Abstract
BACKGROUND: Acute kidney injury (AKI) due to interstitial nephritis is a known condition primarily attributed to various medications. While medication-induced interstitial nephritis is common, occurrences due to non-pharmacological factors are rare. This report presents a case of severe AKI triggered by intratubular oxalate crystal deposition, leading to interstitial nephritis. The aim is to outline the case and its management, emphasizing the significance of recognizing uncommon causes of interstitial nephritis. CASE SUMMARY: A 71-year-old female presented with stroke-like symptoms, including weakness, speech difficulties, and cognitive impairment. Chronic hypertension had been managed with hydrochlorothiazide (HCTZ) for over two decades. Upon admission, severe hypokalemia and AKI were noted, prompting discontinuation of HCTZ and initiation of prednisolone for acute interstitial nephritis. Further investigations, including kidney biopsy, confirmed severe acute interstitial nephritis with oxalate crystal deposits as the underlying cause. Despite treatment, initial renal function showed minimal improvement. However, with prednisolone therapy and supportive measures, her condition gradually improved, highlighting the importance of comprehensive management. CONCLUSION: This case underscores the importance of a thorough diagnostic approach in identifying and addressing uncommon causes of interstitial nephritis. The occurrence of interstitial nephritis due to oxalate crystal deposition, especially without typical risk factors, emphasizes the need for vigilance in clinical practice.