Lymphocyte Subset Ratio Cannot Diagnose Immune Failure of a TKA

Area of Science:

• Orthopedic Surgery
• Immunology
• Biomaterials Science

Background:

• Up to 20% of total knee arthroplasty (TKA) patients experience dissatisfaction, often due to pain or stiffness.
• Immune reactions to prosthetics are a potential cause, but diagnostic criteria for TKA immune failure are lacking.
• Histologic evaluation is proposed to identify allergic reactions as a cause of TKA failure.

Purpose of the Study:

• To investigate if lymphocyte subsets in periprosthetic tissues can diagnose immune failure in total knee arthroplasty (TKA).
• To compare immunohistochemical findings of CD4+ and CD8+ lymphocytes with lymphocyte transformation testing (LTT) status for Nickel (Ni).

Main Methods:

• Analysis of periprosthetic tissues from 18 revision TKA cases with aseptic loosening.
• Immunohistochemical staining for CD4+ and CD8+ lymphocytes in biopsies.
• Comparison of lymphocyte subset data with LTT results for Ni and periprosthetic histology.

Main Results:

• No correlation was found between LTT status and CD4+ cells/hpf or the CD4+:CD8+ lymphocyte ratio.
• No relationship existed between LTT stimulation index and the CD4+:CD8+ ratio or the aseptic lymphocyte-dominant vasculitis-associated lesion (ALVAL) score.
• Lymphocyte counts and ratios in periprosthetic tissue were highly variable and unrelated to LTT results or ALVAL score.

Conclusions:

• Lymphocyte subsets in periprosthetic tissue cannot diagnose TKA immune failure on a case-by-case basis.
• Further research is required to establish diagnostic criteria for TKA immune failure.