Relapse of minimal change nephrotic syndrome after intravitreal bevacizumab

Effect of Intravitreal Anti-Endothelial Growth Factor Agents on Renal Function in Patients With Diabetes Mellitus

Introduction

Intravitreal administration of vascular endothelial growth factor inhibitors (anti-VEGF) is the treatment of choice in retinal pathology associated with type 2 diabetes mellitus (DM2). We aimed to analyze the effect of intravitreal anti-VEGF administration on renal function in patients with DM2.

Methods

This is a single-center retrospective and observational study of patients with DM2 with and without chronic kidney disease (CKD). We analyzed the evolution of renal function after anti-VEGF onset, compared with a control group.

Results

We included 45 patients (55.6% male) who received anti-VEGF therapy. Mean age was 74.4±11.5 (50-91) years. These were compared with 45 patients with similar characteristics. After 12 months, 76.3% had CKD with a mean reduction in estimated glomerular filtration rate (eGFR) of 19.4%. Nine patients (20%) had a >25% reduction in eGFR, and 3 patients (6.7%) had a >50% reduction in GFR. At 24 months, 80% of patients had CKD with a mean eGFR decrease of 28%. The mean eGFR slope of patients who had received anti-VEGF treatment was 10 ml/min/year compared to 1.5 ml/min/year in the control group (P < 0.05). After the first administration, 5 patients (17.2%) in the CKD group required renal replacement therapy during follow-up (mean time 22±12 months). Main risk factors for need of dialysis were age, presence of previous CKD, and baseline proteinuria.

Conclusion

Intravitreal anti-VEGF administration is a risk factor for CKD and rapid progression to end-stage kidney disease in patients with previous CKD. Knowing these drugs' implications is crucial to avoid CKD progression and opportunely limit their use in certain patients.

Membranoproliferative glomerulonephritis after intravitreal vascular growth factor inhibitor injections: A case report and review of the literature

Systemic administration of agents that inhibit vascular endothelial growth factor (VEGF) and therefore vascular proliferation is often used to treat various cancers. However, these agents are associated with a number of side effects, including proteinuria and renal injury. Intravitreal injection of anti-VEGF agents has become the cornerstone of macular disease treatment. Since these agents cross the blood-retina barrier and enter the circulation, systemic side effects have been reported. We report the novel case of a 57-year-old patient who presented with macular oedema secondary to central retinal vein occlusion, underwent three monthly loading-dose injections with the anti-VEGF agent ranibizumab, and 2 weeks after the second injection presented with biopsy-verified membranoproliferative glomerulonephritis. Twelve weeks after presenting with renal failure and 10 weeks after his last anti-VEGF injection, the patient demonstrated spontaneous recovery of his kidney function. The patient had a history that promoted renal fragility, including hypertension, liver transplantation 6 years earlier for alcohol-related cirrhosis and new-onset diabetes mellitus after transplant. Our literature review and case suggest that although adverse renal events after intravitreal anti-VEGF injections are very rare, ophthalmologists and nephrologists should be aware of this risk.

Intravitreal vascular endothelial growth factor inhibitors did not increase the risk of end-stage renal disease in patients with biopsy-proven diabetic kidney disease based on matched study

Purpose: This study aimed to investigate the effects of intravitreal (IVT) VEGFi on long-term renal outcomes in patients with biopsy-proven diabetic kidney disease (DKD). Patients and methods: Patients prescribed IVT VEGFi (VEGFi group) were enrolled from a retrospective cohort with biopsy-proven DKD, and those not prescribed VEGFi (non-VEGFi group) were enrolled by 1:3 propensity score matching, adjusted for clinical and pathological baseline indicators. The primary endpoint is defined as end-stage renal disease (ESRD) and the secondary endpoint is defined as all-cause mortality. Results: Compared with patients in non-VEGFi group, patients with VEGFi had a higher proportion of diabetic retinopathy (DR) (50.9% vs 100%, p < 0.001) before matching. Standardized mean difference (SMD) of age, DR, duration of diabetes, the proportion of hypertension, eGFR, initial proteinuria, serum albumin, hemoglobin, the proportion of RAAS inhibitor and interstitial fibrosis and tubular atrophy (IFTA) were >10%. After matching, there was no significant difference in clinical pathology between the two groups. Except for the proportion of hypertension, the SMD of other indicators was <10%. Endpoints such as ESRD (Log-Rank p = 0.772) and all-cause mortality (Log-Rank p = 0.834) were not significantly different between the two groups. Conclusion: Our data suggested that IVT VEGFi did not increase the incidence of ESRD and all-cause mortality in patients with DKD.

