Can a patient with a positive Urinary Tract Infection (UTI) be referred to a nephrologist?

Nephrology Referral for Urinary Tract Infection

A simple urinary tract infection (UTI) alone does not warrant nephrology referral. However, specific complications or underlying kidney disease associated with UTI may require nephrology consultation.

When Nephrology Referral is NOT Indicated

• Uncomplicated UTI (cystitis or pyelonephritis) in otherwise healthy patients does not require nephrology referral 1, 2
• Simple bladder infections presenting with dysuria, frequency, urgency, and suprapubic pain are managed by primary care or emergency medicine 3, 2
• Acute pyelonephritis with fever, flank pain, and systemic symptoms typically requires urology consultation if imaging shows obstruction, but not routine nephrology referral 3, 2

When Nephrology Referral IS Indicated

Kidney Function Impairment

• Refer to nephrology if eGFR <30 mL/min/1.73 m² in the setting of UTI 4, 5
• Acute kidney injury (AKI) with creatinine increase ≥50% from baseline that persists after UTI treatment requires nephrology evaluation 4, 5
• Elevated serum creatinine that does not resolve after appropriate UTI treatment warrants nephrology consultation 4

Proteinuria or Hematuria Beyond UTI

• Persistent proteinuria >1 g/day (ACR ≥60 mg/mmol) after UTI resolution requires nephrology referral 5
• Persistent microscopic hematuria (>20 RBCs per high power field) after negative urologic workup and UTI treatment 5, 6
• Presence of urinary red cell casts suggests glomerulonephritis rather than simple UTI and mandates nephrology referral 5

Recurrent or Complicated UTI with Kidney Concerns

• Recurrent UTIs in patients with known chronic kidney disease (CKD) stage 3b or worse (eGFR <45 mL/min/1.73 m²) 4, 5
• UTI in patients with rapidly declining kidney function (>5 mL/min/1.73 m² per year decline) 5
• Suspected immune-mediated nephritis (sterile pyuria with eosinophilia) presenting as "UTI" requires nephrology consultation 4

Structural Abnormalities Affecting Kidney Function

• Hydronephrosis with declining kidney function or bilateral obstruction requires both urology and nephrology involvement 6
• Recurrent nephrolithiasis with UTI and evidence of kidney damage 5, 6

Special Populations

• Pediatric patients with UTI and urinary tract dilation (UTD P2-3) or ureteral dilation ≥7 mm should be referred to nephrology and/or urology 4
• Neonates with UTI and elevated creatinine require nephrology consultation 4
• Diabetic patients with UTI and albuminuria or eGFR <30 mL/min/1.73 m² 4, 5

Common Pitfalls to Avoid

• Do not assume elevated creatinine during acute UTI/pyelonephritis is always reversible—if creatinine remains elevated >50% above baseline after 1 week of appropriate antibiotics, consider nephrology referral 4, 5
• Do not attribute persistent hematuria solely to UTI—after negative urine culture, persistent hematuria requires urologic evaluation first, then nephrology if urologic causes are excluded 4, 6
• Do not confuse asymptomatic bacteriuria with UTI requiring treatment—asymptomatic bacteriuria does not require antibiotics (except in pregnancy) and does not warrant nephrology referral 1, 7
• Anticoagulation or antiplatelet therapy does not explain hematuria—these patients still require full evaluation if hematuria persists 4

Practical Algorithm

1. Treat the UTI appropriately with antibiotics based on local resistance patterns 2, 7
2. Measure baseline kidney function (creatinine, eGFR) if not recently available 4
3. Reassess kidney function 1 week after treatment completion 4
4. If creatinine normalizes and no proteinuria/hematuria persists: No nephrology referral needed 5
5. If eGFR <30 mL/min/1.73 m², persistent AKI, proteinuria >1 g/day, or unexplained hematuria: Refer to nephrology 4, 5
6. For pediatric UTI with structural abnormalities: Coordinate nephrology and urology referral 4