Infectious diseases

Question 1

Define:

1. Cystitis
2. Pyelonephritis
3. Asymptomatic bacteriuria

Answer 1

1. Cystitis: infection of the bladder (lower UTI)
2. Pyelonephritis: infection of the parenchyma and collecting system of the kidney (upper UTI)
3. Asymptomatic bacteriuria: significant bacteria present in the urine with no symptoms

Question 2

Pathogenesis of UTIs

Answer 2

• Most UTI’s result from bacteria ascending from the urethra
• Haematogenous seeding of the kidneys may occur when a patient is bacteraemic with organisms such as S.aureus or candida (rare with gram –ve enteric bacteria)
• Most bacteria causing UTI’s originate in the bowel
• Colonise the lower vagina and periurethral mucosa
• Colonise the distal urethra into the bladder
• Up the ureters into the renal parenchyma

Question 3

Predisposing factors for UTI

Answer 3

• Age
• Gender
• Pregnancy
• Sex
• Menopause
• Diabetes

Question 4

Community acquired UTI causative organisms

Answer 4

1. E coli

2. staph saprophyticus

Question 5

Hospital acquired UTI microorganisms

Answer 5

E coli and Enterobacteriaceae

Increased frequency of proteus, enterobacter, serratia, pseudomonas aeruginosa

Question 6

Clinical features of lower UTI

Answer 6

CYSTITIS:
Dysuria
Frequency 
Urgency
Suprapubic heaviness or tenderness
Urine turbid/bloody/smells

Question 7

Upper UTI clinical features

Answer 7

• Flank or back pain – unilateral or bilateral
• Fever, chills
• Rigors suggest bacteraemia
• Headache, nausea, vomiting, prostration
• Often with dysuria, frequency, urgency

Question 8

Investigations that can be used to diagnose UTI

Answer 8

• MSU
• Suprapubic aspirate
• CSU
• Bag of urine

Question 9

Cells assessed in urine microscopy

Answer 9

White cells: elevated WCC = pyuria
Red cells: bleeding, and if they’re dysmorphic it indicates glomerular pathology
Squamous epithelial cells: presence indicates contamination

Question 10

Significant bacteremia in females and males

Answer 10

Females: >10^2/ml
Males: >10^3/ml

Question 11

Typical antibiotic used in UTIs in the general practice setting

Answer 11

• Amoxicillin
• Augmentin
• Cephalexin
• Nitrofurantoin
• Trimethoprim
• Norfloxacin

Question 12

Which urinary tract abnormalities are associated with UTI’s in children?

Answer 12

¥ Vesico-ureteric reflux

¥ Ureteral duplication

¥ Trabeculated bladder

¥ Hydroureter

¥ Ureteropelvic junction obstruction

Question 13

What would indicate a UTI on dipstick?

Answer 13

• Leucocytes

- Nitrites