Nephrotic syndrome after treatment with pamidronate

Drug-induced glomerular diseases

Drug-induced kidney diseases represent a wide range of diseases that are responsible for a significant proportion of all acute kidney injuries and chronic kidney diseases. In the present review, we focused on drug-induced glomerular diseases, more precisely podocytopathies - minimal change diseases (MCD), focal segmental glomerulosclerosis (FSGS) - and membranous nephropathies (MN), from a physiological and a pharmacological point of view. The glomerular filtration barrier is composed of podocytes that form foot processes tightly connected and directly in contact with the basal membrane and surrounding capillaries. The common clinical feature of these diseases is represented by the loss of the ability of the filtration barrier to retain large proteins, leading to massive proteinuria and nephrotic syndrome. Drugs such as non-steroidal anti-inflammatory drugs (NSAIDs), D-penicillamine, tiopronin, trace elements, bisphosphonate, and interferons have been historically associated with the occurrence of MCD, FSGS, and MN. In the last ten years, the development of new anti-cancer agents, including tyrosine kinase inhibitors and immune checkpoint inhibitors, and research into their renal adverse effects highlighted these issues and have improved our comprehension of these diseases.

Comprehensive Associations between Acidosis and the Skeleton in Patients with Kidney Disease

SIGNIFICANCE STATEMENT

Renal osteodystrophy (ROD) contributes substantially to morbidity in CKD, including increased fracture risk. Metabolic acidosis (MA) contributes to the development of ROD, but an up-to-date skeletal phenotype in CKD-associated acidosis has not been described. We comprehensively studied associations between acidosis and bone in patients with CKD using advanced methods to image the skeleton and analyze bone-tissue, along with biochemical testing. Cross-sectionally, acidosis was associated with higher markers of bone remodeling and female-specific impairments in cortical and trabecular bone quality. Prospectively, acidosis was associated with cortical expansion and trabecular microarchitectural deterioration. At the bone-tissue level, acidosis was associated with deficits in bone mineral content. Future work investigating acidosis correction on bone quality is warranted.

BACKGROUND

Renal osteodystrophy is a state of impaired bone quality and strength. Metabolic acidosis (MA) is associated with alterations in bone quality including remodeling, microarchitecture, and mineralization. No studies in patients with CKD have provided a comprehensive multimodal skeletal phenotype of MA. We aim to describe the structure and makeup of bone in patients with MA in the setting of CKD using biochemistry, noninvasive imaging, and histomorphometry.

METHODS

The retrospective cross-sectional analyses included 180 patients with CKD. MA was defined as bicarbonate ≤22 mEq/L. We evaluated circulating bone turnover markers and skeletal imaging with dual energy x-ray absorptiometry and high-resolution peripheral computed tomography. A subset of 54 participants had follow-up. We assessed associations between baseline and change in bicarbonate with change in bone outcomes. Histomorphometry, microCT, and quantitative backscatter electron microscopy assessed bone biopsy outcomes in 22 participants.

RESULTS

The mean age was 68±10 years, 54% of participants were male, and 55% were White. At baseline, acidotic subjects had higher markers of bone turnover, lower areal bone mineral density at the radius by dual energy x-ray absorptiometry, and lower cortical and trabecular volumetric bone mineral density and impaired trabecular microarchitecture. Over time, acidosis was associated with opposing cortical and trabecular effects: cortical expansion but trabecular deterioration. Bone-tissue analyses showed reduced tissue mineral density with increased heterogeneity of calcium distribution in acidotic participants.

CONCLUSIONS

MA is associated with multiple impairments in bone quality. Future work should examine whether correction of acidosis improves bone quality and strength in patients with CKD.

Crystal-Induced Podocytopathy Producing Collapsing Focal Segmental Glomerulosclerosis in Monoclonal Gammopathy of Renal Significance: A Case Report

Monoclonal gammopathy–associated crystalline podocytopathy causing collapsing focal segmental glomerulosclerosis (FSGS) is very rare and has been associated with pamidronate therapy. We present the case of a 53-year-old man with vision loss secondary to corneal crystals deposition, nephrotic-range proteinuria, and reduced glomerular filtration rate without associated comorbid conditions. Two kidney biopsies were initially reported as primary FSGS but the patient did not respond to high-dose corticosteroid immunosuppression therapy. Repeat review of biopsies with additional electron microscopy analysis revealed crystalline inclusions in podocytes leading to collapsing FSGS. Subsequent workup revealed an immunoglobulin G κ serum monoclonal protein. Bone marrow biopsy revealed 5% κ-restricted plasma cells with cytoplasmic crystalline inclusions. To our knowledge, this is the first case of monoclonal gammopathy of clinical significance manifesting as crystalline podocytopathy leading to collapsing FSGS and keratopathy leading to vision loss. Crystalline podocytopathy should be considered in the differential diagnosis of collapsing glomerulopathy, and careful ultrastructural examination of the kidney biopsy specimen is crucial to establish this diagnosis.

Bisphosphonates to reduce bone fractures in stage 3B+ chronic kidney disease: a propensity score-matched cohort study

BACKGROUND

Bisphosphonates are contraindicated in patients with stage 4+ chronic kidney disease. However, they are widely used to prevent fragility fractures in stage 3 chronic kidney disease, despite a lack of good-quality data on their effects.

OBJECTIVES

The aims of each work package were as follows. Work package 1: to study the relationship between bisphosphonate use and chronic kidney disease progression. Work package 2: to study the association between using bisphosphonates and fracture risk. Work package 3: to determine the risks of hypocalcaemia, hypophosphataemia, acute kidney injury and upper gastrointestinal events associated with using bisphosphonates. Work package 4: to investigate the association between using bisphosphonates and changes in bone mineral density over time.

DESIGN

This was a new-user cohort study design with propensity score matching.

SETTING AND DATA SOURCES

Data were obtained from UK NHS primary care (Clinical Practice Research Datalink GOLD database) and linked hospital inpatient records (Hospital Episode Statistics) for work packages 1-3 and from the Danish Odense University Hospital Databases for work package 4.

