Toxic acute tubular necrosis following treatment with zoledronate (Zometa)

Can bisphosphonates play a role in the treatment of children with chronic kidney disease?

In patients with chronic kidney disease (CKD) renal osteodystrophy, in the form of either low- or high-turnover bone disease, is quite common. While renal transplantation is expected to reverse renal osteodystrophy, long-term treatment with glucocorticoids before and/or after transplantation may lead to osteoporosis instead. Osteoporosis is defined as a skeletal disease with low bone mineral density, microarchitectural deterioration, and concomitant fragility. In adults, bisphosphonates are widely used to treat osteoporosis and other diseases associated with excessive bone resorption. In pediatric CKD patients the efficacy and safety of these drugs have not yet been addressed adequately and thus no evidence-based recommendations regarding the optimal type of bisphosphonate, dosage, or duration of therapy are available. Furthermore, while in adults the determination of areal bone mineral density is sufficient to diagnose osteoporosis, this is not the case in children. Instead, in pediatric patients, careful morphological assessment of bone structure and formation is required. Indeed, data from studies with uremic rats indicated that bisphosphonates, via a deceleration of bone turnover, have the potential not only to aggravate pre-existing adynamic bone disease, but also to impair longitudinal growth. Thus, the widespread use of bisphosphonates in children with CKD should be discouraged until the risks and benefits have been carefully elucidated in clinical trials.

Safety of long-term bisphosphonate therapy for the management of osteoporosis

Drugs in the bisphosphonate class are the most commonly prescribed therapeutic agents for the treatment of osteoporosis. Prospective, randomized, placebo-controlled clinical trials have demonstrated efficacy in reducing fracture risk, with favourable safety profiles, in women with postmenopausal osteoporosis. However, long-term use in clinical practice has been associated with reports of undesirable events not previously recognized. These have included gastrointestinal intolerance, osteonecrosis of the jaw, atypical femur fractures, oesophageal cancer, atrial fibrillation and chronic musculoskeletal pain. Physicians must be alert to newly recognized safety concerns, understand the level of evidence supporting them and be able to effectively communicate the balance of expected benefit and potential risk to patients. Usually, post-marketing adverse events are first presented as case reports or observational studies with variable levels of supporting evidence for plausibility, pathophysiology and causality. Widespread coverage in the news media, which can be alarming to patients and their physicians, may not present a balanced view of the proven benefits, the uncertain risks of therapy and the relative magnitude of these events. There may be confusion about the risks associated with bisphosphonate use for the treatment of osteoporosis versus treatment of other conditions, such as cancer, which typically involves a very different patient population and different doses or frequency of drug administration. Often reports of possible adverse events do not provide information on the number of patients exposed to the drug in proportion to the reported adverse event, or do not describe the incidence of the adverse event in a comparator population not exposed to the drug. Gastrointestinal intolerance with oral bisphosphonates, and hypocalcaemia, acute phase reactions and renal toxicity with intravenous bisphosphonates are characterized by biological plausibility and demonstration of causality. Safety concerns with uncertain biological plausibility and unproven causality include osteonecrosis of the jaw, atypical femur fractures, oesophageal cancer and ocular inflammation. Suspected concerns that are unlikely to be causally related include atrial fibrillation and hepatotoxicity. When making the decision to use a bisphosphonate for the treatment of osteoporosis, the balance between benefit and potential risks according to clinical circumstances of each patient should be considered.

Recent advances in diagnosis and treatment of acute kidney injury in patients with cancer

Acute Kidney Injury (AKI) is a common complication in patients with cancer and even though there are many causes of renal failure in this population the classical classification of prerenal, renal, and postrenal is useful as a diagnostic guide. Important risk factors for AKI are dehydration, use of nephrotoxic drugs, preexisting renal impairment and large tumor burden. The development of AKI is associated with poor prognosis but early recognition and treatment initiation are associated with better outcomes in this population.

The risk of cumulative renal effects of intravenous bisphosphonates

Some level of renal dysfunction is common in patients with cancer. This could be a result of an age-related kidney function decrease, the underlying disease (eg, multiple myeloma), or the effects of nephrotoxic medications. Some intravenous (I.V.) bisphosphonates have been associated with occasional renal toxicity in the clinical setting. Therefore, the choice of an I.V. bisphosphonate should take into account the risk of renal deterioration. Preclinical studies also suggest that there might be considerable differences between the renal safety profiles of commonly used I.V. bisphosphonates. Variations in the risk of histopathologic damage and the ability to cause cumulative toxicity have been observed in comparative preclinical studies of I.V. bisphosphonates. The reasons for these apparent differences are not fully understood. Research shows that renal safety profiles might be influenced by pharmacokinetic properties, such as renal tissue half-life, protein binding, and intracellular potency. Preclinical analyses are warranted in order to confirm and evaluate these differences between bisphosphonates.

