Infection & Inflammation Flashcards
How is a UTI defined in terms of organisms?
> 10^5 organisms/ml of fresh MSU
What are the RFs for a UTI?
Sexual intercourse Spermicidal lube Pregnancy Menopause ImmunoS DM Catheter/instrumentation Stones Elderly Incomplete bladder emptying (BPH)
What are the bacterial causes of UTI?
E.Coli
Proteus
Staph Saprophiticus
How can UTI’s be subdivided?
Complicated: Abnormal renal/GU tract, voiding difficulty, impaired host defence
Uncomplicated: Normal renal tract + function
What are the Sx of cystitis?
↑Frequency (polyuria) + ↑Urgency Dysuria \+/- Haematuria Foul smelling +/- cloudy Systemic: Fever, rigors, N&V ELDERLY: Confusion
How is UTI investigated?
Urine Dipstick: Nitrates + Leucocytes MSU: >10^5 = DIAGNOSTIC MC&S of MSU Sexual health Hx + Swabs: VVS, NAATs, Urethral swab USS + referral for CTKUB
What are the indications for referral for CTKUB in a UTI?
Pyelonephritis Abnormal organism Persistent haematuria Male Pregnant Child ImmunoS Ongoing Sx despite Abx Underlying RFs Recurrent episode: >2/3mo <50yo w/microscopic haematuria!!
On a dipstick do leukocytes AND nitrates both have to be +ve for UTI treatment?
No \+ve leukocytes OR \+nitrates AND Symptomatic = Tx empirically while waiting for MC&S confirmation
How is a UTI treated in a male?
1) Trimethoprim 200mg BD for 7DAYS- Avoid if poor renal function OR 1) Nitrofurantoin 50mg QDS for 7DAYS -Analgesia: Paracetamol/Ibuprofen 2) Urology referral if meet criteria
When should men with a UTI be followed up?
After 48hours to check urine culture results and if appropriate Abx
How are women treated for a UTI?
1) Trimethoprim 200mg BD for 3DAYS
OR
1) Nitrofurantoin 50mgQDS for 3DAYS
-Analgesia: Paracetamol/Ibuprofen
In pregnancy when should Trimethoprim & Nitrofurantoin be avoided?
Trimethoprim = 1st Trimester Nitrofurantoin = 3rd Trimester
Who should be considered for prophylactic Tx of UTI?
> 3 infections per year in women
Child at high risk of scarring
Trimethoprim
How long does it usually take for Sx of a UTI to resolve?
Usually 48hours
What is pyelonephritis?
Upper UTI of renal pelvis & often parenchyma
What is the pathogenesis of pyelonephritis?
1) Pathogen colonises periurethral area & ascends through urethra towards bladder
2) Fimbria allows bladder epithelial cell attachment & penetration
3) Bacteria continue to replicate & can form biofilms
4) Sufficient colonisation- bacteria ascend via ureter to kidney
5) Infection of renal parenchyma causes inflammatory response
6) Continued inflammatory cascade = tubular obstruction & damage lead to interstitial oedema = interstitial nephritis = AKI
What are the bacterial causes of pyelonephritis?
E.Coli- 95%
Proteus
Staph Saprophyticus
Klebsiella
What are the RFs for pyelonephritis?
Vesicouteric reflux Calculi Stents Pregnancy DM Biliary cirrhosis Outflow obstruction
How does pyelonephritis present?
Rapid onset- 2d 1) Flank pain: Intense & severe, radiates to groin 2) Haematuria Tenderness Worse on urination Foul smelling urine Systemic: Fever, rigors, N&V Oliguria = AKI
How is pyelonephritis investigated?
Urine dipstick: Nitrates, blood, leukocytes
MSU: MC&S
Sexual health: VVS, NAATs, Urethral swab
USS + CTKUB: RULE OUT Hydronephrosis
Bloods: FBC (↑neut), ↑CRP/ESR, U&E, Cultures
When should someone be admitted to hospital w/pyelonephritis?
Signif dehydration Septic Pregnant & pyrexial Elderly Fail to improve significantly after 24hrs of Abx
How is pyelonephritis treated?
1) Abx: Ciprofloxacin 500mg 7days OR Co-Amoxiclav 500/125mg TDS 14days -Pregnant: Cefalexin 500mg BD 1-14days 2) Paracetamol for fever
When should someone w/pyelonephritis be reviewed?
24hours post-Abx
See effect & MCS results
What are the complications of pyelonephritis?
AKI
Renal abscess
Acute papillary necrosis- elderly
Premature labour