PARTICIPANTS

Patients registered in the data sources who had at least one measurement of estimated glomerular filtration rate of < 45 ml/minute/1.73 m2 were eligible. A second estimated glomerular filtration rate value of < 45 ml/minute/1.73 m2 within 1 year after the first was requested for work packages 1 and 3. Patients with no Hospital Episode Statistics linkage were excluded from work packages 1-3. Patients with < 1 year of run-in data before index estimated glomerular filtration rate and previous users of anti-osteoporosis medications were excluded from work packages 1-4.

INTERVENTIONS/EXPOSURE

Bisphosphonate use, identified from primary care prescriptions (for work packages 1-3) or pharmacy dispensations (for work package 4), was the main exposure.

MAIN OUTCOME MEASURES

Work package 1: chronic kidney disease progression, defined as stage worsening or starting renal replacement. Work package 2: hip fracture. Work package 3: acute kidney injury, hypocalcaemia and hypophosphataemia identified from Hospital Episode Statistics, and gastrointestinal events identified from Clinical Practice Research Datalink or Hospital Episode Statistics. Work package 4: annualised femoral neck bone mineral density percentage change.

RESULTS

Bisphosphonate use was associated with an excess risk of chronic kidney disease progression (subdistribution hazard ratio 1.12, 95% confidence interval 1.02 to 1.24) in work package 1, but did not increase the probability of other safety outcomes in work package 3. The results from work package 2 suggested that bisphosphonate use increased fracture risk (hazard ratio 1.25, 95% confidence interval 1.13 to 1.39) for hip fractures, but sensitivity analyses suggested that this was related to unresolved confounding. Conversely, work package 4 suggested that bisphosphonates improved bone mineral density, with an average 2.65% (95% confidence interval 1.32% to 3.99%) greater gain in femoral neck bone mineral density per year in bisphosphonate users than in matched non-users.

LIMITATIONS

Confounding by indication was a concern for the clinical effectiveness (i.e. work package 2) data. Bias analyses suggested that these findings were due to inappropriate adjustment for pre-treatment risk. work packages 3 and 4 were based on small numbers of events and participants, respectively.

CONCLUSIONS

Bisphosphonates were associated with a 12% excess risk of chronic kidney disease progression in participants with stage 3B+ chronic kidney disease. No other safety concerns were identified. Bisphosphonate therapy increased bone mineral density, but the research team failed to demonstrate antifracture effectiveness.

FUTURE WORK

Randomised controlled trial data are needed to demonstrate antifracture efficacy in patients with stage 3B+ chronic kidney disease. More safety analyses are needed to characterise the renal toxicity of bisphosphonates in stage 3A chronic kidney disease, possibly using observational data.

STUDY REGISTRATION

This study is registered as EUPAS10029.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 17. See the NIHR Journals Library website for further project information. The project was also supported by the National Institute for Health Research Biomedical Research Centre, Oxford.

Safety of Intravenous Bisphosphonates for the Treatment of Hypercalcemia in Patients With Preexisting Renal Dysfunction

BACKGROUND

Although intravenous (IV) bisphosphonates are first-line medications for the management of hypercalcemia, studies examining their use in patients with preexisting renal dysfunction are limited.

OBJECTIVE

The objective of this study is to describe the safety and efficacy of pamidronate and zoledronic acid in the treatment of hypercalcemia in patients with baseline renal dysfunction.

METHODS

A retrospective analysis was conducted of IV pamidronate and zoledronic acid in adult patients with hypercalcemia and creatinine clearance (CrCl) <60 mL/min. The primary endpoint was incidence of all-grade serum creatinine (SCr) elevations. Secondary endpoints included refractory hypercalcemia, hypocalcemia, osteonecrosis of the jaw (ONJ), corrected serum calcium (CSC) decrease ≥1.0 mg/dL by day 7 of bisphosphonate administration, and normalization of CSC ≤10.5 mg/dL by days 10 and 30.

RESULTS

A total of 113 patients were included (n = 55 pamidronate, n = 58 zoledronic acid). The primary endpoint of all-grade SCr elevation occurred in 28 (24.8%) patients. Grades 3/4 SCr elevations occurred in 10.9% of patients treated with pamidronate and 1.7% of patients receiving zoledronic acid. Approximately 16% and 14% of patients developed grades 1 and 2 hypocalcemia, respectively, and there were no cases of ONJ. Overall, 64.6% of patients achieved normalization of CSC by day 10, and there were no statistical differences between bisphosphonate type and renal function.

CONCLUSIONS AND RELEVANCE

The analysis suggests an association between IV bisphosphonates and increased rates of SCr elevations among patients with preexisting renal dysfunction. Future prospective studies are necessary to elucidate these findings.

Renal safety of 1-hour pamidronate infusion for breast cancer and multiple myeloma patients: comparison between clinical trials and population-based database

Purpose. The American Society of Clinical Oncology recommends infusion of pamidronate over 2 hours to avoid renal deterioration, although there are data to suggest that 1-hour infusions may be safe.

Methods, Prevalence of renal deterioration with 1-hour pamidronate infusions from a population database was compared to renal deterioration with 2-hour pamidronate infusions, in randomised, controlled, trials. A cost-minimisation analysis, comparing the 1-and 2-hour pamidronate infusions, and the 15-minute infusion of zoledronic acid, was performed with a sensitivity analysis that varied the opportunity cost of time in the treatment room.

Results. Renal deterioration occurred in 7.7% of 169 patients with multiple myeloma and metastatic breast cancer. There is no evidence that this differs from the 10% reported in randomised, controlled, trials (one-tailed binomial test, P=0.3874). A subgroup analysis showed that renal deterioration occurred in 15 and 1.1% of patients with multiple myeloma and metastatic breast cancer, respectively. The median increase in serum creatinine was 13 and 7% in the multiple myeloma and breast cancer groups, respectively. The respective costs/dose (drug/ labour/supplies) of pamidronate and zoledronic acid are $325 and $610. Cost neutrality occurs if the opportunity cost of chair time is $6.33/ minute for pamidronate 1-hour versus zoledronic acid, and $2.71/minute for pamidronate 2-hour versus zoledronic acid. If a median $4/minute is used, the respective costs of pamidronate 1-hour, 2-hour, and zoledronic acid infusions are $685, $925, and $790/cycle.

