Pyelonephritis refers to a upper urinary tract infection, versus "cystitis" seen in the lower urinary tract. The most common organism is E. Coli, followed by Staph. saprophyticus.

Si/Sx

• flank pain/CVA tenderness
• nausea, vomiting
• fever (> 38C)
• frequency, dysuria
• hematuria
• pyuria

Dx

Urinalysis (“UA”) signs indicative of pyelonephritis include:

• many WBC
• nitrite + (nitrite indicates organisms able to reduce nitrate to nitrite, and does not include certain organisms such as enterococci)
• esterase +
• white cell casts: rare, indicate a renal source for pyuria
• *note: the presence of epithelial cells indicates that the specimen was contaminated by contents outside the urinary tract. Epithelial cells are not found in the urinary tract.

A pelvic exam should be completed, as pelvic inflammatory disease is often confused with pyelonephritis. A pregnancy test should also be completed if LMP is unknown. Urine culture is also indicated, as resistance to empiric therapy may have serious sequelae.

Sequelae

• Obstruction
• Abscess
• Urosepsis
• Xanthogranulomatous Pyelonephritis

Tx
Empiric antibiotic treatment:

• Aminoglycosides – gentamicin, in combination with ampicillin if gram positive organisms (i.e. enterococcus)
• Fluoroquinolones – i.e. ciprofloxacin, 500mg PO BID or levofloxacin 500 mg PO daily (good renal concentration, relatively low resistance)
• Bactrim – has increasing resistance
• Complicated pyelonephritis should be treated with broad-spectrum antibiotics, based on culture results if possible.

Patients who are unable to eat or drink fluids, pregnant, remain sick after 48 to 72 hours, are likely to be uncompliant, or have severe illness should be admitted to the hospital for care. These patients can be treated with ceftriaxone or an aminoglycoside (gentamicin).