[Acute renal failure--"a well meant present from a friend"]

Area of Science:

• Nephrology
• Pharmacology
• Toxicology

Background:

• Acute allergic interstitial nephritis (AIN) is a rare adverse drug reaction.
• Non-steroidal anti-inflammatory drugs (NSAID) are a known cause of AIN.

Observation:

• A 70-year-old woman experienced recurrent acute renal failure.
• The first episode of AIN followed oral mefenaminic acid.
• A second AIN episode occurred after transdermal diclofenac application.

Findings:

• This case demonstrates cross-reactivity between different NSAIDs.
• Transdermal NSAID application can lead to systemic adverse events.
• Patients and physicians may overlook topical medications as a cause of systemic effects.

Implications:

• Clinicians should consider NSAID cross-reactivity in AIN cases.
• Inquiring about all medication forms, including topical, is crucial for diagnosis.
• Awareness of transdermal drug risks is important for patient safety.