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Flashcards in Bacteriology 3 Deck (22):
1

Spirochetes

morphology
BLT species
microscopy

spiral shaped bacteria with axial filaments

Borrelia, Leptospira, Treponema
Borrelia - analine dye
Treponema - Dark Field microscopy

2

Borrelia burgdorferi - Lyme Disease

tranmission & reservoir
region
Stage 1
Stage 2 - FACE
Stage 3

tx

ixodes tick (anaplasma & babesia), mouse reservoir
NE USA

Stage 1 - early localized
- erythema migrans (bulls eye)
- flu like sx
Stage 2 - early disseminated
F - facial nerve palsy/Bell's b/l
A - arthritis, transient & migratory myalgias
C - Cardiac block
E - erythema migrans ("bull's eye")
- CN VII palsy - Bell's palsy
Stage 3 - late disseminated
- chronic arthritis
- encephalopathy

tx: doxycycline
preg women & children - amoxicillin & cefuroxime

3

Leptospira interrogans
morphology
found where?
Leptospirosis
Weil Disease

hook shaped ends
water contaminated with animal urine

Leptospirosis p/w surfers & tropics
- flu like sx
- myalgias of calves
- jaundice
- photophobia w/ conjunctival suffusion (erythema w/o exudate)

Weil Disease - Icterohemorrhagic leptospirosis
- fever
- hemorrhage & anemia
- severe jaundice & azotemia (kidney & liver dysfunction)




4

Syphilis

Treponema pallidum

5

Primary Syphilis

painless chancre - localized dx
VDRL + in ~80%

6

Secondary Syphilis +/- latent syphilis
VDRL/RPR?

disseminated disease p/w
- constitutional sx
- LAD
- patchy hair loss
- maculopapular rash (palms & soles)
- condylomata lata (white warts on genitals)

VDRL/RPR nonspecific
FTA-ABS to confirm

Latent syphilis (+ serology w/o sx) may follow

7

Tertiary Syphilis
Neurosyphilis test?

p/w
- Gummas
- Aortitis (vaso vasorum degeneration, storke/dissection w/o HTN)
- neurosyphilis w/ tabes dorsalis (p/w +romberg sign)
- Argyll Robertson pupil (accomodates but doesn't react)
- Charcot joint

test spinal fluid with VDRL/RPR, FTA-ABS, PCR

8

Congenital Syphilis
when does transmission occure

P/w
Facial Abnl
- rhagades (linear scars at the angle of the mouth)
- snuffles (nasal d/c)
- saddle nose
- notched teeth (Hutchison)
- mulberry molars
- short maxilla
- saber shins
- CN VIII deafness

transmission across placenta after 1st trimester

9

False Positive VDRL

Positive VDRL
P - Pregnancy
V - viral dx (EBV, hepatits)
D - Drugs
R - Rheumatic fever
L - Lupus & Leprosy

detects nonspecific ab to beef cardiolipin

10

Jarisch-Herxheimer reaction

flu-like syndromes
2/2 killed bacteria usually spirochetes releasing toxins

11

Gardnerella vaginalis
Morphology
p/w
dx
tx

pleomophic gram variable rod

p/w BV (grey d/c, nonpainful, fishy smell) a/w sexual activity NOT STI

Clue cells - vaginal epithelial cells covered in G. vaginalis
positive amine KOH whiff test

Clindamycin or metronidazole

12

Chlamydiae
Pathogenesis

Obligate intracellular (can't make ATP)
2 forms cause mucosal infections:
- elementary bodies - endocytosis into cell to form into reticulate body
- reticulate body replicated in cell via fission & reorganizes into elementary bodies

13

Chlamydia trachomatis
Chlamydia pneumoniae & Chlamydophila psittaci
dx
tx

Reactive arthritis,
nongonococcal urethritis & PID
neonatal and follicular adult conjunctivitis

atypical PNA; psittaci has avian reservoir

PCR, NAAT
reticulate bodies seen on stain

Azithromycin (one time dose for mucosal infxn)
Or doxycycline

14

Chlamydia trachomatis serotypes

A,B,C
D-K
L1,L2,L3 (tx)

A,B,C
Africa, Blindness, Chronic Infxn (follicular conjunctivitis)

D-K
urethritis/PID
neonatal PNA (staccato cough) w/ eosinphilia
neonatal conjunctivitis 1-2wk s/p birth

L1, L2, L3
Lymphogranuloma venereum
= small, painless on genitals --> swollen, painless inguinal LNs that ulcerate (buboes)
tx doxycycline

15

RIckettsial Disease & Vector Bourne Illness
Rash Common
- Rickettsia rickettsii
- Rickettsia typhi
- Rickettsia prowazekii
Rash Rare
- Ehrlichia
- Anaplasma
- Coxiella burnetii

tx

RMSF
Typhus
Ehrlichiosis
Anaplasmosis
Q fever

tx - doxycycline
preg - chloramphenicol

16

Rickettsia rickettsii
Vector
Region
p/w

Rocky Mountain Spotted Fever
tick
South Atlantic, esp North Carolina
Triad: Fever, H/A, Rash (writs & ankles --> trunk, palms, soles)

17

Rickettsia typhi
vector
p/w

fleas, endemic
p/w rash centrally -->spreads; spares palms & soles

18

Rickettsia prowazekii

human body louse, epidemic
p/w rash centrally --> spreads; spares palms & soles

19

Ehrlichia
Vector
microscopy

tick
monocytes w/ morulae (mulberry like inclusions in cytoplasm)

20

Anaplasmosis

tick
granulocytes w/ morulae

21

Coxiella burnetii - Q fever
transmission
p/w

no arthropod vector
spores inhaled as endospores from cattle/sheep amniotic fluid

PNA, Cx neg endocarditis

22

Mycoplasma pneumoniae
morphology
p/w
labs
growth medium
tx

pleomorphic, no gram stain (no cell wall)
membrane contains sterols

walking PNA, usually <30 yrs, military recruits and prisons

cold agglutinins (IgM)

Eaton agar

macrolides, doxycycline, or fluoroquinolone