Urinary tract infections (R1) Flashcards
Clinical physiology
- Is the urine generally sterile?
- What are the 3 categories of normal defences against UTI’s?
Yes
Mechanical, chemical, commensals
Clinica physiology
- 2 examples of mechanical defences against UTIs
Flow of urine –> flushes out bacteria and prevents adherence
Vesicoureteral junction –> one way valve
Clinical physiology
- 3 examples of chemical defences?
- 2 types of commensal bacteria?
Chemical: low pH, high urea, low osmolarity (few nutrients for growth)
Commensals: streptococci, lactobacilli
Aetiology
- Acronym for bacteria causing UTI’s?
SEEEK PP
Aetiology
- SEEEK PP bacteria?
- Which ones are gram positive/negative?
Staphylococcus saphrophyticus +
E coli -
Enterococcus +
Enterobacter -
Klebsiella -
Proteus -
Pseudomonas -
Aetiology
- Which bacteria is most common; second most common?
- Which bacteria affects young, sexually active women?
- Which bacteria can cause stones?
- Are all of these bacteria normal residents of the bowel?
- E coli > staphylococcus saphrophyticus
- S. saphrophyticus
- Proteus
- Yes: can make it into urinary tract by forwards wiping
Aetiology
- Examples of viral UTIs?
- Risk factors?
Adenovirus, CMV, BK polyomavirus
More common in children and immunocompromised individuals
Aetiology
- Examples of fungal UTI’s
- Risk factors?
Candida > cryptococcus
Hospitalisation + cathethers
Prolonged antibiotics
Diabetics
Applied biomedical sciences
- Upper versus lower UTI’s?
Upper UTI’s affect the kidneys
- Pyelonephritis
Lower UTI’s affect below the kidneys
- Ureter: ureteritis
- Prostate: prostatitis
- Bladder: cystitis
- Urethra: urethritis
Applied biomedical sciences
- Do UTI’s tend to be caused by ascending or descending infections?
Much more common ascending
Complications
- Of lower UTI?
- Of upper UTI?
- Of proteus infections?
- Of antibiotic use?
- Of infection in pregnancy?
Lower UTI: may ascend to become upper UTI
Upper UTI: sepsis, abscess, scarring of kidney –> CKD
Proteus: stones
Antibiotics: resistance
Pregnancy: prematurity, low birth weight
Prevention
- Behavioural?
Prevent stasis: drink fluids often, empty bladder often
Wipe from front to back
Pee after sex
Risk factors?
History?
- Pain (suprapubic, flank; itis positive)
- Haematuria
- Irritative symptoms: dysuria, FUN (frequency, urgency, nocturia)
- Pyelonephritis: N&V, fevers/chills/rigors
- Prostatitis: obstructive symptoms
- Urethritis: smelly urine
Exam
- Vital signs
- Abdomen
- Pyelonephritis: fever, possibly sepsis
- Urinary retention: distended abdomen
- Cystitis: suprapubic tenderness
- Renal tenderness: pyelonephritis
Investigation
- What test confirms the diagnosis
Urine: FWT and MCS
Investigation: FWT results
- SG
- pH
- Leukocytes
- Blood
- Nitrites
- Proteins
- Glucose
SG: may be increased, due to high levels of bacterial proteins
pH: may be increased
Leukocytes: present
Blood: present
Nitrites: present if gram negative bacteria
Proteins: may be present
Glucose: may be present (risk factor)
Investigation: MCS
- Is it the gold standard?
- What indicates UTI?
- Additional findings?
> =10^5 CFU/mL indicates UTI
Bacteria, RBC, WBC may be present
Investigations
- Additional investigations for those who are sick?
Labs
- FBC: leukocytosis
- CRP: elevated
- Blood cultures: if fever
Imaging
- Ultrasound, CT abdo/pelvis or KUB
Principles of management?
- Fluids: IV if septic, drink plenty (flush out bacteria)
- Symptom management: pain (NSAID or phenazopyridine), vomiting
- Antibiotics (empirical –> specific)
- Additional considerations
Management: antibiotics
- Considerations before using gentamycin?
- Are antibiotics needed in non pregnant females with asymptomatic bacteriuria?
- Gentamycin is nephrotoxic: check renal function first
- No
Acute cystitis: antibiotics
- Oral trimethoprim or nitrofurantoin
- If contraindicated, oral cefalexin
Non severe pyelonephritis (none of >=38 degrees, N&V, sepsis): antibiotics
- Oral Augmentin (amoxicillin + clavulanic acid)
- If allergic: oral ciprofloxacin
Severe pyelonephritis (atelast one of >=38 degrees, N&V, sepsis): antibiotics
- IV gentamycin + amoxicllin/ampicillin
- If contraindicated: IV cefrtiaxone/cefotaxime
Acute prostatitis: antibiotics
- Non severe?
- Severe?
Non severe: oral trimethoprim or cefalexin
Severe: as per severe pyelo (- IV gentamycin + amoxicllin/ampicillin, or IV cefrtiaxone/cefotaxime if contraindicated)
Pregnancy: antibiotics
- Acute cystitis
- Pyelonephritis
Cystitis: oral nitrofurantoin or cefalexin
Pyelo: as per severe pyelo (- IV gentamycin + amoxicllin/ampicillin, or IV cefrtiaxone/cefotaxime if contraindicated)
Candida infection: antifungal?
Oral fluconazole
Additional step for any men with a UTI?
Refer to urology
Treating recurrent infections in non pregnant women?
- Treat acute infections with antibiotics
- Educate on prevention strategies
- If post menopausal: offer topical estrogen
- As a last resort: antibiotic prophylaxis - trimethoprim, nitrofurantoin, cefalexin.
How would you explain a UTI to a patient?
How would you explain the symptoms?
Draw out urinary tract.
UTI: when bugs grow in your kidneys.
The bacteria irritate the lining of your urinary tract, causing
- Pain at the site (cystitis, pyelonephritis)
- Dysuria, frequency/nocturia and urgency.
- Haematuria: blood to be passed in urine.
Kidney infections can make you generally unwell
- Nausea and vomiting
- Fever + sepsis
