Pyelonephritis – Inflammation, Damage, and Management

Pyelonephritis (Kidney Infection):

• Usually caused by ascending infection from the ureters, often from a lower UTI like cystitis.
• Pus (exudate) fills the renal pelvis and calyces, leading to inflammation.

Locations involved:

• • Renal Pelvis and Calyces: Filled with pus (purulent exudate).
  • Renal Medulla: Center portion that may also become inflamed.

Complications:

• • Formation of abscesses or necrosis.
  • Obstruction of urine flow due to pus or swelling.
  • Hydronephrosis:  Excessive urine buildup in the renal pelvis due to obstruction.  Urine build-up in renal pelvis increases pressure, compresses blood vessels, leading to renal ischemia.
  • Urine pushing on nephrons damages kidney tissue.
  • Repeated infections cause scarring and loss of functional nephrons.

Signs and Symptoms:

• Pain with urination, frequency, nocturia.
• Lower back or flank pain: Dull, aching pain in the lumbar region.
• Fever: Elevated body temperature indicating infection.
• Urinalysis findings:
  • Cloudy urine indicating pyuria and/or proteinuria
  • Urinary casts composed of cellular debris in urine, indicating renal tubule damage.
  • Presence of blood, protein, and white blood cells signals tissue damage and infection.

Treatment:

• Antibiotics: To eliminate bacterial infection.
• Pain management: NSAIDs or acetaminophen.
• Drainage or surgery: In severe cases, to relieve obstruction and prevent kidney failure.

Summary:

Pyelonephritis is a serious kidney infection that can cause tissue damage, abscesses, and scarring, potentially leading to kidney failure if untreated. Signs include flank pain, fever, and abnormal urinalysis. Prompt antibiotics and management of obstructions are essential.