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Licensed Unlicensed Requires Authentication Published by De Gruyter November 11, 2020

Impact of sodium phenylbutyrate treatment in acute management of maple syrup urine disease attacks: a single-center experience

Tanyel Zubarioglu, Elif Dede, Humeyra Cigdem, Ertugrul Kiykim, Mehmet S. Cansever and Cigdem Aktuglu-Zeybek



Accurate management of metabolic decompensation in maple syrup urine disease (MSUD) has a crucial role, as acute attacks can cause neurological sequels and can be life threatening. Here, we aimed to evaluate effect of sodium phenylbutyrate (NaPBA) in acute management of MSUD attacks.


Episodes with an initial plasma leucine (Leu) level above 750 µmoL/L and that require hospitalization due to clinical findings of Leu neurotoxicity and/or feeding difficulties were included to the study. Patients who had no molecular diagnosis and a regular follow-up were excluded. Clinical findings, laboratory results and therapy responses were reviewed, retrospectively.


Ten patients who experienced 19 distinct episodes of MSUD attacks were enrolled. Initial median Leu level was 901.67 (range 756–1989.11) and 33.9 µmoL/L (range 7.91–347.3 µmoL/L) at the end of therapy. None of our patients underwent extracorporeal toxin removal during the course of attack. In patients with serial plasma quantitative amino acid sampling, mean Leu reduction rate was calculated to be 529.68 ± 250.08 µmoL/L/day at the 24th h of treatment and 318.72 ± 191.52 µmoL/L/day at the 48th h of treatment.


This study is the first original study that investigates the effect of NaPBA in management of acute attacks of MSUD patients from Turkey. We suggest that NaPBA treatment in MSUD attacks can ameliorate clinical and biochemical findings. This therapeutic option should be considered especially in smaller centers without the toxin removal chance and for patients who were not appropriate for extracorporeal toxin removal like hemodynamic instability.

Corresponding author: Tanyel Zubarioglu, Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, Department of Pediatrics Division of Nutrition and Metabolism, Kocamustafapasa Fatih, 34098, Istanbul, Turkey, Phone: +905363281439, E-mail:

  1. Research funding: There is no funding source.

  2. Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.

    TZ serves as the guarantor for the article. She accepts full responsibility for the work, had access to the data and controlled the decision to publish. She has been involved in conception, design, analysis and interpretation of the data and also drafting the article.

    ED has been involved in conception, design, analysis and interpretation of the data.

    HC has been involved in conception, design, analysis and interpretation of the data.

    EK has been involved in analysis and interpretation of the data.

    MSC has been involved in analysis and interpretation of the data.

    CAZ has been involved in conception, design, interpretation of the data and revising the article critically for important intellectual content.

  3. Competing interests: The funding organization(s) played no role in the study design; in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the report for publication.

  4. Informed consent: Informed consent was obtained from all individuals included in this study.

  5. Ethical approval: The local Institutional Review Board deemed the study exempt from review.


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Received: 2020-06-13
Accepted: 2020-09-21
Published Online: 2020-11-11
Published in Print: 2021-01-27

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