[Treatment of metastatic bone disease and treatment-induced osteoporosis in prostate cancer. Evolution of osteoprotective strategies]

Patients with prostate cancer and bone metastases on average experience one skeletal-related event per year. To avoid complications caused by bone metastases and androgen deprivation therapy-induced osteoporosis, which lead to significant increases in costs and mortality, bone metabolism can be influenced in several ways. Bisphosphonates, which directly inhibit signalling pathways in osteoclasts, can reduce the rate of skeletal-related events in metastatic prostate cancer. The RANKL antibody denosumab inhibits the crosstalk between osteoblasts, osteoclasts and tumour cells and has been shown to reduce the rate of vertebral fractures in patients with treatment-induced osteoporosis. Furthermore, it has been recently shown to prevent skeletal-related events in prostate cancer patients with metastatic bone disease. In patients with castration resistant prostate cancer, denosumab prolongs bone-metastasis-free-survival. Whereas ample data are available about side effects of bisphosphonates, limited evidence exists about the long-term safety profile of denosumab. Therefore, a thorough patient selection is advocated for therapeutic application of denosumab in patients with prostate cancer.

Modern management of malignant hypercalcemia

Hypercalcemia occurs in 10% to 20% of those with advanced cancer. It is considered an oncologic emergency. Presenting symptoms include common gastrointestinal symptoms that may be difficult to differentiate from tumor or treatment-related symptoms. These include nausea, vomiting, and constipation. As levels increase or if development is rapid, neuropsychiatric symptoms such as delirium can develop. Untreated it will lead to coma and death. Current preferred therapies are the bisphosphonate agents, zoledronate and pamidronate with saline rehydration.

The kidney and bisphosphonates

Bisphosphonates are eliminated from the human body by the kidney. Renal clearance is both by glomerular filtration and proximal tubular secretion. Bisphosphonates given rapidly in high doses in animal models have induced a variety of adverse renal effects, from glomerular sclerosis to acute tubular necrosis. Nevertheless in the doses that are registered for the management of postmenopausal osteoporosis (PMO), oral bisphosphonates have never been shown to adversely affect the kidney, even (in post-hoc analysis of clinical trial data) down to estimated glomerular filtration rates of 15 ml/min. In addition fracture risk reduction has also been observed in these populations with stage 4 chronic kidney disease (CKD) with age-related reductions in glomerular filtration rate (GFR). Intravenous zoledronic acid is safe when the infusion rate is no faster than 15 min though there have been short-term (days 9-11 post-infusion) increases in serum creatinine concentrations in a small sub-set of patients from the postmenopausal registration trials. For these reasons intravenous zoledronic acid should be avoided in patients with GFR levels <35 ml/min; and the patients should be well hydrated and have avoided the concomitant use of any agent that may impair renal function. Intravenous ibandronate has not to date been reported to induce acute changes in serum creatinine concentrations in the PMO clinical trial data, but the lack of head-to-head comparative data between ibandronate and zoledronic acid precludes knowing if one intravenous bisphosphonate is safer than the other. In patients with GFR levels <30-35 ml/min, the correct diagnosis of osteoporosis becomes more complex since other forms of renal bone disease, which require different management strategies than osteoporosis, need to be excluded before the assumption can be made that fractures and/or low bone mass are due to osteoporosis. In addition, in patients who may have pre-existing adynamic renal bone disease, there is a lack of evidence of any beneficial effect or harm by reducing bone turnover by any pharmacological agent, including bisphosphonates on bone strength or vascular calcification. Bisphosphonates are safe and effective for the management of osteoporosis when used in the right dose and in the right patient population for the right duration.

The role of bisphosphonates in multiple myeloma: mechanisms, side effects, and the future

Zoledronic acid and pamidronate are two potent anticatabolic nitrogen-containing bisphosphonates (BPs) used extensively in diseases with high bone turnover such as multiple myeloma (MM). In this review we focus on their biology and their current and future use in MM, and highlight some of the most common and emerging side effects. Although the primary target cells for BPs are osteoclasts, new insights suggest other cell types of the bone microenvironment as possible targets, including osteoblasts, endothelial cells, immune cells, and cancer cells. Here, we focus on the current guidelines for the use of BPs in MM and address side effects such as renal toxicity, osteonecrosis of the jaw, and low-energy fractures. Finally, we approach the future of BP use in MM in the context of other bone-targeted agents, evaluating ongoing clinical trials addressing alternate dosing and schedules of BP administration in MM patients.

A case of acquired Fanconi syndrome induced by zoledronic acid

A 61-year-old woman with metastatic breast cancer was diagnosed as having acquired Fanconi syndrome. In this case, the cause of this syndrome was most likely zoledronic acid (Zometa), which had been infused intravenously at a dose of 4 mg over 15 minutes weekly because of malignancy-associated hypercalcemia. Zoledronic acid is nephrotoxic and may induce severe tubular dysfunction, which can cause development of Fanconi syndrome. Therefore, close monitoring of proximal tubular function is recommended during therapy with zoledronic acid, especially when frequent administration of zoledronic acid is needed.

