Chlamydia, Rickettsia, and Intracellular Obligates Flashcards
What are three obligate intracellular pathogens?
Chlamydia, Rickettsia, and Mycobacterium leprae
What are the cell walls like of intracellular pathogens?
bacteria-like cell walls similar to gram neg bacteria
What is are the host/vectors for Chlamydia?
mammals and birds
NOT arthropods
note: rickettsia uses arthropods
What is the difference between Chlamydia and Chlamydophilia?
They are similar, but officially two different genus
Chlamydia psittacosis and Chlamydia pneumoniae are in the Chlamydophilia genus
Chlamydia Trachomatis is in the Chlamydia genus
Why is Chlamydia an obligate intracellular pathogen?
Chlamydia cannot make ATP
Depends on host ATP
There are two stages of developmental cycle…
What are Elementary Bodies?
What are Initial Bodies aka Reticulate Bodies?
EB: small, non-replicating, has cell wall; responsible for transmission from cell to cell or host to host
IB aka RB: large, replicating, no cell wall; non-infectious
What is the intracellular growth cycle?
See also page N-2 for schema.
EB causes endocytosis.
Changes to IB/RB.
Replicates and forms EB.
EB exits cell.
How many serotypes and what illnesses are caused by…
Chlamydophilia psittaci?
Chlamydophila pneumoniae?
Chlamydia trachomatis?
Chlamydophilia psittaci: one serotype causes psittacosis
Chlamydophila pneumoniae: one serotype causes pneumonia in adults
Chlamydia Trachomatis: many serotypes cause Trachoma, Lymphogranuloma Venereum, Conjunctivitis, Infant Pneumonia, Urethritis
What are the features of psittaci?
Generalized infection.
Headache and fever.
Interstitial pneumonia is most severe sign.
What is the relationship between birds and humans for Chlamydophilia psittaci?
Infection caused by inhaling bird poop, commonly by people exposed to rearing birds (parrots through turkeys)
Causes birds to have “Constant Fecal Excretion”
Why is Chlamydophilia pneumoniae important clinically?
Responsible for 10% of adult pneumonias
may play a role in coronary atherosclerosis
How is Chlamydophilia pneumoniae transmitted?
person to person via respiratory aerosols
No birds involved
What are the four major illnesses caused by Chlamydia trachomatis?
Nongonococcal Urethritis (serotypes D-K) Inclusion Conjunctivitis and Infant Pneumonia (serotypes D-K) Trachoma (serotypes A, B, C) Lymophogranuloma Venereum (serotypes L1, L2, L3)
What is the most common venereal disease?
Nongonococcal Urethritis
Are there differences between male and female Nongonococcal Urethritis infection?
How are couples Tx?
Both are commonly assymptomatic.
Symptomatic males present with purulent urethral discharge and epididumitis
Females have growth on the cervix and fallopian tubes… can result in sterility or ectopic pregnancy
Both partners must be treated regardless of symptoms
What is the relationship between Chlamydia and AIDS?
Chlamydia increases AIDS transmission
When are infants exposed to Chlamydia?
Transmitted by an infected mother, regardless of mother’s symptoms
What illnesses does Chlamydia cause in infants and children?
Inclusion Conjunctivitis
Infant pneumonia
What is Inclusion Conjunctivitis?
In whom is it seen?
How is it transmitted?
Conjunctivitis with inclusion bodies like seen with virus.
Mother to infant.
Children can infect each other at pools.
Adolescents and adults can infect each other as an STD.
What is the limitation of antibiotics to prevent or treat transmission of Chlamydia in infants or young children?
What antibiotics are usually used?
Erythromycin and Sulfonamides do no prevent inclusion conjunctivitis.
They do prevent neonatal gonococcal conjunctivitis
How is Trachoma transmitted?
By touch. Ex…
Finger to eye.
Flies to humans.
Where is Trachoma prevalent?
Tropical arid areas.
What is a sequelae of Trachoma?
Chronic reinfection causes infolding of the eyelashes and can lead to corneal scarring and blindness.