Precipitation Of Calcium Salts Research Articles

Sulfate Doping Promotes Agglomeration of Calcium Fluoride Crystals.

Calcium salt precipitation is an effective solution to wastewater fluoride pollution. The purity and precipitation efficiency of calcium fluoride is critical for its removal and recovery. This study aimed to reveal the role of coexisting sulfates in the precipitation of calcium fluoride. A low sulfate concentration promoted calcium fluoride precipitation. The size of calcium fluoride-aggregated particle clusters increased from 750 to 2000 nm when the molar ratio of sulfate to fluoride was increased from 0 to 3:100. Sulfate doped in the calcium fluoride crystals neutralized the positive charge of the calcium fluoride. Online atomic force microscopy measurements showed that sulfate reduced the repulsive force between calcium fluoride crystals and increased the adhesion force from 1.62 to 2.46 nN, promoting the agglomeration of calcium fluoride crystals. Sulfate improved the precipitation efficiency of calcium fluoride by promoting agglomeration; however, the purity of calcium fluoride was reduced by doping. Sulfate reduced the induction time of calcium fluoride crystallization and improved the nucleation rate of calcium fluoride. Sulfate should be retained to improve the precipitation of calcium fluoride and to avoid its loss from the effluents. However, it is necessary to separate sulfate from fluoride to obtain high-purity calcium fluoride. Therefore, sulfate concentration regulation in high-fluoride wastewater is key to achieving the efficient removal and recovery of fluoride ions.

Limy bile syndrome or milk of calcium bile: An unexpected encounter

IntroductionLimy bile or milk of calcium bile caused due to precipitation of calcium salts in bile is an extremely rare condition of gall bladder, wherein the lumen of gall bladder is filled with chalky white paste like material. Not many cases have been reported till date.AimIn this exceptional case, we tried to correlate the radiological and surgical findings with the histopathology.Case studyWe hereby present an interesting case of a 59-year-old male who presented with dyspepsia and painful abdomen and was finally diagnosed with limy bile syndrome.Results and discussionThe etiology of this rare entity is not fully understood, but it certainly has strong association with impacted stone at the neck of gall bladder and hyperparathyroidism. Females are more commonly affected than males. Patients usually present with complaints of painful abdomen and are commonly diagnosed radiologically, as a radiopacity in gall bladder. Cholecystectomy is the preferred method of treatment for this unusual condition and histopathologically chronic cholecystitis is seen along with presence of slender needle shaped crystals of calcium salts.ConclusionsA thorough evaluation of the clinicoradiological and histopathological findings can sometimes bring to light many uncommon variants of common looking pathologies.

Preparation of vanadyl sulfate electrolyte for vanadium flow battery from vanadium slag using calcium salt precipitation, sodium carbonate leaching and solvent extraction

The conventional process of recovering vanadium from vanadium slag produces residue and wastewater containing toxic V(V) and Cr(VI), which pollute the environment. To address this problem, herein, low valence vanadium (LVV) solution is produced from vanadium slag under controlled oxidation, additionally, V(IV), Fe(II), Cr(III), and Mn(II) are separated from the LVV solution through sodium diethyldithiocarbamate complexation (DDTC), based on previous studies. Subsequently, V(IV) is recovered as calcium salt of V(IV) (CaV2O5), which is subjected to sodium carbonate leaching and solvent extraction with Aliquat 336 in the form of tetramine to produce a high-purity VOSO4 solution. This solution serves as an electrolyte for the vanadium redox flow battery. During leaching, CaV2O5 is converted to CaCO3 as vanadium is recovered in solution up to 99.2%, wherein 88.2% vanadium is in the form of V(IV), thus indicating that vanadium is slightly oxidized after leaching for 60 min. Analysis of the leaching mechanism reveals that V(IV) is in the form of V4O92− and HV2O5− in the pregnant leach solution (PLS), and V(V) is in the forms of VO43−. After acidification with H2SO4, Aliquat 336 extracts V(IV) and V(V) via an anion-exchange mechanism, without adjusting the pH of the leach solution. Further, equations for the extraction and stripping reactions are deduced. The total vanadium extraction and stripping efficiencies exceed 99.3% and 97.2%, respectively. Finally, high-purity VOSO4 electrolyte is obtained after using activated carbon to remove organic, and the corresponding V(IV) ion concentration reaches 77.8 g/L. The cyclic voltammetry test results reveal identical electrochemical properties between the electrolyte product and commercial high-purity VOSO4. Therefore, this process of preparing high-purity VOSO4 electrolyte from vanadium slag without producing V(V) and Cr(VI) provides an effective method for comprehensively utilizing vanadium slag.

