What is the appropriate management of acute cortical necrosis?

Management of Acute Cortical Necrosis

Immediate Supportive Care

The cornerstone of acute cortical necrosis (ACN) management is aggressive supportive care with early dialysis initiation, hemodynamic stabilization, and treatment of the underlying precipitating cause. 1

Hemodynamic Stabilization and Fluid Management

• Restore hemodynamic stability immediately through aggressive fluid resuscitation with crystalloids in cases of hypovolemia or decreased effective arterial blood volume. 1, 2
• Monitor volume status carefully with daily urine output measurements, as oliguria is associated with poor prognosis. 3
• In patients with volume depletion who do not respond to initial crystalloid resuscitation, consider 20% albumin solution at 1 g/kg (maximum 100 g) for two consecutive days. 3

Nephrotoxin Elimination

• Discontinue all nephrotoxic medications immediately, including NSAIDs, aminoglycosides, ACE inhibitors, ARBs, and contrast agents. 3
• Withdraw diuretics after ACN diagnosis is confirmed. 3
• Avoid administering additional nephrotoxic agents during the acute phase. 3

Infection Control

• Screen for and treat infections aggressively, as septicemia is a common precipitating factor, particularly in obstetric-related ACN. 3, 4
• Do not use prophylactic antibiotics, as their efficacy is unproven. 3
• Avoid prophylactic bladder catheterization to minimize infection risk. 3

Renal Replacement Therapy

Initiate hemodialysis early based on clinical indications rather than waiting for specific biochemical thresholds. 1, 2

Indications for Dialysis

• Severe or refractory hyperkalemia 1, 3
• Metabolic acidosis unresponsive to medical management 1
• Volume overload unresponsive to diuretics 1
• Uremic symptoms (encephalopathy, pericarditis) 1
• Anuria or severe oliguria (dialysis dependence >21 days is common in ACN) 4

Dialysis Modality Selection

• Continuous veno-venous hemofiltration (CVVH) is preferred over intermittent hemodialysis in hemodynamically unstable patients, as it may increase renal blood flow and improve renal function when combined with positive inotropic agents. 3
• Intermittent hemodialysis is appropriate for hemodynamically stable patients. 2
• Most patients with ACN require prolonged dialysis support (often 3+ years), though partial recovery is possible in select cases. 2, 5

Diagnostic Confirmation

Imaging

• MRI is the preferred non-invasive diagnostic method, showing characteristic low T2 signal rim at the corticomedullary junction and absence of cortical enhancement following contrast administration. 1
• Contrast-enhanced CT demonstrates hypoattenuation of cortex compared to medulla, with contrasted medulla and thin layer of subcapsular cortex but without bilateral cortical enhancement. 6, 7
• Ultrasound contrast media are not nephrotoxic and can diagnose acute cortical necrosis in native kidneys. 8

Histopathologic Confirmation

• Percutaneous renal biopsy performed at 4 weeks of illness can confirm diffuse or patchy cortical necrosis. 4, 6
• Histology shows coagulative necrosis of glomeruli (ranging from 25% to 100% involvement), with interstitial lymphocytic infiltration and mild edema. 4

Treatment of Underlying Causes

Obstetric Complications

• ACN remains most commonly associated with obstetric complications (postpartum hemorrhage, placental abruption, septicemia following delivery). 4
• Better monitoring of pregnancies and prompt management of obstetric emergencies are essential preventive measures. 4

Thrombophilia and Hypercoagulable States

• In cases secondary to hyperhomocysteinemia or antiphospholipid syndrome, anticoagulate with low-molecular-weight heparin. 5, 7
• Treat hyperhomocysteinemia with folate supplementation and vitamin B12 injections, which may facilitate partial renal recovery. 5
• Check thrombophilia screen including serum homocysteine, antiphospholipid antibodies, and lupus anticoagulant. 5, 7

Pancreatitis-Related ACN

• Manage acute pancreatitis complications (acute necrotic collections, pleural effusion) conservatively while providing renal support. 6
• This is an extremely rare cause with less than 10 reported cases. 6

Long-Term Management and Monitoring

Chronic Kidney Disease Surveillance

• Regular monitoring of renal function with serum creatinine and estimated GFR is mandatory, as most patients progress to end-stage renal disease. 1
• Monitor serum creatinine daily during the acute phase to assess AKI stage. 3
• Evaluate patients at 3 months post-recovery for new onset or worsening chronic kidney disease, with long-term follow-up extending 12-74 months. 3

Complications Management

• Manage anemia and mineral bone disorder according to chronic kidney disease protocols. 1
• Control blood pressure aggressively to prevent further kidney damage. 1
• Provide enteral nutrition preferentially over parenteral (20-30 kcal/kg/day; protein 1.0-1.5 g/kg/day if on renal replacement therapy). 3
• Monitor and correct electrolyte disturbances, particularly hypocalcemia. 3

Transplant Evaluation

• Evaluate patients for renal transplantation when there is no improvement in renal function after prolonged dialysis support (typically after several months to years of dialysis dependence). 6

Critical Pitfalls to Avoid

• Do not delay dialysis initiation in patients with ACN, as early renal replacement therapy is essential for survival despite the poor prognosis for renal recovery. 2, 4
• Do not assume complete irreversibility—while most cases progress to end-stage renal disease, partial recovery with dialysis independence has been documented in select cases, particularly when underlying causes (hyperhomocysteinemia, thrombophilia) are identified and treated. 2, 5
• Do not overlook thrombophilia screening in non-obstetric ACN cases, as anticoagulation and specific treatments may improve outcomes. 5, 7
• Recognize that ACN carries a mortality rate of approximately 37.1% in hospitalized patients, emphasizing the need for intensive monitoring and aggressive supportive care. 3