Osteomyelitis

Question 1

Acute hematogenous Osteomyelitis

Answer 1

metaphysis of long bones, vessels don’t have phagocytic cells so bacteria can get there and spread

Pain at site, fevers, Metaphysis

Question 2

Chronic

Answer 2

affected bone becomes necrotic and seperates (sequesterum)
prolonged fevers, weight loss
Surgery needed

Question 3

Thrombosis

Answer 3

Thrombosis allows bacteria colonies to grow and stay there, biofilm can form and make it difficult to penetrate, sequestrum forms which is dead bony island, and abscess has now formed where it is difficult for antibodies to get there

Question 4

Osteomyelitis due to Hematogenous

Answer 4

1-20 or 50+ year old, long bones/vertebrae, bacteremia/trauma,

Staph aureus is main (clusters, coag/catalse postive) , acute pain then chronic when new bone is forming and can cause drainage,

fever/tenderness/swelling/limited motion,

diagnose lab CBC high WBC/CPR/sed rate,

MRI best,

biopsy for culture and PCR test (definitive diagnosis)

Question 5

Osteomyeltis due to secondary contigous focus of infection

Answer 5

50+ years old, femur/tibia/skull/mandible, surgery or soft tissue infection, Staph aureus most common but often mixed, acute recurrent drainage with sinus tract formation, fever/erythema/swelling/heat persistence, diagnosis by probing bone, CBC/CPR/sed rate, bone scan/CT, biopsy is definitive

Question 6

Osteomyelitis fue to vascular insufficency

Answer 6

diabetic foot, 50+ years old, DM or vascular disease, feet, mixed bacteria with antibiotics not allowing spread but not killing them, acute and recurrent drainage/ulceration, pain/swelling/erythema/drainage/ulceration, diagnose with probe to bone, MRI, CBC/CPR/sed rate, biopsy is best

Question 7

Film

Answer 7

Plain film needs 50-75% lost to see bone change, involucrum is new bone forming over sequestrum bone, bone scanning gets osteoblast activity with low specificity but getting test 10-14 days before plain film with lots of false positive, Indium-III Leukocyte scan is more specific for infection and depends on the blood supply so could get false negative, cannot tell infection vs soft tissue, if you combine the last two it helps you a lot, CT gives good 3D picture and good for sequestrum, MRI is more definitive and shows it earlier

Question 8

Treat

Answer 8

acute antibiotics, chronic needs antibiotic and surgery to remove dead tissue and possible revascularization, some chance of amputation

Question 9

Vertebral Osteomyelitis

Answer 9

older individual, chronic UTI, can extend into epidural papsis to paralysis, need MRI, need biopsu cultures

Question 10

Microbiological Studies

Answer 10

chronic sinus tract less than 50% show the pathogen, need bone biopsy to identify pathogen