Case report: Non-EBV associated cerebral vasculitis and cerebral hemorrhage in X-linked lymphoproliferative disease.

X-linked lymphoproliferative disease (XLP) is a rare genetic disorder characterized by immune dysregulation. The three most common clinical phenotypes are EBV-associated infectious mononucleosis (FIM), abnormal gammaglobulinemia, and lymphoma. We present a rare case of XLP1 with neurovasculitis, which is non-EBV-related and involves multiple systems, a condition rarely seen in children. The patient initially presented with an unsteady gait, which progressively evolved into language and consciousness disorders. Additionally, CT scans revealed multiple nodules in the lungs. Subsequent genetic testing and brain tissue biopsy confirmed the diagnosis: XLP1-related cerebral vasculitis and cerebral hemorrhage. Tragically, during the diagnostic process, the child experienced a sudden cerebral hemorrhage and herniation, ultimately resulting in fatality. This case offers a comprehensive insight into XLP1-related cerebral vasculitis and cerebral hemorrhage, underscoring the significance of early diagnosis and prompt treatment, while also imparting valuable clinical experience and lessons to the medical community.

SLAM Family Receptors in B Cell Chronic Lymphoproliferative Disorders.

The signaling lymphocytic activation molecule (SLAM) receptor family (SLAMF) consists of nine glycoproteins that belong to the CD2 superfamily of immunoglobulin (Ig) domain-containing molecules. SLAMF receptors modulate the differentiation and activation of a wide range of immune cells. Individual SLAMF receptors are expressed on the surface of hematopoietic stem cells, hematopoietic progenitor cells, B cells, T cells, NK cells, NKT cells, monocytes, macrophages, dendritic cells, neutrophils, and platelets. The expression of SLAMF receptors was studied during normal B cell maturation. Several SLAMF receptors were also detected in cancer cell lines of B-lymphoid origin and in pathological B cells from patients with B cell chronic lymphoproliferative disorders (B-CLPD), the most frequent hematological malignancies in adults. This review summarizes current knowledge on the expression of SLAMF receptors and their adaptor proteins SAP and EAT-2 in B-CLPD. Several SLAMF receptors could be regarded as potential diagnostic and differential diagnostic markers, prognostic factors, and targets for the development of novel drugs for patients with B-CLPD.

Single-Cell Transcriptomic Analysis of Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis.

Epstein-Barr virus (EBV) infection can lead to infectious mononucleosis (EBV-IM) and, more rarely, EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH), which is characterized by a life-threatening hyperinflammatory cytokine storm with immune dysregulation. Interferon-gamma (IFNγ) has been identified as a critical mediator for primary HLH; however, the detailed role of IFNγ and other cytokines in EBV-HLH is not fully understood. In this study, we used single-cell RNA sequencing to characterize the immune landscape of EBV-HLH and compared it with EBV-IM. Three pediatric patients with EBV-HLH with different backgrounds, one with X-linked lymphoproliferative syndrome type 1 (XLP1), two with chronic active EBV disease (CAEBV), and two patients with EBV-IM were enrolled. The TUBA1B + STMN1 + CD8 + T cell cluster, a responsive proliferating cluster with rich mRNA detection, was explicitly observed in EBV-IM, and the upregulation of SH2D1A-the gene responsible for XLP1-was localized in this cluster. This proliferative cluster was scarcely observed in EBV-HLH cases. In EBV-HLH cases with CAEBV, upregulation of LAG3 was observed in EBV-infected cells, which may be associated with an impaired response by CD8 + T cells. Additionally, genes involved in type I interferon (IFN) signaling were commonly upregulated in each cell fraction of EBV-HLH, and activation of type II IFN signaling was observed in CD4 + T cells, natural killer cells, and monocytes but not in CD8 + T cells in EBV-HLH. In conclusion, impaired responsive proliferation of CD8 + T cells and upregulation of type I IFN signaling were commonly observed in EBV-HLH cases, regardless of the patients' background, indicating the key features of EBV-HLH.

Case report: EBV-related eye orbits and sinuses lymphohistiocytic infiltration responsive to rituximab in a patient with X lymphoproliferative syndrome type 1.

Background and aims: X lymphoproliferative syndrome type 1 (XLP1) is a rare inborn error of immunity due to mutations of SH2D1A, encoding for slam-associated protein (SAP). The clinical phenotype includes severe mononucleosis, hemophagocytic lymphohistiocytosis (HLH), and B-cell lymphomas. Methods: We report the case of a child affected with XLP1 who presented with an incomplete HLH, triggered by Epstein-Barr virus (EBV) and treated with rituximab, involving orbits and paranasal sinuses. Results: The lesion was indistinguishable from lymphoma, complicating diagnosis and treatment. In addition, considering the high incidence of lymphoma in patients with XLP1, histology helped define its nature, driving therapeutic choices. Conclusion: We described an unusual presentation of incomplete HLH in a patient affected with XLP1: an EBV-driven infiltration of the orbits and paranasal sinuses. This led us to a challenging differential diagnosis of lymphoma-associated hemophagocytic syndrome, which can be frequently observed in patients with XLP1. Considering the extremely poor prognosis of this clinical finding, we sought for a prompt diagnosis and managed to obtain it and to immediately establish the right treatment on the basis of the pathological finding.

