[Full text] Transiently Elevated TC and sdLDL-C Levels and Falsely Low LDL-C Level

Plain Language Abstract

Serum lipid exams on the division of laboratory drugs embody complete ldl cholesterol (TC), triglycerides (TG), high-density lipoprotein ldl cholesterol (HDL-C), low-density lipoprotein ldl cholesterol (LDL-C), apolipoprotein A (apoA), apolipoprotein B (apoB), lipoprotein (a) (Lp (a)), and small and dense LDL-C (sdLDL-C). Usually, TC values are positively correlated with LDL-C values. As well as, LDL-C values ought to be higher than sdLDL-C values. Nevertheless, we lately observed a affected person with extrahepatic cholangiocarcinoma (ECCA) who exhibited biliary obstruction and cholestasis, confirmed exceptionally excessive ranges of TC (17.14 mmol/L) and sdLDL-C (15.262 mmol/L), and abnormally low ranges of LDL-C (0.48 mmol/L). Clinicians within the Division of Hepatobiliary Surgical procedure requested whether or not they need to prescribe the affected person lipid-lowering medicines after reviewing these diagnostic outcomes. Nevertheless, no earlier systematic analysis has been carried out that surveyed the adjustments in lipid parameters in sufferers with ECCA. Subsequently, this research was designed to discover adjustments in lipid profiles in sufferers with ECCA and to analyze whether or not biliary obstruction and cholestasis reduction may right irregular serum lipid ranges. Our information confirmed that sufferers with ECCA had transiently elevated ranges of TC and sdLDL-C and falsely low LDL-C outcomes. TC, sdLDL-C, and LDL-C ranges might be recovered to regular ranges after biliary obstruction and cholestasis reduction. Subsequently, it isn’t mandatory for sufferers with ECCA to manage hypercholesterolemia by taking lipid-lowering treatment.

Introduction

Cholangiocarcinoma (CCA) is the second most typical major hepatobiliary malignancy, contributing to just about 20% of hepatobiliary most cancers deaths.¹ CCA is usually categorised into two teams, together with intrahepatic CCA (ICCA), which happens within the bile duct space contained in the liver, and extrahepatic CCA (ECCA), which happens within the bile duct space exterior the liver.² ICCA accounts for 10% to 12% of liver cancers, whereas ECCA accounts for roughly 1/3 of all biliary tract cancers.^3,4 The incidence price of ECCA has decreased in most developed international locations,⁵ however latest will increase in ECC incidence have been noticed in China.⁶

The scientific presentation of ICCA is commonly refined and should manifest as non-specific signs corresponding to weight reduction, vomiting, and lack of urge for food.⁷ In distinction, ECCA is often accompanied by jaundice because of biliary tract obstruction.⁸ Elevated water-soluble conjugated bilirubin ranges may be filtered by the kidney, leading to darker coloured urine.⁹ Furthermore, bilirubin doesn’t go into the duodenum in circumstances of an obstructed biliary tract, and ECCA affected person feces are often white or white-yellowish of colour.¹⁰ After relieving cholestasis utilizing surgical resection or palliative therapy in sufferers with ECCA, signs together with yellow pigmentation of the pores and skin, mucous membranes and sclera, darkish urine, and acholic/pale stools could disappear.^11,12

Cholestasis brought on by the bile duct’s obstruction is especially chargeable for the indicators and signs talked about above.¹³ Furthermore, cholestasis could result in a rise of some laboratory indices corresponding to complete bile acid (TBA), alkaline phosphatase (ALP), and gamma-glutamyltranspeptidase (GGT).⁸ Lipid metabolic problems are additionally reported in some sufferers with cholestasis, in whom hypercholesterolemia and irregular ranges of low-density lipoprotein ldl cholesterol (LDL-C) are noticed.^14,15 Not too long ago, we discovered related lipometabolic disturbances in sporadic circumstances with ECCA. Of specific concern is whether or not such sufferers ought to be handled with lipid-lowering treatment. Nevertheless, no systematic analysis has been carried out to evaluate adjustments in lipid parameters in sufferers with ECCA.

Subsequently, this potential research was designed to discover serum the change of lipid indices in sufferers with ECCA and examine whether or not elimination of biliary obstruction may alleviate the lipid dysfunction.

