Etiology

  • Ascending infection: E. coli (most common)

  • Proteus, Klebsiella

  • Risk factors: female sex, vesicoureteral reflux, obstruction, catheters

Pathogenesis

  • Bacterial invasion of renal pelvis → spread to renal parenchyma

  • Neutrophilic infiltration → abscess formation in severe cases

Clinical Features

  • Fever, chills

  • Flank pain

  • Nausea, vomiting

  • Dysuria, frequency

  • CVA tenderness

  • Pyuria, WBC casts

Treatment

  • Oral antibiotics (fluoroquinolones, TMP-SMX) for uncomplicated cases

  • IV antibiotics for severe/complicated cases

  • Treat underlying obstruction if present