Lecture 18: Microbial diseases of the urinary and reproductive system
Edith Porter, M.D.
1
Structure & function and normal microbiota of the
urinary and reproductive system
 Ports of entry
 Diseases of the urinary system

 Bacterial

Diseases of the reproductive system
 Bacterial
 Viral
 Fungal
 Protozoan

TORCH
2
3
Note the short urethra and
proximity to anus
4
5




Urinary bladder and upper urinary and
reproductive tract sterile
Urethral opening colonized with skin flora
(mainly gram+ bacteria) and in men,
Mycobacterium smegmatis
Lactobacilli predominant in the vagina
Urine is normally sterile but can be
contaminated by the microbiota of the
urethral opening
6


Microbes usually enter the urinary
system through the urethra
Microbes usually enter the reproductive
system through the vagina (females) or
urethra (males)
7



Urinary bladder infection
Dysuria: difficult, painful and imperative urination
Usually caused by
 E. coli
 S. saprophyticus (in female)

May also be caused by
 Associated with kidney stones: Proteus
 Nosocomial: Klebsiella, Pseudomonas, Enterococcus
faecalis

Antibiotic-sensitivity tests should guide treatment
8



Clean catch urine (midstream urine after
urethral opening had been cleansed)
Refrigerate until urine is processed, because
there is typically some contaminating normal
flora present (< 10,000/ml)
In general > 100,000 bacteria/ml = infection
 Single organism
9





If cystitis left untreated pyelonephritis may follow
Fever, flank or back pain
75% caused by E. coli
In the elderly danger of sepsis
i.v. antibiotics
Diseased kidney
Normal kidney
10
Major public health impact
In the US ~15 Mio new cases/year (or ~30
new infections /min)
 Female often without major symptoms
 Major cause of infertility
 Prevented by (properly used) condoms
and vaccination (genital warts)


11

Most common bacterial STIs
 Neisseria gonorrhoeae (gonorrhoea)
 Chlamydia trachomatis (non-gonococcocal urethritis, NGU)
 Treponema pallidum (Syphilis)
 Treated with antibiotics

Most common viral STIs
 Herpes simplex 2 (genital herpes)
 Papilloma virus (genital warts, cervical cancer)

Other STIs
 Fungal: candidiasis
 Protozoan: trichomonas
12


Gram negative diplococci
Attaches to columnar epithelial cells via pili
 Oropharyngeal, eyes, rectum, urethra, opening of cervix, external
genitals of pre-pubertal females
 Antigenic variation of pilin and expression of opa which blocks T cells
and immunological memory

Typically urethritis, cervicitis
 Females may be asymptomatic; males have painful urination and pus
discharge


Old disease (name coined in A.D. 150 “flow of semen”)
In rare untreated cases systemic spread and joint infection
 Arthritis (one knee joint only)

Upon birth
 Ophthalmia neonatorum
13
Neutrophil
14
15
16

Chlamydia trachomatis
 May be transmitted to
newborn's eyes
 Painful urination and watery
discharge


Mycoplasma hominis
Ureaplasma urealyticum
Watery discharge in CT
17
Infects epithelial cells
Special life cycle with 2 life
forms
 Elementary body, resistant
and infectious
 Reticulate body, sensitive
and proliferating
 Infection must be treated
through 2 life cycles of CT


18
48 h -72 h
19
Contribute to intracellular survival and proliferation
In part secreted via Type III secretion apparatus
Effect actin rearrangement and endocytic uptake of CT
CT inserts proteins in inclusion (endosome) membrane
that prevent fusion of host lysosomes
 CT releases proteins into the cytoplasma that interfere
with NFkB signal transduction, a key pathway of the
acute inflammatory and innate immune response




20
N. gonorrhoeae
C. trachomatis
Scarring can block
uterine tubes
 Chronic abdominal pain
 Infertility and ectopic
pregnancies



Laparascopic image showing acute inflammation
of right tube, fimbriae and ovaries
21

Nulceic acid amplification tests most
accurate
 PCR based


Antigen detection (ELISA)
Culture (gonorrhoea > NGU)
22


Treponema pallidum, gram negative spirochete
Invades mucosa or enters through skin breaks
23



1. stage: acute ulcer (painless,
hard), highly infectious
2. stage: systemic spread into
skin, highly infectious
3. stage: gumma,
immunological response in
tissue, neurosyphilis,
24

Direct diagnosis:
 Darkfield microscopic identification of bacteria
 Staining with fluorescent-labeled, monoclonal
antibodies

Indirect serological diagnosis
 Reagins: antibodies against conserved structures
on Treponema
 Specific antibodies
25




Herpes simplex virus 2 (Human
herpesvirus 2 or HHV 2)
Burning sensation followed by
development of fluid filled vesicles
Sometimes non-symptomatic
Neonatal herpes transmitted to fetus or
newborn
 Spontaneous abortion of severe fetal damage

Virus enters latency with recurrence
26
“Unlike love herpes is forever”
27




Human papillomaviruses
HPV 16 causes cervical cancer
and cancer of the penis
DNA test to detect cancercausing strains
Vaccination against HPV
strains
28




Candida albicans
Severe itching and thick yellow cheesy
discharge
Result from opportunistic overgrowth
Increased during pregnancy and in diabetic
women
29
Trichomonas vaginalis
Protozoan
Found in semen or urine of male
carriers
 Vaginal infection causes irritation
and profuse discharge (foul
smelling, frothy)
 Diagnosis by microscopic
identification of protozoan



30


Toxoplasma
Other
 Treponema pallidum
 Listeria monocytogenes



Rubella
Cytomegalovirus
Herpes simplex
31







Urethra opening (gram+ bacteria, Mycobacterium smegmatis) and vagina
(Lactobacillus spec.) are populated by normal microbiota.
The female urethra is much shorter than the male. This and close vicinity
to anus makes women more prone for urinary tract infections.
Diseases of the urinary system are mainly of bacterial origin. In out
patients: E. coli, S. saprophyticus; associated with kidney stones: Proteus;
noscomial: Enterococcus faecalis, Klebsiella, Enterobacter, Pseudomonas.
Females often have less symptoms than men during an STI.
Infertility is a frequent complication after STI.
Diseases of the reproductive system of bacterial origin: Neisseria
gonorrhoeae, Chlamydia trachomatis, Treponema pallidum; of viral: Herpes
simplex 2, Papilloma virus; of fungal: Candida albicans; of protozoan:
Trichomonas vaginalis
Birth defects are in particular associated with TORCH (Toxoplasma,
Rubella , Cytomegalovirus, Herpes simplex).
32
1) Cystitis is most often caused by
A) Escherichia coli.
B) Leptospira interrogans.
C) Candida albicans.
D) Neisseria gonorrhoeae.
E) Pseudomonas aeruginosa.
2) Which of the following is often diagnosed by detection of antibodies against the causative agent?
A) Nongonococcal urethritis
B) Gonorrhea
C) Syphilis
D) Cystitis
E) Candidiasis
3) Normal microbiota of the adult vagina consist primarily of
A) Lactobacillus.
B) Streptococcus.
C) Mycobacterium.
D) Neisseria.
E) Candida.
33