Conclusions. Prevalence of renal deterioration with 1-hour pamidronate infusions from a population database was not significantly different to 2-hour pamidronate infusions in clinical trials. Our findings suggest further support for the safety of 1-hour pamidronate infusions. Pamidronate via 1-hour infusion is less expensive than zoledronic acid.

Collapsing focal segmental glomerulosclerosis following long-term treatment with oral ibandronate: case report and review of literature

Background

Renal toxicity has been reported with bisphosphonates such as pamidronate and zolidronate but not with ibandronate, in the treatment of breast cancer patients with bone metastasis. One of the patterns of bisphosphonate-induced nephrotoxicity is focal segmental glomerulosclerosis (FSGS) or its morphological variant, collapsing focal segmental glomerulosclerosis (CFSGS).

Case presentation

We describe a breast cancer patient who developed heavy proteinuria (protein/creatinine ratio 9.1) and nephrotic syndrome following treatment with oral ibandronate for 29 months. CFSGS was proven by biopsy. There was no improvement 1 month after ibandronate was discontinued. Prednisone and tacrolimus were started and she experienced a decreased in proteinuria.

Conclusion

In patient who develops ibandronate-associated CFSGS, proteinuria appears to be at least partially reversible with the treatment of prednisone and/or tacrolimus if the syndrome is recognized early and ibandronate is stopped.

Drug-induced glomerular disease: direct cellular injury

The potential of medications to cause kidney injury is well known. Although nephrotoxicity is most commonly associated with injury in the tubulointerstitial compartment as either acute tubular necrosis or acute interstitial nephritis, a growing body of literature has also highlighted the potential for drug-induced glomerular lesions. This review surveys the three primary patterns of drug-induced glomerular diseases stratified by the cell type at which the glomerular lesion is focused: visceral epithelial cell (or podoctye) injury, endothelial cell injury, and mesangial cell injury. A number of commonly prescribed medications, including IFNs, bisphosphonates, nonsteroidal anti-inflammatory drugs, antiplatelet agents, and antiangiogenesis drugs, that are both prescribed and available over the counter, have been implicated in these iatrogenic forms of glomerular disease. Recognition of these drug-induced etiologies of glomerular disease and rapid discontinuation of the offending agent are critical to maximizing the likelihood of renal function recovery.

Side effects of bone-targeted therapies in advanced breast cancer

In up to 75% of cases, advanced breast cancer patients eventually develop bone metastases with often debilitating skeletal-related events (SREs). Osteoclast inhibitors are commonly used as therapeutic mainstay with clinical studies showing superiority of denosumab over bisphosphonates (e.g., zoledronate) for the prevention of SREs. The present review discusses the adverse event profile of these agents, and addresses the prevention and management of untoward side effects. Adverse events associated with osteoclast inhibitors comprise osteonecrosis of the jaw and hypocalcemia. Hypocalcemia is more common with denosumab, particularly in severe renal dysfunction. During therapy, the appropriate prevention of these adverse events includes close attention to dental health, avoidance of invasive dental procedures, supplementation with calcium and vitamin D unless patients are hypercalcemic, and regular monitoring of relevant serum values. Relating to the risk of nephrotoxicity, bisphosphonates but not denosumab have been incriminated. Therefore, serum creatinine levels should be checked prior to each dose of zoledronate, and in severe renal dysfunction (creatinine clearance < 30 ml/min) zoledronate is contraindicated anyway. Acute-phase reactions are particularly linked to bisphosphonates. Consequently, if these adverse events predominate, switching to denosumab is recommended.

Collapsing focal segmental glomerulosclerosis resulting from a single dose of zoledronate

Bisphosphonates are commonly used for the treatment of osteoporosis, Paget's disease, multiple myeloma and hypercalcemia. Collapsing focal segmental glomerulosclerosis (FSGS) is known to occur uncommonly with exposure to bisphosphonates, specifically pamidronate and alendronate; it has rarely and equivocally been reported with zoledronate therapy. We describe the case of a 36-year-old African American female with metastatic breast cancer who presented with nephrotic-range proteinuria and acute kidney injury within 2 weeks of exposure to a single dose of zoledronate. The patient had a partial recovery of her renal function and showed improved proteinuria to a subnephrotic level after discontinuing zoledronate. In contrast to 2 prior reports of zoledronate-induced collapsing FSGS, the causative role of the exposure described here is certain. Our case necessitates the addition of zoledronate to the list of known causes of collapsing FSGS. Furthermore, it highlights the importance of periodically monitoring renal function and urine protein excretion with the use of zoledronate, which allows prompt diagnosis and withdrawal of the drug to increase the probability of renal recovery.

Tolerability of intravenous pamidronate for the treatment of osteoporosis and other metabolic osteopathies: A retrospective analysis

BACKGROUND

Intravenous disodium pamidronate has been described in the treatment of several osteopathies. Although tolerability has been found to be good in clinical trials, some mild to serious adverse events (AEs) have been reported.

OBJECTIVES

The aims of this study were to analyze the toelrability of IV pamidronate in patients being treated for osteoporosis and other metabolic osteopathies and to describe particular patients with relative contraindications, because such cases are not commonly seen in daily clinical practice.

METHODS

We performed a retrospective analysis of patients with different osteopathies who were administered IV infusions of pamidronate at doses ranging from 15 to 90 mg/infusion and 15 to 900 mg/year. The study was conducted in patients who had received treatment at the Institute of Metabolic Investigations, University of Salvador, Buenos Aires, Argentina, between January 1995 and December 2003. To rule out dose-related AEs, a comparison was made between patients who received fewer IV infusions and had cumulative doses of 120 to 180 mg/y (less frequent administration [LFA] group) and those patients who received regular infusions and had cumulative doses of >180 mg/year (frequent administration [FA] group). To confirm data obtained from medical records and to assess the occurrence of AEs, attempts were made to interview all patients by phone. The following information was verified for each patient included in the study: the reason for treatment, documented evidence of current diagnostic criteria, and whether the dose administered was adequate to treat the patient's condition.