Strategies

Members and Research Design

We prospectively included consecutive sufferers admitted to the hepatobiliary surgical procedure division of the Affiliated Hospital of Xuzhou Medical College from October 2019 to Might 2020. The sufferers acquired a scientific analysis on admission, together with medical historical past, bodily examination, blood exams, and imaging exams. Based mostly on the illness evaluation, sufferers have been divided into an ECCA group or a non-ECCA group for additional prognosis. ECCA was outlined as a tumor originating within the bile duct exterior the liver. Sufferers with histological affirmation by endoscopic or surgical specimen have been lastly included within the ECCA group. Sufferers with hemolytic jaundice, hepatocellular jaundice, pancreatitis, diabetes mellitus, arterial hypertension, and coronary coronary heart illness have been excluded. Particular standards for obstructive jaundice have been as follows: (1) scientific indicators of icterus (yellow-stained pores and skin, mucosa, and sclera, yellow urine or clay-colored stools), (2) elevated serum complete bilirubin concentrations (cut-off worth=34.2 μmol/L), and (3) bile duct dilatation confirmed by imaging examination (ultrasonography, CT or MRCP).

Specimen Assortment and Biochemical Exams

Blood samples have been collected from peripheral veins on admission and 5 days after therapy. After in a single day fasting, 5 mL of blood was collected into serum-separating tubes for liver perform and serum lipid detection. An automated biochemistry analyzer (Roche^® Cobas 8000, Roche Diagnostics, Indianapolis, IN, USA) was used to check liver perform and measure serum lipid ranges utilizing spectrophotometry. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), prealbumin (PA), complete protein (TP), albumin (ALB), complete bilirubin (TBIL), bilirubin direct (DBIL), complete bile acid (TBA), complete ldl cholesterol (TC), triglycerides (TG) and cholinesterase (CHE) have been detected utilizing industrial kits (Roche Diagnostic, Indianapolis, IN, USA). Excessive-density lipoprotein ldl cholesterol (HDL-C), low-density lipoprotein ldl cholesterol (LDL-C), apolipoprotein A (apoA), apolipoprotein B (apoB), and lipoprotein (a) (Lp (a)) have been examined utilizing industrial kits (Zhicheng Organic Expertise Co., Ltd., Shanghai, China). Small and dense low-density lipoprotein ldl cholesterol (sdLDL-C) was measured utilizing a equipment produced by Yipunuokang Biotechnology Co., Ltd. (Anhui, China).

Lipoprotein electrophoresis was carried out to find out the distribution of lipoprotein parts. Serum lipoproteins have been stained with Sudan black B (quantity ratio 1:1) for 30 min at room temperature. Combined samples (15μL) have been separated utilizing a 5% agarose gel and barbitone sodium buffer (ph=8.6) at 180V for 20 min.

Knowledge Assortment

Each private and scientific information have been collected from sufferers included within the research. Private information included intercourse and age. Scientific information included prognosis, therapy, indicators of jaundice, and imaging proof.

Statistical Evaluation

Statistical evaluation was carried out utilizing SPSS (model 23.0, SPSS Inc., Chicago, IL, USA). Steady variables with regular distributions have been expressed as imply ± normal deviation and analyzed utilizing unbiased pattern t-tests, whereas these with skewed distribution have been proven because the median (Q1, Q3) and analyzed utilizing Mann–Whitney exams or Wilcoxon exams.

Outcomes

Affected person Traits

100 and eighty sufferers met the inclusion standards and have been enrolled within the research. A complete of 76 sufferers have been recognized with ECCA after histological analysis. Amongst these sufferers, 41 (54.0%) have been recognized with proximal cholangiocarcinoma, 9 (11.8%) with center cholangiocarcinoma, and 26 (34.2%) with distant cholangiocarcinoma. Within the ECCA group, 69 sufferers underwent radical resection, together with 1 (1.3%) in stage 0, 6 (7.9%) in stage I, 11 (14.5%) in stage II, and 51 (67.1%) in stage III. The opposite seven sufferers have been in stage IV, and underwent percutaneous transhepatic biliary drainage and stenting for palliative therapy. We enrolled 104 sufferers within the non-ECCA group. Amongst these sufferers, 37 have been recognized with choledocholithiasis, 3 with cholangitis, 53 with cholecystolithiasis, 9 with cholecystitis, and a pair of with cholecystic polypus. Within the non-ECCA group, 64 sufferers underwent cholecystectomy, and 40 underwent widespread bile duct exploration and T-tube drainage. Vital variations have been recognized within the variety of jaundice circumstances (P <0.01) between the 2 teams. There was no vital distinction in gender or age between the 2 teams (P > 0.05). Particulars are proven in Table 1.

