Abstract: FR-PO0467
Granulomatous Acute Interstitial Nephritis Revealing Long-Misdiagnosed Sarcoidosis as Tuberculosis
Session Information
- AKI: Case Reports - TMA, Vasculitis, Immune-Mediated Injury, and Systemic Disease
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Ding, Ning, Center for Kidney Diseases, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
- Zhang, Jie, Center for Kidney Diseases, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
- Qiu, Yumei, Center for Kidney Diseases, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
- Fang, Yi, Center for Kidney Diseases, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
- He, Weichun, Center for Kidney Diseases, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
Introduction
Sarcoidosis is a systemic granulomatous disease that frequently involves lung but rarely affects kidney. Sarcoidosis shares similarities with tuberculosis (TB) in clinical and pulmonary imaging features, often leading to misdiagnosis, especially when differentiating it from culture-negative TB. Granulomatous acute interstitial nephritis (GAIN), a rare renal manifestation of sarcoidosis that can progress to acute kidney injury (AKI), posing a diagnostic challenge.
Case Description
A 78-year-old male was admitted due to AKI requiring dialysis. Urinalysis suggested tubulointerstitial injury, whereas serological tests showed hypercalcemia, low levels of 25-hydroxyvitamin D and parathyroid hormone. Computed Tomography revealed lymphadenopathy in mediastinum and bilateral hila. Renal biopsy exhibited non-caseating GAIN. Carefully review medical history revealed that he was diagnosed with culture-negative TB 3 years ago due to fever and pulmonary imaging, with a mild elevation in serum creatinine (SCr). He was placed on anti-TB therapy with intermittent glucocorticoid (GC) for symptomatic relief. During the course, SCr elevation and pulmonary imaging fluctuated with GC use: improved on GC, relapsed on dose reduction/withdrawal, consistent with the therapeutic response of sarcoidosis to GC. Then, with the elevated level of serum angiotensin-converting enzyme (ACE), a diagnosis of sarcoidosis was established. Subsequent administration of GC resulted in renal function improvement, with successful discontinuation of dialysis. Serum calcium and ACE levels returned to normal, and pulmonary imaging improved.
Discussion
Early identification of sarcoidosis-related GAIN and timely treatment with GC could effectively reverse renal function. This case underscores the crucial role of multisystem assessment and renal biopsy in the diagnosis of difficult and rare kidney diseases.
Figure. pulmonary imaging (A) and GAIN (B) in sarcoidosis