Pathomechanism of the IVDs Degeneration and the Role of Neurotrophic Factors and Concentration of Selected Elements in Genesis of Low Back Pain.

Degenerative disc disease of the lumbosacral spine is a very common medical problem. An episode of sciatica occurs at least once in the life of 60-90% of the human population. A phenomenon that is closely related to the process of lowering the pH of the extracellular matrix degenerating the intervertebral disc (IVD) is the precipitation of calcium salts, especially pyrophosphate dehydrate and hydroxyapatite. In such an altered environment of the IVD, we can observe an increased influx of monocytes, macrophages, T-lymphocytes, as well as non-immunocompetent cells, which are a source of cytokines, e.g., tumor necrosis alpha (TNF-α), interleukin- (IL-1β, IL-8). The above-mentioned mediators of an inflammatory condition contribute to an increase in the expression of Brain-Derived Neurotrophic Factor (BDNF) and Glial cell Derived Neurotrophic Factor (GDNF) in mast cells and chondrocytes, as well as to the descending transport of these mediators along the nerve endings. In the process of degeneration of the IVD as a result of repeated and even slight injuries, there is damage to the connections of the endplate of the vertebral bodies with the IVD, which results in an impairment of the penetration of nutritional substances and water into the disc. As a consequence, there is an overexpression of the brain-derived neurotrophic factor GDNF, as well as neuromodulin (GAP-43) in the mast cells and chondrocytes of the IVDs, while descending transport of these mediators along the nerve fibers is also observed.

In Vivo Assessment of the Calcium Salt-Forming Ability of a New Calcium Silicate-Based Intracanal Medicament: Bio-C Temp

Calcium salt precipitation induced by intracanal medicaments contributes to the formation of apical hard tissue during apexification. This study compared the calcium salt-forming ability of a new calcium silicate-based intracanal medicament (Bio-C Temp) with that of two commercial calcium hydroxide pastes (Calcipex Plane II and Vitapex) in a rat subcutaneous implantation model. Polytetrafluoroethylene tubes containing each of the three materials were subcutaneously implanted in 4-week-old male Wistar rats. After 28 days, the composition and amount of calcium salts formed at the material-tissue interface were assessed using micro-Raman spectroscopy, X-ray diffraction, and elemental mapping. The tested materials produced white precipitates that had Raman spectra with peaks corresponding to hydroxyapatite and calcite. X-ray diffraction detected hydroxyapatite formation on Calcipex Plane II and Vitapex implants, as well as calcite formation on all three materials. Elemental mapping revealed that Bio-C Temp generated significantly smaller calcium- and phosphorus-rich calcified regions within the subcutaneous connective tissue than Vitapex. These results indicate that Bio-C Temp produced less calcium salt in rat subcutaneous tissue than Vitapex, although all materials formed hydroxyapatite and calcite in rat subcutaneous tissue. Bio-C Temp could be less effective than Vitapex in promoting apical hard tissue formation during apexification.

