chapter 14: spirochetes

Question 1

describe spirochetes

• morphology
• culturing
• genera

how do they move

Answer 1

tiny, gram negative organisms with corkscrew configurations of various types

difficult to culture

3 genera
-treponema sp
borrelia sp
leptospira sp

move in spinning fashion via thin endoflagella called axial filaments

Question 2

2 unique things about spirochetes

Answer 2

surroundd by additional phospholipid rich outer membrane with few exposed proteins (protects against immune system)

axial flagella come out of the ends of spirochete cell wall but run sideways (peripasmic flagella)

Question 3

how do you test and screen for infections of spirochetes

Answer 3

darkfield microscopy

Question 4

treponema pallidum causes

Answer 4

causes STD syphilis

Question 5

primary stage of syphilis

Answer 5

painless chancre

Question 6

secondary stage of syphillis

Answer 6

rash on palms and soles

condyloma latum

• painless wartlike lesion, occurs in warm moist sites like vulva or scrotum
• ulcerates and is extremely contagious

CNS eyes bones kidneys and joints may be involved

Question 7

latent syphillis

Answer 7

25% may relapse and develop secondary stage symptoms again

Question 8

tertiary stage

Answer 8

gummas of skin and bone

• localized granulomatous lesions which necrose and become fibrotic
• painless

cardriovascular (aortic aneurysm)

neurosyphillis

develops over 6-40 years

Question 9

neurosyphillis 5 most common presentations

Answer 9

asymptomatic neurosyphilis (pt normal but CSF has syphilis + test result)

subacute meningitis: pt has fever, stiff neck, headache
-CSF has high lymphocyte count, high protein, low glucose
(most bacteria cause acute meningitis with high neut count and low glucose)

meningovascular symphilis: spirochetes attack blood vessels in brain and meninges

tabes dorsalis
posterior column and dorsal roots of spinal cord affected
-vibratory and proprioception
-loss of reflexes and loss of pain and temp sensations (dorsal root)

general paresis: mental deterioration and psychiatric symptoms

MAST G
-this G gets lucky often so it gets to his head (neurosyph) but he contracts syphillis from all the play

Question 10

argyll-roberston pupil

Answer 10

may be present in both tabes dorsalis and general paresis

-accomadation without reaction to light

Question 11

rule of sixes with syphillis

Answer 11

6 axial filaments
6 week incubation
6 weeks for ulcer to heal
6 weeks after ulcer heals, secondary syphilis develops
6 weeks for secondary syphilis to resolve
66% latent stage patients have resolution
6 years to develop tertirary syphilis

Question 12

congenital syphilis

early congenital syphillis

late congenital syphillis

common presentation

Answer 12

early congenital syphilis: like severe adult secondary syphilis (widespread rash and condyloma latum)

• snuffles
• LN, liver, and spleen enlargement and bone infection common

late congenital syphilis
-similar to adult tertirary syphilis but cardiovascular involvment rare

• eight nerve deafness is common
• saddle nose
• saber shins (bowing of tibia)
• hutchinson’s teeth (upper central incisors widely spaced with central notch in each tooth)
• mulberry molars (molars have too many cusps)

Question 13

how can you test active primary or secondary stages of syphillis

Answer 13

dark field microscopy

Question 14

nonspecific treponemal tests

Answer 14

test for Abs against cardiolipin and lecithin
-VDRL and RPR

-nonspecific bc 1% of adults without syphilis will also have these Abs

Question 15

specific treponemal tests

Answer 15

test for Abs against spirochete itself

FTA-ABS

Question 16

all treponemal subspecies (often called non-venereal) tend to cause ___ and _____ except for ____ which primary manifestation is usually ___

Answer 16

skin ulcers, and gummas of skin

carateum causes skin discoloration

Question 17

jarisch herxheimer phenomenon

Answer 17

pts with syphilis develop acute worsening of symptoms immediately after antibiotics are started

-killed organism releases pyrogen that causes symptoms

Question 18

3 subspeces of treponema pallidum

-stages compared to syphilis causing trep

Answer 18

endemicum
pertenue
carateum

first two stages similar but unlike syphillis do not involve heart or CNS

Question 19

endemicum

disease

where occurs

spread how

Answer 19

endemic syphlis, bejel

ocurs in desert zones of africa and middle east

shared by drinking and eating utensils

Question 20

pertenue

disease

where occurs

spread how

symptoms

Answer 20

yaws

moist tropics

person to person contact with open ulcers

papule appears at initial site and grows over months becoming warlike mother yaw

tertiary lesions often cause significant disficguement of face
(imagine jaws taking bite of persons face)

disfiguring lesions on face destorying bone cart and ksin are called gangosa ( a gang of J(Y)aws)

Question 21

carateum

Answer 21

skin disease limited to rural latin america

papule devlops which expands

secondary eruption of numerous red lesions that turn blue in the sun

within year lesion become depigmented turning white

Question 22

borrelia

size, and viewed how

causes what disease

Answer 22

larger than treponema, view under light microscope with giemsa or wright stains

casuses lyme disease and relapsing fever
-both transmitted by insect vectors

Question 23

Borrelia burgdorferi (lyme disease)

where found, resevoir and transmission

Answer 23

northeast, midwest, and northwest US

ixodes tick transferes borrelia burgdorferi

resevoir is white footed mouse and white tailed deer
-ticks pick up spirochete from these and can spread to humans

Question 24

lyme disease early localized stage

Answer 24

skin lesion at site of tick bite (erythema chronicum migrans) ECM

-along with flulike illness and regional lymphadenopathy

Question 25

lyme disease early disseminated stage

Answer 25

4 organ systems involved: skin heart, NS, joints

skin has multiple ECM lesions now and they are smaller than before

cranial nerve palsies (bells palsy) meningitis, peripheral neuropathy

AV nodal block and myocarditis

Question 26

late stage lyme disease

Answer 26

chronic arthritis

encephalophathy (memory impairment, irritability, somnolence)

Question 27

borrelia recurrentis

Answer 27

relapsing fever

transmitted to humans via body lice (pediculus humanus)

high fever rash, chills, meningeal involvment may follow

-symptoms resolve after 3-6 days, pt is afebrile for about 8 days then it comes back and have similar symptoms for 3-6 days

Question 28

what is the key to relapsing fever with borrelia recurrentis

Answer 28

antigenic variation

Question 29

leptospira

look like

what species

where found

Answer 29

long, thin, aerobic spirochetes

leptospira interrogans

found in urine of dogs, and wild animals

Question 30

2 phases of leptospira interrogans infection

Answer 30

first: bacteria invade blood and casue high temp, headache, malaise, muscle aches
- conjuctiva are red an pt experieces photphobia

second: IgM antibodies appear
- meningismus and elevated white count

Question 31

leptospira interrogans serogroup icterohaemorrhagiae can cause

symptoms

Answer 31

weil’s disease

-jaundice which involves renal failure
-hepatitis with jaundice
mental stat changes
hemorrhage in many organs