Acute Kidney Injury (AKI) is a recognized complication in patients receiving immune checkpoint inhibitors (ICIs), a class of monoclonal antibodies targeting immune regulatory pathways to enhance anti-tumor immunity. ICIs are widely used in the treatment of various cancers, including melanoma, lung cancer, renal cell carcinoma, and others. Despite their clinical efficacy, ICIs have been associated with immune-related adverse events (irAEs), including renal toxicities such as AKI.
### Incidence of AKI in Patients Receiving ICIs
The incidence of AKI in patients treated with ICIs ranges from approximately **2% to 5%**, depending on the study population, type of ICI, and diagnostic criteria used. While renal toxicity is less common compared to other irAEs (e.g., dermatologic, gastrointestinal, or endocrine complications), AKI remains a clinically significant concern due to its potential impact on patient outcomes and treatment continuity.
### Causes of AKI in ICI Recipients
The etiology of AKI in patients on ICIs often includes immune-mediated mechanisms, reflecting the underlying mode of action of these agents. Common causes of AKI include:
1. **ICI-Mediated Acute Tubulointerstitial Nephritis (ATI):**
- This is the most prevalent renal irAE associated with ICIs.
- Thought to result from T cell infiltration and auto-reactivity against renal tubular antigens.
- ATI typically manifests with elevated creatinine levels and inflammatory markers but may appear without overt systemic symptoms.
2. **Glomerular Diseases:**
- Less commonly than ATI, ICIs can trigger immune-mediated glomerular pathologies, such as membranous nephropathy or minimal change disease.
3. **Non-Immune-Mediated Causes:**
- Volume depletion or dehydration from diarrhea and vomiting, which are common side effects of ICIs, can lead to pre-renal AKI.
- Co-medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), antibiotics, or radiographic contrast agents can contribute to renal damage.
- Underlying malignancy itself or tumor lysis syndrome may also contribute to AKI.
4. **Concurrent irAEs:**
- Systemic irAEs, such as colitis or hepatitis, may indirectly contribute to AKI through multi-organ involvement or hypotension.
### Risk Factors for AKI in ICI-Treated Patients
Several risk factors predispose patients receiving ICIs to AKI:
1. **Patient-Specific Factors:**
- Pre-existing chronic kidney disease (CKD) or reduced baseline renal function.
- Older age, given the reduced renal reserve seen in aging populations.
2. **ICI Treatment Characteristics:**
- Combination therapy with multiple ICIs (e.g., anti-PD-1 with anti-CTLA-4 agents) has been linked to higher rates of organ toxicity, including AKI.
- Higher doses or longer durations of therapy.
3. **Concurrent Medications:**
- Use of nephrotoxic drugs (e.g., antibiotics, NSAIDs).
- Proton pump inhibitors (PPIs) have been implicated as potential contributors to ATI when used in conjunction with ICIs.
4. **Systemic Factors:**
- Presence of other irAEs, indicating heightened immune system activation and a predisposition to autoimmune reactions.
- Concomitant infections, sepsis, or tumor-related complications.
### Clinical Management
Early recognition and management of AKI in ICI-treated patients are crucial. The approach typically involves:
- **Renal Biopsy:** In cases where the etiology of AKI is unclear, biopsy can differentiate between immune-mediated ATI and other causes.
- **Discontinuation or Pause of ICIs:** Temporary cessation of therapy may be required.
- **Immunosuppressive Therapy:** Steroids (e.g., prednisone or methylprednisolone) are commonly used to treat ICI-induced ATI or glomerular diseases.
- **Supportive Care:** Addressing pre-renal factors like dehydration or discontinuing nephrotoxic medications.
### Conclusion
AKI is an important complication in patients receiving ICIs, predominantly driven by immune-mediated mechanisms such as acute tubulointerstitial nephritis. Recognizing risk factors and implementing timely management strategies can reduce renal morbidity and optimize oncological outcomes. Further studies are needed to elucidate the precise mechanisms and establish standardized diagnostic and therapeutic protocols. |
求助已关闭
30