Comparative performance analysis of Synovasure™ and Leukocyte Esterase assays for the diagnosis of periprosthetic infections in complex microbiological situations - 12/11/24

Doi : 10.1016/j.otsr.2024.104046

Adrien Pascal ^a,^b,^c,⁎ , Pierre-Jean Lambrey ^a,^b,^c, Benjamin Valentin ^a,^b,^d, Henri Migaud ^a,^b,^c, Sophie Putman ^a,^b,^c, Philippe-Alexandre Faure ^a,^b,^c, Julien Dartus ^a,^b,^c, Caroline Loiez ^a,^b,^e, Benoîtde Saint Vincent ^a,^b,^c, Eric Senneville ^a,^b,^f
^a Centre de Référence Pour le Traitement des Infections Ostéo-Articulaires Complexes (CRIOAC), Avenue du Professeur-Emile-Laine, 59037 Lille-Tourcoing, France
^b Université Lille-Hauts de France, 59000 Lille, France
^c Service de Chirurgie Orthopédique et Traumatologique, CHU de Lille, 2 Avenue Émile Laine, 59000 Lille, France
^d Service de Pharmacie Clinique, Pharmacie, CHU de Lille, 59000 Lille, France
^e Service de Bactériologie-Hygiène, Centre de Biologie-Pathologie, CHU de Lille, 2 Avenue Émile Laine, 59000 Lille, France
^f Service Universitaire des Maladies Infectieuses et du Voyageur, Hôpital Dron, 59200, Tourcoing, France

^⁎Corresponding author at: Service de Chirurgie orthopédique et traumatologique, CHU de Lille, 2 avenue Émile Laine, 59000 Lille, France.Service de Chirurgie orthopédique et traumatologiqueCHU de Lille, 2 avenue Émile LaineLille59000France

Sous presse. Épreuves corrigées par l'auteur. Disponible en ligne depuis le Tuesday 12 November 2024

Abstract

Introduction

Osteoarticular infections (OAI) after prosthetic surgery have serious functional and economic consequences. Rapid tests for alpha-defensin (TAD) and leukocyte esterase (TLE) are two intra-articular markers involved in the diagnosis of OAIs. TLE cannot be applied in the presence of blood unless centrifugation is used, but the rate of "non-application" of the test for this reason is unknown in complex microbiological situations (discordant or negative puncture, ongoing antibiotic treatment). We therefore conducted a prospective study to determine: 1) the performance of the TAD and TLE rapid tests in diagnosing complex OAI, 2) the rate of non-application of the TLE due to hemarthrosis, and 3) the concordance between the two tests.

Assumption

These two diagnostic tests had a negative predictive value (NPV) ≥ 90% for the diagnosis of complex OAI.

Materials and methods

A total of 79 suspected OAI patients with complex microbiological diagnoses were included between 2018 and 2023. They were 52 men (66%) for 27 women (34%), with a mean age of 66 ± 13.5 years. The hip (n = 41, 52%) and knee (n = 36, 46%) were the most represented, followed by the elbow (n = 1, 1%) and shoulder (n = 1, 1%). These patients were suspected of having an OAI that required joint puncture, but with a complex microbiological diagnosis due to discordant punctures (n = 21, 27%) or sterile punctures despite strong suspicion of infection (n = 50, 63%), or in case of ongoing antibiotic treatment (n = 8, 10%). All patients underwent joint fluid puncture followed by TAD (Synovasure™, Zimmer, Warsaw, IN, USA) and, when the macroscopic appearance of the sample allowed (clear fluid group), TLE (Multistix 8SG, Siemens Healthcare GmbH, Erlangen, Germany). The results of both tests were compared with Musculoskeletal Infection Society (MSIS) criteria.

Results

Of the 79 patients included, 27 (34%) were considered infected according to the MSIS. In 30% of cases (n = 24), TLE was not feasible due to the presence of blood in the joint fluid. In the "clear fluid" group, the NPV was equal to 90% for both TAD (sensitivity 87%, specificity 88%) and TLE (sensitivity 87%, specificity 81%). The two parameters showed almost perfect agreement (κ = 0.927).

Conclusion

TAD and TLE are two rapid, reliable tests with near-perfect concordance and high NPV, even in situations of complex microbiological diagnosis. They are particularly useful for deciding on a therapeutic strategy for patients with complex OAI. The TLE cannot be used in 30% of cases due to hemarthrosis, but centrifugation can correct this defect.