Nephrotic syndrome

Background

• Increased permeability of glomerular capillary wall
  • Proteinuria, hypoproteinemia (albumin <3), edema, hyperlipidemia
• Life-threatening complications are infection and thromboembolic events

Clinical Features

• Edema (face, periphery)
• Shortness of breath, cough (pleural effusion, pulmonary edema)
• Oliguria

Complications

• Chronic high dose steroid adverse effects
• Pulmonary embolism
• Renal vein thrombosis
• Hypovolemic crisis
• Acute kidney injury
• Infection
• Cardiovascular issues (hyperlipidemia)
• Anemia
• Hypocalcemia
• Hypothyroidism
• Intussusception

Differential Diagnosis

• Primary nephrotic syndrome
  • Minimal-change, membranoproliferative
• Secondary nephrotic syndrome
  • SLE, HSP, SCD
• Classical characteristics/risk factors:
  • Minimal change disease - children, preceded by URI
  • Focal segmental glomerulosclerosis - Black patients, HIV/IVDA, specific anabolic steroids
  • Membranous nephropathy - Caucasian patients - primary etiology, HBV, HCV, SLE, gold, penicillamine, malignancy
  • Type 1 MPGN - HBV, HCV
  • Type 2 MPGN - ↓ C3

Periorbital swelling

Proptosis

• Normal IOP
  • Orbital cellulitis
  • Orbital pseudotumor
  • Orbital tumor
• Increased IOP
  • Retrobulbar abscess
  • Retrobulbar emphysema
  • Retrobulbar hemorrhage
  • Ocular compartment syndrome
  • Orbital tumor

No proptosis

• Periorbital cellulitis/erysipelas
• Dacryocystitis (lacrimal duct)
• Dacryocele/Dacryocystocele
• Dacryostenosis
• Dacryoadenitis (lacrimal gland)
• Allergic reaction
• Nephrotic Syndrome (pediatrics)

Lid Complications

• Blepharitis (crusts)
• Chalazion (meibomian gland)
• Stye (hordeolum) (eyelash folicle)

Other

• Subperiosteal abscess
• Orbital abscess
• Cavernous sinus thrombosis
• Conjunctivitis
• Contact dermatitis
• Herpes zoster
• Herpes simplex
• Sarcoidosis
• Granulomatosis with polyangiitis

Evaluation

• Urinalysis
  • Proteinuria > 3.5 g/24 hr, no hematuria
  • Spot urine protein : urine creatinine ratio of > 3 - 3.5mg/mg (300 - 350mg/mmol)
• CBC
• CMP
  • Pseudohyponatremia due to elevated triglycerides
  • Serum albumin < 25 g/L
• Lipid panel, with total cholesterol > 380mg/dL (10 mmol/L)
• ANA, C3, C4, viral hepatitis panel, HIV, SPEP, SIFE, UPEP, ANCA, free light chains, PLA2R
• CXR (only if suspect pleural effusion / pulmonary edema)
• Renal ultrasound
  • Only if suspect renal vein thrombosis - hematuria, flank pain, AKI

Management

• Give IV fluids if evidence of hypovolemic shock (even if edema is severe)
• Volume overload
  • Treat with furosemide 1-2mg/kg
  • May require correction of hypoalbuminemia first; 0.5-1gm/kg
• Steroids
  • Effective for minimal-change disease
  • Prednisone 2mg/kg/d in 2-3 divided doses x 6 weeks
• Low-salt diet
• Prophylactic anticoagulation for thromboembolic events not recommended, unless patient had previous thrombotic events

Disposition

Admit

• Severe edema
• Pulmonary effusion or respiratory symptoms
• Infection or thrombotic complications

Outpatient nephrology follow up

• Mild-moderate edema

References

• Kodner C. Nephrotic Syndrome in Adults: Diagnosis and Management. Am Fam Physician. 2009 Nov 15;80(10):1129-1134.