Introduction:

Acute interstitial nephritis (AIN) is an inflammatory condition affecting the renal interstitium, often caused by medications, infections, or autoimmune diseases. This article provides a comprehensive overview of AIN, including its causes, symptoms, diagnosis, treatment, and management strategies.

Causes of Acute Interstitial Nephritis:

AIN can be triggered by various factors, including:

• Medications: Antibiotics (e.g., penicillins, cephalosporins), proton pump inhibitors, nonsteroidal anti-inflammatory drugs (NSAIDs), diuretics, and certain antiviral medications.
• Infections: Viral infections (e.g., hepatitis, HIV), bacterial infections (e.g., streptococcal, Legionella), and parasitic infections (e.g., toxoplasmosis).
• Autoimmune Disorders: Systemic lupus erythematosus (SLE), sarcoidosis, and IgG4-related disease.
• Allergic Reactions: Hypersensitivity reactions to medications or environmental triggers.

Symptoms of Acute Interstitial Nephritis:

AIN may manifest with the following symptoms:

• Acute Kidney Injury (AKI): Decreased urine output, fluid retention, and electrolyte imbalances.
• Systemic Symptoms: Fever, fatigue, malaise, nausea, vomiting, and weight loss.
• Urinary Abnormalities: Hematuria (blood in urine), proteinuria (protein in urine), and leukocyturia (white blood cells in urine).

Diagnosis of Acute Interstitial Nephritis:

Diagnosing AIN involves the following steps:

• Medical History: Review of medication use, recent infections, autoimmune diseases, and allergic reactions.
• Physical Examination: Assessment for signs of fluid overload, edema, hypertension, and skin rashes.
• Laboratory Tests: Urinalysis to detect abnormalities such as hematuria, proteinuria, and leukocyturia. Blood tests to assess renal function (serum creatinine, blood urea nitrogen).
• Renal Biopsy: Definitive diagnosis often requires a renal biopsy to evaluate interstitial inflammation and exclude other renal pathologies.

Treatment of Acute Interstitial Nephritis:

Management of AIN involves the following approaches:

• Discontinuation of Causative Agents: Prompt cessation of implicated medications or treatment of underlying infections.
• Supportive Care: Intravenous fluids to maintain hydration and electrolyte balance. Correction of acid-base disturbances and management of complications such as hypertension.
• Corticosteroids: In severe or persistent cases of AIN, systemic corticosteroids (e.g., prednisone) may be prescribed to suppress inflammation and prevent progression to chronic kidney disease (CKD).
• Immunosuppressive Therapy: In cases associated with autoimmune diseases or refractory AIN, immunosuppressive agents such as cyclophosphamide or mycophenolate mofetil may be considered under specialist guidance.

Management Strategies for Acute Interstitial Nephritis:

• Regular Monitoring: Close monitoring of renal function through serial measurements of serum creatinine and urine output.
• Patient Education: Educate patients about the importance of medication adherence, avoidance of nephrotoxic agents, and seeking medical attention for worsening symptoms.
• Follow-up Care: Schedule regular follow-up appointments to assess renal function, monitor for relapse, and adjust treatment as necessary.
• Collaboration with Specialists: Collaborate with nephrologists, infectious disease specialists, and rheumatologists for comprehensive management, especially in complex or refractory cases.

Conclusion:

Acute interstitial nephritis is a potentially reversible cause of acute kidney injury characterized by interstitial inflammation. Timely recognition of causative factors, prompt discontinuation of offending agents, and appropriate treatment strategies are essential for optimizing outcomes and preventing progression to chronic kidney disease.

Hashtags: #AcuteInterstitialNephritis #AIN #KidneyInflammation #MedicationReactions