Gastric lanthanosis (lanthanum deposition) in dialysis patients treated with lanthanum carbonate

Lanthanum Gastropathy in Gastrectomy Specimen: A Case Report

Lanthanum carbonate (LC) is a phosphate binder used in end-stage renal disease (ESRD) with few adverse effects due to poor systemic absorption. Gastrointestinal deposition is likely due to alterations in epithelial permeability from inflammation in ESRD. It is challenging to detect in cases with minimal deposition and may be missed on endoscopy and biopsy. A 36-year-old with ESRD who was evaluated for gastrectomy was found to have LC deposition histologically. Years later, the excised portion had similar findings. This case allows for evaluation of LC gastropathy in a resection specimen, providing the opportunity to showcase its unique pathology features.

Novel case of laparoscopically resected gastric adenocarcinoma concurrent with lanthanum deposition

A 73-year-old man taking lanthanum carbonate for hemodialysis showed progressing gastric mucosal changes with lanthanum deposition. Regular examination revealed concurrent gastric carcinoma. The extent and depth of its invasion were ambiguous because of the surrounding lanthanum deposition. Furthermore, there could be other potent carcinomas, and curative laparoscopic gastrectomy was performed.

Evaluation of cerium oxide as a phosphate binder using 5/6 nephrectomy model rat

BACKGROUND

The number of chronic kidney disease (CKD) patients continues to increase worldwide. CKD patients need to take phosphate binders to manage serum phosphorus concentrations. Currently, several types of phosphate binder, including lanthanum carbonate, are used. However, they each have disadvantages.

METHODS

In this study, we evaluated cerium oxide as a new phosphate binder in vitro and in vivo. First, cerium oxide was mixed with phosphoric acid at pH 2.5 or 7.0, and residual phosphoric acid was measured by absorption photometry using colorimetric reagent. Second, cerium oxide was fed to 5/6 nephrectomy model rats (5/6Nx), a well-known renal damage model. All rats were measured food intake, water intake, feces volume, and urine volume, and collected serum and urine were analyzed for biochemical markers.

RESULTS

Cerium oxide can adsorb phosphate at acidic and neutral pH, while lanthanum carbonate, which is a one of popular phosphate binder, does not dissolve at neutral pH. Cerium oxide-treatment reduced serum phosphate concentrations of 5/6Nx rats without an increase in serum alanine transaminase levels that would indicate hepatotoxicity, and cerium oxide-treatment maintained serum creatinine and blood urea nitrogen levels, while those of normal 5/6Nx rats increased slightly.

CONCLUSIONS

These results suggest that cerium oxide can be a potential phosphate binder. Decreased body weight gain and increased water intake and urine volume in 5/6Nx rats were thought to be an effect of nephrectomy because these changes did not occur in sham operation rats. Additional investigations are needed to evaluate the longer-term safety and possible accumulation of cerium oxide in the body.

Lanthanum Carbonate Opacities—A Systematic Review

Background: Lanthanum carbonate is a phosphate binder used in advanced kidney disease. Its radiopaque appearance has been described in many case studies and case series. Misinterpretation of this phenomenon leads to unnecessary diagnostic tests and procedures. The objectives of this study were to summarize the literature on lanthanum carbonate opacities and present a visual overview. Methods: A systematic search was conducted using MEDLINE, Embase, and Web of Science. We included all types of studies, including case reports/studies, describing radiological findings of lanthanum carbonate opacities in patients with chronic kidney disease. No filter for time was set. Results: A total of 36 articles were eligible for data extraction, and 33 articles were included in the narrative synthesis. Lanthanum carbonate opacities were most commonly reported in the intestines (26 studies, 73%), stomach (8 studies, 21%), and the aerodigestive tract (2 studies, 6%). The opacities in the intestine were most frequently described as multiple, scattered radiopaque densities, compared with the aerodigestive tract, where the opacities were described as a single, round foreign body. Suspicion of contrast medium or foreign bodies was the most common differential diagnosis. LC opacities in patients with CKD are commonly misinterpreted as foreign bodies or suspect contrast media. Conclusions: CKD patients treated with LC may have opacities throughout the digestive tract that can vary in appearance. Stopping LC treatment or changing to an alternative phosphate binder prior to planned image studies can avoid diagnostic confusion. If this is not an option, knowledge of the presentation of LC opacities is important.