RESULTS

Six hundred eight patients (464 [76.3%]women, 144 [23.7%]men; mean [SD] age, 69 [10] years) with various osteopathies (osteoporosis, 367 [60.4%] of the patients; Paget's disease, 172 [28.3%]; Sudeck's disease, 63 [10.4%]; multiple myeloma, 3 [0.5%]; and bone metastases, 3 [0.5%]) were administered a total of 2933 IV infusions of pamidronate during the study period. We were able to confirm the clinical records of 69.4% (422/608) of the patients by telephone survey; 29.9% (124/415) of those patients experienced extraskeletal AEs (most commonly fever and flu-like symptoms [eg, headache, malaise, fatigue, chills, and asthenia]). The percentage of patients reporting AEs was significantly higher for the LFA group than that of the FA group (91.2 vs 19.5; P < 0.001), although factors other than the frequency of treatment might have had a bearing on this finding. All AEs were mild and transient in both groups of patients, and there were no reports of jaw osteonecrosis in either group. It should be noted that although LFA patients received lower doses of pamidronate per infusion than the FA group, they had higher cumulative doses/year. Biochemical variables for the entire study population were compared with baseline measurements, and no significant changes in mean values were observed. Both serum calcium and 25-hydroxy vitamin D levels remained within normal ranges. On the other hand, there was a transient decrease in white blood cell count (WBCC) in 73 (12.0%) patients, and leukopenia was observed in 8 (1.3%) patients. However, 5 of the 6 patients who were leukopenic at the beginning of treatment had normal WBCCs during follow-up. Platelet count decreased significantly in 20 (3.3%) patients, and 5 (0.8%) patients developed thrombocytopenia. Serum creatinine (sCreat) levels increased significantly in 91 (15.0%) patients. This increase was transient and within normal limits (0.6-1.2 mg/dL) in 79 (86.8%) of those patients but persistent in the other 12 (13.2%), all of whom received higher doses of pamidronate or had other risk factors for renal failure such as advanced age, diabetes, multiple myeloma, or an obstructor disease. Baseline sCreat level for 7 of these 12 patients was >1.20 mg/dL.

CONCLUSIONS

Pamidronate administered IV was well tolerated when used for treating osteoporosis or other metabolic osteopathies in our study population. The clinical AEs observed with IV pamidronate administration were not serious and hematologic changes were mild, transient, and not associated with dose, time of treatment, or any particular underlying disease. An increase in sCreat level was the most frequent biochemical complication and was found in patients with additional risk factors for renal failure and particular diseases. Whether certain patients with risk factors for osteoporosis may require even fewer IV administrations of the drug is an issue that remains to be elucidated.

Approach to diagnosis and treatment of hypercalcemia in a patient with malignancy

Hypercalcemia is a common complication of malignancy and portends a worse prognosis. It causes a variety of symptoms in patients, which can range from confusion and polyuria to coma and death. There are 4 broad mechanistic categories to classify hypercalcemia of malignancy: local osteolysis secondary to metastatic cancer or multiple myeloma, excess parathyroid-related hormone, excess 1,25-dihydroxyvitamin D production, and ectopic parathyroid hormone production. Volume expansion with normal saline solution and treatment with intravenous bisphosphonates to decrease osteoclast-mediated bone destruction are effective initial therapies. Calcitonin, gallium nitrate, and corticosteroids can serve as adjunctive therapies. Denosumab is an attractive therapeutic option for refractory cases of hypercalcemia, although more data are required before this therapy can be recommended.

International Myeloma Working Group recommendations for the treatment of multiple myeloma-related bone disease

PURPOSE

The aim of the International Myeloma Working Group was to develop practice recommendations for the management of multiple myeloma (MM) -related bone disease.

METHODOLOGY

An interdisciplinary panel of clinical experts on MM and myeloma bone disease developed recommendations based on published data through August 2012. Expert consensus was used to propose additional recommendations in situations where there were insufficient published data. Levels of evidence and grades of recommendations were assigned and approved by panel members.

RECOMMENDATIONS

Bisphosphonates (BPs) should be considered in all patients with MM receiving first-line antimyeloma therapy, regardless of presence of osteolytic bone lesions on conventional radiography. However, it is unknown if BPs offer any advantage in patients with no bone disease assessed by magnetic resonance imaging or positron emission tomography/computed tomography. Intravenous (IV) zoledronic acid (ZOL) or pamidronate (PAM) is recommended for preventing skeletal-related events in patients with MM. ZOL is preferred over oral clodronate in newly diagnosed patients with MM because of its potential antimyeloma effects and survival benefits. BPs should be administered every 3 to 4 weeks IV during initial therapy. ZOL or PAM should be continued in patients with active disease and should be resumed after disease relapse, if discontinued in patients achieving complete or very good partial response. BPs are well tolerated, but preventive strategies must be instituted to avoid renal toxicity or osteonecrosis of the jaw. Kyphoplasty should be considered for symptomatic vertebral compression fractures. Low-dose radiation therapy can be used for palliation of uncontrolled pain, impending pathologic fracture, or spinal cord compression. Orthopedic consultation should be sought for long-bone fractures, spinal cord compression, and vertebral column instability.

