From the Guidelines
The treatment for acute interstitial nephritis primarily involves removing the offending agent and providing supportive care, with corticosteroids such as (methyl)prednisone 1 mg/kg being started in cases of suspected immune-related nephritis, as recommended by the most recent guidelines 1. The first step in managing acute interstitial nephritis is to identify and discontinue any potential offending agents, such as medications that may be causing the condition.
- Other causes of renal failure should be ruled out, and other nephrotoxic drugs should be stopped.
- Supportive care includes maintaining fluid and electrolyte balance, treating symptoms, and monitoring kidney function. For cases that don't improve with removal of the causative agent, corticosteroids are often prescribed, with the dose and duration depending on the severity of the condition, as outlined in recent clinical practice guidelines 1.
- In severe cases, such as stage 3 AKI, pulse methylprednisolone may be considered, and renal biopsy should be considered on a case-by-case basis to confirm the diagnosis 1. The rationale for corticosteroid therapy is to reduce the inflammatory response in the kidney interstitium, which is characterized by infiltration of inflammatory cells that damage the renal tubules. Most patients with drug-induced acute interstitial nephritis recover significant kidney function within weeks to months after appropriate treatment, though some may have residual kidney impairment, highlighting the importance of early diagnosis and treatment to prevent long-term kidney damage 1.
From the Research
Treatment Overview
The treatment for acute interstitial nephritis (AIN) primarily involves the discontinuation of the offending drug or agent causing the condition 2, 3, 4.
Role of Corticosteroids
- Corticosteroids, such as prednisolone, are often used in the treatment of AIN, especially when initiated early in the course of the disease 2, 3, 5, 4, 6.
- The benefits of corticosteroid therapy, although not universally proven, suggest a positive effect on patient outcomes, particularly in terms of improving renal function and reducing inflammation 2, 3, 4.
- Studies have shown that both oral and intravenous (IV) corticosteroids can be effective, with no significant difference in outcomes between the two forms of administration when used early in the treatment process 3.
Duration and Dosage of Corticosteroid Treatment
- Research indicates that the duration of corticosteroid treatment can vary, but high-dose treatment for more than 3 weeks or prolonged treatment beyond 8 weeks may not necessarily lead to better recovery of kidney function 5.
- The optimal dosage and duration of prednisolone treatment are subjects of ongoing research, with studies like the PRAISE trial aiming to evaluate the effectiveness of prednisolone in AIN 6.
Importance of Early Treatment
- Early recognition and treatment of AIN are crucial for preventing the progression to chronic kidney disease and for achieving the best possible recovery of kidney function 2, 5, 4.
- Delayed initiation of corticosteroid treatment has been associated with worse recovery of kidney function, highlighting the importance of prompt intervention 5.
Diagnostic Considerations
- While diagnostic tests such as urine eosinophils and renal gallium 67 scanning can provide suggestive evidence, renal biopsy remains the gold standard for diagnosing AIN 2, 4.
- The presence of interstitial fibrosis on kidney biopsy specimens has been associated with poorer outcomes, underscoring the need for timely and effective treatment 5.