Nephrotic Syndrome

Obtain serum creatinine/eGFR, serum albumin, quantitative proteinuria, urinalysis with microscopy, blood pressure, weight, and medication exposure at presentation. Escalate urgently for rapidly worsening kidney function, oliguria, severe hypertension, pulmonary edema, suspected sepsis, or symptoms of pulmonary embolism, deep-vein thrombosis, renal-vein thrombosis, stroke, or acute limb ischemia. Nephrotic syndrome carries both venous and arterial thromboembolic risk; reported overall risk can be as high as 40%, varying with disease severity and etiology.ScienceDirectScienceDirectA Systematic Review of Prophylactic Anticoagulation in Nephrotic Syndrome

Use the thrombotic presentation to direct imaging rather than screening indiscriminately: obtain compression ultrasonography for unilateral limb symptoms and chest imaging appropriate to suspected pulmonary embolism. A confirmed thrombotic event requires therapeutic anticoagulation; the unresolved decision is primary prophylaxis, for which evidence remains limited and risk-benefit assessment must weigh nephrotic severity, underlying disease, and bleeding risk.ScienceDirectScienceDirectA Systematic Review of Prophylactic Anticoagulation in Nephrotic Syndrome

If edema is accompanied by dyspnea, hypoxemia, or pulmonary congestion, determine whether volume excess, pulmonary embolism, or cardiac amyloid is contributing. In suspected AL amyloidosis, renal involvement is defined by albuminuria of at least 0.5 g/24 h; cardiac staging incorporates cardiac biomarkers and has direct prognostic implications.ASHASHAmyloid consults do not have to be vexing

In children, minimal change disease is the leading cause of nephrotic syndrome; it also occurs in adults.ScienceDirect+1ScienceDirectPrimary glomerulonephritidesScienceDirectGlomerular Diseases Across Lifespan: Key Differences in ... In an otherwise typical child, response to initial glucocorticoid therapy helps classify the course as steroid-sensitive, frequently relapsing, steroid-dependent, or steroid-resistant and determines the need for steroid-sparing treatment.The Lancet+2The LancetChildhood nephrotic syndromeThe LancetRituximab for childhood-onset, complicated, frequentlyScienceDirectKDIGO 2025 Clinical Practice Guideline for the ...

In adults, assess specifically for membranous nephropathy, minimal change disease, focal segmental glomerulosclerosis (FSGS), and systemic causes. Membranous nephropathy principally affects middle-aged and older adults and may be secondary to hepatitis B, hepatitis C, malignancy, systemic lupus erythematosus, or drugs such as gold and penicillamine.ScienceDirectScienceDirectPrimary glomerulonephritides A positive exposure or systemic branch should trigger targeted treatment of the associated disease rather than automatic classification as primary membranous nephropathy.

Evaluate for amyloidosis when nephrotic proteinuria coexists with a plasma-cell disorder, unexplained cardiomyopathy, neuropathy, hepatomegaly, or multisystem disease. For AL amyloidosis, renal staging uses eGFR 50 mL/min/1.73 m² or less and proteinuria 5 g/24 h or more: meeting neither threshold is stage I, either threshold stage II, and both stage III.ASHASHAmyloid consults do not have to be vexing

Consider inherited basement-membrane disease when hematuria, hearing loss, ocular findings, or family history coexist with proteinuria. Alport syndrome can progress to FSGS histology through podocyte loss; males with X-linked disease and individuals with autosomal recessive disease may develop nephrotic-range proteinuria or nephrotic syndrome, whereas this is rare in heterozygous autosomal disease and should prompt assessment for an additional contributor.Oxford AcademicOxford AcademicDiagnosis, management and treatment of the Alport syndrome – 2024 guideline on behalf of ERKNet, ERA and ESPN | Nephrology Dialysis Transplantation | Oxford Academic

Optimize blood pressure and antiproteinuric therapy with a maximally tolerated ACE inhibitor or angiotensin receptor blocker when not contraindicated. Renin-angiotensin system blockade is central supportive therapy across proteinuric glomerular disease, with the treatment goal of lowering proteinuria and controlling blood pressure.Oxford Academic+1Oxford AcademicDiagnosis, management and treatment of the Alport syndrome – 2024 guideline on behalf of ERKNet, ERA and ESPN | Nephrology Dialysis Transplantation | Oxford Academicema europa euOrphan Maintenance Assessment Report Monitor creatinine, potassium, blood pressure, and volume status after initiation or dose escalation.

For Alport syndrome, the cited 2024 guideline identifies ramipril as the most extensively studied agent: start 1 to 2 mg/m²/day and titrate to a target maximum of 6 mg/m²/day.Oxford AcademicOxford AcademicDiagnosis, management and treatment of the Alport syndrome – 2024 guideline on behalf of ERKNet, ERA and ESPN | Nephrology Dialysis Transplantation | Oxford Academic This dose is disease-specific evidence and should not be extrapolated as a universal nephrotic-syndrome dosing rule.

