Clinical Bacteriology II

Question 1

What is the causative microorganism of Lyme Disease and what is the natural reservoir?

Answer 1

Causative microorganism: Borrelia burgdorferi (transmitted in tick)

Natural reservoir: mouse

Question 2

What are the symptoms of Lyme Disease?

Answer 2

Initial symptoms

• erythema chronic migrans (bulls eye rash)
• flu-like symptoms
• +/- facial nerve palsy

Later symptoms

• monoarthritis (large joints)
• migratory polyarthritis
• cardiac (AV nodal block)
• neurologic (encephalopathy, facial nerve palsy, polyneuropathy)

Question 3

What is the treatment for Lyme Disease?

Answer 3

Doxycycline (1st line)

Ceftriaxone (better for neuro Sx)

Question 4

What is the causative microorganism of syphilis?

Answer 4

Treponema pallidum

Question 5

What is the treatment for syphilis infection?

Answer 5

Penicillin G

Question 6

What are the stages of syphilis and what is the characteristic finding in each stage?

Answer 6

Primary syphilis - PAINLESS chancre

Secondary syphilis - systemic constitutional symptoms, maculopapular RASH (palms and soles too)

Tertiary syphilis - GUMMAS, aortitis, neurosyphilis, Argyll Robertson pupil

Question 7

What is the most specific test to detect syphilis infection?

Answer 7

fluorescent treponemal antibody absorption (FTA-ABS)

Question 8

What is a non-specific test to detect syphilis infection? What other diseases or conditions will give a positive result with this test?

Answer 8

VDRL/RPR - tests for beef cardiolipin

VDRL
Viruses (mono, hepatitis)
Drugs
Rheumatic fever
Lupus and Leprosy

Question 9

What are signs of congenital syphilis?

Answer 9

saber shins
saddle nose
CN VIII deafness
Hutchinson teeth
mulberry molars

Question 10

When does transmission of syphilis to the placenta occur?

Answer 10

typically after 1st trimester

Question 11

What is the Jarish-Herxheimer reaction?

Answer 11

flu-like syndrome after antibiotics are started d/ t killed bacteria releasing pyrogens

Question 12

What are symptoms of a Gardnerella vaginalis infection?

Answer 12

BACTERIAL VAGINOSIS

• gray vaginal discharge
• fishy smell*
• nonpainful (vs. vaginitis)

Question 13

Clue cells are found in which infection?

Answer 13

Gardnerella vaginalis infection

Question 14

What is the treatment for bacterial vaginosis?

Answer 14

metronidazole or clindamycin

Question 15

What is the treatment for all Rickettsial diseases and vector-borne illnesses (for the most part…)?

Answer 15

doxycycline

Question 16

Where does Rocky Mountain Spotted Fever typically occur?

Answer 16

South Atlantic states (esp. North Carolina)

Question 17

Rash starting at wrists and ankles –> spreading to trunk, severe HA, and red conjunctivae after a tick bite would indicate what infection?

Answer 17

Rocky Mountain Spotted Fever

Question 18

Palms and soles rash is caused by which microorganisms?

Answer 18

Coxsackievirus A
RMSF
Secondary syphilis

Question 19

Which rickettsial disease is endemic and which is epidemic?

Answer 19

endemic (fleas) - R. typhi

epidemic (louse) - R. prowazekii

Question 20

What is the difference b/t the Rickettsii rash and the typhus rash?

Answer 20

Rickettsii - starts on wRist

Typhus - starts on the Trunk

Question 21

What is the vector for Ehrlichiosis?

Answer 21

tick

Question 22

What is a unique blood smear finding with Ehrlichiosis infection?

Answer 22

morulae (“berry-like” inclusion in the cytoplasm of monocytes)

Question 23

What is the vector for Anaplasmosis?

Answer 23

tick

Question 24

What is a unique blood smear finding with Anaplasmosis?

Answer 24

granulocytes with moralae in cytoplasm

Question 25

How is Q fever transmitted?

Answer 25

tick feces and cattle placenta release spores that are inhaled as aerosols

Question 26

How does Q fever present?

Answer 26

pneumonia

Question 27

What microorganism causes Q fever?

Answer 27

Coxiella burnetii

Question 28

What are the 2 forms of chlamydia and how do they contribute to infection?

Answer 28

1. Elementary body - enters cell via endocytosis and is infectious
2. Reticulate body - replicates in cell by fission

Question 29

What complications are associated with Chlamydia infection?

Answer 29

Reactive arthritis (Reiter Syndrome)
Follicular conjunctivitis
Nongonococcal urethritis
PID

Question 30

What stain is most useful to see Chlamydia?

Answer 30

Giemsa or fluorescent Ab-stained smear

Question 31

What is the treatment for Chlamydia infection?

Answer 31

azithromycin (1st line) or doxycycline

Ceftriaxone - Azithromycin often used together b/c high rate of co-infection with N. gonorrhea

Question 32

Chronic infection causing BLINDNESS d/t follicular conjunctivitis in Africa is associated with what types of chlamydia?

Answer 32

Types A, B, and C

Question 33

Urethritis/PID, ectopic pregnancy, neonatal pneumonia, and neonatal conjunctivitis is associated with what types of chlamydia?

Answer 33

Types D - K

Question 34

Small, painless ulcers on genitals –> swollen, painful inguinal lymph nodes that ulcerate (“buboes”) is associated with what types of chlamydia?

Answer 34

This is a description of Lymphogranuloma Venereum

Types L1, L2 and L3

Question 35

What is the MC causative organism in atypical “walking” pneumonia?

Answer 35

Mycoplasma pneumoniae

Question 36

An infection of mycoplasma pneumoniae will result in a high titer of what protein?

Answer 36

high titer of cold agglutinins (IgM) –> agglutinate or lyse RBCs

Question 37

What agar is mycoplasma pneumoniae grown on?

Answer 37

Eaton agar

Question 38

What is the treatment for mycoplasma pneumoniae infection?

Answer 38

macrolide (1st line)
doxycycline
fluoroquinolone

*penicillin ineffective since Mycoplasma have no cell wall