Intravitreal vascular endothelial growth factors hypertension, proteinuria, and renal injury: a concise review

PURPOSE OF REVIEW

Nearly 20 years ago, vascular endothelial growth factor (VEGF)inhibitors (VEGFi) were adapted from systemic use from antiangiogenesis roles to intravitreal uses. Initially bevacizumab a murine immunoglobulin was injected 'off label' as a treatment for diabetic macular edema and age-related macular degeneration. Throughout the following decade aflibercept and finally ranibizumab were adapted and obtained Food and Drug Administration approval for intravitreal use. Initially systemic absorption was thought to be quite low after intravitreal injections and was quoted as being 200-fold lower than levels postulated to induce significant VEGF inhibition. Pharmacodynamic studies obtained in 2014 and again in 2017 revealed significant systemic absorption and detectable VEGF inhibition, this has since been confirmed in multiple subsequent studies.

RECENT FINDINGS

A few case reports of renal dysfunction and glomerular disease related to VEGFi were initially identified. Mixed findings on effects on blood pressure were noted in studies. More recently, 32 cases of de-novo glomerular disease and/or proteinuria exacerbation were identified. New studies have corroborated increased blood pressure, proteinuria exacerbation in patients with pre-existing nephrotic syndrome, and systemic VEGF depletion. Further, the most common lesion of systemic VEGFi nephrotoxicity, thrombotic microangiopathy, has recently been reported by our group.

SUMMARY

We will review the pharmacokinetic, translational, and epidemiological data that year upon year establish the finite-yet real risk of intravitreal VEGFi.

Review of intravitreal VEGF inhibitor toxicity and report of collapsing FSGS with TMA in a patient with age-related macular degeneration

Intravitreal vascular endothelial growth factor (VEGF) receptor blockade is used for a variety of retinal pathologies. These include age-related macular degeneration (AMD), diabetic macular edema (DME) and central retinal vein obstruction. Reports of absorption of intravitreal agents into systemic circulation have increased in number and confirmation of depletion of VEGF has been confirmed. Increasingly there are studies and case reports showing worsening hypertension, proteinuria, renal dysfunction and glomerular disease. The pathognomonic findings of systemic VEGF blockade, thrombotic microangiopathies (TMAs), are also being increasingly reported. One lesion that occurs in conjunction with TMAs that has been described is collapsing focal segmental glomerulosclerosis (cFSGS). cFSGS has been postulated to occur due to TMA-induced chronic glomerular hypoxia. In this updated review we discuss the mechanistic, pharmacological, epidemiological and clinical evidence of intravitreal VEGF toxicity. We review cases of biopsy-proven toxicity presented by our group and other investigators. We also present the third reported case of cFSGS in the setting of intravitreal VEGF blockade with a chronic TMA component that was crucially found on biopsy. This patient is a 74-year-old nondiabetic male receiving aflibercept for AMD. Of the two prior cases of cFSGS in the setting of VEGF blockade, one had AMD and the other had DME. This case solidifies the finding of cFSGS and its association with chronic TMA as a lesion that may be frequently encountered in patients receiving intravitreal VEGF inhibitors.

Worsening proteinuria and renal function after intravitreal vascular endothelial growth factor blockade for diabetic proliferative retinopathy

Systemic vascular endothelial growth factor (VEGF) inhibitions can induce worsening hypertension, proteinuria and glomerular diseases of various types. These agents can also be used to treat ophthalmic diseases like proliferative diabetic retinopathy, diabetic macular edema, central retinal vein occlusion and age-related macular degeneration. Recently, pharmacokinetic studies confirmed that these agents are absorbed at levels that result in biologically significant suppression of intravascular VEGF levels. There have now been 23 other cases published that describe renal sequela of intravitreal VEGF blockade, and they unsurprisingly mirror known systemic toxicities of VEGF inhibitors. We present three cases where stable levels of proteinuria and chronic kidney disease worsened after initiation of these agents. Two of our three patients were biopsied. The first patient's biopsy showed diabetic nephropathy and focal and segmental glomerulosclerosis (FSGS) with collapsing features and acute interstitial nephritis (AIN). The second patient's biopsy showed AIN in a background of diabetic glomerulosclerosis. This is the second patient seen by our group, whose biopsy revealed segmental glomerulosclerosis with collapsing features in the setting of intravitreal VEGF blockade. Though FSGS with collapsing features and AIN are not the typical lesions seen with systemic VEGF blockade, they have been reported as rare case reports previously. In addition to reviewing known elements of intravitreal VEGF toxicity, the cases presented encompass renal pathology data supporting that intravitreal VEGF blockade can result in deleterious systemic and renal pathological disorders.

