosagem , Aminoácidos/sangue , Criança , Pré-Escolar , Cicloexanonas/administração & dosagem , Dieta/métodos , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Feminino , Humanos , Masculino , Nitrobenzoatos/administração & dosagem , Fenilalanina/administração & dosagem , Fenilalanina/sangue , Estudos Prospectivos , Tirosina/administração & dosagem , Tirosina/sangueRESUMO
In a retrospective review, we aimed to assess long-term growth in 17 patients (n = 11 males) with hereditary tyrosinaemia type I (HTI). Median age at assessment was 15.6 years (5.7-26.6 years) and median age at diagnosis was 1 month (range: 0-16 months), with 35% (n = 6/17) symptomatic on presentation. From the age of 8 years, there was a noticeable change in median height, weight, and body-mass-index [BMI]-z-scores. Median height-for-age z-scores were consistently ≤ -1 (IQR -1.6, -0.5) during the first 8 years of life but increased with age. Weight-for-age z-scores ranged between -1 to 0 (IQR -1.2, 0.1) in the first 8 years; then increased to > 0.5 (IQR -0.3, 1.3) by age 16 years, and BMI-for-age z-scores ranged from 0 to 1 (IQR -0.7, 1.3) up to 8 years, and >1 (IQR -0.2, 1.9) until 16 years. The percentage of overweight and obesity was lowest in children aged < 5 years, and consistently > 40% in patients aged between 7 to 16 years. The prescribed total protein intake was associated with improved height growth (p < 0.01). Impaired growth in early life improved with age achieving normal population standards. Further studies are needed to investigate factors that influence growth outcome in HTI patients.