For Patients & General Readers

Nephrotic syndrome is a kidney disorder that causes the body to lose too much protein in the urine. This can lead to swelling, particularly in the legs and feet, and can affect people of all ages, though it's more common in children. It's important to manage because it can lead to serious complications if left untreated.

Clinical Overview

Nephrotic syndrome is characterized by heavy proteinuria (>3.5 g/day in adults, or >40 mg/m²/hr in children), hypoalbuminemia, edema, and hyperlipidemia. It results from damage to the glomerular filtration barrier, leading to increased permeability to proteins.

Clinical Presentation

Generalized edema, often starting periorbitally and progressing to lower extremities, ascites, and pleural effusions.
Significant proteinuria detected on urinalysis.
Hypoalbuminemia (<3.0 g/dL).
Hyperlipidemia, with elevated cholesterol and triglycerides.
Weight gain due to fluid retention.
Foamy urine, indicative of heavy proteinuria.

Signs & Symptoms

Symptoms (Patient-Reported)

Swelling (edema) in the face, hands, feet, and abdomen.
Shortness of breath (if pleural effusions are present).
Fatigue and weakness.
Reduced urine output.
Weight gain.
Loss of appetite.

Signs (Clinician-Observed)

Pitting edema of the lower extremities.
Periorbital edema.
Ascites.
Pleural effusions.
Normal or mildly elevated blood pressure.

Differential Diagnoses

Condition	Distinguishing Feature
Nephritic Syndrome	Characterized by hematuria, hypertension, and renal insufficiency in addition to proteinuria, often with cellular casts.
Congestive Heart Failure	Edema and shortness of breath can be present, but typically associated with cardiac abnormalities, elevated JVP, and absence of significant proteinuria.
Liver Cirrhosis	Can cause hypoalbuminemia and ascites, but typically associated with stigmata of chronic liver disease and normal renal function.
Protein-Losing Enteropathy	Hypoalbuminemia and edema can occur, but the primary issue is excessive protein loss from the gastrointestinal tract, not the kidneys.
Hypothyroidism	Can cause generalized edema and fatigue, but typically associated with other signs of hypothyroidism and absence of significant proteinuria.
Minimal Change Disease	A common cause of nephrotic syndrome in children, characterized by normal glomeruli on light microscopy and effacement of podocyte foot processes on electron microscopy.

Red Flags — Seek Immediate Care

Rapidly worsening edema and respiratory distress, suggestive of pulmonary edema or effusions.
Signs of infection (fever, chills), as patients are immunocompromised due to hypoalbuminemia and potential immunosuppressive therapy.
Thromboembolic events (e.g., deep vein thrombosis, pulmonary embolism), due to hypercoagulability.
Acute kidney injury, indicating severe glomerular damage or complications.

Key Investigations

Urinalysis with quantitative protein measurement (e.g., 24-hour urine protein excretion or protein-to-creatinine ratio).
Serum albumin and lipid profile.
Renal function tests (serum creatinine, BUN, eGFR).
Electrolytes, calcium, and phosphate levels.
Serological tests for underlying causes (e.g., ANA, ANCA, anti-GBM antibodies, complement levels, viral serologies).
Renal biopsy may be indicated to determine the specific glomerular pathology and guide management, especially in adults or cases of steroid resistance.

Management Overview

Management focuses on treating the underlying cause, managing edema and fluid overload with diuretics and salt restriction, and preventing complications like infection and thrombosis. Immunosuppressive therapy, typically with corticosteroids, is initiated for primary glomerular diseases, with adjustments based on response and specific histology.

Disclaimer: This article is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment. TruelyserMD does not replace clinical judgement.