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Nephritic Syndrome

Topic updated on 08/22/17 9:25pm

Snapshot
  • A 26-year-old man presents with hematuria, periorbital edema, and jaundice. He has a medical history of opioid use disorder with prior hospitalizations for heroin overdose. He is on methadone but is non-adherent. His blood pressure is 155/102 mmHg. Physical examination is significant for scleral icterus, hepatomegaly, and palpable purpura. Serology shows decreased C3 and C4 levels and elevated anti-hepatitis C antibodies. Urinalysis demostrates dysmorphic red blood cells and red blood cell casts.  (Membranoproliferative glomerulonephritis)
Introduction
  • Clinical definition
    • renal disease secondary to an inflammatory process injuring the glomerulus
      • this results in damage involving the
        • basement membrane
        • capillary endothelium
        • mesangium
  • Presentation
    • symptoms
      • hypertension
      • hematuria
      • oliguria
      • headache
    • physical exam
      • edema
        • can be peripheral and/or periorbital
  • Diagnosis
    • studies
      • complete blood cell count
        • anemia may be noted
      • azotemia
      • complement levels
        • C3, C4, and CH50 should be obtained
      • urinalysis
        • dysmorphic red blood cells (RBCs)
          • suggests hematuria is of glomerular origin
        • RBC casts
        • subnephrotic range proteinuria (< 3.5 g/day)
          • if the nephritic syndrome is severe enough it can lead to nephrotic range proteinuria (> 3.5 g/day)
    • renal biopsy
      • may be necessary to arrive to a definitive diagnosis and to determine prognosis
 
Nephritic Syndrome
Type
Pathophysiology
Renal Biopsy
Diagnostic Studies and Treatment
Acute poststreptococcal glomerulonephritis 
  • Glomerulonephritis secondary to nephritogenic strains of streptococcus
    • type III hypersensitivity reaction
  • Light microscopy
    • glomerular hypercellularity 
      • e.g., polymorphonuclear leukocytes 
  • Immunofluoresence
    • diffuse granular pattern on glomerular capillary and mesangium
      • deposition of IgG, IgM, and C3 
  • Electron microscopy
    • electron-dense, glomerular subepithelial immune-complex deposits ("humps")
  • Streptococcus titers and serologies are positive
    • e.g., ASO levels 
  • ↓ serum C3 levels
  • Typically self-resolves
Rapidly progressive glomerulonephritis
  •  Goodpasture syndrome  
    • type II hypersensitivity
    • anti-GBM antibodies against α3-chain of collagen type IV 
      • antibodies to the alveolar basement membrane result in hemoptysis and lung disease
  • Pauci-immune processes
    • granulomatosis with polyangiitis
    • microscopic polyangiitis
  • Light microscopy and immunofluoresence
    • crescent-shaped deposition of fibrin, C3b, glomerular parietal cells, monocytes, and macrophages
  • Granulomatosis with polyangiitis
    • PR3-ANCA/c-ANCA positive 
  • Microscopic polyangiitis
    • MPO-ANCA/p-ANCA
  • Corticosteroids and cyclophosphamide
IgA nephropathy (Berger disease)
  • IgA immune-complex deposition in glomerular mesangial cells that results in its proliferation 
    • patients present with hematuria and upper respiratory tract or gastrointenstinal infection
  • Light microscopy
    • mesangial proliferation
  • Immunofluoresence
    • IgA immune-complex deposition in the mesangium
  • ACE inhibitor or ARB for proteinuria and hypertension
Alport syndrome
  • Collagen type IV mutation that results in an abnormal basement membrane
    • more commonly an X-linked genetic disorder
    • characterized by
      • renal involvement
      • ocular involvement
      • sensorineural hearing loss
  • Electron microscopy
    • glomerular basement membrane lamellation
  • No curative treatment
Membranoproliferative glomerulonephritis (MPGN)
  • Immune-complex and/or complement protein deposition in the mesangium and subendothelium of the capillaries
    • this results in proliferation of the mesangium and remodeling of the capillary wall
    • may be secondary to
      • hepatitis C virus
      • hepatitis B virus
      • C3 nephritic factor
        • MPGN type II
  • Light microscopy
    • mesangial proliferation and thickening of the capillary wall
  • Immunofluoresence
    • "tram-track" appearance
  • ↓ serum C3 and C4 levels
  • Treat underlying disease in secondary causes
    • e.g., control of hepatitis C virus infection
 


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Qbank (1 Questions)

TAG
(M2.RL.167) A 12-year-old male is brought to the clinic by is mother for what she describes as a "swollen face." His recent medical history is significant for impetigo two weeks ago. On physical exam he has elevated blood pressure for his age. What is the most appropriate next step in the management? Topic Review Topic

1. Urinalysis
2. Antistreptolysin O titers
3. Renal ultrasound
4. Abdominal CT
5. Empiric antibiotics

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