Síndrome LPAC: relato de caso / LPAC syndrome: case report

Síndrome LPAC (Low Phospholipid-Associated Cholelithiasis) é uma enfermidade rara, que cursa com manifestações clínicas recorrentes relacionadas à litíase biliar, mesmo após colecistectomia em indivíduos jovens habitualmente com início dos sintomas antes dos 40 anos. Mutações no gene ABCB4 geram baixa concentração de fosfolipídios na secreção biliar, o que favorece a formação de cálculos de colesterol. Seu diagnóstico é estabelecido por critérios clínicos e o tratamento é fundamentado no uso do ácido ursodesoxicólico (UDCA). O objetivo deste artigo é relatar o caso de um paciente com síndrome LPAC.

Achalasia is an uncommon disorder that affects about LPAC syndrome (Low phospholipid-associated cholelithiasis) is a rare illness that leads to recurrent clinical manifestations related to gallstones, even after cholecystectomy in young individuals, usually with onset of symptoms before age 40. Mutations in the gene ABCB4 generate low concentration of phospholipids in bile secretion, which promotes the formation of cholesterol calculations. The diagnosis is established by clinical criteria and treatment is based on the use of ursodeoxycholic acid (UDCA). The objective of this paper is to report the case of a patient with LPAC syndrome.

Functional Characterization of ABCB4 Mutations Found in Low Phospholipid-Associated Cholelithiasis (LPAC)

Multidrug resistance 3 (MDR3) is expressed on the canalicular membrane of the hepatocytes and plays an important role in protecting the liver from bile acids. Altered ABCB4 gene expression can lead to a rare hepatic disease, low phospholipid-associated cholelithiasis (LPAC). In this study, we characterized 3 ABCB4 mutations in LPAC patients using various in vitro assay systems. We first measured the ability of each mutant to transport paclitaxel and then the mechanisms by which these mutations might change MDR3 transport activity were determined using immunoblotting, cell surface protein biotinylation, and immunofluorescence. Through a membrane vesicular transport assay, we observed that the uptake of paclitaxel was significantly reduced in membrane vesicles expressing 2 ABCB4 mutations, F165I and S320F. Both mutants showed significantly decreased total and cell surface MDR3 expression. These data suggest two missense mutations of ABCB4 may alter function of MDR3 and ultimately can be determined as LPAC-causing mutations.

Quantitative determination of LP(a)-C by agarose gel electrophoresis and its clinical application / 中华检验医学杂志

Objective To evaluate an agarose gel electrophoresis for quantitative determination of Lipoprotein(a) cholesterol and its clinical application.Methods Quantification of LP(a)-C was performed by a new agarose gel electrophoresis method that allows the separation of LP(a) by Hellen REP system and the determination of LP(a)-C by enzymatic staining of cholesterol,The results of electrophoresis method were compared with the ones of INA and ITA. The specimens of 135 health men were assayed by electrophoresis for the reference range.Results The inter and intra CV of electrophoresis method at low, middle and high LP(a) concentration specimens were 4.7%～5.3% and 5.8%～6.4%. The linearity was 0.058～1.55 mmol/L. Interference with bilirubin (