Exam 1: Osteomyelitis
Infectious arthritis: Antimicrobial Treatment in Gonococcal infection
-Ceftriaxone 1 gm/day x 7-10 days -Oral amoxicillin or doxycycline (after C&S known)
Management of MRSA Osteomyelitis-CHILDREN --> Alternatives
-Daptomycin 6 mg/kg/dose IV daily -Linezolid 600 mg PO/IV BID for children ≥ 12 years old and 10 mg/kg/dose q8hr for children < 12 years old
Infectious arthritis: Antimicrobial Treatment in Children > 5 years and adults
-Penicillinase-resistant penicillin -Vancomycin if MRSA
Infectious arthritis Organisms by Age Group: Adolescents & adults (18-30 yrs)
-S. aureus -Neisseria gonorrhoeae
Infectious arthritis Organisms by Age Group: Children <5 years
-S. aureus -Streptococcus -Kingella kingae
Infectious arthritis Organisms by Age Group: Neonates
-S. aureus -Streptococcus -gram-negatives
Infectious arthritis Organisms by Age Group: Elderly
-S. aureus -gram-negatives -S. epidermidis
Role of Oral Antibiotics in Osteomyelitis:
-Usually indicated after 2 weeks of IV therapy in moderate infections -May be first line therapy in mild infections Empiric, outpatient therapy
Clinical Practice Guidelines for Management of MRSA Infectious Arthritis-CHILDREN
3-4 week course of therapy Same antibiotics as osteomyelitis
Empiric Treatment of Acute Osteomyelitis --> Risk of Salmonella
3rd generation cephalosporin
The specific duration of antibiotic therapy needed in the management of osteomyelitis is usually ____________
4 to 6 weeks
Optimal Duration of Treatment for MRSA Osteomyelitis in children
4-6 week course is recommended
Individuals at greatest risk for long-term sequelae are those who have symptoms present for more than ________ before starting therapy and those with infections occurring within the hip joint and infections caused by gram-negative organisms.
7 days
__________ osteomyelitis describes infections of recent onset, usually several days to 1 week
Acute
Children and elderly- Children: tibia, femur, humerus, fibula Adults > 50 years of age: vertebral
Acute Hematogenous Osteomyelitis
Local inflammation + systemic symptoms
Acute Hematogenous Osteomyelitis
Infectious arthritis Clinical Presentation
Acute systemic infection Fever, chills, malaise Painful, hot, swollen joint ↑ WBC ↑ ESR (erythrocyte sedimentation rate) Positive blood culture 50% of patients
Oral Alternatives: Extended spectrum penicillin or 3rd generation cephalosporin
Amoxicillin/clavulanate
Infectious arthritis: Diagnosis
Aspiration of joint fluid X-ray MRI
Disease-specific Organisms: Anaerobic bacteria
Bites, diabetic foot ulcer
_______________ is generally the more sensitive marker of response to therapy and often increases and decreases before the ESR
C-reactive protein
________ is generally the more sensitive marker of response to therapy and often increases and decreases before the ESR.
CRP
Empiric Treatment of Acute Osteomyelitis: IV first generation cephalosporin
Cefazolin
Empiric Treatment of Acute Osteomyelitis --> Risk of Pseudomonas
Ceftazidime or cefepime + aminoglycoside
Oral Alternatives: Cefazolin
Cephalexin
Clinical signs > 30 days Open bone injury Necrotic bone
Chronic Osteomyelitis
Risk Factors for infectious arthritis
Chronic illness Rheumatoid arthritis Joint trauma/surgery Joint prosthesis Decreased cellular immunity IV drug use Systemic corticosteroid use
It is recommended that when ______________ is used to treat osteomyelitis with mixed etiologies that include S. aureus, it should be combined with an antistaphylococcal drug such as dicloxacillin, cephalexin, or clindamycin.
Ciprofloxacin
______________ also has poor coverage against anaerobic organisms and staphylococci and emergence of resistant P. aeruginosa can be a problem
Ciprofloxacin
________________ is effective in the treatment of osteomyelitis caused by gram-negative bacteria, such as Enterobacter cloacae and Serratia marcescens; however, many strains of streptococci are relatively resistant
Ciprofloxacin
Empiric Treatment Algorithm for Osteomyelitis --> Local CA-MRSA resistance ≥ 10% AND local clindamycin resistance < 10%
Clindamycin (plus ceftriaxone if K. kingae suspected)
Management of MRSA Osteomyelitis-CHILDREN --> IF: stable with no bacteremia or intravascular infection AND IF: resistance rate is low (<10%)
Clindamycin 10-13 mg/kg/dose IV q6-8hr
Most prevalent Adults > 50 years of age Open fracture, surgery, prosthetics Afebrile, local pain and swelling Positive aspirate
Contiguous Osteomyelitis
_____________ can result from pressure ulcers or from adjacent soft tissue infections and most often involves the distal extremities.
