septic arthritis

Question 0

SeA is

Answer 0

monoarticualr

Question 1

septic arthritis is always associated with

Answer 1

true arthritis, inflammation

redness, warmth, swelling, joint effusion always merit consideration of SeA even if proceeded by something else

Question 2

acute SeA

Answer 2

bacterial and viral

Question 3

chronic SeA

Answer 3

lyme disease, mycobacteria, gundal, honoccoal, meningiococal

Question 4

Main cause in children

Answer 4

trauma

Question 5

why do neonates get both SeA and osteomyelitis

Answer 5

the epi plate isnt closed so arterioles connect whole bone

Question 6

eldelry MC is

Answer 6

prostethic joing

Question 7

Mc microbes

Answer 7

s aureous>strep A> g- bacilli

gon in <30 years

Question 8

gram negatives

Answer 8

only in 10% of cases, but worse prognosis than gram _

Question 9

what do you think when you see s aureus and pseudomonas in unsuspected locations

Answer 9

SC and SI joint

Question 10

what makes septic arthritis different from others

Answer 10

discomfort when in resting position

Question 11

fever

Answer 11

about 50/50, but may be low grade/insignif (gono

Question 12

migrating polyarticular

Answer 12

gono

Question 13

look for (on PE)

Answer 13

enlarged proximal LN + original source of infection

Question 14

6 special cases of septic arthritis

Answer 14

gonoccal A
prosthetic joint infection
SeA in children
IVDU
septic sacroilitis
lyme disease

Question 15

tx of gon

Answer 15

ceftriaxone

Question 16

two presentations of gon

Answer 16

group 1- migratory

group 2- monoarticualr

Question 17

migratory gon presents with

Answer 17

tenosynovitis
dermatitis
migratory polyarthritis + gon sx

Question 18

synovial fluid in group 1

Answer 18

cell counts low and culture is often negative

Question 19

blood culture in group 1

Answer 19

positive

Question 20

how do you test in group 1

Answer 20

DNA amplification tests in urethral cervical, rectal, pharyngeal swabs

Question 21

group 2 presents

Answer 21

after the tenosynovitis, dermatitis, and migratory polyarthritis

Question 22

group 2 has settled..

Answer 22

into 1-2 joints

Question 23

synovial fluid in group 2

Answer 23

more purulent and culture is positive

Question 24

blood culture in group 2

Answer 24

negative

Question 25

how do you test for group 2

Answer 25

DNA ampligication to detect it in synovial fluid

Question 26

50% of infected prosthetic joints infected wtih

Answer 26

coagulase negative staph | indolent course

Question 27

dx signs of prostehtic septic arth

Answer 27

joint pain, fever, swelling occurs at rest (diff from other aspetic joint inflam) a pos technectium scan after 8 months with prostehtic aspirate culture *best evidence

Question 28

outcome in SeA in children

Answer 28

usually favorable unless it damages the epiphyseal plate (abscess, necrosis) or vascular supply (avascular necrosis)

Question 29

ultra sound used to

Answer 29

detect joint effusion, aspiration, culture

Question 30

ddx of sea in children

Answer 30

toxic synovitis of hte hip (more common)

Question 31

raises suspicions of drug use

Answer 31

sea in unusual locations (sc joint, si joint, pubic sympgysis, hips, shoulders) infxn with bug other than staph (candida, pseudomonas, serratia)

Question 32

dx septic sacrolitis

Answer 32

hard to dx because cant differentiate between msucle pain, disc, dx, nerve entrapment, etc (presents with fever and back pain worsened with motion, bilateral)

Question 33

best dx of septic sacrolitsi

Answer 33

MRI- shows fluid in SI joint and neraby inflam

Question 34

non-specific diagnostics of septic arth

Answer 34

CBC (mild leuko, only 50% of cases), ESR, blood culture (unless gon)

Question 35

most important exam in diagnostics

Answer 35

synovial fluid - positive culture - wbc count >100K (>85% PMN but PMN + intracellular crystals = gout)

Question 36

floating crystals sometimes seen in

Answer 36

sea

Question 37

synovial fluid protein

Answer 37

increase in SeA but also in other forms of inflammatory arthritis

Question 38

management of sea

Answer 38

antibiotics arthrocentesis daily remove prothesis admit most to hosp

Question 39

cxns of sea

Answer 39

relapse and recurrent aspectic j effusion (post-infectious synovitis) abscess or bursa- need drainage secondary OA can occur- tx with arthroplasty

Question 40

lyme disease is

Answer 40

borrela burgdoferi (transmitted by deerk tick)

Question 41

adult ticks get it from

Answer 41

white tailed deer

Question 42

little ticks get it frm

Answer 42

white footed mouth (90% of human cases are nymphs)

Question 43

chronic cases of lyme have

Answer 43

HLA DRB1 0401 allele or IgG anti outer surface protein

Question 44

early stage lyme

Answer 44

1st month- stage 1-localized bulls eye +/ fever, flu-like sx, neck stifness

Question 45

1/2 of patients wtihs tage 1

Answer 45

do not progress beyond this stage

Question 46

early stage 2

Answer 46

weeks-months; disseminated further spread to skin and lymph nodes migratory evolves to monoarticular (knee is MC) cranial neuropathy (bilateral bells), meningeal irritation, peripheral neuro cv: heart block (less common pericarditis and endocarditis)

Question 47

chronic lyme

Answer 47

``` stage III months-years, persistent disabiling subclinical encephalopathy, encephalomyelitis, peripheral neuropathy myocarditis, pericarditis keratitsi, itis, optic neuritis ```

Question 48

dx in early stage vs late stage

Answer 48

early stage- ecm is enough olate stage- more must be done- culture is slow and usually useless, ELISA as first screen (highly sensitive), but lots of FP, esp with other spitochetes like syph, rocky mt spotted fever, etc, western blot, pcr

Question 49

tx lyme disease

Answer 49

early tx is best, but its when serological tests are least sensitive so you have dx clinically

Question 50

tx adults

Answer 50

doxy

Question 51

tx kids

Answer 51

amoxi

Question 52

tx chronic

Answer 52

ceftriaxone