Misc Disorders Flashcards
(139 cards)
What is osteomyelitis?
Infection of bone and inflammation of fatty tissues
Essentials of osteomyelitis diagnosis
- Fever associated with bone pain and tenderness
- Microbiologic diagnosis often made from blood cultures
- Elevated ESR and CRP common
- Early radiographs typically negative
Cause of osteomyelitis
- Hematogenous spread
- Spread from contiguous site of infection/open wound
- Secondary infection in setting of vascular insufficiency or concomitant neuropathy
Duration of osteomyelitis
- Acute
- Chronic
Pathophysiology of hematogenous spread
- Typically due to bacteremia and begins in medullary canal
Epidemiology of hematogenous spread
- Most common in children
- Male
Where is osteomyelitis due to hematogenous spread most commonly seen in children?
- Metaphysis of long bones
- Hemoglobinopathies such as sickle cell increase risk
Risk factors for hematogenous spread of osteomyelitis in children
- Complicated delivery
- Maternal infection at delivery
- Prematurity
- Indwelling catheters
- Urinary tract anomalies
- Sickle cell
- Immunodeficiency disorders
MC primary site of infections cause osteomyelitis through hematogenous spread
- Urinary tract
- Skin/soft tissue
- Intravascular catheterization sites
- Endocardium
- Dentition
MC organisms in children leading to osteomyelitis through hematogenous spread
- S. aureus (MC)
- Salmonella (sickle cell)
- Group A and B strep
- Strep. pneumo
- E. Coli
- Kingella Kingae (other countries)
Where does osteomyelitis often manifest in adults through hematogenous spread?
Vertebral column (LS > TS > CS)
Risk factors for osteomyelitis due to hematogenous spread in adults
- Age
- IVDU
- Diabetes
- IVs
- Indwelling urinary catheters
MC organisms in adults causing hematogenous spread leading to osteomyelitis
- S. aureus (MC)
- Pseudomonas (IVDU)
- Gram - organisms (elderly)
What is contiguous spread?
Infection traveling from a soft tissue site
Causes of contiguous spread leading to osteomyelitis
- Open fractures/trauma
- Prosthetic devices
- Neurosurgery
- Septic arthritis
Pathophysiology of contiguous spread of osteomyelitis
- Symptoms begin 1 month after inoculation
- Infection inoculates the bony cortex and migrates towards the medullary canal
Who is most at risk for osteomyelitis due to contiguous spread?
Adults
MC organisms causing contiguous spread of osteomyelitis
- S. aureus
- Staph epidermidis
- Streptococcus
- Polymicrobial infections more common for contiguous spread
What causes secondary osteomyelitis due to comorbid conditions?
- Chronic, progressive soft tissue infection of foot or ankle
- Hip and sacrum can be involved
- Most often related to diabetes/diabetic ulcers and vascular insufficiency
- Polymicrobial infections common: s. aureus and B-hemolytic strep MC
Clinical presentation of osteomyelitis
- Gradual onset of symptoms over several days - weeks
- Dull pain at involved site
- +/- worse with movement
- Fever and rigors
- Tenderness
- Warmth
- Erythema
- Swelling on exam
What should be done in osteomyelitis if ulcer present?
Probing for bone
What is the presentation of vertebral involvement of osteomyelitis?
- Slower progression –> 3 weeks - 3 months
- Localized pain and tenderness of involved vertebrae
- Often more than one vertebrae involved including intervertebral disks
- Pain increased with percussion over affected area
- fever in 1/2 of patients
- +/- neurologic symptoms (due to extension of infection leading to spinal epidural abscess)
Presentations of osteomyelitis in nonverbal patients/pediatrics
- Decreased use/movement
- Fussiness
Presentations of hip, pelvis, vertebral involvement of osteomyelitis?
Predominantly pain with few other symptoms