Lecture 12: STI's and PID

Question 1

What are the risk factors for STI’s?

Answer 1

• multiple sexual partners
• no barrier contraception
• early age of first intercourse
• certain sexual practices

Question 2

Why do men get urethral discharge?

Answer 2

• chlamydia trachomatis (obligate intracellular bacterium- gets taken up by macrophages and prevents the phagosome and lysosome from joining). Can be asymptomatic in men, but can cause testicular pain, dysuria, discharge
• neisseria gonorrhoeae (Gram negative diplococci with pili, adheres to epithelial cells. Can cause reactive arthritis: disseminated infection. 90% are symptomatic: thick yellow discharge, +/- dysuria)
• NGU (non-gonococcal urethritis): inflammation of urethra with associated discharge, some STI’s cause this, but can also be pathogen negative

Question 3

How do we investigate for STI?

Answer 3

• white cell count via FBC
• CRP (increased)
• urine sample (microscopy and culture: looks for gonorrhoeae, excludes UTI, NAAT (nucleic amplification tests)-to detect chlamydia seeing as it isnt gram positive or negative)
• urethral swab (look for gonorrhoea)

Question 4

Is discharge in woman always pathological?

Answer 4

No, can be physiological

-secretory phase (cervical mucus is thicker): ask if it is cyclical, any other symptoms, colour etc

Question 5

What STI’s can cause vaginal discharge?

Answer 5

-N.gonorrhoeae
-C.trachomatis (can also present with post coital or intermestrual bleeding, dyspareunia)
Women are generally asymptomatic, so regular screening is required
-Trichomonas vaginalis (trichomoniasis): protozoa flagellate, optimal growth at pH6, causes yellow, foul smelling discharge

Question 6

How do you treat trichomoniasis?

Answer 6

Metronidazole

Question 7

What N-STI’s can cause vaginal discharge?

Answer 7

-Candida albicans> candidiasis: yeast infection, normal flora, activated in immunocompromised states and diabetics and high oestrogen (COCP) and antibiotics. Very itchy, with thick white discharge

-Bacterial vaginosis (BV): Gardnerella vaginalis: in normal vaginal mucosa there is lactobacillus which produces lactic acid and hydrogen peroxide which is protective, so if we have a reduced amount of lactobacillus due to excessive cleaning, it allows gardenerella vaginalis to proliferate and cause infection
=causes offensive smelling, white discharge

Question 8

How do you investigate vaginal discharge?

Answer 8

For chlamydia/gonorrhoea
-vulvovaginal swab
-endocervical swab
For trichomoniasis/BV/candida
-high vaginal swab

URINE DIP IS NOT EFFECTIVE AT DETECTING STI IN WOMEN-urinary system isn’t as connected to reproductive system in women as it is in men

Question 9

What does HPV cause?

Answer 9

Human papillomavirus

• DNA virus, non-enveloped
• causes genital/cutaneous warts
• Virus type 6 & 11 cause 90% of genital infections
• Virus type 16 & 18 have the highest risk of cervical cancer
• vaccination
• PCR (via biopsy/swab)

Question 10

What does HSV cause?

Answer 10

Herpes simplex virus 1 or 2

• both types multiply in epithelial cells of mucosal surfaces
• affects mucosal surfaces so can be genital or oral (cold sores)
• HSV2 is more likely to be associated with HIV
• lifelong disease: initially asymptomatic, but presents with painful ulcers, +/- systemic symptoms
• can be transmitted to baby during birth

Question 11

How do you test and manage HSV?

Answer 11

• swab for PCR/NAAT

- manage with anti-virals e.g. aciclovir: reduces severity but can’t cure

Question 12

What does treponema pallidum cause?

Answer 12

Syphilis

• spiral shaped bacterium
• direct transmission of vertically (across placenta)
• 40% who have syphilis present with HIV
• common in white men, men who have sex with men, age 25-34

Question 13

What are the different types of syphilis?

Answer 13

Primary
-painless ulcer
Secondary
-multisystemic: glomerulo-nephritis, hepatitis, neuro, rash

Question 14

How do you detect and treat syphilis?

Answer 14

Detect via: microscopy/PCR

Treated: penicillin based antibiotics

Question 15

What is common with STI’s?

Answer 15

Co-infections are very common due to similar route of transmission

Question 16

How do you treat bacterial STI’s pharmacologically?

Answer 16

Bacterial: Azithromycin and ceftriaxone (target gonorrhoea and chlamydia, one abx can augment the effect of the other)

Question 17

How do you treat specific N-STI’s pharmacologically?

Answer 17

Candida: anti-fungals
BV: antibiotics (Metronidazole)

Question 18

What is PID?

Answer 18

Pelvic inflammatory disease
-inflammation of the uterus, fallopian tubes and ovaries
-caused by ascending infection (chlamydia trachomatis, neisseria gonorrhoea, gardnerella vaginalis)
(IUD’s can become infected, uterine interventions)

Question 19

How does PID present clincally?

Answer 19

-lower abdominal pain
-dyparenuria
-discharge
-abnormal uterine bleeding
+/- fever
Do a bimanual vaginal investigation to assess cervix and fundus of the uterus

Question 20

What are the differentials for PID?

Answer 20

• appendicitis
• UTI
• ectopic pregnancy
• endometriosis
• ovarian cysts

Question 21

What complications can arise from PID?

Answer 21

• chronic pelvic pain
• pelvic abcesses (tubo-ovarian)
• subfertility: adhesions and fibrosis due to chronic inflammation (also increases risk of ectopic pregnancy)
• peritonitis (as it is open to the peritoneum)
• Fitz-Hugh Curtis syndrome (peri-hepatitis)

Question 22

How do you manage PID?

Answer 22

Prevention is better than cure

• give antibiotics (don’t wait for swabs to come back), firstly broad spectrum, +/- IV antibiotics is very unwell
• analgesia
• contact screening
• LAPAROSCOPY: if patients fail to respond to treatment