Contiguous osteomyelitis
Monitoring Parameters:
Culture and sensitivity results Clinical signs of inflammation WBC ESR Compliance of outpatient therapy
Device-related Osteoarticular Infections (MRSA) --> Unstable implants, late-onset infections, or long duration of symptoms (>3 weeks)
Debridement + device removal
_____________ infections are typically polymicrobial involving aerobic and anaerobic organisms
Diabetic foot
Oral Alternatives: Nafcillin or oxacillin
Dicloxacillin
Cierny-Mader Staging System for Osteomyelitis - Stage 4:
Diffuse
Clinical Practice Guidelines for Management of MRSA Infectious Arthritis-ADULTS
Drainage or debridement should always be performed 3-4 week course of therapy Treat with same antibiotics as for osteomyelitis
Disease-specific Organisms: Staph epidermidis
Foreign body
Osteomyelitis Organism Isolation - Infants < 1 year
Group B streptococci, S. aureus, E. coli
Disease-specific Organisms: Bartonella henselae
HIV, kitten exposure
_________________ almost always involves one bone whereas contiguous *osteomyelitis* can present in multiple bones, especially when vascular insufficiency is an underlying risk factor.
Hematogenous osteomyelitis
____________________ is typically a disease of the growing bone in children and most cases occur in patients younger than 16 years of age
Hematogenous osteomyelitis
Cierny-Mader Staging System for Osteomyelitis - *A*
Host is healthy
Disease-specific Organisms: Pasturella multocida
Human or animal bite
_______________ require coverage for P. aeruginosa, and therefore, combination therapy with an aminoglycoside, fluoroquinolone, or anti-pseudomonal cephalosporin is needed.
IV drug abusers
Osteomyelitis in the ____________ patient has unique features. More than 50% of such infections involve the vertebral column and less than 20% of infections are located in either the sternoarticular or pelvic girdle.
IV drug user
Disease-specific Organisms: Fungi
Immunocompromised
Disease-specific Organisms: Enterobacteriaceae/PSA
Immunocompromised (P. aeruginosa-puncture wound to foot)
Pros/Cons of IV Antibiotics: *Cons*
Increased cost Patient inconvenience Risk of catheter-related complications: Infection Thrombophlebitis Malfunction
-50% gonococcal in US -gonococcal infxn are associated w/ polyarthritis
Infectious arthritis
Most common clinical presentation: Immobility of joint, no point of tenderness
Infectious arthritis
____________________ can result by spread from an adjacent bone infection, direct contamination of the joint space, or hematogenous dissemination (most common)
Infectious arthritis
Common site of infectious arthritis in adults:
Knee
Signs of infectious arthritis:
Knee joint pain, tenderness, swelling Markedly ↓ ROM
*Oral* Antibiotics for MRSA Infections in Children
Linezolid Clindamycin
Cierny-Mader Staging System for Osteomyelitis - *Bls*
Local and systemic host compromised
Cierny-Mader Staging System for Osteomyelitis - *Bl*
Local host compromised
Cierny-Mader Staging System for Osteomyelitis - Stage 3:
Localized
________ is much better treated with nafcillin than vanco
MSSA
Cierny-Mader Staging System for Osteomyelitis - Systemic Factors
Malnutrition Renal failure Hepatic failure Diabetes Immunosuppression
Cierny-Mader Staging System for Osteomyelitis - Stage 1:
Medullary
Optimal Duration of Treatment for MRSA Osteomyelitis in Adults
Minimum 8-week course of therapy Additional 1-3 months may be considered with oral rifampin-based combination therapy
Infectious arthritis: Antimicrobial Treatment in children <5 years
Nafcillin or cefazolin (if H. flu imm.) Ampicillin or cefuroxime (if no H. flu immunization)
Empiric Treatment of Acute Osteomyelitis: IV antistaphylococcal antibiotic
Nafcillin or oxacillin
Empiric Treatment Algorithm for Osteomyelitis --> Local CA-MRSA resistance < 10%
Nafcillin/oxacillin or cefazolin
___________ may have infectious arthritis because of a broad range of organisms, with S. aureus, group B Streptococcus, and gram-negative organisms being most common
Neonates
_____________________ is almost always monoarticular. The knee is the most commonly involved joint, but infections also can occur in the shoulder, wrist, hip, ankle, interphalangeal joints, and elbow joints.
