Management and Outcomes of Glomerulonephritis and Acute Kidney Injury in Critically Ill Patients

• Acute Kidney Injury (AKI) in Critically Ill Patients:
  • Over half of critically ill patients develop AKI, with nearly 5% requiring renal replacement therapy (RRT).
  • Mortality for severe AKI requiring RRT can be as high as 70%, and up to 30% of surviving patients remain dialysis dependent.
• Causes and Presentation of Glomerulonephritis (GN):
  • GN may cause nephritic syndrome characterized by hematuria, proteinuria, AKI, edema, and hypertension.
  • Common manifestations include dysmorphic red blood cells in urine sediment, elevated proteinuria, and leukocyturia with or without white blood cell casts.
• Diagnosis and Prognosis of GN:
  • Kidney biopsy is critical for diagnosing the type of GN and assessing acute versus chronic disease, guiding treatment and informing prognosis.
  • Rapidly progressive glomerulonephritis (RPGN) presents with rapidly declining renal function, progressive oliguria, hematuria, proteinuria, and hypertension.
• Specific Diseases Associated with RPGN:
  • The most common causes of RPGN in adults are pauci-immune GN, lupus nephritis, and anti-GBM disease.
  • Treatment for RPGN involves early intervention and therapy to prevent progression to chronic kidney disease.
• Pulmonary-Renal Syndrome and Associated Diseases:
  • Pulmonary-renal syndrome is a medical emergency requiring early aggressive treatment.
  • ANCA-associated vasculitis and anti-GBM disease are the most common causes of pulmonary-renal syndrome.
• Treatment and Prognosis of Pauci-Immune Necrotizing GN:
  • Pauci-immune necrotizing GN may present as a systemic vasculitis, pulmonary-renal syndrome, or renal-limited disease.
  • Advances in treatment have led to improved patient outcomes, with 80%–85% of patients achieving remission with effective immunosuppressive strategies.
• Management of Severe Disease Complications:
  • Poor prognostic indicators for patient and renal survival include the presence of DAH, severe kidney dysfunction at diagnosis, and a high degree of glomerular injury and tubulointerstitial fibrosis on biopsy.
  • Severe renal disease patients have a greater likelihood of renal recovery when treated with plasma exchange.
• ANCA-associated Vasculitides:
  • 80%–90% of patients achieve remission.
  • Treatment resistance is more common in females, African Americans, and patients with severe renal disease.
• Anti-GBM Disease:
  • Untreated disease is highly fatal, and death is usually caused by pulmonary hemorrhage or renal failure.
  • In patients with renal and pulmonary involvement, plasma exchange is crucial for rapid clearance of anti-GBM antibodies.
• Lupus Nephritis:
  • Lupus nephritis occurs in 50%–60% of patients with SLE during the first 10 years of disease.
  • Renal biopsy is critical for diagnosis, prognosis, and guiding treatment.
• Severe Forms of Lupus Nephritis:
  • Proliferative lesions in class III/IV lupus nephritis have poor renal survival without aggressive treatment.
  • Plasma exchange did not show additional benefit in a clinical trial using standard glucocorticoid plus cyclophosphamide for proliferative lupus nephritis induction therapy.
• Management of Lupus Nephritis:
  • About 5%–10% of patients who require RRT initially recover enough kidney function to become dialysis independent after treatment.
  • MMF is the preferred agent for maintenance therapy.
• Poor Prognostic Indicators in Lupus Nephritis:
  • Male gender, African American race, severe hypertension, APS, and delayed immunosuppressive therapy are poor prognostic indicators at the beginning of treatment.
  • Failure to achieve remission at 6 months and uncontrolled hypertension are poor prognostic indicators after induction treatment.
• Relapse and Monitoring in Lupus Nephritis:
  • About one-third to half of patients will have a relapse of the disease.
  • All patients with a history of lupus nephritis should be carefully monitored for recurrence of the disease.
• Infection-associated GN:
  • Bacterial, viral, fungal, protozoal, and helminth infections may result in infection-associated GN.
  • Poststreptococcal glomerulonephritis remains the most common cause of acute nephritic syndrome in the pediatric population, especially in developing countries.
• Poststreptococcal Glomerulonephritis (PSGN):
  • Usually resolves in 7–14 days with excellent prognosis in children
  • About 10%–20% of children have persistent urinary abnormalities
• Infection-Related Glomerulonephritis (IRGN) in Adults:
  • Worse outcomes for adults in industrialized world, particularly with underlying chronic conditions
  • Treatment involves supportive care, diuretics, and eradication of infection
• IgA Nephropathy (IgAN):
  • Prognosis highly variable with 15%–25% progressing to ESRD at 10 years after diagnosis
  • Treatment includes aggressive hypertension management and consideration of corticosteroids or immunosuppressive agents in select cases
• IgA Vasculitis (IgAV):
  • Systemic disease with distinct rash, arthritis, gastrointestinal involvement, and IgAN
  • Renal recovery better in children; poor prognostic indicators in adults include renal dysfunction and significant proteinuria at presentation