Prognostic factors and jaw and renal complications among multiple myeloma patients treated with zoledronic acid

Few studies have evaluated prognostic factors among patients with multiple myeloma (MM) since new therapies have become available. Monthly zoledronic acid (ZOL) has been incorporated into many treatment regimens to reduce skeletal-related events (SREs), but outcomes among patients receiving this bisphosphonate have not been well-defined. The aim of this retrospective study was to determine baseline and on-treatment prognostic factors in these patients. Data were collected from the date of diagnosis on 300 consecutive MM patients treated with ZOL. Median duration of ZOL was 18 months (range 1-121 months). The skeletal morbidity rate was 0.116 events per patient year. Five-year overall survival (OS) was 69%. Risk factors for shortened OS included SREs, increased serum creatinine, and International Staging System (ISS) Stage II or III. Thirty-four (11%) patients showed worsening renal function. In 28 of these patients, ZOL was discontinued and restarted in half of these patients following a brief delay. Only 5 of the 34 patients showed worsening of their renal function. Fourteen patients (4.7%) developed osteonecrosis of the jaw (ONJ). All patients with ONJ are in remission or with stable disease except one patient who died of a myocardial infarction while in remission. Only two patients showed some worsening of ONJ despite of ongoing monthly ZOL. Overall, these results suggest that skeletal complications are an important prognostic factor for MM. Although ONJ and renal deterioration may infrequently occur with ZOL, most patients do not experience worsening of these conditions with ongoing treatment with this bisphosphonate.

Development of a novel transdermal patch of alendronate, a nitrogen-containing bisphosphonate, for the treatment of osteoporosis

Bisphosphonates are widely used for the treatment and prevention of bone diseases, including Paget disease, hypercalcemia of malignancy, and postmenopausal osteoporosis. In this study, we developed a novel transdermal patch of alendronate, a nitrogen-containing bisphosphonate, for the treatment of bone diseases. The maximum permeation fluxes of alendronate through rat and human skin after application of this patch were 1.9 and 0.3 µg/cm(2) per hour, respectively. The bioavailability (BA) of alendronate in rats was approximately 8.3% after the application of alendronate patch and approximately 1.7% after oral administration. These results indicated that the transdermal permeation of alendronate using this patch system was sufficient for the treatment of bone diseases. The plasma calcium level was effectively reduced after application of the alendronate patch in 1α-hydroxyvitamin D(3) -induced hypercalcemia model rats. The alendronate patch also effectively suppressed the decrease in bone mass in model rats with osteoporosis. Modest alendronate-induced erythema of rat skin was observed after application of the alendronate patch. Incorporation of butylhydroxytoluene in the alendronate patch almost completely suppressed this alendronate-induced skin damage while maintaining the transdermal permeation and pharmacologic effects of alendronate. These findings indicate that our novel transdermal delivery system for alendronate is a promising approach to improve compliance and quality of life of patients in the treatment of bone diseases.

Denosumab compared with zoledronic acid for the treatment of bone metastases in patients with advanced breast cancer: a randomized, double-blind study

PURPOSE

This randomized study compared denosumab, a fully human monoclonal antibody against receptor activator of nuclear factor κ B (RANK) ligand, with zoledronic acid in delaying or preventing skeletal-related events (SREs) in patients with breast cancer with bone metastases.

PATIENTS AND METHODS

Patients were randomly assigned to receive either subcutaneous denosumab 120 mg and intravenous placebo (n = 1,026) or intravenous zoledronic acid 4 mg adjusted for creatinine clearance and subcutaneous placebo (n = 1,020) every 4 weeks. All patients were strongly recommended to take daily calcium and vitamin D supplements. The primary end point was time to first on-study SRE (defined as pathologic fracture, radiation or surgery to bone, or spinal cord compression).

RESULTS

Denosumab was superior to zoledronic acid in delaying time to first on-study SRE (hazard ratio, 0.82; 95% CI, 0.71 to 0.95; P = .01 superiority) and time to first and subsequent (multiple) on-study SREs (rate ratio, 0.77; 95% CI, 0.66 to 0.89; P = .001). Reduction in bone turnover markers was greater with denosumab. Overall survival, disease progression, and rates of adverse events (AEs) and serious AEs were similar between groups. An excess of renal AEs and acute-phase reactions occurred with zoledronic acid; hypocalcemia occurred more frequently with denosumab. Osteonecrosis of the jaw occurred infrequently (2.0%, denosumab; 1.4%, zoledronic acid; P = .39).

CONCLUSION

Denosumab was superior to zoledronic acid in delaying or preventing SREs in patients with breast cancer metastatic to bone and was generally well tolerated. With the convenience of a subcutaneous injection and no requirement for renal monitoring, denosumab represents a potential treatment option for patients with bone metastases.

