Current Practices and Challenges in the Diagnosis and Management of PKU in Latin America: A Multicenter Survey

Abstract

This study aimed to describe the current practices in the diagnosis and dietary management of phenylketonuria (PKU) in Latin America, as well as the main barriers to treatment. We developed a 44-item online survey aimed at health professionals. After a pilot test, the final version was sent to 25 practitioners working with inborn errors of metabolism (IEM) in 14 countries. Our results include 22 centers in 13 countries. Most countries (12/13) screened newborns for PKU. Phenylalanine (Phe) targets at different ages were very heterogeneous among centers, with greater consistency at the 0–1 year age group (14/22 sought 120–240 µmol/L) and the lowest at >12 years (10 targets reported). Most countries had only unflavored powdered amino acid substitutes (10/13) and did not have low-protein foods (8/13). Only 3/13 countries had regional databases of the Phe content of foods, and only 4/22 centers had nutrient analysis software. The perceived obstacles to treatment were: low purchasing power (62%), limited/insufficient availability of low-protein foods (60%), poor adherence, and lack of technical resources to manage the diet (50% each). We observed a heterogeneous scenario in the dietary management of PKU, and most countries experienced a lack of dietary resources for both patients and health professionals.

Burden of phenylketonuria in Latin American patients: a systematic review and meta-analysis of observational studies

“…Sixty-four of the 79 included studies reported at least one patient-important outcome at individual or population level, and they are displayed in Table 1 for study characteristics. Regarding study design, 18 were case series [ 22 , 23 , 33 , 34 , 40 – 42 , 45 , 54 , 55 , 58 , 60 , 70 , 84 – 87 ], 47 cross-sectional studies [ 6 , 7 , 13 – 15 , 17 – 21 , 24 , 26 , 29 , 30 , 35 – 39 , 43 , 46 , 47 , 53 , 56 , 59 , 61 , 62 , 67 , 68 , 71 , 73 , 75 – 77 , 79 – 81 , 88 – 91 ], 13 case reports [ 34 , 44 , 48 , 51 , 63 , 64 , 69 , 74 , 84 , 87 , 92 – 94 ], and two cohort studies [ 57 , 95 ].…”

“…The type of patient-important outcomes most frequently reported among the cross-sectional and case series studies were neurological, neurocognitive and neuropsychiatric impairments (n = 33 studies, 50.8%) [ 21 , 22 , 24 , 27 , 30 – 33 , 38 – 40 , 43 , 45 , 53 – 55 , 59 – 61 , 67 , 68 , 77 , 78 , 81 , 83 – 89 , 91 , 98 ], followed by overweight (n = 11, 16.9%) [ 23 , 26 , 40 , 56 , 68 , 71 – 73 , 76 , 80 , 89 , 97 ], patient adherence to clinical recommendations (n = 10, 15.4%) [ 7 , 22 , 33 , 62 , 66 , 67 , 70 , 79 , 82 , 83 , 87 ], executive function deficit (n = 6, 92.3%) [ 21 , 24 , 58 – 61 ], socioeconomic impact (n = 7, 10.8%) [ 7 , 29 , 30 , 54 , 59 , 68 , 83 , 86 ], skin problems (n = 4, 6.2%) [ 54 , 55 , 68 , 96 ], osteopenia (n = 5, 7.7%) [ 17 – 19 , 23 ...…”

“…In the cross-sectional studies (Fig. 2 , panel A), at least one of the following domains of sample size, statistical significance, statistics methods, or demographic data were rated as “high risk of bias” in five studies (12.8%) [ 7 , 38 , 39 , 43 , 96 ]. In the case series studies (Fig.…”

“…The skills were related to performance in motor, linguistic and cognitive activities. Furthermore, Poloni et al [ 7 ] reported that most LATAM countries did not have low-protein foods, including Phe-free amino acid fortified, and no alternative treatments available. Also, they found that low purchasing power, limited/insufficient availability of low-protein foods, poor adherence, and lack of technical resources to manage the diet were major barriers to treatment.…”

“…Spefically concerning PKU, this genetic disorder is included in the NBS program for 14 countries (Cuba, Costa Rica, Chile, Uruguay, Argentina, Mexico, Brazil, Guatemala, Paraguay, Panama, Ecuador, Peru, Bolivia and Honduras) [ 6 ] with on average 92.3% of newborns in those countries screened for PKU. Regarding the availability of PKU treatment, half of the Latin America countries have fully subsidized medical foods by the government though the special low-protein foods are not available in most of the countries [ 7 ].…”