Before arthroplasty

yes

Allergy yes Allergy no

no

No (prophetic) allergy test

Consider “hypoallergenic”implant material

“Standard” implant material

History of hypersensitivity to metalsor potential bone cement

components

Allergy (patch) test with metalsand bone cement components

Flowchart for the evaluation of potential allergy prior to primary arthroplasty (for details, see text)

Flowchart for the evaluation of potential allergy in arthroplasty with complications (for details, see text)

Arthroplasty with complications

no/suspicion of allergy(after exclusion of infection)

Allergy yes

Allergyno

suggestive ofhyper-

sensitivity

otherpathology positive

yes

Plan treatment accordinglyAllergy diagnostics

Patch test Histology

Integrate history, clinical picture and diagnostic findings to verify potential allergy

Detection of “conventional” elicitors

LTT**) Lymphocyte transformation test can be performed in parallel.Until now for scientific purposes,clinical significance has to be evaluated case by case

Clinical Algorithm

© Copyright: Peter Thomas, MD, PhD and Burkhard Summer, PhD, Clinic for Dermatology and Allergology, Ludwig Maximilians-University Munich

His

topa

thol

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al e

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icle

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Red

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dy G

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m

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itio

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ts: P

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Non

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r par

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Mac

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lly d

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che

mic

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echa

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r par

ticl

es B

BR –

© Copyright: Veit Krenn, MD, PhD, Center for Histology, Cytology and Molecular Diagnostics, Trier, Germany

Literature: Krenn V et al. (2014) Histopathologischer Partikelalgorithmus [Histopathological particle algorithm]. Z Rheumatol

73:639–649Krenn V et al. (2013) Update on endoprosthesis pathology: Particle algorithm for particle identification in the

SLIM. Sem Arthroplasty 24:265–275