View source for Septic arthritis

==Background==
*Most important diagnostic consideration in acute joint pain (can destroy joint in days)
*Knee most commonly involved in adults; hip most common in peds 
*Most often seen in ppatients &gt;65yr 
*Most common causative organisms
**<35 y/o ''[[N. gonorrhoeae]]''
**>35 y/o ''[[S. aureus]]''

==Clinical Features==
*Fever 
*Warm, red, painful, swollen joint 
*Decreased range of motion to active and passive movement
*[[Gonococcal]] arthritis
**[[Urethritis]]/[[vaginitis]] may be absent 
**May have prodromal phase:
***Migratory arthritis and tenosynovitis predominate before pain and swelling occurs
***Macularpapular rash or pustules esp on hands/feet may proceed overt arthritis
*Endocarditis should be considered in the presence of 2 or more affected joints

==Differential Diagnosis==
*[[Transient (Toxic) Synovitis]]
*Abscess 
*[[Cellulitis]]
*Primary rheumatologic disorder (i.e. vasculitis) 
*Iatrogenic 
*[[Reactive Arthritis (Poststreptococcal)]]
*Consider if pt has Sickle Cell (fever '''and''' limited joint ROM)
**Osteomyelitis typically has neither

==Diagnosis==
===Work-Up===
*Arthrocentesis with synovial fluid analysis
**Synovial fluid culture only (not 100% sensitive)
*CBC 
*ESR
**Sn 94% (with 15mm/h cut-off)<ref>Hariharan, H, et al. Sensitivity of Erythrocyte Sedimentation Rate and C-reactive Protein for the Exclusion of Septic Arthritis in Emergency Department Patients. J of Emerg Med. 2010; 40(4):428–431. http://dx.doi.org/10.1016/j.jemermed.2010.05.029</ref>
*CRP
**Sn 92% (with 20mg/L cut-off)
*Blood Culture
*Gonorrhea culture (urethral/cervical/pharyngeal/rectal) 
*Imaging
**Helpful for excluding other diagnoses (e.g. trauma, osteo)
*Immunocompromised
**Consider mycobacterial or fungal arthritis
**Leukemia history: predisposed to Aeromonas infections

{{Arthrocentesis diagnostic chart}}

==Management==
===[[Arthrocentesis]]===
*Treatment based on diagnostic studies
===[[Antibiotics]]===
{{Septic Arthritis Antibiotics}}
===Consultation===
*Consult ortho for joint irrigation in OR if joint aspirate is indicative of infection

==Disposition==
*Admit all to ortho

==See Also==
*[[Arthrocentesis]] 
*[[Monoarticular Arthritis]] 
*[[Septic Arthritis (Hip)]] 
*[[Septic Arthritis (Peds)]]
*[[Knee Diagnoses]]

==External Links==
*[http://www.mdcalc.com/kocher-criteria-septic-arthritis/ MDCalc - Kocher Criteria for Septic Arthritis]

== Source ==
 <references/>

[[Category:ID]] [[Category:Ortho]]