Nongonococcal bacterial arthritis
Acute Hematogenous Osteomyelitis -- Usually only _________ infecting organism
ONE
Most common clinical presentation: Pain and tenderness of infected area
Osteomyelitis
Contiguous Osteomyelitis - Puncture wounds of the feet are commonly caused by _______________
P. aeruginosa
______________ is the most frequent organism in IV drug abusers
P. aeruginosa
_______________________ should be initiated and continued until there has been a resolution in the erythema, swelling, and tenderness and until the patient is afebrile.
Parenteral antibiotic therapy
Infectious arthritis: Antimicrobial Treatment in IV drug use
Penicillinase-resistant penicillin + aminoglycoside
Infectious arthritis: Antimicrobial Treatment in neonates
Penicillinase-resistant penicillin + aminoglycoside
Pros/Cons of IV Antibiotics: *Pro's*
Potential for better compliance Superior serum levels for some antibiotics Greater historical experience
____________________ is useful in identifying the focus of osteomyelitis
Radionuclide bone scanning
Device-related Osteoarticular Infections (MRSA) --> Oral therapy for 3 months (hips) or 6 months (knees)
Rifampin + FQ, TMP/SMX, tetracycline, or clindamycin
Contiguous-spread disease has several important differences compared with hematogenous osteomyelitis. _____________ is still the most common organism isolated, and infections with multiple organisms, including gram-negative bacilli, occur frequently.
S. aureus
Chronic Osteomyelitis - Pathogens
S. aureus, S. epidermidis P. aeruginosa, E. coli, S. marcescens
Osteomyelitis Organism Isolation - Children > 5 years
S. aureus, Streptococcus pyogenes
Osteomyelitis Organism Isolation - Children 1-5 years old
S. aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Kingella kingae
Contiguous Osteomyelitis - Organisms
S. aureus, Streptococcus, S. epidermidis Gram negative rods Anaerobes
Patients with sickle cell anemia and related hemoglobinopathies are unique in that two thirds of bone infections in these patients are caused by __________ species, while the rest are usually caused by staphylococci and other gram-negative organisms.
Salmonella
Device-related Osteoarticular Infections (MRSA) --> Early onset (< 2 months post surgery) with a short duration of symptoms (≤ 3 weeks) AND debridement with device retention
Same antibiotics as osteomyelitis + rifampin 600 mg daily for 2 weeks
_____________ is most prevalent in children and the elderly.
Septic arthritis
Disease-specific Organisms: Salmonella
Sickle Cell disease
Osteomyelitis Organism Isolation - Adults
Staph epidermidis, S. aureus, P. aeruginosa, Serratia marcescens, E. coli
The bacteriology of hematogenous osteomyelitis is unique in that one pathogen, ______________________, is responsible for more than 80% of these infections,
Staphylococcus aureus
Acute Hematogenous Osteomyelitis: Organisms
Staphylococcus aureus Streptococci Gram negative rods
Infectious arthritis organism: Caused by Prosthetic joint infections
Staphylococcus epidermidis
Cierny-Mader Staging System for Osteomyelitis - Stage 2:
Superficial
Additional Therapies for Osteomyelitis:
Surgical debridement Antibiotic bead therapy Hyperbaric oxygen therapy
Cierny-Mader Staging System for Osteomyelitis - *Bs*
Systemic host compromised
*Oral* Antibiotics for MRSA Infections in Adults
TMP-SMX 4 mg/kg/dose (TMP component) BID + rifampin 600 mg Qday Linezolid 600 mg BID Clindamycin 600 mg q8hr Fluoroquinolone + rifampin Doxycycline/minocycline + rifampin
Despite the seriousness of osteomyelitis, often there are few laboratory abnormalities including;
The erythrocyte sedimentation rate (ESR), C-reactive protein, and WBC count
Empiric Treatment Algorithm for Osteomyelitis --> Local CA-MRSA resistance ≥ 10% AND local clindamycin resistance > 10%
Vancomycin (plus ceftriaxone if K. kingae suspected)
Empiric Treatment of Acute Osteomyelitis --> Allergy to penicillin or concern for CA-MRSA
Vancomycin or Clindamycin
Cierny-Mader Staging System for Osteomyelitis - Local Factors
Venous stasis Major vessel compromise Arteritis Scarring Neuropathy
Acute Hematogenous Osteomyelitis -___________: Staph, E. coli (sec. to urinary infxn), and Mycobacterium tuberculosis
Vertebral
In ___________________ the lumbar and thoracic regions are the locations of most infections and occurs most commonly in adults 50 to 60 years of age.
