Research Article

Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis

Volume: 19 Number: 2 March 24, 2025
TR EN

Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis

Abstract

Objective: Phenylketonuria is a metabolic disorder resulting from mutations in the PAH gene, causing elevated blood phenylalanine (Phe) levels which can lead to severe neurological damage if untreated. The primary treatment is a lifelong low-protein diet with amino acid substitutes and micronutrient supplements. During the COVID-19 pandemic, classical phenylketonuria (PKU) patients faced significant challenges, including restricted access to routine care like clinical visits and metabolic control monitoring. The aim of the this study was to examine the disruptions in outpatient visits, the variances in pre- and post-pandemic Phe levels, and clinical severity among patients who contracted COVID-19. Material and Methods: Starting from the pandemic date of March 11, 2020, demographic data, laboratory characteristics, and details about COVID-19 infection were retrospectively reviewed for classical PKU patients with accessible electronic records from March 2018 to March 2022. Results: When the median blood Phe levels before and after the pandemic were compared, a significant difference was found. We observed that adult patients diagnosed with classical PKU often defaulted on their follow-up appointments. Conclusion: The COVID-19 pandemic significantly disrupted the follow-up and management of classical PKU patients. However, no severe COVID-19 cases were reported among this population, suggesting they did not face an increased risk from the infection. This study emphasizes the critical need to develop robust strategies for patient engagement and follow-up, especially for adult classical PKU patients who are at risk of discontinuing routine care.

Keywords

Supporting Institution

The authors received no financial support for the research.

Project Number

GO22/176

Ethical Statement

This study received approval from the Hacettepe University Ethics Committee for Non-Interventional Clinical Studies (GO22/176, 2022/08–23).

References

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Details

Primary Language

English

Subjects

​Internal Diseases

Journal Section

Research Article

Early Pub Date

December 3, 2024

Publication Date

March 24, 2025

Submission Date

August 23, 2024

Acceptance Date

October 7, 2024

Published in Issue

Year 2025 Volume: 19 Number: 2

APA
Kahraman, A. B., Yıldız, Y., Geçici, N. N., Çıkı, K., Erdal, İ., Akar, H. T., Dursun, A., Tokatli, A., & Sivri, S. (2025). Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis. Türkiye Çocuk Hastalıkları Dergisi, 19(2), 59-63. https://doi.org/10.12956/tchd.1537456
AMA
1.Kahraman AB, Yıldız Y, Geçici NN, et al. Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis. Turkish J Pediatr Dis. 2025;19(2):59-63. doi:10.12956/tchd.1537456
Chicago
Kahraman, Ayca Burcu, Yılmaz Yıldız, Neslihan Nisa Geçici, et al. 2025. “Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis”. Türkiye Çocuk Hastalıkları Dergisi 19 (2): 59-63. https://doi.org/10.12956/tchd.1537456.
EndNote
Kahraman AB, Yıldız Y, Geçici NN, Çıkı K, Erdal İ, Akar HT, Dursun A, Tokatli A, Sivri S (March 1, 2025) Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis. Türkiye Çocuk Hastalıkları Dergisi 19 2 59–63.
IEEE
[1]A. B. Kahraman et al., “Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis”, Turkish J Pediatr Dis, vol. 19, no. 2, pp. 59–63, Mar. 2025, doi: 10.12956/tchd.1537456.
ISNAD
Kahraman, Ayca Burcu - Yıldız, Yılmaz - Geçici, Neslihan Nisa - Çıkı, Kısmet - Erdal, İzzet - Akar, Halil Tuna - Dursun, Ali - Tokatli, Ayşegül - Sivri, Serap. “Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis”. Türkiye Çocuk Hastalıkları Dergisi 19/2 (March 1, 2025): 59-63. https://doi.org/10.12956/tchd.1537456.
JAMA
1.Kahraman AB, Yıldız Y, Geçici NN, Çıkı K, Erdal İ, Akar HT, Dursun A, Tokatli A, Sivri S. Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis. Turkish J Pediatr Dis. 2025;19:59–63.
MLA
Kahraman, Ayca Burcu, et al. “Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis”. Türkiye Çocuk Hastalıkları Dergisi, vol. 19, no. 2, Mar. 2025, pp. 59-63, doi:10.12956/tchd.1537456.
Vancouver
1.Ayca Burcu Kahraman, Yılmaz Yıldız, Neslihan Nisa Geçici, Kısmet Çıkı, İzzet Erdal, Halil Tuna Akar, Ali Dursun, Ayşegül Tokatli, Serap Sivri. Impact of the COVID-19 Era on Phenylalanine Levels and Classical Phenylketonuria Patients Follow-Up: A Retrospective Analysis. Turkish J Pediatr Dis. 2025 Mar. 1;19(2):59-63. doi:10.12956/tchd.1537456


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