Acute and chronic TKA infection Diagnosis

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Acute and chronic TKA infectionDiagnosis

• Stukenborg-Colsman C, Ostermeier S, Callies T
• Orthopaedic Department
• Hannover Medical School
• Germany

SFB 599
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Epidemiology
Weinstein, Healthcare Epidemiology 2001
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Epidemiology
Implant associated Infection

• Devasting complication with
• High morbidity
• Substantial cost 50.000 (conservative
  estimation)
• Absence of randomised prospective long term
  follow-up
• Based on personal experience and tradition

Mohr V, Spiegel, 2004 Wodtke J et al, Orthopade,
2008 Herbert CK et al, Clin Orthop, 1996
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Epidemiology

• Implant associated infections (TKA within the
  first 2 years)
• lt 1 in hip and shoulder
• lt2 in knees
• lt9 in elbow, but probably underestimated 1
• Implant associated infection after revision
  surgery
• up to 40
• Incidence rate (per prosthesis-years)
• 5.9 per 1000 prosthesis years first 2 years after
  implantation 2
• 2.3 per 1000 prosthesis years during the
  following 8 years
• Further increase
• Better detecting methods
• Growing number of implantations in ageing
  population
• Longer survival rate of prosthesis

1 Tamparuz et, CORR, 2005 2 Steckelberg JM,
Am Soc Microbiol, 2000
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Materials
Epidemiology
Weinstein, Healthcare Epidemiology 2001
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Epidemiology
Commenly identified microorganism causing
prosthetic joint infection
Trampuz A et Zimmerli W, Drugs 2006
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Epidemiology
Time
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41
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Early and delayed usually aquired during
implantation of prosthesis Late predominantly
aquired by haematogenous seeding Sources of
bacteremia are Resiratory tract, skin, dental,
urinary tract infection
Trampuz A et Zimmerli W, Drugs 2006 Zimmerli W, N
Engl J Med, 2004 Giulieri SG, Infection, 2004
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Implant related infection
Epidemiology

• DEFINITION
• (Mirra JM et al. CORR 1982)
• An abscess or sinus tract to joint space
• Positive preoperative aspiration culture
• 2 or more positive intraoperative cultures
• 1 positive intraoperative culture with
  corresponding intracapsular purulence or abnormal
  histology

• Low-Grade-Infection
• Biofilm associated
• Bakteria with changed phaenotype can not be
  cultured
• Some or none planktonic cells in the joint fluid
• Often no clinical signs of infection, because of
  low inflammatory activity

Problem
1 one out of four!
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Biofilm
Costerton, Science 1999
Staphylococcus epidermidis a planktonic form (35
min) b sessile form (20h)
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Diagnosis
Goal Infection is diagnosed (or excluded) before
surgery!
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Diagnosis
Operating condition for sample harvest (room,
clothing, desinfection etc.) If possible no use
of local anaesthetics EDTA cytology of
synovial fluid Rapid transport to lab (telefone
call) Do not wash-out the joint with
additional fluid (minimizes the number of
bacteria) Documentation Paediatric blood
culture bottle Antimicrobial therapy
discontinued 2 weeks before No swap culture of
the joint fluid (minimizes the number of
bacteria) Experienced labaratory
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
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Diagnosis
Every early prosthetic loosening should be under
suspicion of a LOW-GRADE-INFETION
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
Time of implantation lt 2 years. Delayed
infection Early infection in clinical
history Delayed wound healing at time of primary
implantation Joint fluid effusion (planktonic
bacteria) Risk factors Immunsuppression,
Diabetes, Rheumatoid arthritis, obesity etc.
May be absent
Classic signs of infection Early
(acute) Delayed (low grade) Acute onsett of
pain implant loosening Joint fluid
effusion persistend joint pain Warmth at the
implant site Erythema S. aureus, Gram neg.
bacilli Coagulase neg staphylococci
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Diagnosis
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
C-reactive protein (CRP) Sedimentation rate
(ESR) White blood cell count (WBC)
Most important Screening Test
Parvizi J et al. CORR, 2008 N 296, infected
116, noninfected 180 Mean ESR and CRP of infected
group 85 mm/h, CRP 110 mg/l was significantly
higher as in the noninfected group 20 mm/h , 7
mg/l But 4 of infected patients had normal
values
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Diagnosis
Culture of wound or sinus tract (sensitivity
44) Culture of joint fluid 45-100
(sensitivity 60 - 86 2) (Paediatric blood
culture bottle increases!) Synovial-fluid
leukocyte and neutrophil count of 1700
leukocyte/µl, 64 neutrophils Sensitivity for
infection 94 and 98 Specificity 88 and 98
2 Paediatric blood culture bottle
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
highest sensitivity and specificity
2 Parvizi J et al CORR, 2008
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Diagnosis
Radiographs Bone Scintigraphy Leukocyte
Scintigraphy (accuracy of 81) 99mTc-Recombinant
Human Annexin V 1 (N7 Pat. 4 true-positive, 2
true-negative, 1 false-positive, and no
false-negative) PET-CT (specificity
55) FDG PET-CT
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis

• Synovialitis
• Synovialitis tibial loosening
• Synosialitis septic femoral loosening 2

1 Lorberboym J et al. Nukl Med 2009 2 Manthey
N et al. Nukl Med Com 2002
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Diagnosis
PET-CT FDG PET-CT
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
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Diagnosis
Periprosthethic tissue for histopathological
study Highest sensitivity and specificity - 94
1 Classification after Morawietz 2006 2 Typ
I - periprothetic membrane wear type Typ II -
periprothetic membrane infected type Typ III -
periprothetic membrane wear and infected type
(Mixed type) Typ IV - periprothetic membrane
indifferent type
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
1 Müller M et al. J Orth Sur Res 2008 2
Morawietz et al. Pathologe 2006
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Diagnosis
Swab culture Low sensitivity should be
avoided Gram staining synovial fluid and
periprosthetic tissue Low sensitivity lt 26, high
specificity gt97 Culture of synovial
fluid Sensitivity 60,8 1 88,4 3 Cultures
of periprosthetic tissue (at least 3
samples) Sensitivity 65-94 Antimicrobial
therapy discontinued 2 weeks before Microbiologic
al examination up to 14 days
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
1 Trampuz, A et al. N Engl J Med 2007 2
Parvizi J et al CORR 2008 3 Esteban J et al. J
Clin Microbiol 2008
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Diagnosis
Culture of synovial fluid
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
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Diagnosis
Diagnosis of low grade Sonication of removed
prosthesis Sensitivity 78,5 1 to 94,1
3 PCR (polymerase chain reaction) after
sonication or culture of implant surface e.g.
against 16s RNA (in all bacterias)
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
Kobayashi N et al. CORR 2008 Comparison of PCR,
culture, histology PCR 12 additional positive
culture to culture Histology 20 of theses cases
also positive for infection
1 Trampuz, A et al. N Engl J Med 2007 2
Parvizi J et al CORR 2008 3 Esteban J et al. J
Clin Microbiol 2008
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Diagnosis
Direct colouring of the implant surface low
specificity
Clinical history Clinical exam Serologic
tests Fluid aspiration Imaging Histology Micr
obiology Prosthesis
Casereport in vivo
In vitro
Stoodley p et al. JBJS 2008 und 2005
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Summary

• Lab -
• C-reactive protein (CRP), Sedimentation rate
  (ESR), White blood cell count (WBC)
• Most important screening tests
• Joint fluid
• Synovial-fluid leukocyte and neutrophil count -
  98
• Highest sensitivity and specificity
• Imaging
• Leukocyte Scintigraphy (accuracy of 81)
• Histology
• Periprosthethic tissue 94
• Microbiology
• Cultures of periprosthetic tissue (at least 3
  samples)
• Sensitivity 65-94
• PCR promising

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Thank you