Assess prophylactic anticoagulation separately from treatment-dose anticoagulation. Earlier KDIGO guidance recommended prophylaxis only in idiopathic membranous nephropathy, and the supporting evidence was acknowledged to be limited and low quality.ScienceDirectScienceDirectA Systematic Review of Prophylactic Anticoagulation in Nephrotic Syndrome Use an individualized decision that incorporates membranous histology, nephrotic severity, prior thrombosis, immobility, and bleeding risk rather than applying a universal prophylaxis rule to all nephrotic presentations.

Reassess urine protein excretion, serum albumin, eGFR, blood pressure, weight, and treatment toxicity longitudinally. Persistent nephrotic syndrome despite therapy is a progression signal in primary membranous nephropathy and should prompt reassessment of adherence, secondary causes, histologic context, and the selected immunosuppressive regimen.ScienceDirectScienceDirectThe outcomes of primary membranous nephropathy treated with cyclophosphamide are superior to calcineurin inhibitors in patients with renal vascular lesions: A multi-center retrospective cohort study - ScienceDirect

In complicated childhood steroid-dependent nephrotic syndrome, rituximab is an effective long-term steroid-sparing option and can support withdrawal of calcineurin inhibitors.The Lancet+1The LancetRituximab for childhood-onset, complicated, frequentlyNatureRituximab therapy in nephrotic syndrome: implications for patients' management | Nature Reviews Nephrology In adult minimal change disease with frequently relapsing or steroid-dependent disease, available series and meta-analysis data show reduced relapses and reduced glucocorticoid-sparing immunosuppression after rituximab; reported response rates across studies ranged from 63% to 100%, but these data are largely nonrandomized and should not be generalized to steroid-resistant FSGS.PubMedPubMedRituximab in Minimal Change Disease: Mechanisms of Action and Hypotheses for Future Studies - PMC

For steroid-resistant nephrotic syndrome that has not responded to calcineurin inhibitors, counsel that rituximab efficacy is limited, especially with FSGS.NatureNatureRituximab therapy in nephrotic syndrome: implications for patients' management | Nature Reviews Nephrology This pattern should prompt renewed scrutiny for genetic, adaptive, infectious, drug-associated, or inherited causes rather than serial empiric B-cell depletion.

For primary membranous nephropathy with nephrotic syndrome and risk of disease progression, guideline-recognized first-line approaches include rituximab, cyclophosphamide combined with glucocorticoids, and calcineurin inhibitor-based treatment.ScienceDirectScienceDirectThe outcomes of primary membranous nephropathy treated with cyclophosphamide are superior to calcineurin inhibitors in patients with renal vascular lesions: A multi-center retrospective cohort study - ScienceDirect Selection requires an explicit tradeoff: calcineurin inhibitors can reduce proteinuria and achieved higher remission-related outcomes than cyclophosphamide at 6 months in a meta-analysis, but differences were no longer significant by 12 months; cyclosporine did not improve renal function or provide durable benefit in an earlier progressive-disease trial.Kidney International+1Kidney InternationalMembranous nephropathy: When and how to treat - Kidney InternationalScienceDirectCalcineurin inhibitors versus cyclophosphamide for idiopathic membranous nephropathy: A systematic review and meta-analysis of 21 clinical trials - ScienceDirect

Reserve disease-specific therapy for amyloidosis and systemic autoimmune or infection-associated glomerular disease for the confirmed systemic diagnosis. In AL amyloidosis, renal stage and cardiac biomarker stage quantify organ involvement and should guide urgency and multidisciplinary hematology-nephrology treatment planning.ASHASHAmyloid consults do not have to be vexing

Arrange expedited nephrology evaluation for adults with new nephrotic syndrome, declining eGFR, active urine sediment, suspected membranous nephropathy, suspected amyloid, recurrent thromboembolism, or steroid-resistant disease. Kidney biopsy and integrated pathology are often needed to distinguish potentially treatable primary disease from secondary, genetic, or infiltrative disease addressed in KDIGO glomerular-disease guidance.ScienceDirectScienceDirectExecutive summary of the KDIGO 2021 Guideline for the ...

Escalate to hematology with suspected AL amyloidosis, particularly when renal protein loss coexists with elevated cardiac biomarkers or echocardiographic myocardial involvement. Cardiac staging thresholds include NT-proBNP 1,800 ng/L or greater, cardiac troponin T 0.025 ng/mL or greater, and difference in involved versus uninvolved free light chains of 180 mg/L or greater in the 2012 Mayo system.ASHASHAmyloid consults do not have to be vexing

For children with frequent relapse, steroid dependence, calcineurin-inhibitor dependence, or steroid resistance, involve pediatric nephrology before repeated treatment cycles. Rituximab has demonstrated long-term utility in complicated steroid- and calcineurin-inhibitor-dependent childhood disease, but treatment selection must be linked to the response phenotype rather than nephrotic syndrome alone.The Lancet+1The LancetRituximab for childhood-onset, complicated, frequentlyScienceDirectKDIGO 2025 Clinical Practice Guideline for the ...