INTRODUCTION

  • Glomerulonephritis occurring days to weeks after preceding infection
  • Often but not always group A Strep pharyngitis or impetigo
  • Often affects children aged 3-12 but can occur in teens and adults

PATHOPHYSIOLOGY

  • Antigen deposition in glomeruli → Interaction of antibodies in situ with antigens → Circulation of immune complexes → Deposition in glomeruli, with immune complex-mediated inflammation

CLINICAL MANIFESTATIONS

  • Spectrum of severity, from asymptomatic hematuria to florid renal failure and acute nephrotic syndrome
  • Gross hematuria is tea- or cola-colored; bright red blood indicates urinary tract bleeding
  • Microscopy will differentiate true hematuria from dark urine caused by hemoglobin, myoglobin, or hypochlorite
  • Seizure due to severe hypertension

MANAGEMENT

  • No specific treatment
  • Symptomatic treatment for:
    • Volume overload: Water restriction, diuretics
    • Hypertension: Antihypertensives (PO vs IV depending on severity and presence/absence of hypertensive urgency/emergency)
    • Avoid ACE inhibitors, which can cause hyperkalemia
    • Pulmonary edema: Diuretics, respiratory support
  • Indications for Dialysis
    • Life-threatening fluid overload refractory to therapy
    • Hyperkalemia > 6.5
    • Uremia with BUN > 89-100 mg/dL

PROGNOSIS

  • Prognosis is generally good
  • Hematuria usually resolves within 3-6 months; proteinuria takes longer to resolve
  • If C3 levels do not normalize by 10 weeks or serum creatinine remains elevated or worsens, other causes of hematuria should be considered
  • Long-term complications are rare but include hypertension or renal insufficiency years or decades after initial illness