PB1085 - The histopathological landscape of synovitis in hemophilic arthropathy

Tuesday, June 25, 2024

13:45 – 14:45 ICT

Room: Exhibition Hall

Presenting Author(s)

Roberta Gualtierotti, PhD

Associate Professor
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy; Università degli Studi di Milano, Department of Pathophysiology and Transplantation, Milan, Italy
Milan, Lombardia, Italy

Co-Author(s)

SS

Silvia Spena

Researcher
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
Milan, Lombardia, Italy
AG

Andrea Giachi

Physician
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center
Milan, Lombardia, Italy
CS

Chiara Suffritti

Researcher
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center
Milan, Lombardia, Italy
Sara Arcudi, MD, PhD

Clinician
Foundation I.R.C.C.S. Ca’ Granda, Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
Milan, Lombardia, Italy
Alessandro Ciavarella

Clinician
Fondazione IRCCS Ca’Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Milan, Italy
Milan, Lombardia, Italy
SS

Simona Maria Siboni

Physician
Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center
Milan, Lombardia, Italy
CP

Carlo Pescia

Physician
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Unit of Anatomic Pathology
Milan, Lombardia, Italy
UG

Umberto Gianelli

Full Professor
Università degli Studi di Milano, Department of Health Sciences, ASST Santi Paolo e Carlo, Anatomic Pathology unit
Milan, Lombardia, Italy
LS

Luigi Solimeno

Physician
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Division of Orthopaedic Surgery and Traumatology
Milan, Lombardia, Italy
Flora Peyvandi, MD, PhD

Full Professor
Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Università degli Studi di Milano, Department of Pathophysiology and Transplantation
Milan, Lombardia, Italy

Background: Recurrent joint bleeding leads to chronic arthropathy in severe hemophilia A and B. Despite the recent introduction of novel therapies and the increased availability of treatments some patients still experience synovitis with subsequent joint damage and pain. A deeper knowledge of the histopathological characteristics of hemophilic synovitis could help personalise management and possibly design targeted treatment.

Aims: We studied the synovial membranes of nine patients undergoing orthopedic joint surgery in order to describe the histopathological alterations and immune infiltration characteristics.

Methods: Synovial membranes were collected during surgery. Hematoxylin-eosin coloration and immunohistochemical analysis were performed. Two synovitis scores (Krenn and Humby scores) currently used for rheumatoid arthritis were applied. Synovial collagen fibrosis was evaluated with Masson trichromic staining. Iron deposits were assessed with Perl’s histochemical stain, graded semiquantitatively and evaluated whether iron deposits were mostly found in the intracellular (mainly siderophages) or extracellular compartment.

Results: Nine patients (six severe, one moderate hemophilia A and two severe hemophilia B; four total knee replacement, one knee arthroscopy, two total ankle replacement, two ankle arthroscopies) aged 41±14 years were included.
All the collected samples displayed synovial hyperplasia and hemosiderin deposits; in seven out of nine a pauci-immune infiltrate was observed, two samples showed a lymphoid-myeloid infiltrate with lymphoid aggregates. Subintimal fibrosis was moderate to severe in eight cases out of nine and mild in one case. Iron deposition was heterogeneous (mild, moderate and severe), mostly in the intracellular compartment with the only one case with mild almost exclusive extracellular deposition.

Conclusion(s): The majority of the samples displayed blood-induced synovial hyperplasia with a pauci-immune infiltrate resembling degenerative arthropathy, whereas lymphoid aggregates usually observed in inflammatory arthritis were less frequent. Larger studies in hemophilic arthropathy at different stages are needed to clarify if a different histopathological landscape may correlate with clinical history and predict the response to different therapeutic approaches.