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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.

Pembrolizumab is an immune checkpoint inhibitor that targets the programmed cell death protein 1 (PD-1) antigen and induces an immune response against tumor tissues. It has been successful in inducing remission in patients with severe metastatic disease, often refractory to other chemotherapeutic agents. The risk of injury of other organ systems has been noted with reported cases of glomerular disease and endocrine disease. In addition, hypophysitis as well as dermatological and gastroenterological side effects have been reported. Renal injury with immune checkpoint inhibitors like nivolumab and pembrolizumab is usually mediated via interstitial nephritis, though glomerular disease presentations like anti-neutrophil cytoplasmic antibody-associated vasculitis, immune complex disease, and thrombotic microangiopathy have also been reported. We report a 70-year-old Caucasian male who underwent treatment with pembrolizumab for adenocarcinoma of the lung. He developed acute adrenal insufficiency and concomitant severe hypotension upon presentation. He did not require renal replacement therapy, rather his severe acute kidney injury resolved with hydration, normalization of blood pressures with vasopressors, and treatment with high-dose corticosteroids. His urinary indices (fractional excretion of urea, FEUrea) and clinical course were highly suspicious for acute tubular necrosis that resolved quickly after treating his underlying adrenalitis. The urinary sediment, proteinuria, and clinical course were not typical for the usually expected renal lesion of interstitial nephritis in patients treated with immune checkpoint inhibitors.

Circulating antineutrophil cytoplasmic antibodies (ANCAs) are the central pathogenic mechanism for a group of systemic and renal syndromes called the ANCA-associated vasculitis (AAV). The nomenclature has changed from eponymous labeling to granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and microscopic polyangiitis. These syndromes predominantly affect the pulmonary and renal systems. We also review the molecular pathology behind ANCAs and associated antigens and infections. Various clinical presentations, the multiple target organs affected, and diagnostic challenges involved in identifying these diseases are discussed. Treatment updates are also provided with regard to new studies and the now standard use of anti-CD-20 monoclonal antibodies as first-line therapy in all but the most aggressive presentations of this disease. Maintenance regimens and monitoring strategies for relapse of vasculitis and associated systemic complications are discussed.

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