Onco-nephrology: the pathophysiology and treatment of malignancy-associated hypercalcemia

Hypercalcemia complicates the course of 10%-30% of all patients with malignancies and can be a sign of very poor prognosis and advanced malignancy. Prompt recognition of the nonspecific signs and symptoms of hypercalcemia and institution of therapy can be lifesaving, affording the opportunity to address the underlying etiology. The mechanisms of malignancy-associated hypercalcemia generally fall into three categories: humoral hypercalcemia due to secreted factors (such as parathyroid-related hormone), local osteolysis due to tumor invasion of bone, and absorptive hypercalcemia due to excess vitamin D produced by malignancies. The mainstays of therapy for hypercalcemia are aggressive intravenous volume expansion with saline, bisphosphonate therapy, and perhaps loop diuretics. Adjunctive therapy may include calcitonin and corticosteroids. In refractory cases, gallium nitrate and perhaps denosumab are alternatives. In patients presenting with severe AKI, hemodialysis with a low-calcium bath can be effective. In most cases, therapy normalizes calcium levels and allows for palliation or curative therapy of the malignancy.

Renal complications in multiple myeloma and related disorders: survivorship care plan of the International Myeloma Foundation Nurse Leadership Board

Kidney dysfunction is a common clinical feature of symptomatic multiple myeloma. Some degree of renal insufficiency or renal failure is present at diagnosis or will occur during the course of the disease and, if not reversed, will adversely affect overall survival and quality of life. Chronic insults to the kidneys from other illnesses, treatment, or multiple myeloma itself can further damage renal function and increase the risk for additional complications, such as anemia. Patients with multiple myeloma who have light chain (Bence Jones protein) proteinuria may experience renal failure or progress to end-stage renal disease (ESRD) and require dialysis because of light chain cast nephropathy. Kidney failure in patients with presumed multiple myeloma also may result from amyloidosis, light chain deposition disease, or acute tubular necrosis caused by nephrotoxic agents; therefore, identification of patients at risk for kidney damage is essential. The International Myeloma Foundation's Nurse Leadership Board has developed practice recommendations for screening renal function, identifying positive and negative contributing risk and environmental factors, selecting appropriate therapies and supportive care measures to decrease progression to ESRD, and enacting dialysis to reduce and manage renal complications in patients with multiple myeloma.

Reversibility of pamidronate-associated glomerulosclerosis

Bisphosphonates such as pamidronate are widely used in the treatment of patients with lytic bony lesions secondary to breast cancer or multiple myeloma, yet they have been associated with deterioration of renal function and histopathological changes in the kidney. There have been recent reports associating the use of pamidronate with the development of the collapsing variant of focal segmental glomerulosclerosis (CFSGS), a rapidly progressive variant of focal segmental glomerulosclerosis that leads to end-stage renal disease. We describe five patients who developed worsening renal function, proteinuria, and nephrotic syndrome while taking pamidronate; three of them had biopsy-proven CFSGS. Pamidronate was discontinued, and a longitudinal follow-up was performed for 10 to 23 months. One patient was able to discontinue hemodialysis, and all patients experienced improvement in renal function and a decrease in proteinuria. In some patients who develop pamidronate-associated CFSGS, renal damage appears to be reversible if the syndrome is recognized early and pamidronate is stopped.

Nephrotic syndrome and renal failure in a patient with metastatic breast cancer

This report presents a case of nephrotic syndrome and renal failure that developed in a 53-year-old female with metastatic breast carcinoma. She was diagnosed to have osteolytic bone metastases 5 years prior to admission, and had been administered pamidronate with a total dose of approximately 6800 mg. A renal biopsy revealed tubulointerstitial damage and marked wrinkling and retraction of the glomerular basement membrane with hypertrophy and hyperplasia of the epithelial cells, compatible with the collapsing form of focal segmental glomerulosclerosis (FSGS). Despite the discontinuation of pamidronate after admission, her renal function gradually decreased. She was finally managed with continuous palliative care for advanced malignancy through a shared effort, and died 96 days after undergoing the renal biopsy. Although the clinical impact of the pamidronate-associated kidney injury on the longitudinal changes in renal function remains to be delineated, it is therefore reasonable to consider that the collapsing FSGS associated with tubulointerstitial damage may have resulted in the irreversible renal injuries that were observed in the current case. Further studies and accumulated experience with renal biopsy are required to better determine the relationship between pathological alterations and prognostic characteristics among patients with pamidronate-associated renal impairments.

Collapsing glomerulopathy in Portugal: a review of the histological and clinical findings in HIV and non-HIV patients

BACKGROUND

Collapsing glomerulopathy (CG) is a glomerulonephritis seen in association with human immunodeficiency virus (HIV) infection, known as HIV-associated nephropathy (HIVAN), and less frequently observed in non-HIV-infected patients. Method. The aim of this study was to review the histological and clinical findings of all CG diagnosed since 1981 in our laboratory. Result. Since 1981, 18 kidney biopsies with collapsing features were diagnosed among 6130 biopsies performed: 72.2% (n = 13) males, mean age 33.8 ± 9.7 years, 61.1% (n = 11) of black ethnic origin. HIV infection was present in 10 patients. Mean serum creatinine (Scr) was 4.7 ± 2.5 mg/dL, and mean proteinuria was 6.1 ± 5 g/24 h. Both HIVAN and non-HIVAN patients were similar in terms of age, gender and dialysis requirement. In the HIVAN population, African origin was predominant and more frequent than in the non-HIVAN population, Scr was higher and proteinuria was less severe. Interstitial infiltrate, interstitial fibrosis and tubular atrophy were severe, and the presence of microcystic dilatation of renal tubules was more common. Immunofluorescence was positive in six patients. In the non-HIVAN population, this histological lesion was related to an infectious illness in 6/8 patients and to the use of illegal oral drugs in one patient. Interstitial infiltrate, interstitial fibrosis and tubular atrophy presented as moderate to severe, and tubular atrophy correlated with dialysis requirement. Mesangial proliferation was present in 3/8 patients, with C3 and IgA deposits.

CONCLUSION

CG is a rare podocytopathy. In this study, the association between infection and CG is evident, and we may suggest that infections could, in a direct or indirect manner, be a trigger of podocyte injury.