Desk 1 Demographics and Scientific Traits of the Research Inhabitants

Serum Lipid Ranges Variations within the ECCA versus Non-ECCA Teams Earlier than Remedy

We collected 360 blood samples, of which 180 samples have been obtained earlier than therapy and 180 samples after therapy. Earlier than therapy, GGT, ALP, TBIL, DBIL, and TBA ranges have been considerably increased within the ECCA group than within the non-ECCA group (P <0.01) (Table 2). TC ranges have been considerably increased within the ECCA group than within the non-ECCA group (5.70 [4.82, 7.40] mmol/L vs 4.17 [3.53, 5.06] mmol/L, P <0.01) (Table 2, Figure 1A). Correspondingly, the ECCA group confirmed considerably increased ranges of sdLDL-C in contrast with the non-ECCA group (1.633 [1.043, 3.072] mmol/L vs 0.980 [0.641, 1.329] mmol/L, P <0.01) (Table 2, Figure 1E). Unexpectedly, the degrees of LDL-C have been barely decrease within the ECCA group than within the non-ECCA group. (1.97 [0.92, 2.84] mmol/L vs 2.13 [1.69, 2.85] mmol/L, P = 0.04) (Table 2, Figure 1C). Virtually all sufferers within the ECCA group exhibited obstructive jaundice. Within the non-ECCA group, 28 sufferers confirmed biliary obstruction, together with 26 with choledocholithiasis, 2 with cholecystolithiasis, and 1 with cholecystitis. Greater TC ranges (P <0.01) and sdLDL-C ranges (P <0.01) have been noticed within the ECCA group than within the biliary obstruction circumstances within the non-ECCA group (Figure 1B and F). No vital distinction was noticed in LDL-C ranges (P = 0.13) between the 2 teams (Figure 1D). The agreements between TC and sdLDL-C have been good in each teams (P <0.01) (Figure 2A and C). The correlations between TC and LDL-C within the non-ECCA group have been robust (Figure 2D), however no vital correlations have been noticed between TC and LDL-C within the ECCA group (P =0.16) (Figure 2B).

Desk 2 Liver Perform and Serum Lipid Indices of the Sufferers Earlier than Remedy

Determine 1 The degrees of TC, LDL-C and sdLDL-C in sufferers earlier than therapy. Abbreviations: ECCA, extrahepatic cholangiocarcinoma; TC, complete ldl cholesterol; LDL-C, low-density lipoprotein ldl cholesterol; sdLDL-C, small and dense low-density lipoprotein ldl cholesterol. Notes: (A) Comparability of ranges of TC between the ECCA group and the non-ECCA group. (B) Comparability of ranges of TC between the ECCA group and biliary obstruction circumstances the non-ECCA group. (C) Comparability of ranges of LDL-C between the ECCA group and the non-ECCA group. (D) Comparability of ranges of LDL-C between the ECCA group and biliary obstruction circumstances the non-ECCA group. (E) Comparability of ranges of sdLDL-C between the ECCA group and the non-ECCA group. (F) Comparability of ranges of sdLDL-C between the ECCA group and biliary obstruction circumstances the non-ECCA group.

Determine 2 Correlation of serum lipid indices in sufferers earlier than therapy. Abbreviations: ECCA, extrahepatic cholangiocarcinoma; TC, complete ldl cholesterol; LDL-C, low-density lipoprotein ldl cholesterol; sdLDL-C, small and dense low-density lipoprotein ldl cholesterol. Notes: (A) Correlation of sdLDL-C values and TC values within the ECCA group. (B) Correlation of LDL-C values and TC values within the ECCA group. (C) Correlation of sdLDL-C values and TC values within the non-ECCA group. (D) Correlation of LDL-C values and TC values within the non-ECCA group.

Serum Lipoprotein Electrophoresis

Lipoprotein electrophoresis was carried out to analyze the explanations for comparatively low LDL-C ranges within the ECCA group. Lipoproteins in regular serum can primarily be separated into two components: LDL and HDL particles (Figure 3A–H). Within the ECCA group, serum samples have been detained within the pattern wells and lipoproteins did not separate, suggesting these lipoprotein particles have been irregular (Figure 3A–H). Subsequently, cholestasis brought on by jaundice could also be attributed to the formation of irregular lipoproteins, which then have an effect on LDL-C detection in biochemistry exams.