Risk Evaluation of Chemical Clogging of Irrigation Emitters via Geostatistics and Multivariate Analysis in the Northern Region of Minas Gerais, Brazil

In this study, we analyzed the hydrogeochemistry of 350 underground wells in the northern region of the state of Minas Gerais, Brazil, for water-chemical parameters that may contribute to the chemical clogging of emitters in drip irrigation systems. Risk class maps were generated for each parameter, and the area was classified based on the water characteristics, considering the degree of water-use restriction in micro-irrigation (i.e., no, moderate, and severe restriction). Inverse distance-weighted, random forest, and ordinary kriging methods were used as interpolation methods. Moreover, a multivariate analysis was conducted to analyze the results. Pearson’s correlation coefficient showed a strong and significant correlation between pH and carbonates, hardness, total dissolved solids (TDS), and electrical conductivity (EC) and between TDS and EC. Principal component analysis revealed that most of the variations in the water quality of the wells could be explained by water–rock interactions with the consequent dissolution of minerals. The principal components were natural sources of ionic salt groups, dissolution of minerals rich in alkaline cations, chemical weathering of iron–magnesium minerals, and increased pH with the conversion of bicarbonates into carbonates. In the parameter cluster analysis, three possible mechanisms that contribute to emitter clogging in the study area were identified: precipitation of calcium and magnesium salts; oxidation of iron and manganese ions forming oxides and insoluble hydroxides; an increase in pH, which converts bicarbonates into carbonates. Clustering analysis revealed the wells that are susceptible to clogging with the exact cause.

Idiopathic Calcinosis Cutis Masquerading as Malignancy - The Mystery of Two Cases Revealed on Cytology

Calcinosis cutis also commonly called as Calciphylaxis is one of the uncommon conditions characterized by precipitation and deposition of phosphate and calcium salts in the dermis and subcutaneous tissues. We report two different cases clinical diagnosed as malignancy and final diagnosis was made on FNAC which correlated with the histopathology. A 45-year-old women came with a compliant of swelling over lateral aspect of thigh on left side since 6 months. Provisional diagnosis of liposarcoma was made clinically and on FNAC given as Calcinosis cutis which correlated with histopathology. A 62-year-old women came with compliant of swelling over lateral aspect of thigh on right side since 10 months associated with pain. Provisional diagnosis of soft tissue sarcoma was made clinically and advised for FNAC clinically and on FNAC given as Calcinosis cutis which correlated with histopathology. Calcinosis cutis is a condition in which there is organized and localized deposition of calcium in the skin. The evolution of the lesions depends on the aetiology of the calcification. The pathogenesis still remains unclear, but several theories have been suggested for this. Calcinosis cutis is a potential mimic of a neoplastic lesion. FNAC is a simple, rapid and reliable technique and which helps in diagnosis of such lesions. Keywords: Mimicker, Fine needle aspiration cytology, Diagnosis

Vascular Smooth Muscle Cell Neutral Sphingomyelinase 2 in the Release of Exosomes and Vascular Calcification.

Vascular calcification (VC) is the pathological precipitation of calcium salts in the walls of blood vessels. It is a risk factor for cardiovascular events and their associated mortality. VC can be observed in a variety of cardiovascular diseases and is most prominent in diseases that are associated with dysregulated mineral homeostasis such as in chronic kidney disease. Local factors and mechanisms underlying VC are still incompletely understood, but it is appreciated that VC is a multifactorial process in which vascular smooth muscle cells (VSMCs) play an important role. VSMCs participate in VC by releasing extracellular vesicles (EVs), the extent, composition, and propensity to calcify of which depend on VSMC phenotype and microenvironment. Currently, no targeted therapy is available to treat VC. In-depth knowledge of molecular players of EV release and the understanding of their mechanisms constitute a vital foundation for the design of pharmacological treatments to combat VC effectively. This review highlights our current knowledge of VSMCs in VC and focuses on the biogenesis of exosomes and the role of the neutral Sphingomyelinase 2 (nSMase2).