Gastric lanthanosis (lanthanum deposition) in an immunosuppressed patient that discontinued lanthanum carbonate seven years ago

A 72-year-old female patient used the oral phosphate binder lanthanum carbonate for 6 years, before discontinuing it after receiving a pancreas and kidney transplant. Now, 7 years after discontinuation, the patient developed bilious emesis. An upper gastrointestinal endoscopy showed an unspecific gastritis. Biopsies showed subepithelial crystalline deposits consistent with gastric lanthanosis.

[Unexpected deposits in the upper gastrointestinal tract : When medical history matters]

In order to regulate their phosphate uptake, patients with end-stage renal disease rely on phosphate binders such as lanthanum carbonate (LC). The earliest histopathological reports of this rare entity in the gastrointestinal mucosa were described and published in 2015.We present a case of an 80-year-old patient with LC gastro-enteropathy. Histopathologically it can mimic other drug-induced depositions and even infectious or neoplastic entities. Evaluation of the patient's medical and especially drug history is essential to obtain the appropriate diagnosis. We present an overview of the clinical presentation and histological differential diagnosis of LC.

Investigation of the clinical significance and pathological features of lanthanum deposition in the gastric mucosa

Background

There are often specific endoscopic findings caused by deposition of lanthanum (La) in the gastric mucosa of patients taking lanthanum carbonate (LaC), a novel phosphate binder for patients on hemodialysis. We conducted a retrospective study to investigate the clinical significance of La deposition in the gastric mucosa, and the association between endoscopic features and histologic findings in the same population.

Methods

We compared background factors in patients taking LaC with and without La deposition in their gastroscopic biopsy specimen. We also investigated the relationship between gastric endoscopic biopsy specimens with La deposition and the concurrent endoscopic images.

Results

There was a significant difference in the total dose of LaC between the La-positive and La-negative groups (990 g [180–3150 g] vs. 480 g [225–1328 g]; p = 0.013). In 27 biopsy specimens with specific whitish mucosa, 10 showed mild histiocytic infiltration and 17 showed severe infiltration. In contrast, among 24 specimens with non-whitish mucosa, 5 showed no histiocytic infiltration, 10 showed mild infiltration, and 9 showed severe infiltration. There was a significant relationship between endoscopic features and the degree of histiocytic infiltration (p = 0.026).

Conclusions

We demonstrated that La deposition in the gastric mucosa depended on the total dose of LaC and was not affected by background factors. The specific endoscopic features of La deposition are associated with the infiltration of histiocytes, which represents the body’s normal response to foreign bodies.

Trial registry The protocol was registered in the University Hospital Medical Information Network Clinical Trial Registry (UMIN000038929, https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000044393).

Clinical Evaluation of the Safety, Efficacy and Tolerability of Lanthanum Carbonate in the Management of Hyperphosphatemia in Patients with End-Stage Renal Disease

Patients with progressive chronic kidney disease (CKD) commonly develop mineral and bone abnormalities and extraskeletal calcifications with following increased cardiovascular risk. A key pathophysiological role is played by hyperphosphatemia. Since diet and dialysis are often insufficient to control serum phosphorus levels, many patients require treatment with phosphate binders. Among them is lanthanum carbonate, an aluminum-free non-calcium-based compound. The present review summarizes the most recent literature data concerning the safety, efficacy and tolerability of lanthanum carbonate in patients with end-stage renal disease and hyperphosphatemia. The drug is taken orally as chewable tablets or powder with only minimal gastrointestinal absorption and resulting reduced risk of tissue deposition and systemic drug interactions. The dissociation of the drug in the acid environment of the upper gastrointestinal tract induces the release of lanthanum ions, which bind to dietary phosphate forming insoluble complexes then excreted in the feces. Even though there is no clear evidence that lowering serum phosphorus levels can improve patient-centered outcomes, a mortality benefit with all phosphate binders, especially non-calcium containing ones, is not excluded. Lanthanum carbonate has been suggested to decrease all-cause mortality but not cardiovascular event rate compared to other phosphate binders. It induces a lower suppression of bone turnover than calcium carbonate and calcium acetate and may improve systolic function and cardiac dimension compared to calcium carbonate. Moreover, the use of lanthanum carbonate has been associated with better nutritional status compared to other phosphate binders, lower risk for hypercalcemia than calcium-containing binders, and amelioration of mild metabolic acidosis contrary to sevelamer hydrochloride. Main adverse effects include nausea, alkaline gastric reflux, gastric deposition of lanthanum, gastrointestinal obstruction, subileus, ileus, perforation, fecal impaction, and reduction of gastrointestinal absorption of some drugs including statins, angiotensin-converting enzyme inhibitors and some antibiotics such as fluoroquinolones or tetracyclines.