Determine 3 The serum lipoprotein electrophoresis outcomes of 8 ECCA sufferers who had sometimes irregular LDL-C values. Observe: (A–H) Comparability of serum lipoprotein electrophoresis between non-ECCA sufferers (management) and ECCA sufferers earlier than and after therapy.

Serum Lipid Ranges within the ECCA Group After Remedy

The degrees of GGT, ALP, TBIL, DBIL, and TBA dramatically decreased within the ECCA group after therapy (P <0.01) (Table 3), suggesting that cholestasis was relieved. Vital variations remained in liver perform indices between the ECCA group and the non-ECCA group after therapy (P <0.01) (Table 3). The degrees of TC and sdLDL-C considerably decreased after therapy within the ECCA group (Table 3, Figure 4A, C, and E). The median TC ranges within the ECCA group earlier than therapy and after therapy have been 5.70 (4.82, 7.40) and three.81 (2.88, 4.57), respectively (P <0.01). The median sdLDL-C ranges within the two group have been 1.633 (1.043, 3.072) and 0.830 (0.551, 1.231), respectively (P <0.01). Most sufferers within the ECCA group confirmed regular ranges of TC and sdLDL-C after therapy, and there have been no vital variations in TC and sdLDL-C ranges between the ECCA and the non-ECCA teams after therapy (Table 3, Figure 4B, D, and F). Lipoprotein electrophoresis outcomes revealed that sufferers with ECCA who had serum LDL particles that didn’t separate confirmed a traditional lipoprotein sample after therapy (Figure 3A–H).

Desk 3 Liver Perform and Serum Lipid Indices of the Sufferers After Remedy

Determine 4 The degrees of TC, LDL-C and sdLDL-C in sufferers after therapy. Notes: (A) Comparability of ranges of TC within the ECCA group between earlier than and after therapy. (B) Comparability of ranges of TC between the ECCA group and the non-ECCA group after therapy. (C) Comparability of ranges of LDL-C within the ECCA group between earlier than and after therapy. (D) Comparability of ranges of LDL-C between the ECCA group and the non-ECCA group. (E) Comparability of ranges of sdLDL-C within the ECCA group between earlier than and after therapy. (F) Comparability of ranges of sdLDL-C between the ECCA group and the non-ECCA group after therapy.

Dialogue

Serum lipid is the final identify of lipids within the blood, primarily together with triglycerides (TG), ldl cholesterol (CH), and phospholipids (PL). CH contains free ldl cholesterol and ldl cholesterol esters, that are collectively known as complete ldl cholesterol (TC). Since TG and TC are hydrophobic substances, they need to kind hydrophilic spherical particles with specific proteins and phospholipids, known as lipoproteins, to permit transport within the blood.16 Because of the totally different constructions and numerous compositions, lipoproteins may be divided into chylomicron, very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) by ultracentrifugation. In agarose gel electrophoresis, it may be separated as chylomicron, β-lipoprotein, which corresponds to LDL in ultracentrifugation, and α-lipoprotein, which corresponds to HDL, from cathode to anode. LDL’s major perform is to move the endogenous ldl cholesterol synthesized by the liver to the extrahepatic tissue.¹⁷ Subsequently, the extent of ldl cholesterol in LDL (LDL-C) often is positively correlated with the extent of TC. LDL may be additional segmented into many subtypes by way of ultracentrifugation, corresponding to small and dense LDL (sdLDL). Subsequently, the extent of sdLDL-C would sometimes be decrease than the extent of LDL-C. On this research, we discovered that sufferers with ECCA had elevated TC and sdLDL-C ranges, and falsely offered with decreased LDL-C ranges at admission. We additionally firstly demonstrated that the TC, sdLDL-C, and LDL-C ranges return to regular ranges after biliary obstruction elimination and cholestasis reduction.