Conceptual Evaluation of Factors Controlling Groundwater Chemistry in Ad-Dawadmi, Saudi Arabia, Using Visualization and Multiple Lines of Evidence

Understanding the hydrogeochemical and physicochemical processes and factors controlling the chemical characteristics of groundwater (GW) is essential in water resources studies. In this work, the authors explored, applied, and evaluated the practicality of a series of analysis methods, exploring their ability to improve the representation of the generic GW chemical datasets. The demonstration resulted in a detailed explanation of findings and interpretations, which benefits newcomers who may not be experts in managing such data. Visualization-based, facile, readily readable, and interpretable graphs were tuned and applied to identify the interconnected controlling factors. The examined varieties were bubble diagrams, 3D surface plots, and scatter box plot matrices. Box plot matrices yielded intensive information about the significant interacting parameters in one graph. Employing bubble diagrams produced vast detail, allowing the identification of the significant processes and enabling the recognition of internally acting mechanisms that were otherwise hidden. The identified GW evolution processes include aerosol dissolution, evaporation, direct and reverse ion exchange, precipitation of calcium salts, flushing out of soil-bounded salts, and rock weathering. pH and HCO3− fluctuations coupled with evaporation were recognized as prominent factors giving rise to the vicious salinization cycle, which is thought to be the process causing the worst deterioration in the GW quality and the salinity within the study area.

Behaviour of minerals during the vacuum concentration of dairy ultrafiltration permeates

Whey concentration using evaporators results in deposit of matter on the hot surfaces of the evaporation tubes. The mass deposited during concentration depends mainly on the mineral composition of the whey, which varies considerably depending on the production process. We investigated the behaviour of ultrafiltration permeates (UFP) during concentration and the susceptibility of their mineral fraction to precipitation. UFP with differing mineral compositions were produced by acidification of milk with different acids to pH values between 4.6 and 6.3, followed by ultrafiltration. The results revealed either no precipitation or the precipitation of calcium salts (calcium phosphate, calcium citrate) in the concentrates. The behaviour of mineral fraction during concentration could be assessed by considering: (i) the nature and quantities of cations and anions in the concentrates, (ii) the anionic forms present at the pH of the concentrates and their association constants with calcium, and (iii) the solubility limit of calcium salts.

The molecular mechanism research of cartilage calcification induced by osteoarthritis

ABSTRACT To explore the molecular mechanism of cartilage calcification induced by osteoarthritis (OA) based on distal-less homeobox gene 5 – alkaline phosphatase – integrin-binding sialoprotein – ecto-nucleotide pyrophosphatase 1 (DLX5-ALPL-IBSP-ENPP1) signal axis. Twenty-four rabbits were selected to build models of cartilage calcification induced by OA and randomly divided into 3 groups. The first group was the normal group whose rabbits were injected into 0.9% saline (0.3 mL), and the second group was model group. The third group was model group whose rabbits were injected into DLX5 antibody by caudal vein. Alizarin red calcium staining was used to analyze calcium deposition of cartilage matrix. Immunohistochemical staining was used to analyze the relative expression levels of proteins DLX5 and ENPP1, and western blot was used to analyze the DLX5, ALPL, IBSP, and ENPP1 expression. Calcium salt precipitation was the most serious, and the calcification area increased in the model group. Although calcified nodules appeared in the anti-DLX5 group, they were relatively few. Immunohistochemical staining analysis showed that the protein DLX5 located in the nucleus and the protein ENPP1 located in the extracellular matrix. Western blot analysis showed that the expressions of proteins DLX5, ALPL, IBSP, and ENPP1 were the highest in OA Model group than that of NC group, followed by anti-DLX5 group. The proteins DLX5, ALPL, IBSP, and ENPP1 can promote cartilage calcification induced by OA based on DLX5-ALPL-IBSP-ENPP1 signal axis.

