Pyelonephritis Flashcards
What is pyelonephritis?
Inflammation of the kidney parenchyma and renal pelvis, typically due to bacterial infection
What is uncomplicated vs complicatd pyelonephritis?
Uncomplicated- when present in a structurally or functionally normal urinary tract in a non-immunocompromised host
Opposite true for complicated
How can bacteria reach the kidney?
Ascending the lower urinary tract
Directly from the blood stream (speticaemia or infective endocarditis)
Rarley via lymphatics (in cases of reteroperitoneal abscesses)
What is the most common organism to cause pyelonephritis, and give some other examples?
Most common is E.coli
Others include staphylococcus saprophyticus
Enterococcus faecalis, klebsiella, proteus, staphylococcus aureus and pseudomonas (catheter)
What are the risk factors for pyelonephritis?
Reduced antegrade flow of urine
Promoting reterograde ascent of bacteria - female gender, catheter, ureteric stents, structural abnormalites
Immunocompromised/infection
Promoting bacteril colonistaion - renal calculi, sexual intercourse, osestrogen dependant (menopause)
What is the classic triad for pyelonephritis?
Fever, loin pain, N/V typically developing over 24-48hrs
What othe signs and symptoms may a pt with pyelonephritis have?
Co-existing UTI
Visible/ non-visible haemturia
Look unwell and pyrexial
Costovertebral angle tenderness
What are the differential diagnosis for pyelonephritis?
AAA - most important to rule out
Renal calculi, PID, acute Cholecystitis, ectopic pregnancy, diverticulitis or lower lobe pneumonia
What investigations could be done for pyelonephritis?
Urinalysis + urine culture
Routine bloods
Renal US - look for obstructions as infected and obstructed renal system = emergency
Non-contrast CT imaging (CT KUB) - if obstruction suspected
What is the initial management of pyelonephritis?
Empirical antibiotics and IV fluids as appropriate, analgesia and anti-emetics and the tailor antibiotics to culture results
Uncomplicated cases often treated in community
When should admission be consider in pyelonephritis?
Clinically unstable
Significant dehydration
Co-morbidities - DM, renal transplant graft, immunocompromised
What may severe or non-responding cases of pyelonephritis require?
Catheter and high-dependency unit monitoring - can become rapidly unwell
Get early imaging - CT/cystoscopy to find complications or underlying casue
What are the complications of pyelonephritis?
Severe sepsis
Renal scarring leading to CKD
Pyonephrosis
Preterm labour in pregnancy
What is chronic pyelonephritis?
Repeated infections leading to fibrosis (scarring)
More common in obstructive systems resulting in urinary reflux such as strictures caused by UTIS, VUR
Diagnosis is made radiologically - small scarred shrunken kidney
More common in children - often asymptomatic and presents first as CKD
What is emphysematous pyelonephritis?
Rare and severe form of acute pyelonephritis caused by gas-forming bacteria, assoicated with high mortality rates.
Fails to respond to empirical antibiotics and CT will show gas around kidney. Most common in diabetics.
