Urinary Tract Infections

Question 1

What are lower UTIs

Answer 1

Cystitis, urethritis and prostatitis.

Question 2

What are upper UTIs

Answer 2

Pyelonephritis, intra-renal abscess and perinephric abscess

Question 3

What are uncomplicated UTIs

Answer 3

Infection in a structurally and neurologically normal urinary tract. Shorter duration

Question 4

Whar are complicated UTIs

Answer 4

Infection in a urinary tract with functional or structural abnormalities (cystitis of long duration or haemorrhagic cystitis

Question 5

What are some signs and symptoms of lower UTIs

Answer 5

Frequency, urgency, dysuria, suprapubic pain, haematuria, smelly or cloudy urine

Question 6

What are signs are symptoms of infection of pelvic/kidneys

Answer 6

Loin pain and tenderness, high fever and systemically unwell

Question 7

What are some of the predisposing factors for UTIs

Answer 7

• Obstruction eg, calculi, tumours, benign prostate hyperplasia.
• Viscoureteral reflux,
  Incomplete bladder emptying,
• Diabetes, sickle cell or immunosuppression,
• Bladder instrumentation/ foreign bodies,
• Congenital structural abnormalities,
• Sexual activity/pregnancy

Question 8

What is significant about catheterisation?

Answer 8

Incremental risk of CAUTI associated with each additional day of catheterisation

Question 9

What are some of the host defences for urinary tract infections

Answer 9

• Urine (osmolality and pH),
• Sloughing of epithelial cells,
• Urine flow and micturition,
• Mucosal inhibitors of bacterial adherence,
• Complement activation,
• Inflammatory response,
• Commensals

Question 10

What are the most common causes of UTIs?

Answer 10

1) E.coli,
- Klebsiella
- Staphylococcus saprophyticus
- Candidia albicans,
- Trichomonas vaginalis,
- shistosoma haematobium

Question 11

Describe how e.coli adheres to cells

Answer 11

Specific adhesion to uroepithelial cells via fimbirae

Question 12

Describe the bacterial response to adhesion

Answer 12

Stimulates growth and reproduction and a biofilm may develop. Bacteria with type 1 fimbriae may become internalised by phagocytes.

Question 13

Describe pathogenic factos of E.coli

Answer 13

K antigen - Forms a micro-capsule and confers resistance to phagocytosis.
Haemolysin - Damages tissue membranes in vivo causing kidney damage

Question 14

Describe features of preoteus mirabilis

Answer 14

Gram neg bacillus with pertrichous flagellae. It produces urease which makes urine less acidic. Favouring colinisation of bacteria

Question 15

Describe features of staphylococcus saprophyticus

Answer 15

Gram positive bacterial which is part of the normal microbiota of female perineum and vagina. Commonly causes community acquired UTIs and symptomatic cystitis

Question 16

Describe some features of candida albicans

Answer 16

It is a fungus which is an opportunistic pathogen in immunocompromised individuals and is often associated with antibiotic use

Question 17

Describe features of trichomonas vaginalis

Answer 17

Protozoan which prefers pH of 6. Less common in males

Question 18

How can you diagnose UTIs?

Answer 18

• History taking (clinical signs and symptoms),
• Urine dipstick,
• Laboratory diagnosis

Question 19

What two symptoms increase the probability by over 90% that the diagnosis is UTIs?

Answer 19

Frequency and dysuria

Question 20

What are the main indications for urine culture?

Answer 20

• Children,
• Male UTI,
• Immunocompromised,
• Pregnancy,
• Toxic appearance,
• Underlying medical/urological disorder,
• Recently hospitalized,
• Recently hospitalized,
• recently instrumented,
• Recently on antibiotics,
• Recent treatment failure

Question 21

What are some of the common oral antibiotics used for lower UTIs

Answer 21

Nitrofurantoin and trimethoprim (these 2 are most common) Ciprofloxacin, pivmecillinam and amoxicillin

Question 22

What are some of the common oral antibiotics used for upper UTIs (pyelonephritis)

Answer 22

Co-trimoxazole, co-amoxiclav or ciprofloxacin

Question 23

What are some of the possible complications of UTIs?

Answer 23

• Recurrent infections,
• Permanent kidney damage,
• Pyelonephritis,
• Low birth weight/premature infants,
• Urethral narrowing in men,
• Sepsis