Evaluation of patients with phenylalanine metabolism disorder: a single center experience
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Sahin Erdol
and
Huseyin Bilgin
Abstract
Aim
The aim is to evaluate the clinical, demographic and laboratory data of the patients we followed up with phenylalanine metabolism disorder.
Materials and methods
In this study, patients with phenylalanine metabolism disorder who applied to Bursa Uludag University Faculty of Medicine, Department of Pediatrics, Pediatric Metabolism Department between 2011 and 2021 were retrospectively examined. The files of 397 patients who were followed up in our pediatric metabolism outpatient clinic and were found to have phenylalanine metabolism disorder by plasma phenylalanine level and molecular genetic analysis were evaluated.
Results
According to the highest plasma phenylalanine levels at admission, mild hyperphenylalaninemia phenotype constituted the largest group of 397 patients with 282 cases (71.1%), while the least common phenotype was malignant phenylketonuria (BH4 metabolism disorder) with four patients (1.0%). The number of patients with classical phenylketonuria was 90 (22.6%). 61 (62.8%) of 97 phenylalanine metabolism disorder cases who underwent BH4 loading test had a response. The mean phenylalanine level of the patients was 3.62 ± 1.31 mg/dL in mild hyperphenylalaninemia, 7.98 ± 3.99 mg/dL in mild phenylketonuria and 11.71 ± 4.39 mg/dL in classical phenylketonuria. While 241 (76%) of 317 patients younger than 8 years old were in the well-controlled group, 76 (24%) were in the poorly-controlled group. While 41 (53.9%) of 76 patients older than 8 years of age were in the well-controlled group, 35 (46.1%) were in the poorly-controlled group.
Conclusions
In our study, the largest patient group consisted of patients with mild hyperphenylalaninemia, and the least common phenotype was mild phenylketonuria.
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Research funding: None declared.
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Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Competing interests: Authors state no conflict of interest.
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Informed consent: Not applicable.
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Ethical approval: Ethics committee approval was obtained.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Review Article
- Nephrogenic diabetes insipidus: a comprehensive overview
- Original Articles
- Prevalence of type 2 diabetes mellitus, metabolic syndrome, and related morbidities in overweight and obese children
- Impact of sports participation on components of metabolic syndrome in adolescents: ABCD growth study
- Expected or unexpected clinical findings in liver glycogen storage disease type IX: distinct clinical and molecular variability
- Evaluation of patients with phenylalanine metabolism disorder: a single center experience
- The association of grandparental co-residence and dietary knowledge with excess body weight among children aged 7–15 years in China
- Clinical characteristics of polyglandular autoimmune syndromes in pediatric age: an observational study
- Serum kisspeptin, leptin, neuropeptide Y, and neurokinin B levels in adolescents with polycystic ovary syndrome
- Ultrasonographic measurements of the testicular volume in Turkish boys aged 0–8 years and comparison with international references
- Fructose 1,6 bisphosphatase deficiency: outcomes of patients in a single center in Turkey and identification of novel splice site and indel mutations in FBP1
- Benefits of metformin add-on insulin therapy (MAIT) for HbA1c and lipid profile in adolescents with type 1 diabetes mellitus: preliminary report from a double-blinded, placebo-controlled, randomized clinical trial
- Evaluation of efficacy and safety of long-acting PEGylated recombinant human growth hormone (Jintrolong) for patients with growth hormone deficiency
- Evaluation of endocrinological involvement and metabolic status in patients with Gaucher disease Type 1 and Fabry disease under enzyme replacement therapy
- Letter to the Editor
- Correspondence on “Obesity after the Covid-19 pandemic”
- Case Reports
- An unusual presentation of primary adrenal insufficiency with new onset type 1 diabetes: case report and review of the literature
- Niemann–Pick type C disease with a novel intronic mutation: three Turkish cases from the same family
- Weight management in youth with rapid-onset obesity with hypothalamic dysregulation, hypoventilation, autonomic dysregulation, and neural crest tumor (ROHHAD-NET): literature search and case report
- Successful use of cinacalcet monotherapy in the management of siblings with homozygous calcium-sensing receptor mutation
Articles in the same Issue
- Frontmatter
- Review Article
- Nephrogenic diabetes insipidus: a comprehensive overview
- Original Articles
- Prevalence of type 2 diabetes mellitus, metabolic syndrome, and related morbidities in overweight and obese children
- Impact of sports participation on components of metabolic syndrome in adolescents: ABCD growth study
- Expected or unexpected clinical findings in liver glycogen storage disease type IX: distinct clinical and molecular variability
- Evaluation of patients with phenylalanine metabolism disorder: a single center experience
- The association of grandparental co-residence and dietary knowledge with excess body weight among children aged 7–15 years in China
- Clinical characteristics of polyglandular autoimmune syndromes in pediatric age: an observational study
- Serum kisspeptin, leptin, neuropeptide Y, and neurokinin B levels in adolescents with polycystic ovary syndrome
- Ultrasonographic measurements of the testicular volume in Turkish boys aged 0–8 years and comparison with international references
- Fructose 1,6 bisphosphatase deficiency: outcomes of patients in a single center in Turkey and identification of novel splice site and indel mutations in FBP1
- Benefits of metformin add-on insulin therapy (MAIT) for HbA1c and lipid profile in adolescents with type 1 diabetes mellitus: preliminary report from a double-blinded, placebo-controlled, randomized clinical trial
- Evaluation of efficacy and safety of long-acting PEGylated recombinant human growth hormone (Jintrolong) for patients with growth hormone deficiency
- Evaluation of endocrinological involvement and metabolic status in patients with Gaucher disease Type 1 and Fabry disease under enzyme replacement therapy
- Letter to the Editor
- Correspondence on “Obesity after the Covid-19 pandemic”
- Case Reports
- An unusual presentation of primary adrenal insufficiency with new onset type 1 diabetes: case report and review of the literature
- Niemann–Pick type C disease with a novel intronic mutation: three Turkish cases from the same family
- Weight management in youth with rapid-onset obesity with hypothalamic dysregulation, hypoventilation, autonomic dysregulation, and neural crest tumor (ROHHAD-NET): literature search and case report
- Successful use of cinacalcet monotherapy in the management of siblings with homozygous calcium-sensing receptor mutation