A number of research have proven that lipid metabolic problems are a typical complication of cholestasis.^14,18 Basaranoglu et al reported that sufferers with intrahepatic cholestasis had a considerably increased TC degree than wholesome controls (P <0.01),¹⁹ just like our outcomes. The TC and sdLDL-C ranges have been considerably elevated in sufferers with ECCA, who often present extra apparent biliary obstruction and cholestasis. It has additionally been demonstrated that cholestasis, brought on by the injection of sodium taurolithocholate, results in elevated quantities of ldl cholesterol particles within the hepatocytic cytoplasm and the biliary canaliculi of a mouse mannequin.²⁰ In contrast with sufferers with acute cholestasis brought on by benign ailments, sufferers with ECCA had increased ranges of TC and sdLDL-C, suggesting that hypercholesterolemia is extra obvious and extreme in persistent cholestasis. Hypercholesterolemia noticed in cholestasis is especially associated to the presence of an anomalous lipoprotein named lipoprotein-X (Lp-X). Within the obstructive biliary tract, a lipoprotein could reflux into the blood vessels with bile, combine with TC, apo-C, and esterified ldl cholesterol, to turn out to be “mature” Lp-X.²¹ This lipoprotein may improve the exercise of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, and improve hepatic ldl cholesterol synthesis.¹⁸

Surprisingly, we discovered that LDL-C ranges have been considerably decreased within the ECCA affected person group in contrast with the management group. We observed that some sufferers with ECCA confirmed irregular LDL-C ranges, which will be the cause for the sudden outcomes. The Friedewald system [(LDL-C) = TC – (HDL-C) -TG/2.2 mmol/L] was used to estimate LDL-C values.²² Nevertheless, the LDL-C values straight quantified by the automated biochemical analyzer and people calculated based on the Friedewald system didn’t match in some sufferers with ECCA. One other discrepancy was that LDL-C values in these sufferers have been decrease than the sdLDL-C values. Since sdLDL is a subtype of LDL, LDL-C values ought to be higher than sdLDL-C values. Usually, LDL-C is measured utilizing homogeneous strategies, the place membranes of LDL particles ought to be firstly dissolved by a selected surfactant, after which ldl cholesterol launched from LDL particles may be quantified utilizing coupling response of ldl cholesterol esterase, ldl cholesterol oxidase, and peroxidase.¹⁵ Regular LDL particles ought to transfer ahead within the electrophoresis, however lipoproteins in sufferers with ECCA remained within the sampling wells.²³ These outcomes recommend that physicochemical properties of LDL particles have been altered, stopping the surfactant from dissolving the particle membranes, leading to massive quantities of LDL-C did not be detected. Along with the robust correlation between TC and sdLDL-C, we thought-about the irregular LDL-C ranges noticed in sufferers with ECCA to be falsely low. Garcia-Hejl et al²² additionally thought-about a case of low LDL-C in a 69-year-old male with kind IIa dyslipidemia as false. That research discovered a discrepancy between the TC worth (9.18 mmol/L) and the sum of the direct LDL-C (3.55 mmol/L) and HDL-C values (0.27 mmol/L). Lp-X current in cholestasis could intervene with homogenous assays for LDL-C measurements, resulting in misinterpretation of the lipid standing in sufferers with ECCA.²⁴

Thankfully, dyslipidemia in sufferers with ECCA may be corrected. We detected no vital variations in TC and sdLDL-C noticed between the ECCA and the management teams after relieving obstructions. In distinction, indicators of bile duct obstruction (corresponding to GGT and ALP) didn’t rapidly lower, since GGT and ALP ranges could dramatically improve in sufferers affected by malignant biliary obstruction. This improve is often discovered to be ten occasions increased than the higher limits of the reference ranges. The irregular electrophoresis outcomes disappeared after therapy. Different research have additionally reported that anomalous LDL-C quickly decreases after surgical elimination of biliary obstruction, and hypercholesterolemia brought on by cholestasis has not been discovered related to vascular danger.^25,26 These outcomes recommend that sufferers with ECCA don’t must take lipid-lowering medicines, corresponding to statins, for hypercholesterolemia. Subsequently, our research holds the potential for avoiding extreme therapies, decreasing drug dependence and lowering medical bills.

Since Lp-X performs a necessary function within the prevalence and growth of hypercholesterolemia of cholestasis, the analysis pursuits on this space within the subsequent 5 years ought to deal with figuring out the constructions and compositions of the irregular lipoprotein particle. Based mostly on such information, industrial kits for testing Lp-X can then be developed. The Lp-X take a look at could also be helpful to deduce cholestasis in sufferers with liver abnormalities of unsure origin, and should point out the therapeutic results and prognosis of sufferers with malignant biliary obstruction.

