Lyme disease and reactive arthritis

Question 1

Borrelia characteristics?

Answer 1

lack endotoxin

Question 2

Lyme disease?

Answer 2

caused by Borrelia burgdorferi
transmitted but a tick, has fed on infected deer or mouse, tick can not pass on infection to offspring so must get disease from resevoir (deer/mouse)
disease has similarities to syphilis

Question 3

Ixodes scapularis?

Answer 3

deer tick, primary transmitter of disease to humans
most common form is the nymph stage
several stages (larva, nymph, adult)

Question 4

Incidence of lyme?

Answer 4

northeastern, mid-atlantic, coastal, great lakes
spring and summer
incidence increasing
Connecticut is highest incidence
most cases go unreported

Question 5

Stage I?

Answer 5

localized skin infection, erythema migrans

early flu like symptoms

Question 6

Stage II?

Answer 6

Disseminated infection
debilitating malaise and fatigue
secondary erythema migrans
arthritis, neuro disorder, cardiac disorder

Question 7

Stage III?

Answer 7

presistent infection (months- years)
arthritis, encephalopathy, acrodematitis chronic atrophicans

Question 8

acrodematitis chronic atrophicans?

Answer 8

rash on hands and feet caused by Borrelia afzelii
most common in Europe
similar progression to lyme

Question 9

Virulence factors?

Answer 9

outer surface proteins (Osp) that allow attachment to mammalian cell and extracellular matrix, no endotoxin

after tick initiates feeding on infected host, OspA decreases and OspC increases

Host protease plasmin binds to and becomes activated on bacterial surface

Question 10

Why can a tick be removed within 24 hours and no infection?

Answer 10

takes at least that amount of time for OspA to decrease and OspC to increase and for the host protease plasmin to bind to the bacterial surface and become activated

Question 11

What can undergo extensive variation?

Answer 11

surface exposed protein (VIsE)

Question 12

What allows burgdorferi to persist despite immune response?

Answer 12

it binds to mammalian complement regulatory factors, resist complement mediated lysis/opsonization

can turn on/off many genes that code for outer surface proteins

Question 13

Lab diagnosis Lyme?

Answer 13

serology- antibody titer via ELISA and confirm with Western blot (must do both)
immunoflourescent/peroxidase stain of skin biopsy

Question 14

Treatment and prevention of Lyme?

Answer 14

Doxycycline is DOC
avoid vectors, self check, use DEET
manage vegetation
vaccine current unavilable

Question 15

Relapsing fever?

Answer 15

caused by variety of Borrelia species
trasmit by tick/lice
west US, africa, middle east, southeast asia

Question 16

Clin findings of relapsing fever?

Answer 16

sudden onset
aferbrile for several days-weeks
relapse
must consider malaria and other disease as well

Question 17

Lab diagnosis of relapsing fever?

Answer 17

serological test

exam wright stain

Question 18

treat relapsing fever?

Answer 18

tetracycline, erythomycin

Question 19

Leptospira?

Answer 19

small spirochetes, curved at both ends
Leptospirosis
temperate regions, infects wild and domesticated animals

Question 20

Clinical findings of Leptospirosis?

Answer 20

organism infects CNS, liver, kidney after enter mucus membranes
abrupt onset, followed by short aymptomatic period then chronic stage
fatalities most often from kidney failure

Question 21

Classic patient with Leptospirosis?

Answer 21

hunters who skin animals, patient presents with kidney failure (weak, lethargic, may have heart failure)

Question 22

Diagnosis of Lepto?

Answer 22

sero tests

Question 23

Treat Lepto?

Answer 23

penicillin with 4-5 days of clinical symptoms

Question 24

Prevent Lepto?

Answer 24

avoid contact with animal urine

Question 25

Reactive arthritis?

Answer 25

arises following an infection
cannot be cultured from joint
form of spondyloarthritis

Question 26

Spondyloarthritis?

Answer 26

inflammation at sites where tendons attach to bones

Question 27

Clinical manifest of Reactive arthritis?

Answer 27

asymmetric oligoarthritis 1-4 wks

in 1/2 of pts all symptoms resolve in <6months, most patients 1 yr

Question 28

Preceding infections to reactive?

Answer 28

genital (Chlamydia) or enteric infection (Salmonella, Shigella, Campylobacter, Yersinia, Clostridium difficile)

Question 29

Reiter’ Syndrome?

Answer 29

specific form of reactive arthritis
Chlamydia trachomatis most common
assoicated with HLA-B27 (human lymphocyte antigen)
conjunctivitis (preceeds, usually chlamydia)

Question 30

Things to ask for Reactive/ Reiters?

Answer 30

sex history, GI history
atherocentesis
test HLA-B27

Question 31

Molecular mimicry?

Answer 31

certain microbial peptides are similar to self-peptides, and infection with such microbes will lead to autoimmunity

Question 32

Molecular mimicry of HLA-B27 in reactive?

Answer 32

HLA-B27 is an HLA-B allele of the MHC class I molecules
class I present antigenic peptides to the T cell receptors of CD8 t lymphocytes

Question 33

Treat reactive?

Answer 33

if GI give doxycycline for Chlamydia

if Enteric- no treatment, generally infection has resolved on its own, severity may require it

arthritis- NSAIDS, Glucocorticoids

Question 34

Most common joint for Septic arthritis?

Answer 34

knee joint

Question 35

What is useful to look at in the knee to decifer lyme from septic?

Answer 35

white blood cell count

Question 36

Who is most likely to present with arthritis with Lyme disease?

Answer 36

children

Question 37

Why is it impt to decifer lyme from septic arthritis?

Answer 37

lyme can be treated, septic needs immediate surgery

Question 38

Which group has a fever and hard to bear weight?

Answer 38

Septic arthritis