Interferon-α

Glomerular Injury / Proteinuria.

Rare; best characterized by an 11-case biopsy series, disproportionately in Black patients (APOL1).

Source: Markowitz et al., CJASN 2010

Reported injury signatures: Glomerular Injury / Proteinuria, Thrombotic Microangiopathy.

1. Glomerular Injury / ProteinuriaPrimary
2. Thrombotic MicroangiopathySecondary

Subacute (~1–6 weeks) — Develops over weeks to months of therapy.

• Black race / APOL1 high-risk genotype

• Dose-reduce or avoid the pegylated interferon-α formulations at CrCl <50 mL/min, per label — they accumulate in renal impairment

• Baseline and serial urine protein quantification (UPCR or spot ratio) every 4-8 weeks during therapy; new or rising proteinuria is the earliest signal of IFN glomerulopathy.
• Monitor blood pressure and check for new edema, which often accompany the emerging nephrotic syndrome.
• Screen for TMA when there is thrombocytopenia, falling hemoglobin, schistocytes on smear, elevated LDH, and low haptoglobin alongside renal dysfunction.
• Refer for kidney biopsy when nephrotic-range proteinuria or unexplained AKI develops, and hold the drug pending evaluation.
• Serum creatinine/eGFR during therapy to detect declining renal function

• Markowitz et al. (J Am Soc Nephrol 2010) - landmark renal-biopsy series linking all three interferon types (especially IFN-β) to collapsing and non-collapsing FSGS with nephrotic-range proteinuria.
• Nichols et al. / pharmacovigilance and pooled case-series reviews of interferon-associated thrombotic microangiopathy, characterizing IFN-β > IFN-α TMA presenting with AKI, hypertension, and hemolysis often after prolonged exposure.
• Multiple published case series of pegylated IFN-α (± ribavirin) for hepatitis C reporting biopsy-proven FSGS, minimal change disease, and membranoproliferative/cryoglobulinemic GN.

• All three interferons can cause glomerular disease, but the classic IFN lesion is collapsing FSGS presenting with abrupt heavy proteinuria and rapidly declining GFR.
• Tubuloreticular inclusions ('interferon footprints') in glomerular endothelium on electron microscopy are a histologic clue to an interferon-driven process.
• Withdrawal of the drug is the primary treatment and often the main hope for renal recovery; steroid response is inconsistent and collapsing FSGS frequently progresses to ESKD despite stopping.
• Interferon-associated TMA is a distinct, often delayed and severe presentation (AKI, malignant-range hypertension, microangiopathic hemolysis) that does not respond to plasma exchange and hinges on prompt discontinuation.

Each recommendation below is this atlas's faithful summary of the source, not a quotation from it — follow the PubMed link for the wording the society published. Summaries may be superseded; consult the current full text and individualize to the patient.