Regardless of our findings and promising prospects, the research did have some limitations. First, the irregular lipoprotein in sufferers with ECCA has not been recognized within the scientific assay because it couldn’t be separated utilizing electrophoresis. Second, dyslipidemia will not be an unique characteristic for ECCA; different ailments concerned within the persistent bile duct obstruction may current as lipid problems. Third, the relevance between cholestasis reduction and dyslipidemia corrections must be additional validated with a bigger pattern dimension, for this research solely included an Asian inhabitants.

Conclusion

ECCA sufferers confirmed transiently elevated sdLDL-C and TC ranges and falsely offered with low LDL-C outcomes. TC, sdLDL-C, and LDL-C ranges have been restored to regular ranges after biliary obstruction elimination and cholestasis reduction.

Ethics Approval and Knowledgeable Consent

The research was authorised by the Establishment Ethics Overview Board for Human Research within the Affiliated Hospital of Xuzhou Medical College. The research was carried out in accordance with the rules of the Declaration of Helsinki. Written knowledgeable consent was supplied by all taking part sufferers.

Acknowledgments

We’re sincerely grateful to Ping Ma and Shi-Bao Li from the Division of Laboratory Drugs, Affiliated Hospital of Xuzhou Medical College, who helped us to revise the manuscript.

Creator Contributions

Yi Guo contributed to the research design, and wrote the primary manuscript textual content. Yong-Gen Zhang carried out the primary experiments, and contributed to statistical evaluation. Hong-Chun Li appeared up the medical information and conceived the research. Yin-Hai Xu was take part within the conception, communicated with the scientific medical doctors, collected samples, and revised the manuscript. The entire authors reviewed the manuscript. All authors contributed to information evaluation, drafting or revising the article, have agreed on the journal to which the article will probably be submitted, gave last approval of the model to be revealed, and conform to be accountable for all features of the work.

Funding

This work was supported by Analysis Begin-up Fund for expertise introduction within the Affiliated Hospital of Xuzhou Medical College (Grant No. 2020203002) and the Basis Analysis Undertaking (Pure Science Fund) of Jiangsu Province (Grant No. BK20201013).

Disclosure

The authors report no conflicts of curiosity on this work.

References

1. Everhart JE, Ruhl CE. Burden of digestive ailments in the US Half III: liver, biliary tract, and pancreas. Gastroenterology. 2009;136(4):1134–1144. doi:10.1053/j.gastro.2009.02.038

2. Massa A, Varamo C, Vita F, et al. Evolution of the experimental fashions of cholangiocarcinoma. Cancers (Basel). 2020;12(8):2308. doi:10.3390/cancers12082308

3. Altekruse SF, Devesa SS, Dickie LA, McGlynn KA, Kleiner DE. Histological classification of liver and intrahepatic bile duct cancers in SEER registries. J Registry Manag. 2011;38(4):201–205.

4. Van Dyke AL, Shiels MS, Jones GS, et al. Biliary tract most cancers incidence and traits in the US by demographic group, 1999–2013. Most cancers. 2019;125(9):1489–1498. doi:10.1002/cncr.31942

5. Bertuccio P, Malvezzi M, Carioli G, et al. International traits in mortality from intrahepatic and extrahepatic cholangiocarcinoma. J Hepatol. 2019;71(1):104–114. doi:10.1016/j.jhep.2019.03.013

6. Florio AA, Ferlay J, Znaor A, et al. International traits in intrahepatic and extrahepatic cholangiocarcinoma incidence from 1993 to 2012. Most cancers. 2020;126(11):2666–2678. doi:10.1002/cncr.32803

7. Moazzami B, Majidzadeh AK, Dooghaie-Moghadam A, et al. Cholangiocarcinoma: cutting-edge. J Gastrointest Most cancers. 2020;51(3):774–781. doi:10.1007/s12029-020-00390-3

8. Forner A, Vidili G, Rengo M, Bujanda L, Ponz-Sarvise M, Lamarca A. Scientific presentation, prognosis and staging of cholangiocarcinoma. Liver Int. 2019;39 Suppl 1:98–107. doi:10.1111/liv.14086

9. Gondal B, Aronsohn A, Systematic A. Method to sufferers with jaundice. Semin Intervent Radiol. 2016;33(4):253–258. doi:10.1055/s-0036-1592331

10. Sullivan JI, Rockey DC. Analysis and analysis of hyperbilirubinemia. Curr Opin Gastroenterol. 2017;33(3):164–170. doi:10.1097/MOG.0000000000000354

11. Abu-Hamda EM, Baron TH. Endoscopic administration of cholangiocarcinoma. Semin Liver Dis. 2004;24(2):165–175. doi:10.1055/s-2004-828893

12. Esnaola NF, Meyer JE, Karachristos A, Maranki JL, Camp ER, Denlinger CS. Analysis and administration of intrahepatic and extrahepatic cholangiocarcinoma. Most cancers. 2016;122(9):1349–1369.