Quantitative Visualization of Lanthanum Accumulation in Lanthanum Carbonate-Administered Human Stomach Tissues Using Mass Spectrometry Imaging

Platinum, a transition metal that is widely used in anti-cancer agents, also results in the development of nephropathy due to severe adverse reactions caused by platinum-induced nephrotoxicity. Reports on imaging with metals other than platinum remain are limited, even in preclinical studies. Furthermore, most of these are case reports, and the relationship between the distribution of the metal and clinical observations in human samples is not well understood. Here we report on visualizing lanthanum (¹³⁹La), a component of Fosrenol, which is usually used for the treatment of hyperphosphatemia. Gastric inflammation, also known as hemorrhagic gastritis, is the main adverse event caused by Fosrenol. To conduct this study, ¹³⁹La was visualized in gastric biopsy samples obtained from a patient using quantitative laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). We also compared the distribution of ¹³⁹La in tissue and histochemical results. The areas where ¹³⁹La accumulated corresponded to the macrophage-positive areas observed in immunohistochemistry studies using an anti-CD68 antibody. In contrast, we observed a debris-like crystal morphology in hematoxylin and eosin staining tissues. The debris was also associated with ¹³⁹La accumulation. The abnormal accumulation of ¹³⁹La crystals caused the observed inflammation. This phenomenon was previously characterized, but this is the first report in which ¹³⁹La distribution and histochemical results are compared using LA-ICP-MS.

Lanthanum Deposition in the Gastroduodenal Mucosa of Dialysis Patients

Lanthanum (La) carbonate (LC) is one of the most popular phosphate binders used in dialysis patients with end-stage renal disease. Only a small amount of LC is believed to be absorbed from the gastrointestinal (GI) tract because LC strongly binds to dietary phosphate and forms insoluble complexes. La deposition in the gastroduodenal mucosa has been recently identified. Endoscopically, La deposition is demonstrated as whitish lesions of varying sizes and shapes in the gastroduodenal mucosa. Microscopically, La deposition is characterized by histiocytic reaction or small foreign body granulomas containing gray or brown materials mainly in the lamina propria of the GI mucosa. Some histiocytes containing La can migrate into regional lymph nodes via the lymphatic flow. The amount of La deposition in the gastroduodenal mucosa is correlated with the total dose of LC administration, and La deposition is almost consistently observed in LC-treated dialysis patients. Although the detailed mechanism of La deposition in the GI tract is still unclear, several factors, such as gastric pH and metaplastic change of the mucosal epithelium, may be involved in the La deposition in the gastroduodenal mucosa. Here we present an overview of the feature of La deposition in the GI tract.

Utility of Scanning Electron Microscopy Elemental Analysis Using the 'NanoSuit' Correlative Light and Electron Microscopy Method in the Diagnosis of Lanthanum Phosphate Deposition in the Esophagogastroduodenal Mucosa

BACKGROUND

We have recently developed the correlative light and electron microscopy of hematoxylin and eosin (H&E)-stained glass slides using the 'NanoSuit' method. The aim of this study is to explore the utility of the new NanoSuit-correlative light and electron microscopy method combined with scanning electron microscopy-energy dispersive X-ray spectroscopy elemental analysis for the diagnosis of lanthanum phosphate deposition in the H&E-stained glass slides.

METHODS

Nine H&E-stained glass slides of the upper gastrointestinal tract mucosa containing the brown pigmented areas by light microscopic observation, which were suspected as lanthanum phosphate deposition, were observed and analyzed by scanning electron microscopy-energy dispersive X-ray spectroscopy using the NanoSuit-correlative light and electron microscopy method.

RESULTS

In all nine slides, the new NanoSuit-correlative light and electron microscopy method combined with scanning electron microscopy-energy dispersive X-ray spectroscopy revealed the accumulation of both lanthanum and phosphorus in the tissue area corresponding to the brown pigment deposition. In addition to the existence of lanthanum phosphate in the stomach and duodenum, known target organs, we observed deposition in the esophagus for the first time. Furthermore, we observed lanthanum phosphate deposition in the background mucosa of stomach containing primary adenocarcinoma.

CONCLUSIONS

Scanning electron microscopy-energy dispersive X-ray spectroscopy analysis using the NanoSuit-correlative light and electron microscopy method is useful for the diagnosis of lanthanum phosphate deposition in the H&E-stained glass slides. Lanthanum phosphate deposition occurs not only in the stomach and duodenum but also in the esophagus.

