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. 2024 Mar;15(2):156-160.
doi: 10.1159/000534932. Epub 2023 Nov 27.

A Rare Treatable Cause of Cardiomyopathy: Primary Carnitine Deficiency

Hacer Basan  1 , Emine Azak  2 , İbrahim İlker Çetin  2 , Esra Kiliç  3 , Berrak Bilginer Gürbüz  1 , Sümeyra Zeynep Özbey  1 , Çiğdem Seher Kasapkara  1
Affiliations

A Rare Treatable Cause of Cardiomyopathy: Primary Carnitine Deficiency

Hacer Basan et al. Mol Syndromol. 2024 Mar.

Abstract

Introduction: Primary carnitine deficiency (PCD) is a rare autosomal recessive disorder caused by loss of function mutations in the solute carrier family 22 member 5 (SLC22A5) gene that encodes a high-affinity sodium-ion-dependent organic cation transporter protein (OCTN2). Carnitine deficiency can result in acute metabolic decompensation or, in a more insidious presentation, cardiomyopathy. Cardiomyopathy associated with PCD often presents with life-threatening heart failure. This presentation also usually includes skeletal muscle myopathy. Early recognition of this disorder and treatment with carnitine can avoid life-threatening complications related to cardiomyopathy.

Case presentation: Herein, we present a 10-month-old male patient with PCD, which was diagnosed while investigating the etiology of dilated cardiomyopathy and confirmed by molecular genetic analysis.

Conclusion: Homozygous c.254_265 insGGCTCGCCACC (p.I89Gfs) pathogenic variant of the SLC22A5 gene was detected. With oral L-carnitine supplementation, the free carnitine level increased up to 14 μmol/L and the symptoms disappeared. LVEF increased by 45-70%. We would like to emphasize that this problem is a combination of the metabolic decompensation and the cardiac phenotypes, which are usually separated to either phenotype.

Keywords: Cardiomyopathy; Hyperammonemia; Primary carnitine deficiency; SLC22A5 mutation.

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Conflict of interest statement

The authors have no conflicts of interest to declare.

Figures

Fig. 1.
Fig. 1.
Transthoracic echocardiography before and after treatment with L-carnitine. a M-mode echocardiogram demonstrating enlarged left ventricle (LVDd 47 mm) with poor systolic function (LVEF 31%, LVKF 14%) on initial examination. b Left ventricle short axis. c M-mode echocardiography from a parasternal short-axis view with LV.
Fig. 2.
Fig. 2.
a After 4-month L-carnitine therapy, decreased LVEDD increased to left ventricle systolic function (LVEF 45%, KF 22%). b Left ventricle short axis. c M-mode echocardiography from a parasternal short-axis view with LV. LVEF, left ventricular ejection fraction; LVEDD, left ventricular end-diastolic diameter.
See this image and copyright information in PMC

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