Nutritional and metabolic parameters of children and adolescents with phenylketonuria

Considering that phenylalanine-poor diets may be monotonous and compromise the development and nutritional status of children and adolescents with phenylketonuria, the aim of this study was to evaluate the anthropometric and biochemical characteristics of children and adolescents with this condition.

Retrospective study with anthropometric and biochemical data collection from patients with phenylketonuria in the age group 2-19.9 years. Nutritional status was classified according to the World Health Organization. Biochemical tests were compared to current recommendations.

A total of 84 patients (71.8%) were eligible, with a median age of 10.7 years (2.4-19.9 years). There was predominance of adequate (n = 58, 69%) with presence of overweight and obesity in 24 (28.5%) patients. The biochemical tests revealed hyperphosphatemia in 46 (55%), hypertriglyceridemia in 27 (50%), vitamin B12 elevated in 34 (41.2%), selenium deficiency in 10 (13.7%), insufficient zinc in 7 (8.9%), low globulin in 21 (26.9%), low HDL in 35 (59.3%) and elevated phenylalanine level in 28 (34.5%) patients in the sample. Overweight and obesity were correlated with low HDL (p = 0.04) and lowest adequate frequency of LDL (p = 0.09). Higher phosphorus values were associated with lower body weight (r = -0.72) and age (r = -0.75), as well as vitamin B12 in the same parameters (r = -0.67 and r = -0, 68). A positive correlation of phenylalanine with body weight and age (r = 0.62 and r = 0.66) was observed.

Most patients presented adequate according to anthropometric parameters and appropriate biochemical tests, except HDL, and moderate metabolic control of the disease. However, attention should be paid to the presence of overweight and need for biochemical monitoring of triglycerides, selenium, zinc, HDL, and phenylalanine.