Kidney Injury Prevention

Medication Management

Avoid nephrotoxic medications, including NSAIDs, to prevent kidney injury, as recommended by the American Diabetes Association 1
Consider temporary discontinuation of potentially nephrotoxic medications to prevent renal dysfunction, as suggested by the American Society of Nephrology 2

Monitor creatinine closely and evaluate for other causes if creatinine increases >0.3 mg/dL, and consider nephrology consultation, as recommended by the American Society of Clinical Oncology 3
Hold potentially nephrotoxic medications and consider corticosteroids if immune-mediated cause is suspected when creatinine increases 2-3× above baseline, as recommended by the American Society of Clinical Oncology 3
Essential tests for diagnosing CPK elevation include renal function tests, electrolytes, urinalysis for myoglobinuria, liver function tests, and anti-AChR antibodies and anti-striated muscle antibodies for myositis suspicion, as recommended by the American College of Rheumatology and the American Society of Clinical Oncology 4, 3
Determine CPK isoenzymes to differentiate cardiac from skeletal muscle origin, and assess for potential causes, including recent strenuous exercise, current medications, and recent viral illness, as recommended by the American Society of Clinical Oncology 4

Consider inflammatory markers and autoantibody testing if immune-mediated myositis is suspected, as recommended by the American College of Physicians 3
For patients with immune checkpoint inhibitor-related myositis, consider prednisone 0.5-1 mg/kg/day if muscle weakness is present, and grade the severity of CPK elevation to guide treatment, as stated in the Journal of Clinical Oncology 3
Consider prednisone 1-1.5 mg/kg/day for Grade 2 immune checkpoint inhibitor-related myositis, and permanently discontinue therapy, administer high-dose corticosteroids, and consider IVIG or plasmapheresis for severe cases (Grade 3-4), as recommended by the National Comprehensive Cancer Network 4, 3

Aggressive fluid resuscitation (3-6L per day) and daily monitoring of CPK, renal function, and electrolytes until improvement is recommended for patients with rhabdomyolysis, as suggested by the International Society of Nephrology and the European Society of Intensive Care Medicine 5
The following table summarizes the fluid intake volumes for rhabdomyolysis:
Rhabdomyolysis Severity Fluid Intake Volume
Severe (CPK >15,000 IU/L) > 6L
Moderate 3-6L per day [6]

Rhabdomyolysis Severity	Fluid Intake Volume
Severe (CPK >15,000 IU/L)	> 6L
Moderate	3-6L per day [6]

Patients can be considered for discharge when CPK levels are trending down consistently, renal function is stable, electrolytes are normalized, and adequate oral fluid intake is established, as recommended by the Anaesthesia guidelines 6, 7, 5
Patients with CPK levels above 5,000 IU/L should be admitted for monitoring and management, especially if they have risk factors for acute kidney injury or show signs of rhabdomyolysis, as the risk of acute kidney injury significantly increases, as suggested by the Anaesthesia guidelines 6
All suspected cases of immune checkpoint inhibitor-related myositis with elevated CPK should be admitted for evaluation and referral to rheumatology or neurology, as recommended by the American Society of Clinical Oncology 7
Nephrology consultation should be considered for patients with declining renal function or CPK >15,000 IU/L, as recommended by the American College of Physicians 3