Bisphosphonates in Breast Cancer Patients with Bone Metastases

Morbidity and mortality in breast cancer patients are mainly caused by organ failure as a result of distant metastasis. The main target of metastatic disease is the skeleton (next to lungs and liver). Osseous metastases are diagnosed in 75-80% of all women who die due to breast cancer; and the skeleton is the primary metastatic target organ in more than half of these cases. In Germany, the incidence of breast cancer patients with newly diagnosed bone metastases is approximately 11-12,000 cases. Prevalence might amount to 40,000 cases of women with breast cancer and osseous metastases at a median survival time of 3-4 years. The treatment goal at this stage of the disease comprises improvement of quality of life, and reduction of bone pain and typical complications like fractures and hypercalcemia. By consistent use of bisphosphonates these goals can be accomplished. Bisphosphonates improve bone pain significantly and reduce the number of skeletal-related events in women with bone metastases. Bisphosphonates can be administered intravenously or orally, and are well tolerated. Nevertheless, there are side effects and complications including acute phase reaction, nephrotoxicity, osteonecrosis of the jaw, and gastrointestinal disturbances.

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.

Management of osteoporosis in CKD Stages 3 to 5

Osteoporosis and chronic kidney disease (CKD) are both common conditions of older adults and both may be associated with substantial morbidity. However, biochemical and histologic changes that occur with progressive kidney disease require specific interventions, some of which may be concordant with osteoporosis management in the general population, whereas others may be less relevant or perhaps even harmful. In this article, we review the diagnosis of and management strategies for osteoporosis in individuals with CKD, placing these into perspective with the recently published KDIGO (Kidney Disease: Improving Global Outcomes) guidelines for treatment of CKD-mineral and bone disorder (CKD-MBD). Specifically, we highlight osteoporosis treatment recommendations by CKD stage and discuss new avenues for osteoporosis treatment that may be useful in individuals with CKD.

Kidney disease associated with plasma cell dyscrasias

Plasma cell dyscrasias are frequently encountered malignancies often associated with kidney disease through the production of monoclonal immunoglobulin (Ig). Paraproteins can cause a remarkably diverse set of pathologic patterns in the kidney and recent progress has been made in explaining the molecular mechanisms of paraprotein-mediated kidney injury. Other recent advances in the field include the introduction of an assay for free light chains and the use of novel antiplasma cell agents that can reverse renal failure in some cases. The role of stem cell transplantation, plasma exchange, and kidney transplantation in the management of patients with paraprotein-related kidney disease continues to evolve.

Bone health and prostate cancer

Bone metastases are a substantial burden to men with advanced prostate cancer as they often cause pain and can cause fractures and spinal cord compression. Osteoblasts and osteoclasts are both pathologically activated in the setting of prostate cancer bone metastases. As osteoclast activation is associated with disease progression, skeletal complications and death, osteoclast-targeted therapies are a rational approach to disease management. Zoledronic acid is standard of care for castration-resistant prostate cancer with bone metastases as it reduces the risk for skeletal-related events. Additional trials are needed to better define the ideal dose, frequency and duration of zoledronic acid therapy. No bisphosphonate has yet been shown to prevent bone metastases or to benefit men with androgen-sensitive disease. Denosumab is an experimental osteoclast-targeted monoclonal antibody against receptor activator of nuclear factor-kappaB ligand. Two ongoing phase III trials are expected to define its efficacy in preventing bone metastases and disease-related skeletal events in men with prostate cancer. Androgen-deprivation therapy (ADT) for prostate cancer is associated with osteoporosis and fragility fractures. Several bisphosphonates have been shown to improve bone mineral density in men receiving ADT. Two recent phase III trials have shown that denosumab and toremifene reduce the incidence of fragility fractures in these men. The World Health Organization has developed a fracture risk assessment model (FRAX) for the general population to guide the selection of patients who may benefit from pharmacotherapy. In the absence of a prostate cancer-specific algorithm, we advocate the use of FRAX for men receiving ADT.

Is there a role for ibandronate in the treatment of prostate cancer patients with bony metastases?

PURPOSE

Zoledronic acid is widely accepted as the treatment of choice for a number of cancers which metastasise to bone and is the only bisphosphonate licensed for the treatment of prostate cancer. However, drug related nephrotoxicity, although rare, does pose a significant complication when using zoledronic acid. Prostate cancer patients are generally older than 65 years of age and already exhibit some form of impaired renal function. Thus, for prostate cancer patients who are unable to tolerate zoledronic acid there is a need for an alternative bisphosphonate. One possibility could be ibandronate which is also a potent third generation, nitrogen-containing bisphosphonate and is an attractive choice for some patients due to the fact it is available in both intravenous and oral preparations.

METHODS

This article reviews the current published literature regarding the use of ibandronate in the treatment of metastatic prostate cancer.

RESULTS

Preliminary data emerging from small Phase II studies suggests ibandronate may provide a therapeutic alternative for the treatment of metastatic prostate cancer when zoledronic acid is deemed unsuitable.