Effect of pre-emptive rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder in pediatric kidney transplant recipients: A case series from the pediatric nephrology research consortium.

BACKGROUND: There are scant data on the effect of rituximab on EBV DNA levels and prevention of post-transplant lymphoproliferative disorder (PTLD) in pediatric kidney transplant recipients with EBV DNAemia. METHODS: Kidney transplant recipients with EBV DNAemia treated with rituximab to prevent PTLD between 7/1999 and 7/2019 at five pediatric centers were included. Those with confirmed PTLD at the onset of rituximab were excluded. Primary outcomes included percentage change in EBV DNAemia and occurrence of PTLD post rituximab. RESULTS: Twenty-six pediatric kidney transplant recipients were included. Median age at transplant was 4 years (IQR 2.1-10.3). EBV DNA load monitoring by qPCR was performed at 1-3 month intervals. EBV DNAemia onset occurred at a median of 73 days post-transplant (IQR 52-307), followed by DNAemia peak at a median of 268 days (IQR 112-536). Rituximab was administered at a median of 9 days post peak (IQR 0-118). Rituximab regimens varied; median dose 375 mg/m2 (IQR 375-439) weekly for 1-4 doses per course. Following rituximab, EBV DNA load decreased to <10% of baseline at 120 days in 20/26 patients; however, only 30% achieved complete resolution at last follow-up (median 2094 days post-transplant [IQR 1538-3463]). Two (7%) developed PTLD at 915 and 1713 days post rituximab. All recipients had functioning grafts. One death occurred in a child with PTLD following remission due to unrelated reasons. CONCLUSIONS: In the largest pediatric kidney transplant recipient case series with EBV DNAemia given rituximab to prevent PTLD, rituximab achieved a short-term reduction in DNA load; however, recurrent DNAemia is common.

Epstein-Barr virus-associated post-transplant lymphoproliferative disorders in pediatric transplantation: A prospective multicenter study in the United States.

BACKGROUND: Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disorders (PTLD) is the most common malignancy in children after transplant; however, difficulties for early detection may worsen the prognosis. METHODS: The prospective, multicenter, study enrolled 944 children (≤21 years of age). Of these, 872 received liver, heart, kidney, intestinal, or multivisceral transplants in seven US centers between 2014 and 2019 (NCT02182986). In total, 34 pediatric EBV+ PTLD (3.9%) were identified by biopsy. Variables included sex, age, race, ethnicity, transplanted organ, EBV viral load, pre-transplant EBV serology, immunosuppression, response to chemotherapy and rituximab, and histopathological diagnosis. RESULTS: The uni-/multivariable competing risk analyses revealed the combination of EBV-seropositive donor and EBV-naïve recipient (D+R-) was a significant risk factor for PTLD development (sub-hazard ratio: 2.79 [1.34-5.78], p = .006) and EBV DNAemia (2.65 [1.72-4.09], p < .001). Patients with D+R- were significantly more associated with monomorphic/polymorphic PTLD than those with the other combinations (p = .02). Patients with monomorphic/polymorphic PTLD (n = 21) had significantly more EBV DNAemia than non-PTLD patients (p < .001) and an earlier clinical presentation of PTLD than patients with hyperplasias (p < .001), within 6-month post-transplant. Among non-liver transplant recipients, monomorphic/polymorphic PTLD were significantly more frequent than hyperplasias in patients ≥5 years of age at transplant (p = .01). CONCLUSIONS: D+R- is a risk factor for PTLD and EBV DNAemia and associated with the incidence of monomorphic/polymorphic PTLD. Intensive follow-up of EBV viral load within 6-month post-transplant, especially for patients with D+R- and/or non-liver transplant recipients ≥5 years of age at transplant, may help detect monomorphic/polymorphic PTLD early in pediatric transplant.

BCR signaling is required for posttransplant lymphoproliferative disease in immunodeficient mice receiving human B cells.

Posttransplant lymphoproliferative disease (PTLD) is a major therapeutic challenge that has been difficult to study using human cells because of a lack of suitable models for mechanistic characterization. Here, we show that ex vivo-differentiated B cells isolated from a subset of healthy donors can elicit pathologies similar to PTLD when transferred into immunodeficient mice. The primary driver of PTLD-like pathologies were IgM-producing plasmablasts with Epstein-Barr virus (EBV) genomes that expressed genes commonly associated with EBV latency. We show that a small subset of EBV+ peripheral blood-derived B cells expressing self-reactive, nonmutated B cell receptors (BCRs) expand rapidly in culture in the absence of BCR stimulation. Furthermore, we found that in vitro and in vivo expansion of EBV+ plasmablasts required BCR signaling. Last, treatment of immunodeficient mice with the BCR pathway inhibitor, ibrutinib, delays onset of PTLD-like pathologies in vivo. These data have implications for the diagnosis and care of transplant recipients who are at risk of developing PTLD.