Vertebral osteomyelitis
___________________ produces nonspecific symptoms, such as constant back pain, fever or night sweats, and weight loss
Vertebral osteomyelitis
Infectious arthritis: use _________ if sensitive H. flu, *cefuroxime* if resistant H. flu
ampicillin
Predisposing factors in patients who have ____________ osteomyelitis include vascular disease, bites, contiguous infections, peripheral neuropathy, hematogenous spread, and trauma
anaerobic
Approximately one third of patients with ______________ have a poor joint outcome, such as severe functional deterioration.
bacterial arthritis
S. aureus, the single most common infecting organism, is found in 37% to 65% of cases of nongonococcal ________________
bacterial arthritis
Diagnosis: gold standard is __________ to determine etiology, but limited due to lack of uniform specimen collection and previous antibiotic use
biopsy
For patients with established vascular insufficiency, if anaerobes are suspected, an antianaerobic cephalosporin (e.g., _____________) or _____________ plus *ceftazidime* can be substituted.
cefoxitin, clindamycin
For patients with established vascular insufficiency need S. aureus, Streptococcus, anaerobes, and gram-negative coverage, Broad-spectrum therapy with a penicillinase-resistant penicillin in combination with _____________ is the preferred initial therapy.
ceftazidime
Bone infections in adults with a history of IV drug abuse require coverage for gram-negative organisms; therefore, empirical treatment with ___________ or ____________ 2 g IV every 8 hours.
ceftazidime or defepime
Osteomyelitis in patients with sickle cell hemoglobinopathies is commonly caused by either Salmonella or S. aureus. Thus, empirical antibiotics of first choice include _______________ or _______________
ceftriaxone or cefotaxime.
if the infection is located within the vertebrae, E. coli must be considered, and depending on the culture and susceptibility data, a switch to a ______________ may be needed.
cephalosporin
In children older than 5 years of age and in adults with *infectious arthritis*, initial therapy with a penicillinase-resistant penicillin or first-generation cephalosporin is appropriate to provide the necessary coverage against S. aureus. Therapy should be changed to ___________, ______________, or ______________ if the S. aureus is resistant to methicillin.
clindamycin, vancomycin, or linezolid
With _____________-spread osteomyelitis there is often an area of localized tenderness, warmth, edema, and erythema over the infected site.
contiguous
Patients with peripheral vascular disease are at risk for the development of ________________
contiguous osteomyelitis
The anaerobic infections in association with _____________ almost always occur within the feet. Bacteroides fragilis and Bacteroides melaninogenicus comprise the majority of anaerobic isolates
diabetes mellitus
In ___________________ that may have osteomyelitis, bone infections are most common in patients with foot ulcers greater than 3 mm and in patients with C-reactive protein levels greater than 3.2 mg/dL (32 mg/L).
diabetic patients
Children responding to initial parenteral therapy may be excellent candidates to receive follow-up oral therapy with an agents such as ________________________ depending on their culture and susceptibility results
dicloxacillin, cephalexin, clindamycin, or amoxicillin
Ampicillin may need to be added to the regimen to provide coverage against ______________
enterococci.
_______________ should not be used in children younger than 16 to 18 years of age or in pregnant women because of the potential to cause cartilage damage.
fluoroquinolones
In *infectious arthritis* disseminated _______________ infections often respond quickly to antibiotics. *Ceftriaxone* 1 g/day for 7 to 10 days is the treatment of choice for adults
gonococcal
Osteomyelitis resulting from puncture injuries to the feet are associated with ________________ infection or the bone and cartilage (sometimes classified as osteochondritis), especially infections caused by P. aeruginosa.
gram-negative
For children 5 years of age or younger, S. aureus and ______________ are the most common infecting organisms
group A streptococci
Infectious arthritis usually is acquired by _____________ spread
hematogenous
Infectious arthritis usually is acquired by _______________ spread
hematogenous
Approximately 50% of patients with ________________ will have positive blood cultures and may obviate the need for bone aspiration in these patients.
hematogenous osteomyelitis
The bacteriology of ________________________ is unique in that one pathogen, Staphylococcus aureus, is responsible for more than 80% of these infections, with group A Streptococci and Streptococcus pneumoniae accounting for a few cases. Kingella kingae, an organism that is part of the oral flora is emerging as a pathogen in children less than 3 years of age.
