UTI

Question 1

Symptoms of UTI

Answer 1

Dysuria ( difficulty , pain or discomfort when passing urine. Sometimes described as burning.

2) frequency = a frequent urge to urinate - even though little comes out when the patient goes to the toilet.

Question 2

When a GP takes a dipstick test on urine sample , what is it likely to show if the patient has a UTI ?

Answer 2

1) nitrites would be positive

2) leukocyte esterase would be positive

Question 3

Why are nitrites generally found in urine in a UTI .

?

Answer 3

Due to the reduction of nitrates to nitrite by some gram negative bacteria such as E.Coli.

Question 4

Which bacteria would tend to be present if there is no positive nitrites test in urine?

Answer 4

Staph saprophyticus and enterococcus ( gram positive) because they do not produce nitrate reductase therefore the dipstick would be negative for nitrite as nitrate would not be a reduced to nitrites.

Question 5

Why would leukocyte esterase positive test be a good indication of UTI ?

Answer 5

• leukocyte esterase is an enzyme released by neutrophils and macrophages. A urine dipstick positive for this enzyme indicates pyuria ( an increased number of leukocytes and white blood cells in urine).

Cystitis and urethritis are common causes of pyuria.

Question 6

What is the likely mechanism of infection for UTI ?

Answer 6

Contiguous ( direct spread eg through sexual intercouse)

Question 7

What antibiotic would you tend to use for UTI?

Answer 7

First antibiotic used - nitrofurantoin.

2) trimethoprim

Trimethoprim is less commonly used now because a lot of people are resistant now.

Question 8

What is the mechanism of. Action of nitrofurantoin?

Answer 8

Damages bacterial DNA

Question 9

Gram stain appearance of Ecoli

Answer 9

Bacilli/rod shaped

Stained pink