Distribution of lanthanum carbonate in the gastric mucosa confirmed by electron microscopy with a magnified endoscopy: a case report and literature review

We describe the case of a 70-year-old man with diabetic nephropathy undergoing hemodialysis. Four years following hemodialysis, he started taking lanthanum carbonate 1500 mg/day and lansoprazole 30 mg/day. Nine years following hemodialysis, he underwent screening esophagogastroduodenoscopy, which demonstrated the presence of the whitish cobblestone-like mucosa in the gastric corpus and multiple reddish depressed lesions with annular whitish mucosa in the antrum. With magnified narrow-band imaging endoscopy, a yellowish–white substance was observed in the villous structure, and subepithelial vessels were observed on the yellowish–white substance. Biopsies were taken from the whitish cobblestone-like mucosa of the upper corpus, a reddish depressed part of the antrum. Histologically, aggregates of cells containing amphophilic fine granular material were found in the mucosal interstitium. These cells stained positive for CD68 and were identified as histiocytes. Since he had been taking lanthanum carbonate for 5 years, we considered the possibility of histiocyte-mediated phagocytosis of lanthanum. Digital mapping via scanning electron microscopy with energy-dispersive X-ray spectrometry showed the presence of lanthanum and phosphorus in the interstitium and cytoplasm of histiocytes. The white, rough mucosa in the gastric body appeared 6 months following the commencement of lanthanum administration and still exists 3 years and 5 months after discontinuation of lanthanum.

Frequent Involvement of the Duodenum with Lanthanum Deposition: A Retrospective Observational Study

Objective This study aimed to investigate the endoscopic features of lanthanum-associated duodenal lesions and the prevalence of duodenal involvement among patients with pathologically proven lanthanum deposition in the gastrointestinal tract. Methods We retrospectively reviewed 24 patients with pathologically proven lanthanum deposition in the gastrointestinal tract. Patients were subdivided into three groups: Group A, patients with pathologically-proven lanthanum deposition in the duodenum; Group B, patients without lanthanum deposition in the duodenum; and Group C, patients without a biopsy of the duodenum. Results A biopsy examination of the duodenum was performed in 19 patients, and lanthanum deposition was detected in 17 patients (17/19, 89.5%). In group A (n=17), whitish duodenal villi were detected in 15 patients during esophagogastroduodenoscopy (15/17, 88.2%). While the other two patients showed no whitish villi, a biopsy of the duodenal mucosa revealed lanthanum deposition. The deposition of a white substance showing a clear margin was visible within multiple villi under magnified observation in some patients of group A. Group B patients (n=2) also showed whitish villi. However, the whitish color was faint in one case and sparse in the other case. Conclusion Lanthanum deposits in the duodenum may resemble white villi. However, in some cases, these deposits may be unrecognizable during esophagogastroduodenoscopy due to the subtle degree of deposition. Endoscopists should biopsy the duodenum as well as the stomach, regardless of the presence or absence of white villi, for an accurate determination of lanthanum deposition in the gastrointestinal tract.

Case of early-stage gastric cancer identified in the gastric mucosa with lanthanum phosphate deposition

Background and study aims  A 78-year-old man with Helicobacter pylori infection had been undergoing hemodialysis for chronic renal failure and receiving lanthanum carbonate preparations for 3 years. Endoscopy revealed fine white granular discoloration throughout the stomach, a moderately reddish depression on the lesser curvature of the gastric angle, and white granular discoloration in the surrounding area. A magnified image using narrow-band imaging showed that the depressed part had irregular vascular and pit structures. We established a diagnosis of intramucosal gastric cancer and performed endoscopic submucosal dissection. Histopathological examination revealed a well-differentiated adenocarcinoma that was confined to the mucosa of the depressed area. Moreover, using an electron probe microanalyzer-equipped electron microscope, we found that the degree of lanthanum deposition was lower in the tumor region than in the non-tumor region. Thus, the current case can help in understanding the relationship between lanthanum deposition and early-stage gastric cancer. Because gastric cancers can occur in lanthanum deposit-containing mucosa, esophagogastroduodenoscopy should be used carefully after understanding the characteristics of early- stage gastric cancer in such cases.

Review of Drug-induced Injury in Mucosal Biopsies From the Tubular Gastrointestinal Tract

The use of prescription and over-the-counter medications is on the rise in the US population, especially among those aged 65 and over, with over 46% of the population taking at least 1 prescription medication. Given the frequency of medication use, and that the majority of these medications are taken orally, it has become increasingly relevant for pathologist examining endoscopically obtained gastrointestinal tract mucosal biopsies to consider and recognize patterns of mucosal injury associated with various drugs. Reports on injuries associated with certain classes of drugs can be scattered among different sources, making a comprehensive view of various injury patterns and the drugs known to cause them difficult to obtain. Herein, we provide a comprehensive overview of the drugs known to cause mucosal injuries in the tubular gastrointestinal tract organized by the organ involved and the prominent pattern of injury.