CONCLUSION

Further in vivo research with ibandronate in prostate cancer is urgently needed in order to elucidate whether this bisphosphonate may play a role in the treatment and palliative management of metastatic prostate cancer.

Current options for the treatment of Paget's disease of the bone

Paget’s disease of bone (PDB) is a chronic bone remodelling disorder characterized by increased osteoclast-mediated bone resorption, with subsequent compensatory increases in new bone formation, resulting in a disorganized mosaic of woven and lamellar bone at affected skeletal sites. This disease is most often asymptomatic but can be associated with bone pain or deformity, fractures, secondary arthritis, neurological complications, deafness, contributing to substantial morbidity and reduced quality of life. Neoplastic degeneration of pagetic bone is a relatively rare event, occurring with an incidence of less than 1%, but has a grave prognosis. Specific therapy for PDB is aimed at decreasing the abnormal bone turnover and bisphosphonates are currently considered the treatment of choice. These treatments are associated with a reduction in plasma alkaline phosphatase (ALP) activity and an improvement in radiological and scintigraphic appearance and with a reduction in bone pain and bone deformity, Recently, the availability of newer, more potent nitrogen-containing bisphosphonates has improved treatment outcomes, allowing a more effective and convenient management of this debilitating disorder.

The Effect of Alendronate, Risedronate, and Raloxifene on Renal Functions, Based on the Cockcroft and Gault Method, in Postmenopausal Women

BACKGROUND

Oral alendronate, risedronate, and raloxifene are effective treatment options in the management of postmenopausal osteoporosis. There is little previously reported about the renal safety profiles of these three agents in osteoporosis. We aimed to assess the risk of renal toxicity associated with oral alendronate, risedronate, and raloxifene in the treatment of osteoporosis, prospectively.

METHODS

One hundred and twenty-seven patients with osteoporosis and osteopenia according to lumbar or femoral-neck bone mineral density t score were enrolled in the study. The patients were randomized to alendronate 70 mg once weekly (n = 47), risedronate 35 mg once weekly (n = 44), or raloxifene 60 mg per day (n = 36) for one year. Preliminary screening included medical history, physical examination, lumbar and femoral bone mineral densitometry measurement, and blood biochemical tests, including renal function tests. The biochemical markers were then assessed at the end of 12 months.

RESULTS

There was no significant difference between basal and final renal function parameters of each group. Also these parameters did not differ between the three groups after 12 months of treatment period.

CONCLUSIONS

These results demonstrate that alendronate, risedronate, and raloxifene are all safe drugs for renal functions in the treatment of osteoporosis.

High incidence of hypocalcemia and serum creatinine increase in patients with bone metastases treated with zoledronic acid

BACKGROUND

Zoledronic acid belongs to the new generation of bisphosphonates with demonstrated clinical benefit for the treatment of bone metastases from different kinds of neoplasms. Hypocalcemia and serum creatinine elevation are expected adverse events during this therapy. The monitoring of serum calcium and creatinine is therefore recommended. The primary aim of this study was to establish the actual incidence of hypocalcemia and serum creatinine elevation during treatment with zoledronic acid. Skeletal-related events and side effects were also assessed.

METHODS

Serum creatinine and calcium levels were evaluated in 240 consecutive patients (83 males, 157 females; mean age, 62 years) with metastatic bone lesions from different solid tumors treated with zoledronic acid.

RESULTS

Overall, 93 of 240 patients (38.8%) developed hypocalcemia, which was grade (G)1 in 45 patients (48.4%), G2 in 37 patients (39.8%), G3 in 10 patients (10.8%), and G4 in one patient (1.1%). The median time to occurrence of hypocalcemia (any grade) was 2.3 months after the beginning of the treatment (range, 0-34.9 months). Increased serum creatinine was observed in 33 of 240 patients (13.7%), of whom 19 had G1 (57.6%), 11 had G2 (33.3%), and three had G3 (9.1%). The median time to serum creatinine increase (for any grade) was 4.7 months (range, 0-29.2 months).

CONCLUSIONS

Our analysis shows a high incidence of hypocalcemia and increased serum creatinine level during treatment with zoledronic acid. These results strongly support the need for accurate monitoring of plasma calcium and creatinine levels.

Bisphosphonate-associated osteomyelitis of the jaw: guidelines for practicing clinicians

OBJECTIVE

To evaluate the literature and discuss the risk factors, mechanisms, pathophysiologic aspects, and recommended management of bisphosphonate-associated osteomyelitis of the jaw (BAOMJ).

METHODS

More than 350 published articles, case reports mentioning BAOMJ, and independent histology slides from BAOMJ lesions were reviewed critically. The most pertinent publications are cited and discussed.

