Leucinosis, or maple syrup urine disease (lecture and a clinical case)

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Maple syrup urine disease (leucinosis, short-chain ketoaciduria, branched-chain disease, branched-chain ketonuria) is an autosomal recessive disorder which is a consequence of the deficient branched-chain alpha ketoacid dehydrogenase complex. There are five subtypes of the disease: classical, intermediate, intermittent, thiamine-dependent and E3-deficient. Leucinosis is characterized by high plasma levels of branched-chain amino acids (leucine, isoleucine and valine) and high urine levels of branched-chain ketoacids, as well as of lactate and pyruvate. Tandem mass spectrometry can be used as a screening method in newborns. Mild disease cannot be identified at screening. The diagnosis should be based on tandem mass spectrometry of a blood sample and aminoacid analysis by gas chromatography of a urine sample. Prenatal diagnosis requires molecular genetic tests. Treatment of maple syrup urine disease is aimed at normalization of plasma branched-chain amino acids levels and includes two main components, namely, life-long diet therapy and active treatment of acute metabolic deterioration episodes. A favorable course of the disease is possible only with early (pre-symptomatic) initiation of treatment. The development of cognitive functions depends on plasma leucine levels. We present a clinical case of delayed diagnosis of leucinosis, despite its early clinical manifestation, leading to irreversible consequences for the patient.

About the authors

Ju. A. Tsareva

Saratov State Medical University named after V.I. Razumovsky

Author for correspondence.
Email: jutsareva@gmail.com
ORCID iD: 0000-0002-3483-7170

Julia A. Tsareva – MD, PhD, Associate Professor, Сhair of Pediatrics, Center of Continuing Professional Education

112 Bol'shaya Kazach'ya ul., Saratov, Saratovskaya oblast', 410012

Tel.: +7 (909) 340 85 89

Russian Federation

N. I. Zryachkin

Saratov State Medical University named after V.I. Razumovsky

Email: nizryach@yandex.ru
ORCID iD: 0000-0003-1953-0389

Nikolay I. Zryachkin – MD, PhD, Professor, Head of the Сhair of Pediatrics, Center of Continuing Professional Education

112 Bol'shaya Kazach'ya ul., Saratov, Saratovskaya oblast', 410012

Russian Federation

M. A. Kuznetsova

Saratov State Medical University named after V.I. Razumovsky

Email: kma1961@yandex.ru
ORCID iD: 0000-0003-4372-4132

Marina A. Kuznetsova – MD, PhD, Assistant Professor, Сhair of Pediatrics, Center of Continuing Professional Education

112 Bol'shaya Kazach'ya ul., Saratov, Saratovskaya oblast', 410012

Russian Federation

E. V. Bogacheva

Atkarsk District Hospital

Email: bogachevaev1958@yandex.ru

Ekaterina V. Bogacheva – MD, District Pediatrician of Child Welfare Clinic

23 Vali Makeevoy ul., Atkarsk, Saratovskaya oblast', 412423

Russian Federation


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Copyright (c) 2020 Tsareva J.A., Zryachkin N.I., Kuznetsova M.A., Bogacheva E.V.

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