Pyelonephritis

 

a) Pathophysiology: typically ascending infection form lower urinary tract, caused by enteric gram negative rods

 

b) Risk factors: frequency of intercourse, UTI within past 12 months, diabetes, stress incontinence, new sexual partner, use of spermicide

 

c) Diagnosis:

      - Clinical: common sx include fever, nausea/vomiting, abdominal/flank/pelvic pain

      - UTI may show WBC casts, indicating that source of infection is upper urinary tract

      - Should also screen for pregnancy, as this makes infection complicated

      - Imaging: not required routinely, but may have a role in following settings:

         - Failure to respond to appropriate therapy after 72h (raises concern for abscess)

         - Renal colic (to assess for obstruction)

         - Diabetes

         - Men (to evalute for anatomic abnormalities)

         - Virulent organism

         - Relapse

         - Sepsis

 

d) Treatment:

      - Targeted at enteric GNRs (3rd generation cephalosporins, fluoroquinolones, aztrenoam)

      - Oral and intravenous fluoroquinolones have been shown to have similar efficacy, thus all patients do not require admission

      - Indications for admission:

          - High fever

          - Septic physiology

          - Inability to take POs

          - Pregnancy

      - Duration of therapy: 5-7 days for uncomplicated infection, 14 days if bacteremia

 

e) Complications:

      - Abscess: renal corticomedullary, perinephric

      - Emphysematous pyelonephritis

      - Renal papillary necrosis

 

(Christopher Woo MD, 8/14/10)