Rickettsia, chlamydia, and mycoplasma pneumoniae Flashcards
What is the treatment for all Rickettsial diseases and vector-borne illnesses?
Doxycycline
Causative agent for Rocky Mountain Spotted Fever?
Vector for agent?
Geographical location for RMSF?
Rickettsia rickettsii
Tick
Occurs mostly in Southern Atlantic states, especially North Carolina
RMSF rash progression
starts at wrist and ankles and then spreads to trunk, palms, and soles
Rickettsiae are what kind of organisms?
Require which cofactors (2)? Why?
Rickettsiae are obligate intracellular organisms
Require CoA and NAD+
Cannot synthesize their own ATP
Classic triad associated with RMSF?
Headache
Fever
Rash (caused by vasculitis)
“Palms and soles rash” are usually seen in which in which disease states?
“you drive CARS with your PALMS and SOLES”
Coxsackievirus A
RMSF
Secondary Syphilis
Causative agent of endemic typhus? Vector?
Causative agent of epidemic typhus? Vector?
R. typhi causes ENDEMIC typhus. Fleas.
R. prowazekii causes EPIDEMIC typhus. Human body louse
Where does the rash occur for Rickettsi and Typhus?
“Rickettsii on the wRists…Typhus on the Trunk”
Causative agent for Ehrlichiosis?
Vector?
What to look for on microscopy?
Ehrlichia
Vector is the tick
Look for monocytes with morulae (berry-like inclusions) in the cytoplasm
Causative agent for Anaplasmosis?
Vector?
What to look for on microscopy?
Anaplasma
Vector is the tick
Granulocytes with morulae in cytoplasm
Causative agent for Q fever?
Vector? (this is a trick question)
How is one exposed to the disease?
Coxiella burnetii
No arthropod vector
Tick feces and cattle placenta release spores that are inhaled as aerosols
How does Q fever present?
As pneumonia
What is queer about Q fever?
It has no rash or vector and its causative organism can survive outside in its endospore form
Is chlamydia intracellular or extracellular organism? Why?
Obligate intracellular organism because they cannot make their own ATP
What are the two forms of chlamydia?
Elementary bodies
Reticular bodies
What is an elementary body? What does it look like? And what does it do?
Elementary chlamydia bodies are small, dense, and INFECTIOUS. Enter the cell via Endocytosis.
Transformers into reticular bodies
What is a reticular body? And what does it do?
Replicates in the cell by FISSION. Reorganizes into elementary bodies
Chlamydia trachomatis causes what? (4)
- Reactive arthritis (Reiter syndrome)
- Follicular conjunctivitis
- Nongonococcal urethritis
- PID
C. pneumoniae and C. psittaci cause what? How are they transmitted?
They cause aytpical pneumonia.
Transmitted via aerosols
How to treat chlamydia? 2
Azithromycin–1 time treatment
Doxycycline
What do chlamydia serotypes A, B, and C cause?
Chronic infection &
Blindness due to follicular conjunctivitis
in Africa
ABCs: Africa/Blindness/Chronic infection
What do chlamydia serotypes D-K cause? 4
- Urethitis/PID
- Ectopic pregnancy
- Neonatal pneumonia (staccato cough)
- Neonatal conjunctivitis
Best way to remember chlamydia serotypes D-K?
D-K cause everything else
How is the neonatal disease transmitted?
Passage through infected birth canal
What do chlamydia serotypes L1, L2, and L2 cause?
Lymphogranuloma venereum
What in the hell are Lymphogranuloma venereum? What do they lead to
Small, painless ulcers on the genitals that cause swollen painful lymph nodes that eventually ulcerate.
The ulcerated LNs are known as “buboes”
What does mycoplasma pneumonia cause? How does it present
- Classic cause of atypical “walking pneumonia”
2. Insidious onset with HA, non-productive cough, and patchy or diffuse interstitial infiltrate
How does the x-ray of mycoplasma pneumonia compare to the patient?
On which agar is m. pneumoniae cultured?
- The xray looks worse than the patient does
2. Eaton agar
How does mycoplasma pneumoniae predispose to lysed or aggultinated RBCs?
M. pneumoniae creates a high titer of cold agglutinins (IgM) which can agglutinate or lyse RBCs
What can treat m. pneumoniae? (3) What can’t…and why not? (1)
Macrolide, doxycycline, or flurorquinolone.
PCN ineffective because mycoplasma does not have a cell wall
- Best way to stain m. pneumoniae?
2. What gives the membrane of m. pneumoniae stability
- No cell wall so it doesn’t Gram stain. Use acid fast
2. Membrane contains sterols for stability
M. pneumoniae is common in which patient age?
Frequent outbreaks in what kind of populations? (2)
- Patients