Adverse effects of bisphosphonates

Use of bisphosphonates has been growing steadily in the last decade. This follows the introduction of simpler dosing regimes, the availability of lower-priced generics, and concerns about the safety of hormone-replacement therapy. Bisphosphonates have a relatively good safety record and are tolerated by the majority of patients, but serious adverse events have been recorded in some cases. Only the most common of adverse effects are robustly observable in clinical trials. In general, studies were not powered to detect effects that were lower in incidence than fractures. This review of adverse events in bisphosphonate-treated patients was based on published information from case reports, case series, claims databases, national databases, surveys, adverse event reporting databases, and single or pooled clinical trials. The most common acute adverse events with bisphosphonates for osteoporosis are gastrointestinal discomfort and acute influenza-like illness. Renal complications are very rare with oral bisphosphonates and rare with i.v. bisphosphonates when used appropriately. Based on our current knowledge, skeletal events in the form of osteonecrosis of the jaw and atypical fragility fractures are rare compared with the risk of osteoporotic fractures, at least in patients with the same risk of fractures as those in the phase III trials. It is biologically plausible that atypical fragility fractures could follow from suppression of bone remodeling, but high-quality studies proving causality are lacking. Physicians are advised to critically reassess BMD and risk profile after 3-5 years of therapy to avoid treatment in patients at low risk.

Safe and tolerable one-hour pamidronate infusion for multiple myeloma patients

Background:

Once a month, patients with multiple myeloma received an infusion of bisphosphonates, principally to reduce osteoclastic bone resorption. Recommended infusion time for pamidronate is 2 hours in the US and 4 hours in Europe because of its potential nephrotoxicity. From 2003, a 90 mg infusion of pamidronate was provided over 1 hour to patients with no pre-existing renal impairment, in the Daily Care Unit at Uddevalla Hospital.

Method:

Retrospective analysis of the renal deterioration, serum calcium, and adverse effects in patients with multiple myeloma treated with 1-hour pamidronate 90 mg infusion from January 2003 to April 2007.

Results:

Seventy-nine patients provided valuable data. A total number of 846 infusions were given and the median number of infusion to each patient was 11. Significant creatinine elevation was seen in 7 patients (8.9%), after 19 infusions (2.2%). Renal deterioration occurred in 5 of these 7 patients, which was related to progress of the myeloma or opportunistic infections. Prevalence of infusion-related events was 0.8% and the mean total S-Ca was 0.05 mmol/L lower than the baseline.

Conclusion:

Few events of renal deterioration, hypocalcemia, or other adverse effects resulted from a 1-hour pamidronate 90 mg infusion for multiple myeloma patients with no pre-existing renal impairment.

Drug-induced Kidney Disease – Pathology and Current Concepts

The kidneys can be damaged by a large number of therapeutic agents. The aim of this article is to discuss the pathological features of drug-induced renal disease as diagnosed by kidney biopsy. The literature is reviewed and cases seen by the authors that have a known drug association are analysed. Mechanisms of injury are varied and all renal structures may be affected. The tubulointerstitial compartment is most frequently involved, but glomerular and vascular lesions are seen in a significant proportion of cases. Key words: Drug, Kidney, Nephrotoxicity, Pathology

[Bisphosphonate-induced collapsing focal segmental glomerulosclerosis; two clinical cases and literature review]

Collapsing focal segmental glomerulosclerosis is well described in its idiopathic form, mostly seen in young African American patients, and in association with HIV virus. Its clinical presentation typically includes proteinuria and renal failure rapidly progressing to end stage renal disease. However, a new form has recently been described related to treatment with high doses of intravenous bisphosphonates, especially pamidronate. We report two cases of collapsing focal segmental glomerulosclerosis in patients treated with intravenous pamidronate. In opposition to previous reports, interruption of pamidronate administration did not improve renal function. The latter should be evaluated before initiating treatment with bisphosphonates and regularly monitored. For patients with chronic kidney disease, introduction of bisphosphonates should be reconsidered given the risk of rapid progression to end stage renal disease and the lack of evidence for reduction of fracture risk in this population.

Pamidronate in the prevention of bone loss after liver transplantation: a randomized controlled trial

Rapid bone loss and high rates of fractures occur following liver transplantation. To analyze the effect of intravenous pamidronate on bone loss after liver transplantation. A randomized, double-blind, placebo-controlled study was performed. Seventy-nine patients were randomized to two groups of treatment: the pamidronate group (n = 38) was treated with 90 mg/IV of pamidronate within the first 2 weeks and at 3 months after transplantation; the placebo group (n = 41) received glucose infusions at the same time points. All patients received calcium and vitamin D. Bone mineral density (BMD) at the lumbar spine (L(2)-L(4)) and proximal femur using dual energy X-ray absorptiometry and also spinal X-rays were performed before, and at 6 and 12 months after liver transplantation. Biochemical and hormonal determinations were performed previous to transplantation, at 24 h before and after treatment, as well as at 6 and 12 months after liver transplantation. At 12 months after transplantation, there were significant differences in lumbar BMD changes (6 months: pamidronate 1.6% vs. placebo 0.8%, P = NS; 12 months: pamidronate 2.9% vs. placebo 1%, P < 0.05). Femoral neck BMD decreased in the pamidronate- and placebo groups during the first 6 months (6 months: pamidronate -3.1% vs. placebo -2.9%, P = NS; 12 months: pamidronate -3.2% vs. placebo -3.1%, P = NS). BMD at the trochanter remained stable in the pamidronate group, whilst a reduction was observed in the placebo group at 6 months (6 months: pamidronate -0.7% vs. placebo -3.7%, P < 0.05; 12 months: pamidronate -0.5% vs. placebo -1.2%, P = NS). Moreover, no significant differences in the incidence of fractures, serum parathyroid hormone and serum 25-hydroxyvitamin D values between both groups were found. Pamidronate did not increase the risk of serious adverse events. The results of this study show that 90 mg of intravenous pamidronate within the first 2 weeks and at 3 months following liver transplantation preserve lumbar bone mass during the first year, without significant adverse events. However, pamidronate does not reduce bone loss at the femoral neck and furthermore it does not reduce skeletal fractures.

