0
selected
-
1.
Clinical features and genetic analysis of childhood sitosterolemia: Two case reports and literature review.
Huang, D, Zhou, Q, Chao, YQ, Zou, CC
Medicine. 2019;(15):e15013
-
-
Free full text
-
Abstract
RATIONALE Sitosterolemia is a rare autosomal recessive disorder of dyslipidemia due to mutations of genes ABCG5 and ABCG8, leading to highly elevated plasma levels of plant sterols and expanded body pools of cholesterol. PATIENT CONCERNS We present a 9-year-old and a 7-year-old Chinese boy with hypercholesterolemia and xanthomas of sitosterolemia due to ABCG5 gene mutations. We also make a literature review of another 30 sitosterolemic children cases that have been reported with virulence ABCG5 gene mutations. DIAGNOSIS We took peripheral blood samples from 2 patients and their parents to conduct genetic analysis by next-generation sequencing (NGS) technologies. INTERVENTIONS The 2 patients received dietary modifications without pharmaceuticals treatment. OUTCOMES A c.1166G>A (Arg389His) homozygosis mutation in exon 9 was observed in case 1, whereas a c.751C>T (Gln251*) homozygosis mutation in exon 6 was found in case 2. Literature review found another 30 pediatric cases with sitosterolemia due to ABCG5 gene mutation. The lipid profile was normalized and xanthomas got smaller with combined therapy of a combined low-cholesterol and low-phytosterols diet. LESSONS These suggested that in patients (especially Asian patients) with multiple xanthomas, severe hypercholesterolemia, or elevated low-density lipoprotein-cholesterol, sitosterolemia should be considered in the differential diagnosis. Early diagnosis is important, and restriction of both cholesterol and phytosterols diet should suggested for these patients.
-
2.
Lp8 is potentially associated with partial lecithin:cholesterol acyltransferase deficiency in a patient with primary biliary cirrhosis.
Watanabe, T, Nema, T, Hiruta, N, Murano, T, Schneider, WJ, Bujo, H
Journal of clinical lipidology. 2018;(5):1157-1163
Abstract
BACKGROUND The significance of Lp8, that is, abnormal lipoprotein(s) detected in fraction 8 by combined high-performance liquid chromatography/gel filtration column in patients with familial lecithin:cholesterol acyltransferase (LCAT) syndrome, in relation to the severity of LCAT deficiency has not been analyzed. OBJECTIVE We have studied Lp8 in a patient with primary biliary cirrhosis. METHODS Plasma lipoproteins were analyzed using high-performance liquid chromatography/gel filtration column in the course of treatment of a 47-year-old female patient with primary biliary cirrhosis. RESULTS Electrophoretic lipoprotein analyses showed massive accumulation of abnormal ß- and preß-lipoproteins with a minor lipoprotein fraction at a position near the cathode corresponding to Lp-X, on day A (status: hypercholesterolemia, LCAT activity undetectable). Chromatographic lipoprotein subfraction analysis revealed free cholesterol- and phospholipid-rich lipoproteins in fractions 1-6, corresponding to chylomicrons and very low-density lipoprotein, and phospholipid- and triglyceride-rich lipoproteins with increased free cholesterol, that is, Lp8, in fractions 7-9 (corresponding to low-density lipoprotein). On day B, after additional treatment for 7 months (status: almost normolipidemia, decreased LCAT activity), although the abnormal lipoprotein and the lipoproteins in fractions 1-6, were drastically decreased, the presence of Lp8 persisted. CONCLUSIONS Lp8 likely is a minor abnormal lipoprotein fraction in patients with mildly decreased secondary LCAT activity, as well as with severely reduced primary LCAT activity.
-
3.
Timely diagnosis of sitosterolemia by next generation sequencing in two children with severe hypercholesterolemia.
Buonuomo, PS, Iughetti, L, Pisciotta, L, Rabacchi, C, Papadia, F, Bruzzi, P, Tummolo, A, Bartuli, A, Cortese, C, Bertolini, S, et al
Atherosclerosis. 2017;:71-77
Abstract
BACKGROUND AND AIMS Severe hypercholesterolemia associated or not with xanthomas in a child may suggest the diagnosis of homozygous autosomal dominant hypercholesterolemia (ADH), autosomal recessive hypercholesterolemia (ARH) or sitosterolemia, depending on the transmission of hypercholesterolemia in the patient's family. Sitosterolemia is a recessive disorder characterized by high plasma levels of cholesterol and plant sterols due to mutations in the ABCG5 or the ABCG8 gene, leading to a loss of function of the ATP-binding cassette (ABC) heterodimer transporter G5-G8. METHODS We aimed to perform the molecular characterization of two children with severe primary hypercholesterolemia. RESULTS Case #1 was a 2 year-old girl with high LDL-cholesterol (690 mg/dl) and tuberous and intertriginous xanthomas. Case #2 was a 7 year-old boy with elevated LDL-C (432 mg/dl) but no xanthomas. In both cases, at least one parent had elevated LDL-cholesterol levels. For the molecular diagnosis, we applied targeted next generation sequencing (NGS), which unexpectedly revealed that both patients were compound heterozygous for nonsense mutations: Case #1 in ABCG5 gene [p.(Gln251*)/p.(Arg446*)] and Case #2 in ABCG8 gene [p.(Ser107*)/p.(Trp361*)]. Both children had extremely high serum sitosterol and campesterol levels, thus confirming the diagnosis of sisterolemia. A low-fat/low-sterol diet was promptly adopted with and without the addition of ezetimibe for Case #1 and Case #2, respectively. In both patients, serum total and LDL-cholesterol decreased dramatically in two months and progressively normalized. CONCLUSIONS Targeted NGS allows the rapid diagnosis of sitosterolemia in children with severe hypercholesterolemia, even though their family history does not unequivocally suggest a recessive transmission of hypercholesterolemia. A timely diagnosis is crucial to avoid delays in treatment.