hematogenous osteomyelitis
Closed needle aspiration is indicated for all joints except the _____ (=open drainage)
hip
Closed-needle aspiration is recommended for all infected joints except the _____
hip
Common site of infectious arthritis in infants:
hip, hematogenous
In ___________________ some organisms, such as Neisseria gonorrhoeae, are especially likely to infect a joint during bacteremia.
infectious arthritis
Risk factors associated with adult _______________ are systemic corticosteroid use, preexisting arthritis, arthrocentesis, distant infection, diabetes mellitus, trauma, and other diseases
infectious arthritis
The three most important therapeutic maneuvers in the management of ___________________ are appropriate antibiotics, joint drainage, and joint rest.
infectious arthritis
Acute Hematogenous Osteomyelitis - Metaphysis of ____________
long bone
In infants younger than 1 month of age with *infetious arthritis*, the infecting organisms vary widely and empirical therapy thus must provide broad-spectrum coverage. A penicillinase-resistant penicillin such as _______________ plus a third-generation cephalosporin is appropriate.
nafcillin or oxacillin,
For children 5 years of age or younger, S. aureus and group A streptococci are the most common infecting organisms. Appropriate therapy in this age group is _______________ 150 to 200 mg/kg per day IV or ____________ 100 mg/kg per day
nafcillin or oxacillin, cefazolin
For children older than 5 years, S. aureus is the most likely infecting organism, and either _____________ 150 to 200 mg/kg per day IV or _______________ 100 mg/kg per day IV is recommended.
nafcillin or oxacillin, cefazolin
Hematogenous osteomyelitis in adults is caused frequently by S. aureus and thus is treated with 8 to 12 g/day of a penicillinase-resistant penicillin such as ____________ or a first-generation cephalosporin (e.g., __________). *Clindamycin* 2.4 g/day, or *vancomycin* 2 g/day (with normal renal function) can be used in adults allergic to penicillin
nafcillin, cefazolin
bone infections that occur after surgery or from contiguous spread, the required broad-spectrum coverage, ___________ 2 g IV every 4 hours plus ___________ or __________ 2 g IV every 8 hours should be used as initial therapy.
nafcillin, ceftazidime or cefepime
In children younger than 5 years of age with *infectious arthritis* who have been immunized for Hib should receive ___________, ______________, or _____________
nafcillin, oxacillin, or cefazolin
Because S. aureus, group B streptococci, and E. coli are the most common infecting organisms in _____________, an IV dosage of 150 mg/kg per day (given in four divided doses) of *oxacillin* or *nafcillin* plus *cefotaxime* 150 mg/kg per day (given in three to four divided doses) is appropriate
newborns
Patients with _____________________ almost always present with a fever, and 50% of patients have an elevated WBC count
nongonococcal bacterial arthritis
The average initial synovial WBC count is 10 × 103/mm3 (10 × 109/L) or greater in ___________________________
nongonococcal bacterial arthritis
The preferable time to obtain culture material in a patient with a chronic draining sinus is at the time of __________________
open surgical debridement.
Dicloxacillin, cloxacillin, and cephalexin (100 mg/kg per day) are effective _________ agents.
oral
Acute Hematogenous Osteomyelitis -- _____________ blood culture results
positive
Osteomyelitis resulting from ________________ to the feet are associated with gram-negative infection of the bone and cartilage (sometimes classified as osteochondritis), especially infections caused by P. aeruginosa. S. aureus is also a significant pathogen in these patients.
puncture injuries
The presence of _____________ usually indicates the presence of a septic joint.
purulent fluid
The most common form of osteomyelitis is from contiguous spread while that of _____________ is hematogenous spread.
septic arthritis
serum WBC, ESR, and C-reactive protein may not be useful acutely in ____________
septic arthritis
. Osteomyelitis in patients with _______________ may occur in any bone, but it most commonly involves the medullary cavity of long or tubular bones.
sickle cell disease
Children with culture-negative osteomyelitis can be managed as presumed _________________ disease with excellent long-term results.
staphylococcal
Cierny-Mader Staging System for Osteomyelitis - *C*
treatment worse than disease
If patients are allergic to penicillins or cephalosporins or are infected with MRSA, __________, ___________, or ____________ can be used
vancomycin, clindamycin, or linezolid
Osteomyelitis of the ____________ is also acquired hematogenously and occurs most frequently in patients older than 50 years of age
vertebrae