RESULTS

The incidence of BAOMJ increases after extraction of teeth, dentoalveolar surgical procedures, or recent oral trauma leading to exposed maxillary or mandibular bone. Contributory factors include poor oral hygiene, oral infections, periodontal disease; recent or ongoing corticosteroid administration or chemotherapy; compromised immune status; diabetes or vascular insufficiency; old age; chronic diseases; and malignancies. On average, 1 of every 100,000 patients treated with bisphosphonates orally for osteoporosis or Paget disease of bone may develop BAOMJ-like lesions. Patients with cancer often receive bisphosphonate doses 10 times or higher, and also more frequently, than those used in patients with osteoporosis or Paget disease of bone. Therefore, greater frequency of administration of bisphosphonates, higher dosages, and prolonged use (that is, for more than 2 years) are likely to be factors triggering BAOMJ.

CONCLUSION

The association of bisphosphonate therapy with BAOMJ is rare in noncancer patients and is likely to be a class effect that may occur with use of any bisphosphonate. Whether patients with cancer require such a high frequency of intravenously administered bisphosphonates needs to be investigated. Following established guidelines can decrease the risks of BAOMJ in vulnerable patients. Rather than necrotic bone, current evidence supports an infectious and perhaps immunologic underlying cause for BAOMJ. The estimated incidence of BAOMJ among noncancer patients receiving bisphosphonates is about 0.001%, whereas among patients with cancer receiving intravenous bisphosphonate therapy the incidence is between 0.5% and 4%, depending on the dose, frequency, and duration of therapy (on average, approximately 2%). Nevertheless, the benefits of bisphosphonates far outweigh the risks.

Proteinuria and proximal tubule lesions induced by an anti-integrin monoclonal antibody treatment: case report

Blocking integrin binding to fibronectin by a monoclonal antibody directed to integrin receptors induces apoptosis of proliferating endothelial cells. We report a case of grade 2 proteinuria, occurred fifteen days after the first administration of an anti-integrin monoclonal antibody associated to standard doses of carboplatin/paclitaxel and to a single dose of zoledronic acid in a patient treated in first line setting for a metastatic non small cell lung cancer. Kidney biopsy revealed a tubular damage probably associated to minimal change glomerulonephritis. Even if this patient did not receive any further dose of zoledronic acid, proteinuria reoccurred, although at a lower level when the investigational drug was reintroduced at the same dose. Renal function remained normal. The patient received two further cycles with lower doses, without recurrence of proteinuria. These findings suggest that this type of integrin antibody may induce transient urinary excretion of protein in a dose dependent manner without adversely affecting renal function.

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

Reversal of hypercalcemic acute kidney injury by treatment with intravenous bisphosphonates

We present the details of three children with hypercalcemia-induced acute kidney injury (AKI). After traditional therapy with fluids, loop diuretics, steroids and calcitonin had failed to correct the hypercalcemia, they were given treatment with low doses of intravenous (i.v.) pamidronate, which resulted in normalization of serum calcium and kidney function. In one child Doppler renal ultrasound revealed dampened arterial blood flow, which resolved with normalization of serum calcium. On the basis of cumulative data and our experience, we suggest that i.v. application of bisphosphonates be moved from the second to the first line of treatment of hypercalcemic AKI.

Emerging therapy-related kidney disease

CONTEXT

Many new therapies have emerged within the last 5 to 10 years to treat a variety of conditions. Several of these have direct or indirect renal toxicities that may go undiagnosed without careful attention of the pathologist to a patient's clinical history, particularly the addition of new medications or treatments.

OBJECTIVE

To discuss patterns of renal injury resulting from medications or therapeutic regimens that have been introduced within the last 10 years. Recognition of these patterns may allow the pathologist to alert the attending clinician to a possible drug-induced renal injury and prevent further deterioration of renal function and possible chronic kidney disease.

DATA SOURCES

A review of recent literature and unpublished observations of case-derived material.

CONCLUSIONS

A number of newer therapies have emerged as agents of renal toxicity, producing a variety of pathologic changes in the kidney. The outcome can be acute or chronic glomerular, tubular, interstitial, and/or vascular injury. Some drugs will result in irreversible changes and end-stage renal disease, whereas many of the alterations can be reversed with removal of the offending agent, avoiding potential long-term kidney injury.

Effect of bisphosphonates on vascular calcification and bone metabolism in experimental renal failure

Although it is known that bisphosphonates prevent medial vascular calcification in vivo, their mechanism of action remains unknown and, in particular, whether they act directly on the blood vessels or indirectly through inhibition of bone resorption. To determine this, we studied the effects of two bisphosphonates on calcification of rat aortas in vitro and on in vivo aortic calcification and bone metabolism in rats with renal failure. We produced vascular calcification in rats with adenine-induced renal failure fed a high-phosphate diet. Daily treatment with either etidronate or pamidronate prevented aortic calcification, with the latter being 100-fold more potent. Both aortic calcification and bone formation were reduced in parallel; however, bone resorption was not significantly affected. In all uremic rats, aortic calcium content correlated with bone formation but not with bone resorption. Bisphosphonates also inhibited calcification of rat aortas in culture and arrested further calcification of precalcified vessels but did not reverse their calcification. Expression of osteogenic factors or calcification inhibitors was not altered by etidronate in vitro. Hence, these studies show that bisphosphonates can directly inhibit uremic vascular calcification independent of bone resorption. The correlation between inhibition of aortic calcification and bone mineralization is consistent with a common mechanism such as the prevention of hydroxyapatite formation and suggests that bisphosphonates may not be able to prevent vascular calcification without inhibiting bone formation in uremic rats.