• ADQI (2026) — The nephrotoxic effects of anti-cancer therapies: consensus report of the 34th Acute Disease Quality Initiative workgroupProvides expert-based statements (modified Delphi) on preventing and managing cisplatin/platinum-associated AKI, including isotonic IV hydration, attention to volume status and concomitant nephrotoxins, and incorporates evidence that IV magnesium supplementation may reduce cisplatin-associated AKI; emphasizes risk stratification and standardized AKI definitions.Nat Rev Nephrol · PMID 41361704
• SIRM (2022) — SIRM-SIN-AIOM: appropriateness criteria for evaluation and prevention of renal damage in the patient undergoing contrast medium examinations-consensus statements from Italian College of Radiology (SIRM), Italian College of Nephrology (SIN) and Italian Association of Medical Oncology (AIOM)Recommends eGFR-based renal risk assessment and pre/post-contrast isotonic saline or sodium bicarbonate hydration; advises maintaining a 5-7 day interval between iodinated contrast administration and cisplatin in cancer patients to reduce additive nephrotoxicity.Radiol Med · PMID 35303246
• KDIGO (2020) — KDIGO Controversies Conference on onco-nephrology: understanding kidney impairment and solid-organ malignancies, and managing kidney cancerIdentifies platinum compounds (especially cisplatin) as leading cytotoxic causes of acute tubular injury, AKI, and electrolyte/magnesium wasting; calls for interdisciplinary onco-nephrology care, accurate GFR estimation, and individualized drug dosing in patients with reduced kidney function.Kidney Int · PMID 33126977
• KDIGO (2020) — KDIGO Controversies Conference on onco-nephrology: kidney disease in hematological malignancies and the burden of cancer after kidney transplantationAddresses chemotherapy-associated AKI/CKD in hematologic cancer, GFR estimation and chemotherapy dosing in patients with reduced kidney function, and management priorities and research gaps for onco-nephrology care.Kidney Int · PMID 33276867
• ADDIKD (2025) — Integrating International Consensus Guidelines for Anticancer Drug Dosing in Kidney Dysfunction (ADDIKD) into everyday practiceProvides GRADE-based, drug-specific dose-adjustment recommendations for anticancer agents in kidney dysfunction (illustrated for methotrexate, cisplatin, carboplatin and nivolumab); the recommendations build on Part 1's standardised CKD-EPI eGFR assessment rather than Cockcroft-Gault creatinine clearance.EClinicalMedicine · PMID 40290844
• ADDIKD (2025) — Aligning kidney function assessment in patients with cancer to global practices in internal medicineThree consensus recommendations: assess kidney function by GFR (measured GFR or CKD-EPI eGFR), classify it using KDIGO categories, and use this uniform approach to dose anticancer drugs — moving cancer medicine away from Cockcroft-Gault estimated creatinine clearance.EClinicalMedicine · PMID 40290845
• ADDIKD (2025) — A methodology for determining dosing recommendations for anticancer drugs in patients with reduced kidney functionEstablishes that, where RCT evidence is lacking, anticancer drug dosing recommendations in kidney dysfunction should be derived by critically appraising observational literature via GRADE combined with structured international multidisciplinary consensus voting.EClinicalMedicine · PMID 40290846
• KDIGO (2013) — Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1)Defines/stages AKI by serum creatinine and urine output; emphasizes avoiding nephrotoxins, maintaining euvolemia/perfusion, dose-adjusting drugs to kidney function, and monitoring high-risk patients — the framework applied to nephrotoxic anti-cancer agents.Crit Care · PMID 23394211
• KDIGO (2024) — Executive summary of the KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease: known knowns and known unknownsEvaluate and risk-stratify CKD, manage to delay progression and its complications, and practise explicit medication management and drug stewardship — the framework the atlas's G1–G5 eGFR banding and every renal dose-adjustment recommendation sit inside. Because the guideline excludes dialysis and transplant recipients by its own statement of scope, its recommendations do not carry to those settings, where this atlas's dialyzability and post-transplant guidance rests on other sources.Kidney Int · PMID 38519239
• KDIGO (2021) — Executive summary of the KDIGO 2021 Guideline for the Management of Glomerular DiseasesProvides the staging/treatment framework for drug-associated glomerular lesions (e.g., bisphosphonate- and interferon-related collapsing FSGS, VEGF-inhibitor podocytopathy/proteinuria), including immunosuppression and supportive RAAS-blockade strategies.Kidney Int · PMID 34556300
• KDIGO (2024) — Executive summary of the KDIGO 2024 Clinical Practice Guideline for the Management of ANCA-Associated VasculitisUpdates immunosuppressive induction (rituximab/cyclophosphamide), incorporates avacopan and lower-dose or glucocorticoid-sparing regimens — the management framework for drug- and checkpoint-inhibitor-associated ANCA/pauci-immune glomerulonephritis.Kidney Int · PMID 38388147
• KDIGO (2024) — Executive summary of the KDIGO 2024 Clinical Practice Guideline for the Management of Lupus NephritisUpdates first-line lupus nephritis therapy to combination immunosuppression with the addition of belimumab or a calcineurin inhibitor (voclosporin) — informs management of immune-complex/lupus-like glomerulonephritis encountered with immunotherapy.Kidney Int · PMID 38182299
• KDIGO (2025) — Executive summary of the KDIGO 2025 Clinical Practice Guideline for the Management of Immunoglobulin A Nephropathy (IgAN) and Immunoglobulin A Vasculitis (IgAV)Encourages liberal kidney biopsy and stricter proteinuria control (<0.5 g/d, ideally <0.3 g/d) with RAAS blockers, SGLT2 inhibitors, and targeted-release budesonide — the framework for IgA-dominant glomerular lesions, including those triggered by immune-modulating cancer therapy.Kidney Int · PMID 40975525