Download presentation
Presentation is loading. Please wait.
1
Is the lab useful to distinguish Septic Arthritis versus Transient Synovitis? Laboratory rounds Jan 30, 2003 Rob Hall PGY3
2
Case 3yo Refuses to weight bear on left hip No hx of trauma or fever URTI recently T 38.0 Painful ROM right hip Kid looks well What is your differential? What tests would you order? How useful are your tests going to be?
3
Differential of Limp Trauma –fracture, sprain, strain, contusion, abuse Infection –Septic arthritis, osteomyelitis, cellulitis, fascitis, myositis Inflammation –Toxic synovitis, JRA, HSP, serum sickness, rheumatic fever Other –AVN, SCFE, tumor, leukemia, sickle cell
4
Are a wbc, ESR, or CRP useful for distinguishing septic arthritis vs transient synovitis? Small retrospective studies with poor design –Molteni 1978 –McCarthy1980 Potentially meaningful studies –Kunnamo 1987 –Del Beccaro 1992 –Kocher 1999
5
Kunnamo 1987 American Journal of the Diseased Child Prospective study of all kids referred to a tertiary pediatric referral center with arthritis N = 278, only 18 with septic arthritis Gold standard was based on follow up if joint not tapped and no follow up data given
6
Kunnamo 1987 American Journal of the Diseased Child Variable Sensitivity Specificity –CRP > 20 94% 92% –ESR > 20 94% 68% –WBC > 12 59% 95% –T > 38.5 77% 95% –T>38.5 or 100% 87% CRP >20
7
Kunnamo 1987 American Journal of the Diseased Child Small study Method problems Wide confidence intervals –CRP > 20: sensitivity 94% (95%CI 72 – 99%) Doesn’t answer the question
8
Del Beccaro 1992 Annals of Emergency Medicine Retrospective chart review Method problems N = 132 –Septic arthritis 38 –Transient synovitis 94 Gold standard problems –Transient synovitis defined based on clinical course but 13% lost to follow up
9
Del Beccaro 1992 Annals of Emergency Medicine Statistically significant differences –Variable Septic Arthritis Transient synovitis –Temp38.137.2 –ESR 4419 –WBC13.211.2
10
Del Beccaro 1992 Annals of Emergency Medicine VARIABLESENSITIVITYSPECIFICITY ESR > 2079%72% T > 37.566%68% T > 38.045%85% WBC > 1526%84% ESR > 20 and/or Temp > 37.5 97%50%
11
Del Beccaro 1992 Annals of Emergency Medicine Wide confidence intervals Huge overlap between groups with each variable How can we use this information? –ESR, CBC, temp not that helpful in isolation –Combinations may be useful
12
Kocher 1999 Journal of Bone and Joint Surgery Retrospective chart review of 282 patients Same metholodogical problems Found statistical differences b/w septic arthritis and transient synovitis for…… –Hx of fever –Ability to weight bear –Joint effusion on Xray –Temp –ESR –WBC
13
Kocher 1999 Journal of Bone and Joint Surgery Multivariant analysis found four predictors of septic arthritis –History of fever –Non-weight bearing –ESR > 40 –WBC > 12 Developed an algorithm based on above 4 variables
14
Kocher 1999 Journal of Bone and Joint Surgery PredictorsTransient Synovitis Group Septic Arthritis Group Probability of septic arthritis (%) 022%0%0.2% 15413.0% 2191440% 355393% 403099.6%
15
Kocher 1999 Journal of Bone and Joint Surgery This is NOT a validated prediction rule Again suggests that combination of information is useful
16
Approach to the Irritable Hip
17
Surprise! The lab alone is NOT the answer…………
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.