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

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.

Cardiovascular findings in classic homocystinuria.

OBJECTIVE: describe cardiovascular findings from echocardiograms and electrocardiograms in patients with Classic Homocystinuria. METHODS: this retrospective exploratory study evaluated fourteen subjects with Classic Homocystinuria (median age = 27.3 years; male n = 8, B6-non-responsive n = 9 patients), recruited by convenience sampling from patients seen Hospital de Clínicas de Porto Alegre (Brazil), between January 1997 and July 2020. Data on clinical findings, echocardiogram and electrocardiogram were retrieved from medical records. RESULTS: Eight patients presented some abnormalities on echocardiogram (n = 6) or electrocardiogram (n = 5). The most frequent finding was mild tricuspid regurgitation (n = 3), followed by mitral valve prolapse, mild mitral regurgitation, enlarged left atrium and aortic valve sclerosis (n = 2 patients each). Aortic root ectasia was found in one patient. Venous thrombosis was reported in six patients: deep vein thrombosis of lower limbs (n = 3), ischaemic stroke (n = 1), cerebral venous sinus thrombosis (n = 1) and pulmonary vein thrombosis (n = 1). CONCLUSION: mild valvulopathies seen to be common in patients with Classic Homocystinuria, but more studies regarding echocardiogram and electrocardiogram in this population are needed to draw absolute conclusions.

The rs2229611 (G6PC:c.*23 T>C) is associated with glycogen storage disease type Ia in Brazilian patients.

The rs2229611 SNP (G6PC:c.*23T>C) in the 3'UTR region of the G6PC gene affects the stability of the glucose-6-phosphatase mRNA and occurs in a higher frequency in patients with glycogenosis Ia (GSD Ia) in some populations. Herein, a group of Brazilian patients (n = 116) was analyzed by NGS and the frequency of rs2229611:T>C was determined. The linkage disequilibrium (LD) between pathogenic variants and the rs2229611:T>C SNP was evaluated. The results showed that the rs2229611:T>C is associated to GSD Ia and is in LD with the most frequent pathogenic variants in Brazilian patients with GSD Ia.