Drug-induced nephrotoxicity Medical Services in China

Drug-induced nephrotoxicity refers to acute or chronic kidney injury caused by exposure to pharmacologic agents—either therapeutic doses of commonly prescribed medications or overdose/abuse scenarios. It is a leading cause of hospital-acquired acute kidney injury (AKI), accounting for approximately 19–25% of all AKI cases in inpatient settings globally. Pathophysiologically, nephrotoxicity arises through multiple mechanisms: direct tubular epithelial cell injury (e.g., aminoglycosides, cisplatin), intrarenal vasoconstriction and ischemia (e.g., NSAIDs, calcineurin inhibitors), crystal-induced tubular obstruction (e.g., acyclovir, sulfonamides, methotrexate), immune-mediated interstitial nephritis (e.g., PPIs, beta-lactams, diuretics), or glomerular damage (e.g., pamidronate, ifosfamide). Risk factors are multifactorial and include advanced age (>65 years), preexisting chronic kidney disease (CKD), diabetes mellitus, hypertension, heart failure, volume depletion, concurrent use of multiple nephrotoxic agents (e.g., dual RAAS blockade + NSAID), and genetic polymorphisms affecting drug metabolism (e.g., GSTM1 null genotype increasing cisplatin toxicity). Epidemiologically, incidence varies widely by clinical setting: among hospitalized adults, it affects 3–10% of patients receiving high-risk drugs; in oncology units, up to 30% of patients receiving platinum-based chemotherapy develop some degree of renal impairment. Critically, early recognition remains challenging due to nonspecific symptoms—including fatigue, nausea, decreased urine output, peripheral edema, and confusion—which often overlap with underlying illness or comorbidities. Untreated or severe cases may progress to dialysis-dependent kidney failure, prolonged hospitalization, or increased 90-day mortality (up to 25% in ICU-associated nephrotoxic AKI). Quality of life is significantly compromised: patients report persistent fatigue, cognitive slowing, sleep disturbances, anxiety about long-term kidney health, and limitations in physical activity and employment. Those requiring dialysis face substantial psychosocial burden, dietary restrictions, frequent clinic visits, and reduced health-related quality of life scores (measured by KDQOL-SF) comparable to end-stage heart failure. Importantly, many cases are preventable through vigilant medication review, dose adjustment per eGFR, hydration optimization, avoidance of drug combinations with synergistic toxicity, and real-time monitoring of serum creatinine and urinary biomarkers (e.g., NGAL, KIM-1) in high-risk populations.

Drug-induced nephrotoxicity (DIN) refers to acute or chronic kidney injury resulting from exposure to pharmacologic agents with inherent renal toxicity. Common culprits include aminoglycosides, vancomycin, amphotericin B, nonsteroidal anti-inflammatory drugs (NSAIDs), calcineurin inhibitors (e.g., cyclosporine, tacrolimus), cisplatin, radiocontrast media, and certain antivirals (e.g., tenofovir disoproxil fumarate). Early recognition—via serum creatinine trends, estimated glomerular filtration rate (eGFR) decline, urinary biomarkers (e.g., NGAL, KIM-1), and urinalysis—is critical to prevent irreversible tubulointerstitial fibrosis or glomerular damage. Management is stratified into conservative, pharmacologic, and procedural interventions, with emphasis on discontinuation of the offending agent as the cornerstone of therapy.

Conservative treatment constitutes the first-line and most universally applicable approach. It centers on immediate cessation of the nephrotoxic drug, followed by rigorous hemodynamic optimization. Intravascular volume status must be carefully assessed and corrected: isotonic crystalloids (e.g., 0.9% saline or balanced solutions such as lactated Ringer’s) are administered judiciously to maintain euvolemia—avoiding both hypovolemia (which exacerbates renal hypoperfusion) and fluid overload (which may precipitate pulmonary edema in compromised patients). Blood pressure targets should aim for mean arterial pressure ≥65 mmHg, with cautious use of vasopressors (e.g., norepinephrine) only if septic or cardiogenic shock coexists. Electrolyte imbalances—including hyperkalemia, metabolic acidosis, and hyponatremia—are managed per standard nephrology protocols: calcium gluconate for cardiac membrane stabilization, insulin-dextrose and sodium bicarbonate for acute hyperkalemia, and oral or IV sodium bicarbonate only in severe metabolic acidosis (pH <7.15) with preserved renal perfusion. Nutritional support emphasizes low-protein, low-sodium, and potassium-restricted diets during acute injury, transitioning to adequate protein intake (0.8–1.0 g/kg/day) during recovery to mitigate catabolism. Close monitoring of urine output, daily weights, serial creatinine, electrolytes, and fractional excretion of sodium (FeNa) guides ongoing management.