13. Rizzo A, Ricci AD, Frega G, et al. How to decide on between percutaneous transhepatic and endoscopic biliary drainage in malignant obstructive jaundice: an up to date systematic overview and meta-analysis. In Vivo (Brooklyn). 2020;34(4):1701–1714. doi:10.21873/invivo.11964

14. Fellin R, Manzato E. Lipoprotein-X fifty years after its unique discovery. Nutr Metab Cardiovasc Dis. 2019;29(1):4–8. doi:10.1016/j.numecd.2018.09.006

15. Kurosawa H, Yoshida H, Yanai H, Ogura Y, Hirowatari Y, Tada N. Comparative research between anion-exchange HPLC and homogeneous assay strategies in regard to the accuracy of high- and low-density lipoprotein ldl cholesterol measurement. Clin Biochem. 2007;40(16–17):1291–1296. doi:10.1016/j.clinbiochem.2007.07.008

16. Feingold KR, Grunfeld C. Introduction to Lipids and Lipoproteins. In: Feingold KR, Anawalt B, Boyce A, editors. Endotext. South Dartmouth (MA): MDText.com, Inc. 2000; 22–33.

17. Beisiegel U. Lipoprotein metabolism. Eur Coronary heart J. 1998;19 Suppl A:A20–A23.

18. Nuno-Lambarri N, Barbero-Becerra VJ, Uribe M, Chavez-Tapia NC. Elevated levels of cholesterol have a poor prognosis in a cholestasis situation. J Biochem Mol Toxicol. 2017;31(1):1–6. doi:10.1002/jbt.21831

19. Basaranoglu S, Agacayak E, Ucmak F, et al. The function of vitamin B1-B2 and plasma lipid profile in intrahepatic cholestasis of being pregnant. J Perinat Med. 2017;45(4):461–465. doi:10.1515/jpm-2015-0337

20. Bonvicini F, Gautier A, Gardiol D, Borel GA. Ldl cholesterol in acute cholestasis induced by taurolithocholic acid. A cytochemical research in transmission and scanning electron microscopy. Lab Make investments. 1978;38(4):487–495.

21. Manzato E, Fellin R, Baggio G, Walch S, Neubeck W, Seidel D. Formation of lipoprotein-X. Its relationship to bile compounds. J Clin Make investments. 1976;57(5):1248–1260. doi:10.1172/JCI108393

22. Garcia-Hejl C, Vest P, Renard C, Merens-Gonthier A, Boukhira A, Thefenne-Astier H. Falsely low LDL ldl cholesterol outcomes and cholestasis. Clin Chem. 2006;52(11):2125–2127. doi:10.1373/clinchem.2006.072249

23. Kattah L, Gomez A, Gutierrez S, et al. Hypercholesterolemia because of Lipoprotein X: case report and thematic overview. Clin Med Insights Endocrinol Diabetes. 2019;12:1179551419878687. doi:10.1177/1179551419878687

24. Heimerl S, Boettcher A, Kaul H, Liebisch G. Lipid profiling of lipoprotein X: implications for dyslipidemia in cholestasis. Biochim Biophys Acta. 2016;1861(8 Pt A):681–687. doi:10.1016/j.bbalip.2016.04.016

25. Frohlich J. Function of lecithin: ldl cholesterol acyltransferase and apolipoprotein A-I in ldl cholesterol esterification in lipoprotein-X in vitro. J Lipid Res. 1995;36(11):2344–2354. doi:10.1016/S0022-2275(20)39715-7

26. Allocca M, Crosignani A, Gritti A, et al. Hypercholesterolaemia shouldn’t be related to early atherosclerotic lesions in major biliary cirrhosis. Intestine. 2006;55(12):1795–1800. doi:10.1136/intestine.2005.079814