Hypokalemic Paralysis Secondary to Immune Checkpoint Inhibitor Therapy

Immune checkpoint inhibitors and acute kidney injury

As a new type of anti-tumor immunotherapy, immune checkpoint inhibitors (ICIs) have improved the prognosis of multiple malignancies. However, renal complications are becoming more frequent. Nephrotoxicity often manifests as acute kidney injury (AKI), and the most common histopathological type is acute tubulointerstitial nephritis (ATIN). Based on previous studies of the incidence and potential risk factors for nephrotoxicity, in this review, we describe the mechanism of AKI after ICIs treatment, summarize the incidence, risk factors, and outcomes of AKI, and discuss the diagnosis and management of immune checkpoint inhibitors-associated acute kidney injury (ICI-AKI). In addition, we review the current status of ICIs rechallenge and the therapeutic strategies of ICIs applied in kidney transplant recipients. Finally, we emphasize the importance of collaboration between nephrologists and oncologists to guide the treatment of ICIs and the management of renal complications.

Immunotherapy in oncology and the kidneys: a clinical review of the evaluation and management of kidney immune-related adverse events

Immune checkpoint inhibitors (ICI) are now widely used in the treatment of many cancers, and currently represent the standard of care for multiple malignancies. These agents enhance the T cell immune response to target cancer tissues, and have demonstrated considerable benefits for cancer outcomes. However, despite these improved outcomes, there are important kidney immune-related adverse events (iRAEs) associated with ICI. Acute tubulo-interstitial nephritis remains the most frequent kidney iRAE, however glomerular lesions and electrolytes disturbances are increasingly being recognized and reported. In this review, we summarize clinical features and identify risk factors for kidney iRAEs, and discuss the current understanding of pathophysiologic mechanisms. We highlight the evidence basis for guideline-recommended management of ICI-related kidney injury as well as gaps in current knowledge. We advocate for judicious use of kidney biopsy to identify ICI-associated kidney injury, and early use of corticosteroid treatment where appropriate. Selected patients may also be candidates for re-challenge with ICI therapy after a kidney iRAE, in view of current data on recurrent rates of kidney injury. Risk of benefits of re-challenge must be considered on an individual considering patient preferences and prognosis. Lastly, we review current knowledge of ICI use in the setting of patients with end-stage kidney disease, including kidney transplant recipients and those receiving dialysis, which suggest that these patients should not be summarily excluded from the potential benefits of these cancer therapies.

Immune checkpoint inhibitor induced nephrotoxicity: An ongoing challenge

Although immune checkpoint inhibitors (ICIs) have dramatically revolutionized the field of oncology over the last decade, severe immune-related adverse events (irAEs) are potentially life-threatening. In comparison with toxicities involving the skin, gastrointestinal tract and endocrine system, nephrotoxicity is less common but often underestimated due to difficult diagnosis. Management usually consists of treatment discontinuation and/or corticosteroid use. In this review, we summarize current knowledge of ICI-induced nephrotoxicity, evaluating drawbacks and future perspectives.

Renal Complications Related to Checkpoint Inhibitors: Diagnostic and Therapeutic Strategies

Immune checkpoint inhibitors (ICI) targeting CTLA-4 and the PD-1/PD-L1 axis have unprecedentedly improved global prognosis in several types of cancers. However, they are associated with the occurrence of immune-related adverse events. Despite their low incidence, renal complications can interfere with the oncologic strategy. The breaking of peripheral tolerance and the emergence of auto- or drug-reactive T-cells are the main pathophysiological hypotheses to explain renal complications after ICI exposure. ICIs can induce a large spectrum of renal symptoms with variable severity (from isolated electrolyte disorders to dialysis-dependent acute kidney injury (AKI)) and presentation (acute tubule-interstitial nephritis in >90% of cases and a minority of glomerular diseases). In this review, the current trends in diagnosis and treatment strategies are summarized. The diagnosis of ICI-related renal complications requires special steps to avoid confounding factors, identify known risk factors (lower baseline estimated glomerular filtration rate, proton pump inhibitor use, and combination ICI therapy), and prove ICI causality, even after long-term exposure (weeks to months). A kidney biopsy should be performed as soon as possible. The treatment strategies rely on ICI discontinuation as well as co-medications, corticosteroids for 2 months, and tailored immunosuppressive drugs when renal response is not achieved.

Acute interstitial nephritis associated with immune checkpoint inhibitors: a single-centre experience

BACKGROUND

Checkpoint inhibitors (CPIs) are used to treat solid organ metastatic malignancies. They act by triggering a vigorous immune response against tumoural cells, preventing their proliferation and metastasis. However, this is not a selective response and can cause immune-related adverse events (irAEs). The kidney can potentially be damaged, with an incidence of irAEs of 1-4%. The most frequent type of toxicity described is acute interstitial nephritis (AIN).

METHODS

We conducted a study of patients with solid organ metastatic malignancies treated with immunotherapy who developed acute renal injury and underwent kidney biopsy in the last 14 months at the Vall d'Hebron University Hospital.

