Retroperitoneal fibrosis presenting as spontaneously reversible renal failure

Area of Science:

• Nephrology
• Urology
• Internal Medicine

Background:

• Retroperitoneal fibrosis can lead to obstructive uropathy and acute kidney injury.
• Distinguishing obstructive uropathy from other causes of renal failure is clinically important.

Observation:

• Three patients with severe oliguric renal failure due to retroperitoneal fibrosis presented with findings suggestive of obstructive uropathy.
• Clinical clues included back/abdominal pain, anemia, and specific metabolic acidosis.
• Inappropriately high urine pH and absence of casts were noted.

Findings:

• All patients experienced spontaneous diuresis and rapid renal function recovery within one day.
• This clinical course mimicked acute tubular necrosis but was ultimately due to obstruction.

Implications:

• Highlights the importance of considering and ruling out urinary tract obstruction in unexplained renal failure.
• Adds retroperitoneal fibrosis to the spectrum of conditions causing reversible renal failure.
• Emphasizes that obstructive uropathy should be suspected even when renal failure presentation resembles other acute kidney injuries.