Pharmacologic interventions are adjunctive and agent-specific. For NSAID-induced afferent arteriolar vasoconstriction, withdrawal alone often suffices; however, in high-risk patients (e.g., those with heart failure or cirrhosis), short-term low-dose loop diuretics may be considered cautiously. In contrast, cisplatin nephrotoxicity is mitigated prophylactically with aggressive intravenous hydration (3–4 L/day pre- and post-infusion) and magnesium supplementation; amifostine—a thiol-based cytoprotectant—may be used selectively in oncology settings despite limited evidence for routine adoption. For aminoglycoside toxicity, once-daily dosing with therapeutic drug monitoring (peak/trough levels) reduces accumulation in proximal tubular cells. Vancomycin-induced nephrotoxicity is minimized via area-under-the-curve (AUC)-guided dosing rather than trough-only monitoring. In contrast-induced nephropathy (CIN), intravenous isotonic sodium bicarbonate or sodium chloride infusion remains first-line prophylaxis; while N-acetylcysteine (NAC) has shown inconsistent benefit in meta-analyses, it is still employed in high-risk populations (eGFR <45 mL/min/1.73m², diabetes, multiple myeloma) due to its antioxidant properties. Novel agents under investigation include endothelin receptor antagonists and SGLT2 inhibitors (e.g., empagliflozin), which demonstrate renoprotective effects in early-phase trials but lack definitive DIN-specific indications.

Surgical treatment plays a minimal role in DIN, as it is rarely indicated for the nephrotoxic process itself. However, urgent renal replacement therapy (RRT) may be required in cases of life-threatening complications: severe hyperkalemia (K⁺ >6.5 mmol/L with ECG changes), uremic encephalopathy or pericarditis, refractory fluid overload, or metabolic acidosis unresponsive to medical therapy. Modalities include intermittent hemodialysis (IHD), continuous renal replacement therapy (CRRT), or prolonged intermittent RRT (PIRRT), selected based on hemodynamic stability, ICU availability, and clinical urgency. CRRT is preferred in critically ill, unstable patients due to superior hemodynamic tolerance and precise fluid control. Surgical nephrectomy or renal artery intervention is not indicated for DIN unless coincident pathology exists (e.g., obstructive uropathy secondary to drug-induced crystalluria—such as with sulfadiazine or acyclovir—which may require ureteral stenting or nephrostomy). Lithotripsy or endoscopic stone removal may be necessary for obstructive nephropathy caused by drug crystals, though this is exceedingly rare in contemporary practice with improved hydration and drug selection.

China offers distinct advantages in the multidisciplinary management of DIN. First, integrated Traditional Chinese Medicine (TCM)–Western medicine protocols—endorsed by the National Health Commission—are increasingly incorporated into nephrology care. Evidence-based herbal formulations (e.g., Huangqi decoction, containing Astragalus membranaceus) have demonstrated anti-fibrotic and anti-inflammatory effects in preclinical models of tubular injury and are used adjunctively to support renal repair during recovery. Second, China’s national electronic health record system enables real-time pharmacovigilance: the China Adverse Drug Reaction Monitoring Center (CADRMC) rapidly identifies emerging DIN signals (e.g., recent alerts on herbal nephrotoxins like aristolochic acid analogues), facilitating nationwide safety alerts and prescribing guideline updates. Third, advanced diagnostic infrastructure—including widespread access to urinary biomarker assays (NGAL, cystatin C), point-of-care ultrasound for renal resistive index assessment, and AI-assisted eGFR trajectory modeling—is available even in tier-2 and tier-3 hospitals, enabling earlier detection and risk stratification. Finally, standardized clinical pathways for DIN—developed by the Chinese Society of Nephrology—ensure consistent application of KDIGO-aligned protocols across urban and rural centers.

Recovery advice emphasizes patient empowerment and longitudinal surveillance. Patients must receive explicit written documentation of the causative drug(s), with clear avoidance instructions and pharmacist-led medication reconciliation at discharge. Follow-up includes serum creatinine and eGFR every 1–2 weeks initially, then monthly until stabilization, with annual monitoring thereafter—even after apparent full recovery—to detect late-onset interstitial fibrosis. Lifestyle counseling focuses on hydration (1.5–2.0 L/day unless contraindicated), avoidance of over-the-counter NSAIDs and herbal supplements without nephrology consultation, and blood pressure control (<130/80 mmHg). Vaccination against influenza and pneumococcus is recommended to reduce infection-related AKI triggers. For patients with residual CKD, referral to a certified renal dietitian for personalized nutrition planning and enrollment in structured self-management programs (e.g., China’s ‘Healthy Kidney’ community initiative) improves long-term adherence and outcomes. Importantly, psychological support is integrated, as DIN-related anxiety about future medication use and chronic disease progression is common and associated with reduced health-related quality of life.