Alsayed A, Albadrani M, Obaid A, Alhashim A, Alakkas A
Department of Neurology, National Neuroscience Institute, King Fahad Medical City, Riyadh, Saudi Arabia.
Alfaisal University, College of Medicine, Riyadh, Saudi Arabia.
Mol Genet Metab Rep. 2024 Aug 24;41:101135. doi: 10.1016/j.ymgmr.2024.101135. eCollection 2024 Dec.
L-2 hydroxyglutaric aciduria (L-2-HGA) is a rare autosomal recessive progressive, organic aciduria which presents with a wide variety of clinical manifestations. Diagnosis is complex and necessitates an increase in clinical suspicion of the disease to obtain the necessary diagnostic tests and thus early administration of appropriate management. In this case series, we are reporting three cases of patients with L-2-HGA who presented with a variety of clinical manifestations. All patients presented with a constellation of symptoms including febrile seizures, hyperactivity and intellectual difficulties. One case had an unusual presentation of cervical dystonia in early adulthood. Another case had a homozygous variant, : NM_024884.3: c.368 A > G p. (Tyr123Cys) classified as variant of uncertain significance (VUS) at that time but recently has been reclassified as likely pathogenic variant in clin var. Furthermore, brain MRI of two patients depicted characteristic signs consistent with L-2-HGA. The findings include, symmetrical confluent high T2/FLAIR signal intensity of the white matter involving the subcortical U fibers and deep white matter with sparing of the immediate periventricular white matter, internal capsules and corpus callosum. There was also symmetric abnormal T2 signal intensity of the caudate nuclei, lentiform nucleus as well as the dentate nuclei of the cerebellum. Overall, only few cases with similar genetic mutation have been documented in the literature and were of Saudi origin. The aim of the study is to highlight the clinico-radiological features of L-2-HGA to aid in early, prompt diagnosis, and thus appropriate follow up and management of the disease with riboflavin, levocarnitine and a low-lysine diet.
L-2-羟基戊二酸尿症(L-2-HGA)是一种罕见的常染色体隐性进行性有机酸尿症,临床表现多样。诊断复杂,需要提高对该疾病的临床怀疑,以进行必要的诊断测试,从而尽早给予适当治疗。在本病例系列中,我们报告了3例L-2-HGA患者,他们表现出各种临床表现。所有患者均出现一系列症状,包括热性惊厥、多动和智力障碍。1例在成年早期出现不寻常的颈部肌张力障碍表现。另1例有一个纯合变异:NM_024884.3:c.368 A>G p.(Tyr123Cys),当时被分类为意义未明的变异(VUS),但最近在clin var中被重新分类为可能的致病变异。此外,2例患者的脑部MRI显示出与L-2-HGA一致的特征性表现。这些表现包括,白质对称融合的高T2/FLAIR信号强度,累及皮质下U纤维和深部白质,紧邻脑室周围白质、内囊和胼胝体未受累。尾状核、豆状核以及小脑齿状核也有对称的异常T2信号强度。总体而言,文献中仅记载了少数具有相似基因突变的病例,且均来自沙特。本研究的目的是突出L-2-HGA的临床放射学特征,以帮助早期、及时诊断,并因此对该疾病进行适当的随访以及用核黄素、左卡尼汀和低赖氨酸饮食进行治疗。