NGU

Question 1

Which STI has been associated with balano-posthitis?

Answer 1

Mycoplasma genitalium (in a single study)

Question 2

What %age of men have dual infection with chlamydia and m gen?

Answer 2

10% (up to)

Question 3

List the most common pathogens of non-gonococcal urethritis (NGU)? (6)

Answer 3

C. trachomatis
M. genitalium 
Ureaplasmas
T. vaginalis 
Adenoviruses
Herpes simplex virus

Question 4

What is the prevalence of C. trachomatis in NGU?

Answer 4

50% (up to)

Question 5

What is the prevalence of M. genitalium in NGU?

Answer 5

50% (up to)

Question 6

What factors make pathogen-negative NGU more likely?

Answer 6

Increasing age
Absence of discharge
No clinical symptoms

Question 7

What factors affect the risk of Trichomonas vaginalis causing NGU?

Answer 7

Background prevalence in the local community (low in UK)
More common in non-white ethnic groups
Isolation more likely in men >30 years old

Question 8

Which ureaplasma is most likely pathogenic and a cause of NGU - urealyticum or parvum?

Answer 8

Ureaplasma urealyticum

Question 9

What other symptom/sign might be present if NGU is due to an adenovirus?

Answer 9

Conjunctivitis

Question 10

What other possible causes of NGU have occasionally been identified? Consider infective and non-infective

Answer 10

EBV
Neisseria meningitidis
Haemophilus
Urethral stricture
Foreign bodies

Question 11

What clinical signs may prompt you to assess for NGU?

Answer 11

Urethral discharge

Balano-posthitis

Question 12

What criteria by microscopy must be met for a diagnosis of NGU?

Answer 12

five or more PMNLs per high power (􏰁1000) microscopic field (averaged over five fields with the greatest concentration of PMNLs) on a smear from anterior urethra

Question 13

Which part of the urethra should a sample be taken from for assessment of NGU?

Answer 13

Anterior urethra approximately 1 cm from urethral meatus

Question 14

What microscopic field is classed as high power?

Answer 14

x1000

Question 15

If urethral discharge is present how should this be sampled?

Answer 15

Sample without placing loop or swab inside meatus, if it can be adequately sampled then this is the recommended method for obtaining a smear

Question 16

What device sis preferred for sampling the urethral meatus in men?

Answer 16

5-mm PLASTIC LOOP

It is less painful than a Dacron swab which is less painful than a Rayon swab

Question 17

If urethral smear is negative for NGU or microscopy is not available, what other assessment may be made to further consider NGU?

Answer 17

Performing a LEUCOCYTE ESTERASE DIPSTICK on the remains of the FVU specimen could be considered and if 􏰂1+ OR MORE, a diagnosis of NGU could be made.
However it t does not have adequate sensitivity to be considered a reliable rapid diagnostic test for acute NGU instead of microscopy

Question 18

If microscopy and a dipstick analysis are negative for NGU but the patient still has symptoms, what should the next approach of investigation be?

Answer 18

Attend for early morning smear and hold urine overnight.

Question 19

When performing a urethral smear what is the optimum time to ensure a definite diagnosis in a symptomatic man?

Answer 19

2-4 hours (conventional approach). However no definitive evidence

Question 20

What are the benefits of treating NGU with doxycycline 100mg BD for 7 days?

Answer 20

> 95% effective in men who are chlamydia positive

M. genitalium-positive there is no evidence that it induces antimicrobial resistance

It is as effective as azithromycin 1 g in men who are U. urealyticum-positive.

Question 21

Whys is azithromycin not used as first line treatment for NGU?

Answer 21

<90% effective in men who are M. gen positive

If M. gen positive - risk of developing 23sRNA gene mutation and therefore antimicrobial resistance

Question 22

What is the duration of the ‘look back’ period for partner notification for NGU?

Answer 22

4 weeks

Question 23

What is the definition of persistent NGU?

Answer 23

symptoms do not resolve following treatment

Question 24

What is the definition of recurrent NGU?

Answer 24

recurrence of symptoms within 30-90 days following treatment of acute NGU?

Question 25

How common is persistent NGU?

Answer 25

15-25%

Question 26

How common is recurrent NGU?

Answer 26

10-20%

Question 27

What percentage of persistent NGU is an infectious cause identified?

Answer 27

<50%

Question 28

In addition to re-examination and assessment and testing for mycoplasma genitalium, what else should be considered testing for in persistent/recurrent NGU?

Answer 28

Trichomonis vaginalis NAAT (if available)