A meta-analysis of phosphate binders lanthanum carbonate versus sevelamer hydrochloride in patients with end-stage renal disease undergoing hemodialysis

BACKGROUND AND OBJECTIVES

The purpose of this study was to compare the effects of phosphate binders lanthanum carbonate (LC) versus sevelamer hydrochloride (SH) in end-stage renal disease (ESRD) patients undergoing hemodialysis.

METHODS

Studies including randomized controlled trials (RCTs) comparing phosphate binders lanthanum carbonate versus sevelamer hydrochloride, in ESRD patients undergoing hemodialysis, were identified using a pre-defined search strategy. Phosphate, calcium, calcium-phosphorus product, intact parathyroid hormone, alkaline phosphatase, total cholesterol, and triglyceride were extracted and compared by RevMan 5.1 (The Cochrane Collaboration, Oxford, UK).

RESULTS

Six studies were identified. Meta-analysis showed that SH treatment reduced levels of phosphate, intact parathyroid hormone, and total serum alkaline phosphatase (ALP) when compared with LC treatment. Furthermore, patients on SH treatment tended to have reduced calcium levels, calcium-phosphorus product, total cholesterol, and triglyceride when compared to patients treated with LC, but there was no statistical difference.

CONCLUSION

SH treatment of patients with ESRD is more effective compared to LC treatment. However, more well-designed random control trails are required for confirmation.

Lanthanum-Induced Mucosal Alterations in the Stomach (Lanthanum Gastropathy): a Comparative Study Using an Animal Model

Lanthanum (La) carbonate (LC) is one of the most potent phosphate binders that prevents the elevation of serum phosphate levels in patients with end-stage renal diseases undergoing dialysis. LC binds strongly to dietary phosphate and forms insoluble complexes that pass through the gastrointestinal tract. La deposition in patients treated with LC is a recently documented finding particularly observed in gastric mucosa. We herein describe the detailed gastric mucosal lesions in 45 LC-treated patients and address the potential underlying pathologic mechanism using oral LC administration in rats. Microscopically, La deposition, as shown by subepithelial collections of plump eosinophilic histiocytes or small foreign body granulomas containing coarse granular or amorphous inclusion bodies, was found in the gastric mucosa of 44 (97.8%) of the 45 dialysis patients in the study cohort, which was most frequently associated with foveolar hyperplasia (37.8%). Using oral administration of rats with 1000 mg/day LC for 2 or more weeks, La deposition was consistently detectable in the gastric mucosa but not in other organs examined. In addition, various histologic alterations such as glandular atrophy, stromal fibrosis, proliferation of mucous neck cells, intestinal metaplasia, squamous cell papilloma, erosion, and ulcer were demonstrated in the rat model. Thus, orally administered LC can induce mucosal injury, designated here as La gastropathy, which may alter the local environment and result in La deposition in the gastric mucosa, thereby potentially inducing abnormal cell proliferation or neoplastic lesions.

Pharmacotherapy in chronic kidney disease hyperphosphatemia – effects on vascular calcification and bone health

Hyperphosphatemia (HP) in patients with chronic kidney disease (CKD) leads to complications such as renal osteodistrophy, cardiovascular calcification and hemodynamic abnormalities, all of them having a serious impact on the survival rate and quality of life. Also, HP is a key pathogenic factor in the development of secondary hyperparathyroidism (SHPT) in CKD. Having in regard the significance of controlling serum phosphorus levels (Pi), in this paper, the needs and obstacles to successful pharmacological management of HP in CKD are presented, with an overview of major classes of phosphate binders (PBs) and other drugs affecting Pi level, such as active vitamin D sterols and calcimimetics (CMs). In addition, their effects on progression of cardiovascular calcification and bone health are elaborated. In this regard, a PubMed search was carried out to capture all abstracts and articles relevant to the topic of CKD, HP and mineral metabolism, bone disorders and vascular/valvular calcification (VC), published from January 2007 to August 2017. The search was limited to English language, with the search terms including drug name AND hyperphosphatemia or cardiovascular calcification or bone disorder. Comparative studies, clinical studies/trials and meta-analyses related to different classes/representatives of PBs, vitamin D analogues and CMs were reviewed and research data related to their efficacy and safety compared. Keywords: chronic kidney disease, hyperphosphatemia, phosphate binders, active vitamin D sterols, calcimimetics, bone disorders, cardiovascular calcification