-
4.
Two novel variants of the ABCG5 gene cause xanthelasmas and macrothrombocytopenia: a brief review of hematologic abnormalities of sitosterolemia.
Bastida, JM, Benito, R, Janusz, K, Díez-Campelo, M, Hernández-Sánchez, JM, Marcellini, S, Girós, M, Rivera, J, Lozano, ML, Hortal, A, et al
Journal of thrombosis and haemostasis : JTH. 2017;(9):1859-1866
-
-
Free full text
-
Abstract
UNLABELLED Essentials Diagnosis of sitosterolemia, a rare recessive or syndromic disorder, is usually delayed. Peripheral blood smear is extremely useful for establishing the suspicion of sitosterolemia. High-throughput sequencing technology enables the molecular diagnosis of inherited thrombocytopenias. Accurate characterization of sitosterolemia helps us determine appropriate management. SUMMARY Background Sitosterolemia (STSL) is a recessive inherited disorder caused by pathogenic variants in the ABCG5 and ABCG8 genes. Increased levels of plasma plant sterols (PSs) usually result in xanthomas and premature coronary atherosclerosis, although hematologic abnormalities may occasionally be present. This clinical picture is unfamiliar to many physicians, and patients may be at high risk of misdiagnosis. Objectives To report two novel ABCG5 variants causing STSL in a Spanish patient, and review the clinical and mutational landscape of STSL. Patient/Methods A 46-year-old female was referred to us with lifelong macrothrombocytopenia. She showed familial hypercholesterolemia-related xanthomas. Molecular analysis was performed with high-throughput sequencing. Plasma PS levels were evaluated with gas-liquid chromatography. The STSL landscape was reviewed with respect to specific online databases and all reports published since 1974. Results A blood smear revealed giant platelets and stomatocytes. Novel compound heterozygous variants were detected in exons 7 (c.914C>G) and 13 (c.1890delT) of ABCG5. The patient showed an increased plasma level of sitosterol. These findings support the diagnosis of STSL. In our review, we identified only 25 unrelated STLS patients who presented with hematologic abnormalities including macrothrombocytopenia. It remains unknown why only some patients develop hematologic abnormalities. Conclusions This is the first Spanish STSL patient to be reported and molecularly characterized. The early diagnosis of STLS is strongly supported by the presence of stomatocytes in blood smears. The definitive diagnosis of STSL by measurement of serum PS levels and molecular analyses prompted the use of ezetimibe therapy.
-
5.
Subfraction analysis of circulating lipoproteins in a patient with Tangier disease due to a novel ABCA1 mutation.
Murano, T, Yamaguchi, T, Tatsuno, I, Suzuki, M, Noike, H, Takanami, T, Yoshida, T, Suzuki, M, Hashimoto, R, Maeno, T, et al
Clinica chimica acta; international journal of clinical chemistry. 2016;:167-72
Abstract
Tangier disease, characterized by low or absent high-density lipoprotein (HDL), is a rare hereditary lipid storage disorder associated with frequent, but not obligatory, severe premature atherosclerosis due to disturbed reverse cholesterol transport from tissues. The reasons for the heterogeneity in atherogenicity in certain dyslipidemias have not been fully elucidated. Here, using high-performance liquid chromatography with a gel filtration column (HPLC-GFC), we have studied the lipoprotein profile of a 17-year old male patient with Tangier disease who to date has not developed manifest coronary atherosclerosis. The patient was shown to be homozygous for a novel mutation (Leu1097Pro) in the central cytoplasmic region of ATP-binding cassette transporter A1 (ABCA1). Serum total and HDL-cholesterol levels were 59mg/dl and 2mg/dl, respectively. Lipoprotein electrophoretic analyses on agarose and polyacrylamide gels showed the presence of massively abnormal lipoproteins. Further analysis by HPLC-GFC identified significant amounts of lipoproteins in low-density lipoprotein (LDL) subfractions. The lipoprotein particles found in the peak subfraction were smaller than normal LDL, were rich in triglycerides, but poor in cholesterol and phospholipids. These findings in an adolescent Tangier patient suggest that patients in whom these triglyceride-rich, cholesterol- and phospholipid-poor LDL-type particles accumulate over time, would experience an increased propensity for developing atherosclerosis.