Utilization of dairy beta stream to produce phospholipids products by salt precipitation and solvent fractionation

AbstractDairy phospholipids (PLs) have unique functional and nutraceutical properties over PLs obtained from other sources that typically lack phosphatidylserine (PS) and sphingomyelin (SM). In this study, an underutilized dairy by‐product, beta stream, was used for the production of enriched dairy PLs products and membrane proteins by solvent extractions. After calcium salt precipitation of the membrane components, various green (i.e., safer or bioderived) solvent systems were evaluated for their capabilities for PLs extraction from the PLs‐protein‐salt precipitate in comparison to the standard Folch extraction (chloroform: methanol, 2:1, v/v). Among the five solvent systems (Folch alternatives) evaluated, the combination of hexane and isopropanol (H:IP, 3:2, v/v) was identified as the best for total lipid and PLs extraction, resulting in a recovery of 74.4% and 65.7% (w/w), respectively. EDTA chelating of the calcium ions was applied to produce a salt‐free membrane protein product. A treatment with 0.2% EDTA was able to significantly reduce the calcium content to 0.20 mg/g protein compared to 58.81 mg/g in the initial calcium‐precipitated MFGM. EDTA chelating of cations also facilitated the extraction of lipids during H:IP (3:2) treatment, which increased the total recovery of total lipid and PLs to 90.7% and 82.5% (w/w), respectively. Overall, this study demonstrates a great potential for the utilization of beta stream and other low‐solids content aqueous dairy by‐products for PLs recovery and further fractionation. Value‐added dairy products (PLs and membrane proteins) can be obtained using green solvents identified in this study, and the process is industrially scalable.

Enzyme‐Induced Ferrification of Hydrogels for Toughening of Functional Inorganic Compounds

AbstractEnzyme‐induced mineralization (EIM) has been shown to greatly enhance the mechanical properties of hydrogels by precipitation of calcium salts. Another feature of such hydrogels is their high toughness even when containing finely nanostructured mineral content of ≈75 wt%. This might be useful for bendable materials with high content of functional inorganic nanostructures. The present study demonstrates that EIM can form homogeneous nanostructures of water‐insoluble iron salts within hydrogels. Crystalline iron(II) carbonate precipitates urease‐induced within polyacrylate‐based hydrogels and forms platelet structures that have the potential of forming self‐organized nacre‐like architectures. The platelet structure can be influenced by chemical composition of the hydrogel. Further, amorphous iron(II) phosphate precipitates within hydrogels with alkaline phosphatase, forming a nanostructured porous inorganic phase, homogeneously distributed within the double network hydrogel. The high amount of iron phosphate (more than 80 wt%) affords a stiffness of ≈100 MPa. The composite is still bendable with considerable toughness of 400 J m−2 and strength of 1 MPa. The high water content (>50%) may allow fast diffusion processes within the material. This makes the iron phosphate‐based composite an interesting candidate for flexible electrodes and demonstrates that EIM can be used to deliberately soften ceramic materials, rendering them bendable.

Mechanical properties and in vitro biodegradation behavior of GASAR porous Mg-Ag alloy

In this thesis, porous pure Mg and Mg-3 wt%Ag alloys with oriented regular pore structures were prepared by the metal/gas eutectic unidirectional solidification method (GASAR process). The effects of the Ag content on the mechanical properties and early in vitro biodegradation behavior of porous Mg-Ag alloys were investigated. The results of compression experiments showed that Ag addition significantly enhanced the compressive strength and elastic modulus of the porous Mg-Ag alloy. Immersion experiments in SBF at 37℃ showed that although the Mg-3 wt%Ag alloy exhibited a faster corrosion reaction, the addition of Ag facilitated the precipitation of calcium and phosphorus salts, resulting in better osteoinductivity of the samples, which indicates its feasibility as a potential tissue engineering scaffold.

Silk Protein Composite Bioinks and Their 3D Scaffolds and In Vitro Characterization.

