Immune thrombocytopenia (ITP) is an acquired antibody-mediated disease, for which splenectomy remains a curative treatment. We analyzed histology and phenotypes of ITP-splenectomy specimens from 41 adult patients, with different previous ITP-specific treatments, including B-cell-depleting rituximab (RTX) or not, in an attempt to predict splenectomy success or failure on the basis of day 56 postoperative platelet counts. RTX-naive ITP-spleen samples, compared with those from a 20-patient control trauma cohort, contained the following nonspecific, ITP-evocative, white-pulp lesions: follicular helper T-cell (programmed death-1 and inducible T-cell COStimulator) expansion in reactive follicles (P=0.01 and 0.03, respectively) and regulatory T-cell (FOXP3) expansion in the T-cell zone (P=0.049). On comparing ITP-splenectomy samples that would be successful with those that would be failures, only marginal zone hyperplasia differed (P=0.017). Indeed, 13/21 (61.9%) successful splenectomy samples exhibited marginal zone hyperplasia, as opposed to 1/9 (11.1%) failed splenectomy specimens. RTX impact on ITP-splenectomy samples was characterized by white-pulp (P=0.03) and marginal zone atrophies (P=0.01), and periarteriolar T-cell-zone hyperplasia (P<0.0001). The results of this novel comparative study of the histologic patterns of 41 ITP patients' evocative splenic lesions enabled clear description of different ITP morphologies and phenotypes, as a function of prior treatment and splenectomy success or failure.

Histologic and phenotypic analyses of splenectomy samples from 17 patients with common variable immunodeficiency (CVID) showed the following nonspecific, evocative, white-pulp lesions: white-pulp hyperplasia (WPH) with reactive follicles, giant follicles (GFs), marginal zone hyperplasia, periarteriolar T-zone hyperplasia (PATH) and/or granulomas, which enabled us to discern 2 groups: the first (n=6) composed of WPH with reactive follicles without granulomas, and the second (n=9) characterized by the presence of granulomas with or without WPH. All specimens were Epstein-Barr virus negative by in situ hybridization. Molecular analyses revealed a polyclonal immunoglobulin heavy chain gene (IGH) rearrangement (n=12). WPH-only patients were mostly female individuals and younger at CVID onset, diagnosis, and splenectomy, but their interval between the first symptom and diagnosis was longer; they had more associated infectious events, autoimmune disease, pulmonary complications, and liver regenerative nodular hyperplasia; their IgG, IgA, and IgM concentrations were also higher. Granuloma-group patients were mostly male individuals; were older at CVID onset, diagnosis, and splenectomy; had disseminated granulomatous disease, but infectious events, autoimmune disease, pulmonary complications, and liver regenerative nodular hyperplasia were less common; their immunoglobulin concentrations were lower. Histologic comparisons between the WPH-only and granuloma groups showed more intense WPH and more intense marginal zone hyperplasia and fewer GFs in the former versus more developed PATH and more common GFs in the latter. The results of this novel comparative study of the histologic patterns of 17 CVID patients' evocative splenic lesions suggested different biological and clinical profiles.

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