Urology: Upper UTI - Pyelonephritis

Question 1

Describe the pathophysiology of pyelonephritis

Answer 1

Bacterial invasion of the renal parenchyma

Bacteria usually reach the kidney by ascending from the lower urinary tract or the blood stream

Question 2

What is the aetiology of pyelonephritis?

Answer 2

E.coli = 70-95%

Klebsiella spp = 1-2%

Coag-ve staphylococci = 5-10%

Question 3

What are the signs and symptoms of pyelonephritis?

Answer 3

Fever

Nausea

Vomiting

Costovertebral angle pain = may be mild, moderate, or severe; flank or costovertebral angle tenderness is most commonly unilateral over the involved kidney, although bilateral discomfort may be present

Gross haematuria

Elderly = mental state change

Question 4

Outline how pyelonephritis should be investigated?

Answer 4

Dipstick leukocyte esterase test (LET) = Helps to screen for pyuria

Nitrite production test (NPT) = To screen for bacteriuria

Examination for haematuria (gross and microscopic) and proteinuria

Urine culture

CT = identify alterations in perfusion, contrast excretion, infection, haemorrhage, masses, obstruction

MRI = detect renal infection, masses, obstruction

US = screen for obstruction

Question 5

How should pyelonephritis be managed?

Answer 5

IV fluid to maintain hydration

IV Abx = until significant symptomatic improvement then oral
- GP = 7 day co-amoxiclav

Surgery = renal abscess, renal necrosis

Calculi-related urinary tract infection (UTI) = extracorporeal shockwave lithotripsy (ESWL)

Question 6

What are the possible complications from pyelonephritis?

Answer 6

Renal scaring

Acute renal failure = children, health adults, pregnant women

Sepsis