Bisphosphonate nephrotoxicity

Bisphosphonates are valuable agents for the treatment of post-menopausal osteoporosis (PMO), hypercalcemia of malignancy, and osteolytic bone metastases. Oral bisphosphonates are used mainly to treat PMO and are not associated with significant nephrotoxicity. In contrast, nephrotoxicity is a significant potential limiting factor to the use of intravenous (IV) bisphosphonates, and the nephrotoxicity is both dose-dependent and infusion time-dependent. The two main IV bisphosphonates available to treat hypercalcemia of malignancy and osteolytic bone disease in the United States are zoledronate and pamidronate. Patterns of nephrotoxicity described with these agents include toxic acute tubular necrosis and collapsing focal segmental glomerulosclerosis, respectively. With both of these agents, severe nephrotoxicity can be largely avoided by stringent adherence to guidelines for monitoring serum creatinine prior to each treatment, temporarily withholding therapy in the setting of renal insufficiency, and adjusting doses in patients with pre-existing chronic kidney disease. In patients with PMO, zoledronate and pamidronate are associated with significantly less nephrotoxicity, which undoubtedly relates to the lower doses and longer dosing intervals employed for this indication. Ibandronate is approved in the US for treatment of PMO and in Europe for treatment of PMO and malignancy-associated bone disease. Available data suggest that ibandronate has a safe renal profile without evidence of nephrotoxicity, even in patients with abnormal baseline kidney function.

Oral versus intravenous ibandronic acid: a comparison of treatment options for metastatic bone disease

PURPOSE

This trial is the first to compare directly the clinical response to and safety of oral and intravenous (IV) ibandronic acid for metastatic bone disease.

METHODS

Patients > or =18 years with breast, prostate, lung, urogenital or colon cancer received IV ibandronic acid 6 mg infused over 15 min every 28 days or oral ibandronic acid 50 mg/day. Clinical response was determined using bone scintigraphy, radiography and serum C-terminal telopeptide of type I collagen (S-CTX) at months 3-6. Adverse events and biochemical safety measures were recorded.

RESULTS

A total of 84.6 and 88.5% of patients had a complete/partial response to IV and oral ibandronic acid, respectively. Median percentage decreases in S-CTX were -39 and -35%, respectively. Bone pain scores decreased and analgesic use increased from month 0-3 and were stable from months 3-6. Both formulations improved physical and functioning scores.

CONCLUSION

Oral and IV ibandronic acid for bone metastases have similar efficacy and tolerability.

Collapsing focal segmental glomerulosclerosis in a liver transplant recipient on alendronate

We describe a case of collapsing focal segmental glomerulosclerosis and severe kidney dysfunction in a liver transplant recipient after the initiation of alendronate for osteopenia. In view of the increasing incidence of chronic kidney disease in long-term liver transplant patients, bisphosphonates need to be used with caution in these patients. The usefulness of bisphosphonates for the prevention of early bone loss after liver transplantation is increasingly reported. However, there is little information on the safety and efficacy of these drugs when used in the later stages of liver transplant, particularly in the presence of chronic kidney disease. Bisphosphonates are excreted unchanged via the kidneys after reaching the systemic circulation. Some cases of severe kidney injury, in particular collapsing focal segmental glomerulosclerosis, have been described that are associated with the use of pamidronate. Alendronate, a widely used bisphosphonate in transplant patients, has not been related to kidney toxicity. We describe a case of collapsing focal segmental glomerulosclerosis and severe kidney dysfunction in a liver transplant recipient soon after the initiation of alendronate for osteopenia. Possible pathogenetic mechanisms are discussed. In view of the increasing incidence of chronic kidney disease in long-term liver transplant patients, bisphosphonate need to be used with caution in patients with a low glomerular filtration rate.

Ibandronate: Its Role in Metastatic Breast Cancer

Bisphosphonates are the most effective agents for treating and/or preventing complications of bone metastases and are the standard of care in this setting. Currently, four bisphosphonates are available for metastatic bone disease (MBD): clodronate, pamidronate, zoledronic acid, and ibandronate. Although all four of these bisphosphonates have been shown to reduce the incidence of skeletal-related events in patients with bone metastases, there are substantial differences among these agents in their potency, dose and route of administration, and side effects. Ibandronate and zoledronic acid, the two newer aminobisphosphonates, appear to have similar biochemical efficacies when phase III trial data are compared. Both agents were equally effective in reducing markers of bone resorption in the only prospective comparative trial carried out to date, but no data on relative clinical efficacy are available from head-to-head comparisons. Both the oral and i.v. formulations of ibandronate have also shown long-term efficacy in managing metastatic bone pain (MBP), but the onset of action of standard bisphosphonate treatment is not sufficient when rapid relief of pain is required. Because of its favorable renal safety profile, i.v. ibandronate can be administered daily for 3 days, as a so-called "loading dose." This dosing regimen has allowed rapid and effective relief of MBP without the unwanted side effects associated with opioids and other analgesics. Ibandronate is thus an effective, flexible, and well-tolerated bisphosphonate that can meet the varying requirements of patients with MBD.

Management of the adverse effects associated with intravenous bisphosphonates

Intravenous bisphosphonates are widely used to treat hypercalcemia and to reduce skeletal-related morbidity among cancer patients. However, serious complications, generally occurring in less than 2% of patients participated in phase III clinical trials, including acute systemic inflammatory reaction, ocular inflammation, renal failure, nephrotic syndrome, electrolyte imbalance, and osteonecrosis of the maxilla and mandible have all been increasingly reported. Yet, strategies to deal with these complications are becoming clear. Acute systemic inflammatory reaction is often self-limited and becomes less intense during subsequent treatments. For patients who develop ocular symptoms, prompt ophthalmologic evaluation is crucial to determine the safety of a subsequent bisphosphonate therapy. Patients who receive long-term pamidronate should be evaluated at intervals for early sign of nephritic syndrome as timely cessation of the agent may result in a full recovery. To reduce the risk of severe electrolyte abnormalities, particularly hypocalcemia, correcting any pre-treatment electrolyte abnormality and supplementing vitamin D and calcium may be helpful. Finally, to reduce the risk of osteonecrosis of the maxilla and mandible, obtaining a full dental evaluation before treatment and avoidance of invasive dental procedures is suggested. The three commonly used intravenous bisphosphonates (pamidronate, zoledronic acid, and ibandronate), are generally safe; ibandronate has to date been the least reported to be associated with renal side effects. As clinical indications of intravenous bisphosphonates continue to expand, prescribing clinicians should be familiar with these possible adverse effects and discuss them with patients before commencing or continuing on therapy.

