Monitoring of nutritional status, metabolic control and growth in patients with organic acidemia and urea cycle disorders

In patients with organic acidemia and urea cycle disorders, a diet restricted to natural protein and the use of amino acid mixtures when necessary are the basis of treatment. Patients having natural protein-restricted diet therapy could suffer from growth retardation and nutrient deficiencies. This study was carried out to monitor nutritional defeciencies, body composition, metabolic control, and growth in patients with organic acidemia and urea cycle disorders and to determine the relationship between them. The study included a study group of 81 patients aged between 1 and 18, comprising 36 individuals with maple syrup urine disease (MSUD), 30 with methylmalonic acidemia (MMA) or propionic acidemia (PPA), 6 with isovaleric acidemia (IVA), and 9 with urea cycle disorder (UCD). Long-term follow-up of the patients was carried out, and anthropometric measurements, 3-day food consumption records every month, food consumption frequencies, biochemical parameters indicating growth status, and blood amino acids were taken every 6 months. The daily consumption of protein and amino acids was evaluated according to the treatment guidelines specific to the disease. The blood amino acids of the patients were compared according to the disease-specific values. In addition, blood parameters indicating their metabolic control were retrospectively scanned from their files. At the beginning of the study, 36% of MSUD patients and 34.8% of MMA/PPA patients were malnourished according to the weight Z score for age, and at 6 months, these percentages increased of to 52.2% and 43.5%, respectively. At the beginning of the study, 47.2% of MSUD patients and 43.3% of MMA/PPA patients were identified as stunted according to the height Z score for age, and at 6 months, these percentages decreased to 44.4% and 50%, respectively. No growth retardation was found in IVA patients. In UCD patients, 44.4% were identified as stunted both at the beginning and at 6 months. From the food consumption records of the patients, it was found that their intake of polyunsaturated fatty acids and fiber was insufficient. The total protein: energy value taken by the patients was found to be normal in the normal interval, and there was no significant relationship between it and the Z score according to the dye (p>0,05). Most of the MSUD and MMA/PPA patients had low blood isoleucine and valine levels during their follow-up. As a result, growth retardation is observed in patients with organic acidemia and urea cycle disorders. There are very few studies in which growth and nutrition have been evaluated in those with inborn amino acid metabolism disorders. There is no consensus on the recommendations in the disease-specific treatment guidelines. A dietitian with expertise in metabolic diseases should closely monitor these patients' growth and nutrient deficiencies.