Nephrotic Syndrome with Focal Segmental Glomerulosclerosis Induced by Intravitreal Injections of Vascular Endothelial Growth Factor Inhibitor

An 83-year-old woman with a 1-year history of scheduled intravitreal injection of vascular endothelial growth factor (VEGF) inhibitor (aflibercept) was diagnosed with nephrotic syndrome due to focal segmental glomerulosclerosis with histopathological findings of segmental infiltration of foam cells in the glomerular capillaries. Her nephrotic syndrome improved immediately following the termination of aflibercept intravitreal injection without steroid therapy. Although widely used to treat ophthalmic diseases, we should keep in mind that even intravitreal injection of VEGF inhibitor, as opposed to systemic administration, can cause kidney injury.

Thrombotic Microangiopathy and Acute Kidney Injury Induced After Intravitreal Injection of Vascular Endothelial Growth Factor Inhibitors VEGF Blockade-Related TMA After Intravitreal Use

Vascular endothelial growth factor (VEGF) inhibition can cause worsening hypertension, proteinuria, chronic kidney injury, and glomerular disease. Thrombotic microangiopathy (TMA) and other nephrotic disorders have been reported with systemic VEGF blockade. These same agents are given intravitreally for age-related macular degeneration (AMD) and diabetic retinopathy (DR), albeit at lower doses than those given for systemic indications. Systemic absorption of anti-VEGF agents when given intravitreally has been shown consistently along with evidence of significant intravascular VEGF suppression. While worsening hypertension has only been seen in some large-scale studies, case reports show worsening proteinuria and diverse glomerular diseases. These include TMA-associated lesions like focal and segmental glomerulosclerosis with collapsing features (cFSGS). In this paper, we report three cases of TMA likely associated with the use of intravitreal anti-VEGF therapy. These patients developed the signature lesion of VEGF blockade in a 6 to 11 month time frame after starting intravitreal VEGF inhibitors. The literature is reviewed showing similar cases. Intravitreal VEGF blockade may cause these adverse events in a hitherto unidentified subgroup of patients. Well-controlled prospective observational trials are needed to determine the event rate and identify which subgroups of patients are at increased risk. A registry for patients who develop worsening hypertension, proteinuria exacerbation, and glomerular diseases from intravitreal VEGF blockade is proposed.

Nephrotoxicity induced by intravitreal vascular endothelial growth factor inhibitors: emerging evidence

Vascular endothelial growth factor (VEGF) inhibitors have emerged as powerful tools to treat malignant neoplasms and ocular diseases by virtue of their ability to inhibit angiogenesis. Recent data indicate that intravitreal injections of VEGF inhibitors can lead to significant systemic absorption as well as a measurable reduction of plasma VEGF activity. There is increasing evidence showing that vitreal absorption of these drugs is associated with cases of accelerated hypertension, worsening proteinuria, glomerular disease, thrombotic microangiopathy, and possible chronic renal function decline. In this review, the 3 most commonly used anti-VEGF agents-bevacizumab, ranibizumab, and aflibercept-are discussed, highlighting their intravitreal absorption and associated effects on the kidney as a target organ system. We provide clinical suggestions for clinicians to both better manage patients receiving anti-VEGF agents intravitreally and detect any putative systemic renal effects of these agents. While acknowledging the risks of aberrant retinal angiogenesis, it is important for clinicians to be aware of the potential for adverse renal risks with use of these agents.

Three patients with injection of intravitreal vascular endothelial growth factor inhibitors and subsequent exacerbation of chronic proteinuria and hypertension

Vascular endothelial growth factor (VEGF) receptor inhibition is a commonly used tool to prevent vascular proliferation in tumors and retinal diseases. The antiangiogenic effects of these drugs have made them potent adjunct therapies when given systemically for malignancies. They are also useful tools to ameliorate diminishing eyesight in retinopathy. Hypertension and proteinuria have been observed in systemic VEGF inhibitor therapy, with rarer presentations involving nephrotic-range proteinuria due to glomerulopathies. Pharmacokinetic studies have shown detectable blood levels of anti-VEGF inhibitors up to 30 days postintravitreal injection. Animal studies have also demonstrated binding of VEGF inhibitors in simian glomeruli 1 week after a single intravitreal injection. We report three patients who received intravitreal bevacizumab and/or aflibercept with worsening hypertension, proteinuria and renal injury. Data regarding emerging evidence of VEGF inhibitor nephrotoxicity after intravitreal injections are also presented. The clinical data and the existing literature are reviewed to support the hypothesis that intravitreal anti-VEGF agents may be unrecognized nephrotoxins. These agents are given to vulnerable patients with diabetes, hypertension and preexisting nephropathy and proteinuria. This case series is reported to spur further study of the systemic effects of intravitreal VEGF inhibitors.

