3: Soft Tissue and Bone

Question 1

Why is it usually not helpful to get a skin culture at the site of infection?

Answer 1

Will be polymicrobial

Question 2

List of DDx to consider when considering septic joint

Answer 2

1. Gonococcal arthritis
2. Gout, pseudogout
3. Trauma
4. RA
5. Rheumatic fever
6. Still’s disease
7. Lyme disease
8. Gonococcal: endocarditis, sarcoidosis, mengingococcemia
9. Reactive arthritis
10. Bleeding into the joint (hemophilia)
11. Sickle cell crisis

Question 3

Two reasons why its tricky to differentiate between crystal arthritis (gout/pseudogout) and septic arthritis

Answer 3

1. Crystal arthritis can have similarly high WBCs and mimics the sx
2. Even if there are crystals in the joint fluid, pts with crystal arthropathy can also develop septic arthritis

Question 4

Some Ddx to consider with osteomyelitis

Answer 4

1. Cellulitis
2. Septic arthritis
3. Gout**
4. Diabetic ulcer
5. Tb bone infection
6. Rheumatic fever
7. Metastatic CA
8. Myeloma
9. AVN

Question 5

Symptoms of Sporotrichosis

Answer 5

Begin 1-12 weeks after infection with progressive symptoms: small/painless bump -> bump gets bigger and looks like open sore -> more bumps near the original one or up the arm

Question 6

Cellulitis on darker skin

Answer 6

May be darkened or even black discoloration

Question 7

Two components of septic shock

Answer 7

1. Critical reduction in tissue perfusion

2. Acute failure of multiple organs

Question 8

Risk factors for soft tissue infections

Answer 8

1. Immunosuppression / chronic illnesses
2. Prior or chronic skin infections (tinea infection, cellulitis, dry skin, edema)
3. Implanted devices (pacemakers, artificial joints)
4. Occupational exposures (zoonoses)

Question 9

Ddx to consider for cellulitis

Answer 9

1. DVT
2. Necrotizing fasciitis
3. Erysipelas
4. Venous stasis
5. Contact dermatitis
6. Underlying osteomyelitis