Chlamydia and Chlamydophila Flashcards
Describe the life cycle of C. trachomatis, C. pneumoniae, and C. psittaci
- Rugged Elementary bodies (EB) are endocytosed.
- Endosome does NOT fuse with lysossome
- EB unpacks into Reticulate Body (RB)
- RB replicates via binary fission
- RBs reorganize to EBs
- C. pneum and C. trachomatis reverse endocytosis
- C. psittaci lyses cell
What useful immune mechanisms prevent chlamydia reinfection?
There are none. Reinfection is common.
What are the C. trachomatis serovars and their respective infections?
- A, B, Ba, C - Blinding trachoma
- L1-L3 - Lymphogranuloma venereum
- D-K - genital tract infection
Where is blinding trachoma typically seen?
In sub-Saharan Africa
Where is Lymphogranuloma venereum endemic?
South and Central America
What is the typical lesion caused by lymphogranuloma venereum?
Small, painless ulcer that proceeds to swollen, painful lyph nodes (buboe)
Which sex is typically a reservoir for chlamydia?
Males
What serious condition can genital chlamydia progress to in women?
PID
What is Reiter Syndrome?
Reactive Arthritis caused by several infections (inlcuding chlamydia) defined by conjuncitivitis, urethritis, and arthritis
What is the antigen typically associated with reactive arthritis?
Leukocyte antigen (HLA-B27)
Describe the procedure for Chlamydia lab Dx
- Physical typically sufficient for Dx
- Cytology (uscopy)
- Cell culture
- Detection of Chlamydial rRNA with DNA probe
How is the Chlamydia cell culture performed.
When is it recommended that to always do a cell culture?
MUST be grown w/i cells
ALWAYS culture if case has legal implications
What is the first choice Tx for Chlamydia? Why?
Doxycycline or azithromycin because C. is intracellular (these ABs can access bug w/i cells)
When is doxycycline contraindicated for C. Tx?
In pregnancy or <9 yo
When a patient treated for C. returns with recurrence of Syx, what is the likely reason?
Reinfection from the partner
