Chkamydiaeceae Flashcards
They contain both the DNA and RNA, ribosomes and they produce their own proteins, lipids and
nucleic acids
o They were once thought to be large viruses, but they contain both DNA and RNA
CHLAMYDIACEAE
Chlamydiaceae stain poorly with gram stain, but they could be better visualized with the
Gutsein Stain
Non-motile, small (0.2 – 1.5um), resembles gram-negative cell wall, obligate intracellular
bacteria that requires living cells for growth
CHLAMYDIACEAE
Requires the biochemical resources of the eukaryotic host cell‘s environment to fuel their
metabolism for growth and replication – “energy parasite”
CHLAMYDIACEAE
They have tropism for columnar epithelial cells
CHLAMYDIACEAE
Posses a heat stable, family specific antigen that is an essential component of the cell
membrane (LPS
CHLAMYDIACEAE
Morphologic forms of Chlamydiaceae:
Replicative form
Intracellular and metabolically active
Reticulate body
Morphologic forms of chlamydiaceae:
Inefective form
Extracellular and structurally resembles a gram-negatice bacillus
Have a rigid cell wall
Elementary body
2 components of the outer membrane of elementary body
MOMP( major aouter membrane protein and lipopolysaccharide (LPS) antigen
- Major cause of pelvic inflammatory disease(PID) and ocular trachoma
Chlamydia trachomatis
- Major cause of pelvic inflammatory disease(PID) and ocular trachoma
Chlamydia trachomatis
Serotype of endemic trachoma
Serotypes A, B, Ba, C
serotype of lymphogranuloma venereum (LGV)
Serotypes L1, L2, L3
serotype of PID, urethritis, cervicitis, epididymitis, inclusion conjunctivitis
Serotypes D- K
Associated with infertility and ectopic pregnancy
Chlamydia trachomatis
Intraperitoneal spread may cause peritonitis or perihepatitis
(Fitz-Hugh-Curtis syndrome)
Chronic inflammation of the conjunctiva leading to blindness
o It can cause distortion of the eyelids – the eyelashes become misdirected and turn in
o It is transmitted by contact with individuals that carries the organism from an infected
eye, or by flies
Trachoma
A sexually transmitted disease and has multisystem involvement
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o A small painless ulcer or papule appears initially and nodules (buboes) develop after
several weeks
o Fret‘s test – intradermal skin test
Lymphogranuloma Venereum (LGV
It is characterized by copious discharge from the eye, an inflamed and swollen
conjunctiva, and the presence of large inclusion bodies in the host cell cytoplasm
o Usually affects infants
Inclusion conjunctivitis
Genus specific antigen can be detected by this methd
Used to diagnose LGV but not trachoma, inclusion conjunctivitis and
neonatal infection
Single point titer > 1:64
Complement fixation
Used for type-specific antibodies of C. trachomatis
Can be used for diagnosis of LGV, trachoma, inclusion conjunctivitis and
neonatal infection
IgM titer of 1:32
Microimmunofluorescence assay (Micro-IF)
RAtio of single point titer
> 1:64
Ratio of IgM titer
1:32
Etiologic agent of psittacosis/ornithosis
Chlamydophila (formerly Chlamydia) psittaci
Endemic pathogen of all bird species – parrots, parakeets, chicken, ducks
Chlamydophila (formerly Chlamydia) psittaci
Outbreaks have occurred among turkey-processing workers and pigeon aficionados
- Humans acquire the disease by inhalation of infected aerosols form dried bird excreta or
handling of infected birds
- only laboratories with biosafety level 3 facilities can perform cultivation of samples
Chlamydophila (formerly Chlamydia) psittaci
widely used serologic test to detect psittacosis
. complement fixation
sensitive method
Direct Microimmunofluorescence
identity and distinguish all 9
chlamydial species including C. psittaci
Amplification of rDNA using PCR followed by RFLP
human pathogen
- transmission is by aerosol droplets via the respiratory route
- “pear -shaped” appearance of EB; has round and dense inclusions
Chlamydophila (formerly chlamydia) pneumoniae (TWAR strain)
resistant to sulfonamides
- negative for glycogen staining of inclusion bodies
- uses HL of Hep-2 cell lines for culture
Chlamydophila (formerly chlamydia) pneumoniae (TWAR strain)