RESULTS

In all, 826 solid organ malignancies were treated with immunotherapy in our centre, 125 of them (15.1%) developed acute kidney injury (AKI), 23 (18.4% of AKI) visited the nephrology department and 8 underwent kidney biopsy. The most frequent malignancy was lung cancer, in five patients (62%), followed by two patients (25%) with melanoma and one patient (12%) with pancreatic cancer. Four patients (50%) had already received previous oncological therapy, and for the remaining four patients (50%), CPI was the first-line therapy. Five patients (62%) were treated with anti-programmed cell death protein 1, three patients (37%) received anti-programmed death ligand 1 and two (25%) patients were treated in combination with anti-cytotoxic T-lymphocyte antigen 4. The time between the start of CPI and the onset of the AKI ranged from 2 to 11 months. The most frequent urine findings were subnephrotic-range proteinuria, with a mean protein:creatinine ratio of 544 mg/g (standard deviation 147) and eosinophiluria. All patients were biopsied after being diagnosed with AIN. Three patients (37%) received treatment with pulses of methylprednisolone 250-500 mg/day and five patients (62%) received prednisone 1 mg/kg/day. Seven patients (87%) experienced recovery of kidney function and one patient (12%) progressed to chronic kidney disease.

CONCLUSIONS

We report on eight patients with CPI-related AIN diagnosed in the last 14 months at our centre. The novel immunotherapy treatment of metastatic solid organ malignancies carries a higher risk of irAEs. The kidney is one of the most commonly affected organs, frequently presenting as an AIN and exhibiting a favourable response to steroid treatment.

Metabolic and Nutritional Disorders Following the Administration of Immune Checkpoint Inhibitors: A Pharmacovigilance Study

BACKGROUND

Although several metabolic and nutritional disorders (MNDs) have been reported in the recipients of immune checkpoint inhibitors (ICIs), these events have not been fully captured and comprehensively characterized in real-world population.

OBJECTIVES

To provide complete metabolic and nutritional toxicity profiles after ICIs (single and combined) initiation through an integrated big database.

METHODS

Reporting odds ratios (ROR) and information component (IC) based on statistical shrinkage transformation were utilized to perform disproportionality analysis using the US Food and Drug Administration Adverse Events Reporting System. Both ROR and IC were used to calculate disproportionality when compared with the whole database, but only ROR was used when comparison was made for different ICI strategies. Only when both the lower limits of 95% confidence intervals (CIs) for ROR (ROR₀₂₅) and IC (IC₀₂₅) exceeded specified threshold values (1 and 0, respectively) was regarded as a signal.

RESULTS

A total of 29,294,335 records were involved and 8,662 records were for MNDs in patients exposed to ICIs. Statistically significant association was detected between ICIs use and total MNDs (IC₀₂₅/ROR₀₂₅ = 1.06/2.19). For monotherapy, three ICI monotherapies (anti-PD-1, anti-PDL-1, and anti-CTLA-4) were all disproportionately associated with MNDs. Statistically significant differences in reporting frequencies also emerged when comparing anti-PD-1 with anti-PD-L1/anti-CTLA-4 monotherapy, with RORs of 1.11 (95%CI 1.01-1.21), and 1.35 (95%CI 1.23-1.48), respectively. Notably, combination therapy was associated with a higher reporting frequency of theses toxicities compared to monotherapy with a ROR of 1.56 (95%CI 1.48-1.64). Additionally, disproportionality analysis at High-level Group Term level highlighted eight broad entities of MNDs. Further disproportionality analysis at Preferred Term level indicated a wide range and varied strength of signals. For ICI monotherapy, nivolumab and pembrolizumab showed the broadest spectrum of MNDs. For combination therapy, a variety of signals were detected for nivolumab + ipilimumab therapy even comparable to two PD-1 monotherapies.

CONCLUSION

Metabolic and nutritional complications could be provoked by ICI monotherapy (especially anti-PD-1) and further reinforced by combination therapy. Clinicians and patients should be informed about these potential risks that might be encountered in real-world practice. Aforehand education and regular monitoring of related biochemical parameters (calcium, sodium, potassium, protein) are recommended to ensure better cancer survivorship.

Nephrotoxicity of Immune Checkpoint Inhibitors: Acute Kidney Injury and Beyond

Immune checkpoint inhibitors (ICIs) are novel humanized monoclonal antibodies that release the brakes on the immune system, resulting in the destruction of tumor cells. ICIs are approved for a variety of hematological and solid organ malignancies, and the list has been growing since the approval of ipilimumab in 2011. ICIs are associated with a variety of immune-related adverse events (irAEs). irAEs commonly affect the skin, the gastrointestinal (GI) tract, and the endocrine system. Acute kidney injury (AKI) due to ICIs (ICI-AKI) occurs in a minority of patients, and it is usually due to acute tubulointerstitial nephritis (ATIN). Treatment with corticosteroids is usually successful. There have been reports of electrolyte disorders due to ICIs, including hyponatremia, hypocalcemia, hypokalemia, and Fanconi syndrome. The diagnosis of electrolyte disorders requires vigilance and routine laboratory monitoring.

Acute Interstitial Nephritis in a Patient with Non-Small Cell Lung Cancer under Immunotherapy with Nivolumab

Immune-checkpoint-inhibitors (ICPIs) represent a novel class of immunotherapy against several malignancies. These agents are associated with several "immune-mediated" adverse effects, but the reported renal toxicity of ICPIs is less well defined. We present the case of a 60-year-old man with a history of non-small cell lung cancer, who developed acute kidney injury (AKI) approximately 3.5 months after initiation of immunotherapy with nivolumab. Urinalysis revealed sterile pyuria, without microscopic hematuria or proteinuria. Immunological examination was negative. A renal biopsy showed severe interstitial inflammatory infiltration of T-cells, monocytes, and eosinophils without interstitial granulomas and normal appearance of glomeruli, indicating acute interstitial nephritis (AIN) as the cause of AKI. After a short-term course of corticosteroids and permanent nivolumab discontinuation, partial recovery of renal function was noted. AIN is a rare adverse effect of ICPIs that mandates the close monitoring of renal function in patients under immunotherapy with these agents.