Chlamydia Flashcards
Chlamydia trachomatis - trachoma biovar
Most common bacterial disease sexually transmitted
Endometriosis
Salphingitis inflamm of fallipian tubes
Non-gonococcal urethritis
Can spread to prostate
Serovars D-K (ocular type can cause blindness)
C psittaci
Transmitted from birds
Causes pneumonia
Prevalence in females
Young women - 7X national rate
5X overall female rate
C pneumonia
Causes pneumonia and asthma
Increase risk of atherosclerosis
Usually the TWAR STRAIN
Transmission normally in schools
Treatment is azithromycin
Chlamydia characteristics
Gram negative
Obligate intracellular parasite
Can’t make own atp
Have ATP/ADP translocase transport proteins (switch bacterial adp for human atp)
Outer membrane
OmpA used for serovar classification and highly immunogenic
OmcA cysteine rich
OmcB mediates bacterial adhesion
Don’t have detectable peptidoglycase so lysozyme has no effect
TARP Translocated Actin Recruiting Phosphoprotein
Mechanism of host cell entry
Delivered thru TTSS type 3 secretion system
Causes local actin nucleation
Rearrangement of filaments facilitates elementary body internalization via endocytosis
C trachomatis infx method
Uses FGF2 pathway
Binds to elementary bodies (found in infective form)
Facilitates attachment and internalization via surface HSPG (heparan sulfate proteoglycan) n fgfr (fibroblast growth factor receptor)
Entry into host cell
Done via TARP, FGF2 pathway, PDGFR-beta (platelet derived growth factor), Abl kinase system (activated actin cytoskeleton)
Life cycle of trachomatis
Extracellular Elementary body eb
= infective form that is transmitted
= adapted to extracellular life
-taken up by mucosal epithelial cells
Intracellular reticulate body rb
= inside cell has endowment body around it
Rb--> binary fission Transloxated to peri Golgi region Rapidly multiples Rbs convert to eb Eb are released
Later:
Lysozyme mediated repair of plasma membrane (allows for host survival -need calcium actin depolymerization)
Allows for retention of some bacteria
Lymphogranuloma venerum
In trachomatis
Causes host cell lysis
Clinical manifestations for trachomatis
A-C keratoconjunctivitis - trachoma n blindness
D-K (e most common) inclusion conjunctivitis / urethritis cervicitis proctitis - epidymitis endometriosis salphinitis
L1-L3 lymphogranuloma venereum - fibrosis n rectal strictures
Lgv strain
More invasive produce disease in lymph tissue
Non lgv
Infects squamo columnar epithelium
Causes EYE INFX genital tract n respiratory tract
Immune inductive sites
Happens when elementary bodies of trachomatis ascend to infect endometrium of fallipian tubes
Causes inflammatory reaction w influx of macrophages n neutrophils into submucosa
Inductive sites contain B T dendritic cells n macrophages
They coordinate imitation of acquired immune response
Trachomatis pathogenesis
Infects squamocolumnar epithelial cells of the eye, respiratory tract and genital tract
Repeated infx induces inflammatory changes leading to tissue scarring and damage = loss of fx
W/o treatment infx will persist for years
What is trachoma
Chronic conjunctivitis associated w infection by serotypes a b ba and c
Preventable blindness
Inclusion conjunctivitis
Acute ocular infx similar to trachoma
Caused my serovar d-k
Trachoma clinical manifestations
Conjunctivitis w small lymphoid follicles in conjunctiva (indicates that it is active)
Reinfx
PCR indicates presence or absence
Grade 1 trachoma
Mostly In kids
Red sticky eyes
Inflammation follicular stage
Grade 2 trachoma
Intense inflammation
Can’t see blood vessels in inner surface of eyelids
Grade 3 trachoma
Inner lining becomes scared
Seen after repeated infx
Looks like white streaks
Grade 4 trachoma
Due to trichiasis
Blinding corneal opacity w entropion and trichiasis
Scarring causes inner lining to thicken and change shape of eyelid
Pulls eyelashes towards eyeball
Grade 5 trachoma
Corneal opacity
Smoky white
Eyelashes rub in cornea
Trachomatis diagnosis is made of 2 of the following are present
Lymphoid follicles in upper tarsal conjunctiva
Conjunctival scarring
Vascular Pannus
Limbal follicles or their sequel as the Herbert’s pits
Serotypes d-k responsible for
Adult inclusion conjunctivitis aic
And
Urogenital disease
Inclusion bodies
Intracytoplasmic basophilic seen in conjunctival scrapings
Fill up most of the cytoplasm and push nucleus to periphery
Usually one inclusion per cell
Smaller in psittaci n pneumoniae
Treatment for trachomatis
Tetracycline
Erythromycin
Azithromycin 1x only
Treat for 3 weeks
Reiters syndrome
Sex associated reactive arthritis Sara
Conjunctivitis
Urethritis
Arthritis
Pelvic inflammatory disease
Trachomatis impt cause of salphingitis
Linked to infertility bc of tubal scarring
40-50% asymtpomatic ppl have chlamydial endometritis associated w mononuclear infiltrates
Lymphogranuloma venerum lgv
Caused by L strain of trachomatis
Symptom inguinal lymphadenopathy
Transient genital lesion followed by multiocular suppurative lymphadenopathy
Becomes a mass of nodes
