Infections of the Genito-Urinary Tract

Question 1

Why are females more vulnerable to infection with fecal bacteria?

Answer 1

• The urethra is shorter and nearer to the anus

- Due to the nature of intercourse

Question 2

What is urethritis?
What is cystitis?
What is dysuria?
What is pyuria?
What is Pyelonephritis?

Answer 2

• Urethritis is inflammation of the urethra
• Cystitis in inflammation of the bladder
• Dysuria is painful urination
• Pyuria is urine that contained pus
• Pyelonephritis is kidney infection, characterised by fever and back pain

Question 3

Most common UTI bacterias (three)

Answer 3

E.coli - gram negative rod

Proteus mirabilis - Gram negative pleomorphic rod - swarming motility

Staphylococcus saprophyticus - gram positive coccus

Question 4

What is E.coli?

Answer 4

• E.coli is a gram-negative motile bacillus.
• Also causes GI-infections, but UTIs commonly caused by specific strains of E.coli known as UPEC.
• UPEC possesses potent adhesins for attachment to epithelium

Question 5

In terms of UPEC Pilus adhesins, what is a type I pili and P-fimbriae?

Answer 5

Type I pili: Binds mannose receptors, common on glycoproteins in uroeputhelium

P-fimbriae: Binds to globobiose

Question 6

What is Staphylococcus Saptophyticus?

Answer 6

• Gram positive - cocci
• Haemagglutinin key to attachment to cells
• Common cause of UTIs in young women
• Coagulase negative
• Nobobiocin resistant
• Most common in young women

Question 7

How do we treat symptoms of UTI in the community? (dysuria etc…)

Answer 7

• Swift antibiotic treatment to prevent complications of kidney infection
• 3-day course in women, 7 day in men
• Common antibiotics include Nitrofurantoin, Ciprofloxacin, Penicillins and trimethoprim

Question 8

How do we treat symptoms of UTI in the hospital?

Answer 8

• Similar to community but may require IV antibiotics
• Removal and changing of catheter and bag
• Resistant E.coli infections now treated with Plazomicin in USA - expected to come to UK soon.

Question 9

How are UTIs transmitted?

Answer 9

Any form of sexual activity in which no barrier is used and exchange of fluid or contact with mucosal epithelium

Question 10

Main organisms for:

1. ) Gonorrhoea
2. ) Chlamydia
3. ) Syphilis

Answer 10

1. ) Neisseria Gonnorhoea
2. ) Chlamydia trachomatis
3. ) Treponema Pallidum

Question 11

N. gonorrhoeae pathogenesis (factors and components)

Answer 11

• Surface pili for attachment
• Opa proteins aid attachment
• Por proteins - nucleate actin aiding cell invasion
• Possesses IgA protease - aids survival inside host cells.
• If released into bloodstream - can disseminate infection to other sites fever, arthritis
• Co infection of HIV and N. gonorrhoea increases transmission of HIV by 500%

Question 12

How is syphilis transmitted?

Answer 12

Syphilis is transmitted by sexual contact via minute skin abrasions

• Vertical transmission - cross placental: Congenital syphilis

Question 13

Why is congenital syphilis significant?

Answer 13

Congenital syphilis can lead to still birth, birth deformities, silent infection (presents as facial and tooth deformities at 2 years)

Question 14

Complications of chlamydia infection in Women

Answer 14

Asymptomatic infection in 70% of women.
Urethral infection

• Pelvic inflammatory disease 40% - ascending infection involving uterus, fallopian tubes, and other pelvic structures.