The proteasome inhibitor, bortezomib suppresses primary myeloma and stimulates bone formation in myelomatous and nonmyelomatous bones in vivo

Multiple myeloma (MM), a hematologic malignancy of terminally differentiated plasma cells is closely associated with induction of osteolytic bone disease, induced by stimulation of osteoclastogenesis and suppression of osteoblastogenesis. The ubiquitin-proteasome pathway regulates differentiation of bone cells and MM cell growth. The proteasome inhibitor, bortezomib, is a clinical potent antimyeloma agent. The main goal of this study was to investigate the effect of bortezomib on myeloma-induced bone resorption and tumor growth in SCID-rab mice engrafted with MM cells from 16 patients. Antimyeloma response of bortezomib, which was evident in >50% of 16 experiments and resembled clinical response, was associated with significant increased bone mineral density (BMD) and osteoblast numbers, and reduced osteoclast numbers in myelomatous bones. This bone anabolic effect, which was also visualized on X-ray radiographs and confirmed by static and dynamic histomorphometric analyses, was unique to bortezomib and was not observed in hosts responding to melphalan, a chemotherapeutic drug widely used to treat MM. Bortezomib also increased BMD and osteoblasts number and reduced osteoclasts number in nonmyelomatous implanted bones. In vitro bortezomib directly suppressed human osteoclast formation and promoted maturation of osteoblasts. We conclude that bortezomib promotes bone formation in myelomatous and nonmyelomatous bones by simultaneously inhibiting osteoclastogenesis and stimulating osteoblastogenesis. As clinical and experimental studies indicate that bone disease is both a consequence and necessity of MM progression our results suggest and that bortezomib's effects on bone remodeling contribute to the antimyeloma efficacy of this drug.

Poor Survival Outcome With Moderate and Severe Hypercalcemia in Gynecologic Malignancy Patients

Objective:

Determine the incidence of hypercalcemia in gynecologic malignancy patients and their survival outcome.

Design:

Single-institution retrospective clinical study.

Patients and Methods:

We used Fisher exact test, Kaplan-Meier survival curves, and Cox proportional hazards model to analyze demographic and clinical data from gynecologic malignancy patients with hypercalcemia who had been treated at The University of Texas M. D. Anderson Cancer Center from September 1997 to August 2006.

Results:

Of the 5260 gynecologic malignancy patients, 268 had hypercalcemia (5%). Of the 268, 12 were excluded because of hyperparathyroidism or coexisting malignancies; thus, 256 patients were included in the study. Most patients (82%) had mild hypercalcemia. Severity of hypercalcemia was associated with disease stage (P = 0.0019), use of hypercalcemia treatment (P < 0.0001), and survival duration (P < 0.0001). The median survival duration of patients who had not been treated for hypercalcemia was 432 days compared with 106 days in patients who had been treated. The shorter survival duration of treated patients seems to result from their disease status and hypercalcemia severity rather than whether they were treated for hypercalcemia.

Conclusions:

Moderate and severe hypercalcemia is associated with poorer survival duration in gynecologic malignancy patients. Early detection and treatment of hypercalcemia in these patients may prolong survival. To our knowledge, this is the first study of hypercalcemia in patients with general gynecologic malignancy.

Randomized, active-controlled study of once-weekly alendronate 280 mg high dose oral buffered solution for treatment of Paget's disease

Daily oral tablet bisphosphonate therapy for Paget's disease of bone may cause serious upper gastrointestinal adverse events. A once-weekly alendronate 280 mg oral buffered solution was compared with an alendronate 40 mg/day tablet. While both were similarly effective, the tablet appeared to be better tolerated in this study.

INTRODUCTION

Although daily doses of oral bisphosphonates are a generally safe and effective treatment for Paget's disease of bone (PDB), some patients may experience upper gastrointestinal adverse events (UGI AEs) or find the dosing requirements inconvenient and become noncompliant. A once-weekly (OW) oral dose of bisphosphonate in buffered solution (OBS) may be as effective, better tolerated, and more convenient.

METHODS

Sixty-three patients were randomized to either alendronate (ALN) 280 mg OW OBS (n = 42) or an ALN 40 mg/day tablet (n = 21) during a 6-month, randomized, double-blind, active-controlled trial. The primary endpoint was the mean percent decrease in total serum alkaline phosphatase (total ALP) from baseline at 6 months.