Self-limited membranous nephropathy after intravitreal bevacizumab therapy for age-related macular degeneration

Background:

Monoclonal antibodies targeting vascular endothelial growth factor (VEGF), such as bevacizumab, are administered intravitreally for the treatment of wet or exudative age-related macular degeneration (ARMD). Systemic use of bevacizumab has been linked to a wide range of renal adverse effects including proteinuria and hypertension.

Case Presentation:

We present the case of a 77-year-old Caucasian male with a past medical history of hypertension, vitamin D deficiency and paroxysmal atrial fibrillation who presented to primary care clinic with a 2-week history of bilateral lower extremity edema, 2 months after completing four monthly intravitreal injections of bevacizumab for ARMD. Examination was remarkable for blood pressure of 187/91 mm Hg and severe bilateral lower extremity edema. Work up revealed unremarkable complete blood count (CBC), comprehensive metabolic panel (CMP), lipid panel, and echocardiography, except for 491 mg/dL albuminuria. Metoprolol and furosemide were added to hydrochlorothiazide and lisinopril. Work up by nephrology consult team five months later was notable for a urinalysis revealing 3 red blood cells/high power field (RBC/HPF), 24-hour urine protein of 8.6 g, and serum creatinine of 1.2 mg/dL. Viral hepatitis panel, total complement activity (CH50), C3, C4, anti-nuclear antibody (ANA), anti-neutrophil cytoplasmic antibody (ANCA), serum and urine protein electrophoresis were all unremarkable. Renal biopsy was consistent with membranous nephropathy. Age-appropriate cancer screening was negative. Random urine protein-to-creatinine ratio declined to 2 g/g and then to 0.56 g/g at 7 and 10 months follow up, respectively. Serum blood urea nitrogen (BUN) and creatinine remained normal throughout the course of illness and patient did not require any immunosuppressive treatment.

Conclusions:

The wide range of nephrotoxicity after systemic bevacizumab has been well documented. Our case describes a self-limited biopsy-proven membranous nephropathy after intravitreal bevacizumab injections.

Minimal change disease onset observed after bevacizumab administration

This is a report of a patient with minimal change disease (MCD) onset after bevacizumab administration. A 72-year-old man with inoperable Grade 3 astrocytoma was treated with a combination of temozolomide and the vascular endothelial growth factor monoclonal antibody bevacizumab. After two biweekly treatments, he developed nephrotic syndrome. Despite cessation of bevacizumab, his renal function deteriorated and a renal biopsy disclosed MCD. Thereafter, he was started on high-dose oral prednisone and renal function immediately improved. Within weeks, the nephrotic syndrome resolved. Although rare, biologic agents can cause various glomerulopathies that can have important therapeutic implications. MCD should be considered in patients who develop nephrotic syndrome while exposed to antiangiogenic agents.

Effects of a single intravitreal injection of aflibercept and ranibizumab on glomeruli of monkeys

PURPOSE

It is known that endothelial cells in the kidney are also strongly VEGF-dependent. Whether intravitreal drugs can be detected within the glomeruli or affect VEGF in glomerular podocytes is not known. Therefore, the aim of this pilot study was to investigate the effects of a single intravitreal injection of aflibercept and ranibizumab on glomeruli of monkeys.

METHODS

The kidneys of eight cynomolgus monkeys, which were intravitreally injected either with 2 mg of aflibercept or with 0.5 mg of ranibizumab, were investigated one and seven days after injection. Two animals served as controls. The distribution of aflibercept, ranibizumab and VEGF was evaluated using anti-Fc- or anti-F(ab)-fragment and anti-VEGF antibodies respectively. The ratio of stained area/nuclei was calculated using a semi-quantitative computer assisted method. Glomerular endothelial cell fenestration was quantified in electron microscopy using a systematic uniform random sampling protocol and estimating the ratio of fenestrae per µm.

RESULTS

Compared to the controls, the anti-VEGF stained area/nuclei ratio of the ranibizumab-treated animals showed no significant changes whereas the stained areas of the aflibercept-treated monkeys showed a significant decrease post-treatment. Immune reactivity (IR) against aflibercept or ranibizumab was detected in aflibercept- or ranibizumab treated animals respectively. The number of fenestrations of the glomerular endothelial cells has shown no significant differences except one day after aflibercept injection in which the number was increased.

CONCLUSION

Surprisingly, both drugs could be detected within the capillaries of the glomeruli. After a single intravitreal injection of aflibercept, VEGF IR in the podocytes was significantly reduced compared to controls. Ranibizumab injection had no significant effect on the glomeruli's VEGF level. Whether this is caused by aflibercept's higher affinity to VEGF or because it is used in a higher stoichiometric concentration compared to ranibizumab remains to be investigated.