This paper describes the use of silk protein, including fibroin and sericin, from an alkaline solution of Ca(OH)2 for the clean degumming of silk, which is neutralized by sulfuric acid to create calcium salt precipitation. The whole sericin (WS) can not only be recycled, but completely degummed silk fibroin (SF) is also obtained in this process. The inner layers of sericin (ILS) were also prepared from the degummed silk in boiling water by 120 °C water treatment. When the three silk proteins (SPs) were individually grafted with glycidyl methacrylate (GMA), three grafted silk proteins (G-SF, G-WS, G-ILS) were obtained. After adding I2959 (a photoinitiator), the SP bioinks were prepared with phosphate buffer (PBS) and subsequently bioprinted into various SP scaffolds with a 3D network structure. The compressive strength of the SF/ILS (20%) scaffold added to G-ILS was 45% higher than that of the SF scaffold alone. The thermal decomposition temperatures of the SF/WS (10%) and SF/ILS (20%) scaffolds, mainly composed of a β-sheet structures, were 3 °C and 2 °C higher than that of the SF scaffold alone, respectively. The swelling properties and resistance to protease hydrolysis of the SP scaffolds containing sericin were improved. The bovine insulin release rates reached 61% and 56% after 5 days. The L929 cells adhered, stretched, and proliferated well on the SP composite scaffold. Thus, the SP bioinks obtained could be used to print different types of SP composite scaffolds adapted to a variety of applications, including cells, drugs, tissues, etc. The techniques described here provide potential new applications for the recycling and utilization of sericin, which is a waste product of silk processing.

Mechanisms Underlying Calcium Nephrolithiasis.

Nephrolithiasis is a worldwide problem with increasing prevalence, enormous costs, and significant morbidity. Calcium-containing kidney stones are by far the most common kidney stones encountered in clinical practice, and thus, hypercalciuria is the greatest risk factor for kidney stone formation. Hypercalciuria can result from enhanced intestinal absorption, increased bone resorption, or altered renal tubular transport. Kidney stone formation is complex and driven by high concentrations of calcium-oxalate or calcium-phosphate in the urine. After discussing the mechanism mediating renal calcium salt precipitation, we review recent discoveries in renal tubular calcium transport from the proximal tubule, thick ascending limb, and distal convolution. Furthermore, we address how calcium is absorbed from the intestine and mobilized from bone. The effect of acidosis on bone calcium resorption and urinary calcium excretion is also considered. Although recent discoveries provide insight into these processes, much remains to be understood in order to provide improved therapies for hypercalciuria and prevent kidney stone formation.

Chloride removal from municipal solid waste incineration fly ash using lactic acid fermentation broth.

As far as improvement of chlorine removal from fly ash by lactic acid fermentation broth (LAFB) was concerned, it is particularly important to explore the instinct mechanism and understand how leaching protocols (i.e. lactic acid addition amount and timing) affect the dechlorination efficiency. Results revealed that the WLL leaching protocol yielded the highest dechlorination efficiency (i.e. removed 98.7% of the total chlorine content of fly ash). The undissolved chlorine in fly ash residue might wrap inside the crystal structure of CaAlSiO4(OH). Given that the chlorine removal from fly ash might prohibit by the newly formed calcium salt precipitation, exclusively increase the addition amount of LAFB (i.e. LLL protocol) did not necessarily stimulate the dechlorination efficiency. Conversely, it might accelerate the fly ash mass reduction (compared with WLL protocol), resulting in a high chlorine content in fly ash residue. Therefore, instead of increasing lactic acid strength, reducing the thickness of the calcium salt precipitation layer or breaking the crystal structure of CaAlSiO4(OH) during the leaching process was suggested for efficient fly ash dechlorination.

Increasing inhibition performance of simultaneous precipitation of calcium and strontium sulfate scales using a new inhibitor — Laboratory and field application

In this work, the calcium sulfate (anhydrite) and strontium sulfate precipitation simultaneous prediction was performed at various reservoir pressures, temperatures, and mixing ratios of injection and formation water. In addition, in order to prevent the precipitation of calcium and strontium sulfate scale, the inhibition performance of five various well-known scale inhibitors was evaluated by conducting different experiments. The results showed that the possibility of calcium and strontium sulfate precipitation was directly proportional to the temperature and inversely proportional to pressure. The worst scenario for the simultaneous calcium and strontium sulfate scale formation was observed in a mixing ratio of 1:1 injection and formation water. A mixture of reagents (new inhibitors) — DPAAI (three phosphonate scale inhibitors, ammonium bifluoride, isopropyl alcohol, and water) was developed in order to enhance the prevention performance of calcium and strontium sulfate salt precipitation. DPAAI had an efficiency of 94% under static conditions, and its effectiveness was not changed by increasing the temperature up to 150 °C. The induction period of strontium sulfate crystallization in the presence of DPAAI was 70 min, which was 2.89 times longer than in a blank case. The interfacial tension of DPAAI and oil was reduced more than 10 times in the presence of an alcohol propoxy sulfate at a mass concentration of 1.5%. Furthermore, the rock permeability with the use of DPAAI was improved from 33% to 95% of the initial permeability. The squeeze lifetime of DPAAI for preventing the simultaneous calcium and strontium sulfate scale precipitation was about 85% longer than the squeeze lifetime of the investigated common phosphonate scale inhibitors.

