Maladies de Castleman : épidémiologie, classification et critères diagnostiques

Castleman disease is a group of rare disorders characterized by lymph node enlargement, specific microscopic changes to the lymph nodes, and a broad range of symptoms and laboratory findings. The two main subtypes are unicentric Castleman disease (UCD) and multicentric Castleman disease (MCD). The multicentric subtype can be further classified into two categories: HHV-8 positive multicentric Castleman disease and idiopathic multicentric Castleman disease (iMCD). In the United States (US), the annual incidence of Castleman disease (CD) has been estimated to range from 6500 to 7700 in a 2014 study. Approximately 75 percent were estimated to be unicentric CD and the remaining 25 percent were estimated to be split between HHV-8-associated MCD or HHV-8-negative/idiopathic MCD. Diagnostic criteria for iMCD have been established by an international working group of pediatric and adult pathology and clinical experts. The proposed consensus criteria require characteristic histopathologic findings on lymph node biopsy, enlargement of multiple lymph node regions, the presence of multiple clinical and laboratory abnormalities, and the exclusion of infectious, malignant, and autoimmune disorders that can mimic iMCD. © 2022 Published by Elsevier Masson SAS on behalf of Société nationale française de médecine interne (SNFMI).

A Comprehensive Clinicopathologic and Molecular Study of 19 Primary Effusion Lymphomas in HIV-infected Patients

Primary effusion lymphoma (PEL) is associated with human herpesvirus 8 and frequently with Epstein-Barr virus (EBV). We report here a single-center series of 19 human immunodeficiency virus-associated PELs, including 14 EBV+ and 5 EBV- PELs. The objectives were to describe the clinicopathologic features of PELs, with a focus on programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) expression, to search for genetic alterations by targeted deep sequencing analysis, and to compare the features between EBV+ and EBV- cases. All the patients were male, and the median age at diagnosis was 47 years old (interquartile range: 40 to 56 y). Reflecting the terminal B-cell differentiation, immunophenotypic profiles showed low expression levels of B-cell markers, including CD19 (0/19), CD20 (1/19), CD79a (0/19), PAX5 (1/19), BOB1 (3/19), and OCT2 (4/19), contrasting with a common expression of CD38 (10/19), CD138 (7/19), and IRF4/MUM1 (18/19). We observed a frequent aberrant expression of T-cell markers, especially CD3 (10/19), and less frequently CD2 (2/19), CD4 (3/19), CD5 (1/19), and CD8 (0/19). Only 2 cases were PD-L1 positive on tumor cells and none PD-1 positive. With respect to immune cells, 3 samples tested positive for PD-L1 and 5 for PD-1. Our 36-gene lymphopanel revealed 7 distinct variants in 5/10 PELs, with either a single or 2 mutations per sample: B2M (n=2), CD58 (n=1), EP300 (n=1), TNFAIP3 (n=1), ARID1A (n=1), and TP53 (n=1). Finally, we did not observe any major clinical, pathologic, or immunohistochemical differences between EBV+ and EBV- PELs and the outcome was similar (2-y overall survival probability of 61.9% [95% confidence interval, 31.2-82.1] vs. 60.0% [95% confidence interval, 12.6-88.2], respectively, P=0.62).

Persistent FDG/PET CT uptake in idiopathic retroperitoneal fibrosis helps identifying patients at a higher risk for relapse

BACKGROUND

The aim of this study was to evaluate the prognostic value of persistent retroperitoneal fibrosis FDG uptake using FDG/PET CT in patients with idiopathic retroperitoneal fibrosis (IRF).

METHODS

In this monocentric retrospective cohort study, all patients admitted for IRF from January 2009 to December 2017 underwent a FDG/PET CT at diagnosis and during follow up. Metabolic activity of IRF was assessed by retroperitoneal fibrosis FDG uptake measured as maximal standardized uptake value (SUVmax). The primary outcome was IRF relapse rate during follow-up.

RESULTS

23 consecutive patients (54.7 [36.9-89] years, 73.9% of men) diagnosed with IRF had FDG/PET CT imaging performed at diagnosis, 3.1 [1-8.7] months (i.e 1st evaluation) and 10.4 [4.9-17.5] months (i.e 2nd evaluation) after diagnosis. High FDG retroperitoneal fibrosis uptake was present in all patients at diagnosis (SUVmax 6.5 [3.8-11.9]) and persisted in 16 (69.6%; SUVmax 3.65 [2.1-5.4]) and 12 (52.2%; SUVmax 3.75 [2.7-7.8]) patients, at 1st and 2nd evaluation respectively. All but one patient had received steroids at IRF diagnosis and 21 (91.3%) were in complete remission at both 1st and 2nd evaluation. During a median follow-up period of 38.7 [3-106.9] months, 6 (26.1%) patients suffered IRF relapse that occurred 15.7 [9.2-42.8] months after diagnosis. Multivariate analysis showed that only persistent retroperitoneal fibrosis FDG uptake at 2nd evaluation was associated with IRF relapse (p = .046).

CONCLUSIONS

In IRF, persistent retroperitoneal fibrosis FDG uptake during follow up is associated with clinical outcome. FDG/PET CT may help to better stratify the risk of relapse and target therapy in IRF.

Prognosis of autoimmune hemolytic anemia in critically ill patients

Patients with autoimmune hemolytic anemia (AIHA) may require intensive care unit (ICU) admission. In order to describe the characteristics of AIHA patients in ICU and identify prognosis factors, clinical and biological data from 44 patients admitted in one ICU between 2002 and 2015 were retrospectively analyzed. The main reasons for ICU admission were profound anemia without any organ failure in 19 patients (either for safer transfusion or continuous monitoring only). Twenty-five (57%) patients had a past history of hemopathy. Twenty patients presented with a direct anti-globulin test (DAT) positive for immunoglobulin G (DAT-IgG) only (46%), 8 with a DAT positive for both IgG and complement (DAT-IgG+C) (36%), and 16 with a DAT positive for complement only (DAT-IgG+C) (18%). Corticosteroids and rituximab were administered to respectively 44 (100%) and 12 (25%) patients. Red blood cell transfusion was required in 28 (64%) patients. Ten (23%) patients received vasopressors. Renal replacement therapy was necessary in 14 (31.8%) patients. Thirteen (30%) patients died in the ICU. There was no difference between survivors and non-survivors regarding associated comorbidities like hemopathy (18/31 [58%] vs. 7/13 [54%], p = 0.80). In decedents, age was higher (72 years [57.8-76.3] vs. 50 years [34.3-64], p < 0.01) and organ dysfunctions were more severe at day 1 (SOFA 8 [7-11] vs. 5.5 [3-7], p < 0.01). Patients with a DAT-IgG displayed poorer outcome in comparison with patients with DAT-IgG+C/C (hospital mortality 69% vs. 36%, p = 0.04). Mortality rate of AIHA patients requiring ICU admission is consequential and appears to be impacted by age, organ failures, and DAT-IgG.