Randomized phase III trial of capecitabine compared with bevacizumab plus capecitabine in patients with previously treated metastatic breast cancer

PURPOSE

This randomized phase III trial compared the efficacy and safety of capecitabine with or without bevacizumab, a monoclonal antibody to vascular endothelial growth factor, in patients with metastatic breast cancer previously treated with an anthracycline and a taxane.

PATIENTS AND METHODS

Patients were randomly assigned to receive capecitabine (2,500 mg/m2/d) twice daily on day 1 through 14 every 3 weeks, alone or in combination with bevacizumab (15 mg/kg) on day 1. The primary end point was progression-free survival (PFS), as determined by an independent review facility.

RESULTS

From November 2000 to March 2002, 462 patients were enrolled. Treatment arms were balanced. No significant differences were found in the incidence of diarrhea, hand-foot syndrome, thromboembolic events, or serious bleeding episodes between treatment groups. Of other grade 3 or 4 adverse events, only hypertension requiring treatment (17.9% v 0.5%) was more frequent in patients receiving bevacizumab. Combination therapy significantly increased the response rates (19.8% v 9.1%; P = .001); however, this did not result in a longer PFS (4.86 v 4.17 months; hazard ratio = 0.98). Overall survival (15.1 v 14.5 months) and time to deterioration in quality of life as measured by the Functional Assessment Of Cancer Treatment--Breast were comparable in both treatment groups.

CONCLUSION

Bevacizumab was well tolerated in this heavily pretreated patient population. Although the addition of bevacizumab to capecitabine produced a significant increase in response rates, this did not translate into improved PFS or overall survival.

Podocyte injury associated glomerulopathies induced by pamidronate

BACKGROUND

Pamidronate has been demonstrated to decrease bone-related complications in multiple myeloma and delay progression of the disease. This has led to its use in supportive and maintenance therapy of myeloma in conjunction with steroids and chemotherapy. It has also been selectively used in patients with breast cancer and other neoplasms.

METHODS

We report on five patients who developed glomerular disease induced by pamidronate. Pamidronate was the only drug common to all patients. Tests for hepatitis B and C and human immunodeficiency virus (HIV) were negative for all patients. The first two patients received a high dose of pamidronate for 8 weeks, whereas the other three patients were on monthly therapy for a prolonged period of time. Sources of data included chart review and pathologic analysis of kidney biopsy.

RESULTS

Three patients were female and two were males and all were Caucasian, ranging in age from 58 to 71 years. Renal biopsy findings included minimal change disease in two, focal segmental glomerulosclerosis in two, and collapsing focal segmental glomerulosclerosis in one. Immunofluorescence was essentially negative in all cases. Electron microscopy showed variable podocyte injury and extensive foot process effacement. There was no evidence of multiple myeloma-related renal disease. After the biopsy, pamidronate was discontinued and renal function stabilized in all patients except the one with the collapsing variant of focal segmental glomerulosclerosis who required hemodialysis. Three patients had resolution of proteinuria, one patient continued to have proteinuria without deterioration in renal function.

CONCLUSION

Pamidronate has been mainly associated with collapsing focal segmental glomerulosclerosis. This report expands that relationship and adds other glomerular diseases linked with podocyte injury. Additional studies are needed to define the cause of the variability of renal histology with this agent.

Collapsing glomerulopathy

Collapsing glomerulopathy is a morphologic variant of focal segmental glomerulosclerosis (FSGS) characterized by segmental and global collapse of the glomerular capillaries, marked hypertrophy and hyperplasia of podocytes, and severe tubulointerstitial disease. The cause of this disorder is unknown, but nearly identical pathologic findings are present in idiopathic collapsing glomerulopathy and human immunodeficiency virus (HIV)-associated nephropathy, and collapsing glomerulopathy has been associated with parvovirus B19 infection and treatment with pamidronate. The pathogenesis of collapsing glomerulopathy involves visceral epithelial cell injury leading to cell cycle dysregulation and a proliferative phenotype. Clinically, collapsing glomerulopathy is characterized by black racial predominance, a high incidence of nephrotic syndrome, and rapidly progressive renal failure. Collapsing glomerulopathy also may recur after renal transplantation or present de novo, often leading to loss of the allograft. The optimal treatment for collapsing glomerulopathy is unknown. Treatments may include steroids or cyclosporine in addition to aggressive blood pressure control, angiotensin converting enzyme inhibitors and/or angiotensin II receptor blockers, and lipid lowering agents. The role of other immunosuppressive agents such as mycophenolate mofetil in the treatment of collapsing FSGS remains to be defined. Prospective clinical trials are needed to define optimal therapy of this aggressive form of FSGS.

Bisphosphonates

Bisphosphonates now occupy a prominent position among therapeutic options for the prevention and treatment of various forms of osteoporosis. Their clinical profile of bone-specific efficacy, rapid response, protection from both spine and hip fractures in patients with osteoporosis, and excellent tolerability is all that can be expected of an anti-remodeling drug. Even in the era of anabolic agents, bisphosphonates will continue to be important treatment options. It is not possible to compare or contrast the clinical effectiveness of the various bisphosphonates on the basis of existing data. Despite marked differences in the in vitro potency of drugs, the clinical responses to each of the bisphosphonates discussed above are similar. New bisphosphonates may not be more effective but will provide different tolerability profiles and different routes of administration, thereby increasing the number of patients in whom bisphosphonates can be used. Having these effective agents challenges clinicians to identify the most appropriate patients for bisphosphonate use and to develop strategies to improve acceptance of and adherence to these useful agents.