Exploring key ionic interactions for magnesium degradation in simulated body fluid – A data-driven approach

We have studied the degradation of pure magnesium wire in simulated body fluid and its subsets under physiological conditions to enable the prediction of the degradation rate based on the medium's ionic composition. To this end, micro-computed tomography and scanning electron microscopy with energy-dispersive X-ray spectroscopy were used, followed by a tree regression analysis. A non-linear relationship was found between degradation rate and the precipitation of calcium salts. The mean absolute error for predicting the degradation rate was 1.35 mm/yr. This comparatively high value indicates that ionic interactions were exceedingly complex or that an unknown parameter determining the degradation may exist.

S1427 Lime-A-Way: Limy Bile Syndrome Complicated by Biliary Obstruction

INTRODUCTION: Limy bile syndrome (LBS), also known as milk of calcium bile, is a rare disorder of unclear etiology, characterized by the accumulation of thick, paste-like radiopaque calcium salts in the gallbladder and common bile duct (CBD). It is prevalent in 0.1% of patients that undergo cholecystectomies and can lead to life-threatening complications, necessitating early recognition. We report a case of this rare clinical entity presenting with obstructive jaundice and causing debilitating abdominal pain and chronic cholecystitis. CASE DESCRIPTION/METHODS: A 51-year-old man with no past medical history presented with 4 months of worsening sharp, post-prandial right upper quadrant abdominal pain and nausea. Vital signs were normal. Physical exam was notable for scleral icterus, jaundice, tenderness to palpation in the right upper quadrant of his abdomen and negative Murphy’s sign. Laboratory data was notable for AST 195 U/L, ALT 520 U/L, alkaline phosphatase 186 U/L, total bilirubin 6.2 mg/dL (conjugated 2.8/unconjugated 0.9). Abdominal ultrasound showed CBD dilation to 10 mm without gallstones. Abdominal CT showed a dilated CBD and densely hyperattenuating material along the inferior gallbladder wall and within the CBD (Figure 1). Given the absence of stones, the diagnosis of LBS was suspected. He underwent ERCP with sphincterotomy and copious amounts of thick paste-like sludge was swept from the duct, confirming the diagnosis of LBS (Figures 2, 3). His symptoms and biochemical abnormalities resolved rapidly following ERCP, and he underwent laparoscopic cholecystectomy with pathology confirming chronic cholecystitis. DISCUSSION: LBS is a rare disorder with poorly defined pathogenesis. Abnormalities in calcium metabolism, variable gallbladder pH and gallbladder stasis are factors that may cause calcium salt precipitation. Most patients present with biliary colic or cholecystitis. LBS can also present as incidental radiopaque shadows below the liver on abdominal x-rays in asymptomatic individuals. The identification of these calcifications should prompt further investigation with ultrasound and CT to distinguish LBS from other calcifying pathologies such as porcelain gallbladder in which gallbladder wall calcification is demonstrated as opposed to radiopaque material within the gallbladder itself. Timely recognition of this rare syndrome and early cholecystectomy is crucial as it can lead to complications such as biliary obstruction, cholangitis, biliary pancreatitis and cholecystitis.Figure 1.: CT showing hyperattenuating material along the inferior gallbladder wall.Figure 2.: EGD showing thick paste-like sludge.Figure 3.: ERCP images.