Sarcoid granulomatous nephritis occurring as isolated renal failure

Area of Science:

• Nephrology
• Immunology
• Pathology

Background:

• Sarcoidosis is a multisystem inflammatory disease characterized by noncaseating granulomas.
• Renal involvement in sarcoidosis is common but often presents without specific renal symptoms.
• Clinically isolated renal failure can be a rare presenting manifestation of sarcoidosis.

Observation:

• A patient presented with unexplained renal failure.
• Renal biopsy revealed noncaseating epithelioid granulomas, indicative of granulomatous nephritis.
• Initial clinical presentation lacked features suggestive of sarcoidosis.

Findings:

• Steroid therapy led to rapid improvement in uremic symptoms and renal function.
• Diagnosis of sarcoidosis was confirmed by mediastinal lymph node biopsy showing identical granulomas.
• Associated findings included leukopenia and delayed cellular immunity, supporting sarcoidosis.

Implications:

• Renal biopsy is essential for diagnosing isolated renal failure due to sarcoid nephritis.
• Prompt diagnosis and steroid treatment can effectively manage sarcoid nephritis.
• This case highlights sarcoidosis as a treatable cause of isolated renal failure.