RESULTS

There were no significant differences in total ALP between groups during the 6-month period. There was a higher incidence of clinical AEs in the ALN 280 mg OW OBS (79%) vs. the ALN 40 mg/day tablet group (67%), including drug related AEs (48% and 10%, respectively), which led to study discontinuation (19.0% and 10%, respectively).

CONCLUSIONS

Although ALN 280 mg OW OBS was similarly effective as ALN 40 mg/day in reducing total ALP in patients with PDB, the ALN 40 mg/day tablet appears to be better tolerated than ALN 280 mg OW OBS.

Risk of renal impairment after treatment with ibandronate versus zoledronic acid: a retrospective medical records review

PURPOSE

This retrospective study compared renal impairment rates in breast cancer, multiple myeloma, prostate cancer and non-small cell lung cancer patients treated with ibandronate or zoledronic acid.

STUDY DESIGN

Medical records in two German oncology clinics from May 2001 to March 2006 were retrospectively reviewed. Creatinine measurements were analyzed from baseline (before bisphosphonate treatment) to last available measurement for each patient. The Cox proportional hazards model and the Andersen-Gill extension of the Cox model for multiple events analysis were used for multivariate analysis, which controlled for age, clinic site, primary cancer type, baseline SCr or GFR value, prior bisphosphonate use, concomitant use of drugs associated with acute renal failure, and renal-related comorbidities.

RESULTS

Of 333 patients, 109 received ibandronate and 256 received zoledronic acid (32 patients had both drugs). Compared with ibandronate, the zoledronic acid group had a significantly better baseline renal function and fewer patients had a history of renal disease. Zoledronic acid treatment increased the relative risk (RR) and the incidence rate (IR) of renal impairment by approximately 1.5-fold in all assessed patients (all tumors) compared with ibandronate. Multivariate analysis found significantly higher hazards ratios for zoledronic acid over ibandronate (two to sixfold), after adjusting for differences in characteristics between the two treatment groups.

CONCLUSIONS

In this retrospective review, patients were significantly more likely to experience renal impairment with zoledronic acid than with ibandronate.

Nephrotoxicity as a cause of acute kidney injury in children

Many different drugs and agents may cause nephrotoxic acute kidney injury (AKI) in children. Predisposing factors such as age, pharmacogenetics, underlying disease, the dosage of the toxin, and concomitant medication determine and influence the severity of nephrotoxic insult. In childhood AKI, incidence, prevalence, and etiology are not well defined. Pediatric retrospective studies have reported incidences of AKI in pediatric intensive care units (PICU) of between 8% and 30%. It is widely recognized that neonates have higher rates of AKI, especially following cardiac surgery, severe asphyxia, or premature birth. The only two prospective studies in children found incidence rates of 4.5% and 2.5% of AKI in children admitted to PICU, respectively. Nephrotoxic drugs account for about 16% of all AKIs most commonly associated with AKI in older children and adolescents. Nonsteroidal anti-inflammatory drugs (NSAIDs), antibiotics, amphotericin B, antiviral agents, angiotensin-converting enzyme (ACE) inhibitors, calcineurin inhibitors, radiocontrast media, and cytostatics are the most important drugs to indicate AKI as significant risk factor in children. Direct pathophysiological mechanisms of nephrotoxicity include constriction of intrarenal vessels, acute tubular necrosis, acute interstitial nephritis, and-more infrequently-tubular obstruction. Furthermore, AKI may also be caused indirectly by rhabdomyolysis. Frequent therapeutic measures consist of avoiding dehydration and concomitant nephrotoxic medication, especially in children with preexisting impaired renal function.

Bisphosphonates in chronic kidney disease; balancing potential benefits and adverse effects on bone and soft tissue

Cardiovascular disease is highly prevalent in chronic kidney disease (CKD) and is often associated with increased vascular stiffness and calcification. Recent studies have suggested a complex interaction between vascular calcification and abnormalities of bone and mineral metabolism, with an inverse relationship between arterial calcification and bone mineral density (BMD). Although osteoporosis is recognized and treated in CKD 1 to 3, the interpretation of BMD levels in the osteoporotic range is controversial in CKD 4, 5, and 5D when renal osteodystrophy is generally present. In addition, there is a paucity of data for patients with CKD mineral and bone disorder (MBD), because studies using bisphosphonates in postmenopausal and glucocorticoid-induced osteoporosis have generally excluded patients with significant CKD. For these patients, treatment of low BMD using standard therapies for osteoporosis is not without potential for harm due to the possibility of worsening low bone turnover, osteomalacia, mixed uraemic osteodystrophy, and of exacerbated hyperparathyroidism; and bisphosphonates should only be used selectively and with caution. Some experimental and clinical studies have also suggested that bisphosphonates may reduce progression of extra-osseous calcification and inhibit the development of atherosclerosis. The authors review the potential benefits and risks associated with bisphosphonate use for bone protection in CKD, and assess their effect on vascular calcification and atherosclerosis.

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.