Background: Plasmablastic lymphoma (PL) is a relatively new category of lymphoma, which has been considered to be found predominantly in the oral cavity and has a strong association with HIV. Case: We report a case of extraoral/mesenteric PL detected using cytological examination of ascitic fluid assisted by flow cytometric (FC) analysis. The cells were positive for CD38, CD138, CD10, CD45 and CD56 and negative for CD3, CD19, CD20 and CD79a, with cytoplasmic lambda light-chain restriction. We also reviewed 67 cases of extraoral PL from the available literature and found them to be less often associated with HIV (than oral PL), occurring mostly in males aged 30-60 years, with the most common extraoral site being the anorectal region. Conclusion: A high index of suspicion at the level of the cytopathologist is imperative for identifying lymphoma cells in a body fluid. A rare entity like PL can also be diagnosed on cytology assisted by ancillary techniques (like FC), without the need for a biopsy. We also suggest that the minimum panel to diagnose PLs should include CD138, MUM-1, Ki-67, ALK-1, CD3, immunoglobulin light-chains, CD20 and PAX5.

Histocompatibility testing is pivotal in any renal transplantation workup, aimed at enhancing prospective donor recipient compatibility and improving transplant outcomes. The evolution and advancement of histocompatibility testing, particularly HLA typing, have significantly improved its precision. This study outlines the historical progression from serologic to DNA-based HLA typing, emphasizing the role of HLA proteins in immune response. Anti-HLA antibodies, targeting HLA proteins, pose challenges in renal transplantation. Monitoring and managing these antibodies are critical for renal transplant success. Complement-dependent cytotoxicity crossmatch and flow cytometry crossmatch are essential techniques for assessing donor–recipient compatibility. Panel-reactive antibody assesses antibodies against a panel of donor antigens, often HLA. Higher PRA levels (percentage) complicate donor matching, requiring specialized protocols. Virtual crossmatch evaluates recipient anti-HLA antibodies against potential donors through synthetic beads. This approach predicts crossmatch outcomes by comparing antibody profiles, offering a valuable tool for the risk assessment of renal transplantation. Despite advancements, a comprehensive understanding of alloreactive immune responses requires a combination of assays, emphasizing the importance of a multifaceted approach in histocompatibility testing. This is an attempt to compile the relevant information, providing a basis for comparison in a clear and foundational format for histocompatibility testing laboratories.

Antibody-mediated rejection is a critical factor in acute and chronic allograft rejection, with Human Leukocyte Antigen as the primary target of the humoral immune response in kidney transplants. In addition to HLA antibodies, non-HLA Abs also play a significant role in AMR. These non-HLA Abs, which can target either autoantigens or alloantigens, may be present pre-transplantation or develop post-transplant. They are associated with various types of allograft injury. The major non-HLA Abs include those directed against the angiotensin II type 1 receptor, endothelin type A receptor, and MICA, as well as other antigens such as vimentin, collagens, and anti-endothelial cell antibodies. Factors such as ischemia, reperfusion injury, and calcineurin inhibitor toxicity can trigger the pathogenic activity of these Abs. The mechanisms underlying non-HLA Ab production are not yet fully understood but are thought to involve endothelial injury and the exposure of neoantigens. Research indicates that these non-HLA Abs can cause graft injury through both complement-dependent and complement-independent pathways. However, detecting non-HLA Abs remains a challenge due to the lack of reliable diagnostic tools. Current treatment strategies for managing the effects of pathogenic non-HLA Abs include intravenous immunoglobulin, plasmapheresis, rituximab, and bortezomib. Early identification of high-risk patients and timely intervention are crucial to preventing graft failure. This review examines the development, mechanisms, and clinical significance of non-HLA Abs in kidney transplantation, highlighting the need for improved diagnostic methods and tailored therapeutic approaches.

J Indian Prosthodont Soc, Official publication of Indian Prosthodontic Society