Two novel variants in the lecithin:cholesterol acyltransferase gene resulted in classic LCAT deficiency

Margareta Fistrek Prlic; Marijana Coric; Laura Calabresi; Chiara Pavanello; Lorena Mosca; Ugo Cavallari; Ivana Vukovic Brinar; Sandra Karanovic; Mario Laganovic; Bojan Jelakovic

doi:10.1016/j.athplu.2022.05.005

Two novel variants in the lecithin:cholesterol acyltransferase gene resulted in classic LCAT deficiency

Atheroscler Plus. 2022 Jun 2:49:28-31. doi: 10.1016/j.athplu.2022.05.005. eCollection 2022 Aug.

Authors

Affiliations

¹ Department of Nephrology, Arterial Hypertension, Dialysis and Transplantation, University Hospital Center Zagreb, University of Zagreb, School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia.
² Department of Pathology, University Hospital Center Zagreb, University of Zagreb, School of Medicine, Kispaticeva 12, 10000, Zagreb, Croatia.
³ Center E. Grossi Paoletti, Department of Pharmacology, University of Milan, Via Balzaretti 9, 20133, Milan, Italy.
⁴ Medical Genetics Unit, Department of Services, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162, Milan, Italy.
⁵ Department of Nephrology, University Hospital Merkur, University of Zagreb, School of Medicine, Zajceva 19, 10000, Zagreb, Croatia.

Abstract

Background and aims: We report the first two cases of familial lecithin:cholesterol acyltransferase (LCAT) deficiency in Croatia with classical clinical and biochemical features.

Patients and methods: A 30-year-old man with nephrotic syndrome, corneal opacities, hepatosplenomegaly, anemia, low high-density lipoprotein (HDL)-cholesterol levels and arterial hypertension (blood pressure >200/100 mmHg) was admitted to our department. At admission, he had an elevated creatinine serum level (233 μmol/L), proteinuria of 12 g in 24-h urine (g/24 h), 3-7 erythrocytes in urine sediment and notable anemia (hemoglobin level 90 g/l). His HDL-cholesterol was significantly low (0.42 mmol/L). Besides chronic kidney disease (CKD), other secondary causes of hypertension were ruled out. The patient was previously diagnosed with membranous nephropathy and treated unsuccessfully with immunosuppressive agents (steroids, cyclosporine, cyclophosphamide). Re-evaluation of histopathological findings of kidney biopsy revealed massive deposition of lipid material in the glomerular basal membrane and in the mesangial region. His 4-year younger brother was also evaluated due to corneal opacities and new-onset arterial hypertension. Nephrotic range proteinuria with preserved global renal function was determined. He also had very low HDL-cholesterol levels.

Results: Kidney biopsies from both patients were consistent with LCAT deficiency. The disease was confirmed by measurement of LCAT enzyme activity, plasma cholesterol esterification rate, and genetic testing. Two novel missense variants in the LCAT gene (c.496G > A and c.1138T > C) were found.

Conclusions: To our knowledge, the presented cases are the first reported cases of genetic LCAT deficiency in Croatia. Given the clinical presentation, the complete lack of LCAT activity and cholesterol esterification rate, diagnosis of familial LCAT deficiency was made.

Keywords: Gene variants; LCAT deficiency; LCAT gene; Nephrotic syndrome.