Cutaneous lymphoproliferative disorders: Back to the future.

In the 1980s, immunohistochemistry and clonality analyses became instrumental in the recognition and definition of new types of cutaneous T-cell lymphoma (CTCL) and cutaneous B-cell lymphoma (CBCL) and the development of new classifications. By accepting loss of pan-T-cell antigens and clonal T-cell receptor gene rearrangements as important criteria to differentiate between benign and malignant T-cell proliferations, and monotypic immunoglobulin light-chain expression and clonal immunoglobulin gene rearrangements as crucial criteria to distinguish between benign and malignant B-cell proliferations, many cases, until then diagnosed as cutaneous lymphoid hyperplasia or pseudolymphoma, were reclassified as primary cutaneous CD4+ small/medium T-cell lymphoma (PCSM-TCL) or primary cutaneous marginal zone lymphoma (PCMZL), respectively. However, in recent years there is growing awareness that neither these immunohistochemical criteria nor demonstration of T-cell or B-cell clonality is specific for malignant lymphomas. In addition, many studies have reported that these low-grade malignant CTCL and CBCL have an indolent clinical behavior and an excellent prognosis with disease-specific survival rates of or close to 100%. As a result, recent classifications have downgraded several low-grade malignant cutaneous lymphomas to lymphoproliferative disorder (LPD). Both the 5th edition of the WHO classification (2022) and the 2022 International Consensus Classification (ICC) of mature lymphoid neoplasms reclassified PCSM-TCL as primary cutaneous CD4+ small/medium T-cell LPD and primary cutaneous acral CD8+ T-cell lymphoma as primary cutaneous acral CD8+ T cell LPD. While the 2022 ICC introduced the term "primary cutaneous marginal zone LPD," in the 5th edition of the WHO classification PCMZL is maintained. In this review we describe the background and rationale of the continually changing terminology of these conditions and discuss the clinical consequences of downgrading malignant lymphomas to LPDs.

Primary hepatic Castleman disease.

Castleman disease (CD) is a rare, benign lymphoproliferative disorder with characteristic histopathological features, but variable aetiology, presentation, treatment and prognosis. It is broadly classified based on its location and histopathological features, with unicentric hyaline vascular disease presenting most commonly. We present a case of primary, unicentric hepatic CD that was incidentally found on imaging and managed with laparoscopic resection.

A differential diagnosis method for systemic CAEBV and the prospect of EBV-related immune cell markers via flow cytometry.

Chronic active Epstein-Barr virus (CAEBV) infection of the T-cell or Natural killer (NK)-cell type, systemic form (systemic CAEBV or sCAEBV) was defined by the WHO in 2017 as an EBV-related lymphoproliferative disorder and is listed as an EBV-positive T-cell and NK-cell proliferation. The clinical manifestations and prognoses are heterogeneous. This makes systemic CAEBV indistinguishable from other EBV-positive T-cell and NK-cell proliferations. Early diagnosis of systemic CAEBV and early hematopoietic stem cell transplantation can improve patient prognosis. At present, the diagnosis of systemic CAEBV relies mainly on age, clinical manifestations, and cell lineage, incurring missed diagnosis, misdiagnosis, long diagnosis time, and inability to identify high-risk systemic CAEBV early. The diagnostic methods for systemic CAEBV are complicated and lack systematic description. The recent development of diagnostic procedures, including molecular biological and immunological techniques such as flow cytometry, has provided us with the ability to better understand the proliferation of other EBV-positive T cells and NK cells, but there is no definitive review of their value in diagnosing systemic CAEBV. This article summarizes the recent progress in systemic CAEBV differential diagnosis and the prospects of flow cytometry.

Epstein-Barr virus latency patterns in polymorphic lymphoproliferative disorders and lymphomas in immunodeficiency settings: Diagnostic implications.

Epstein-Barr virus (EBV) is responsible for many B cell lymphoproliferative disorders (LPD) spanning subclinical infection to immunodeficiency-related neoplasms. EBV establishes a latent infection in the host B cell as defined histologically by the expression of EBV latent membrane proteins and nuclear antigens. Herein, we characterize the latency patterns of immunodeficiency-related neoplasms including post-transplant lymphoproliferative disorders (PTLD) and therapy-related LPD (formerly iatrogenic) with latent membrane protein-1 (LMP-1) and EBV nuclear antigen-2 (EBNA-2) immunohistochemistry. The latency pattern was correlated with immunodeficiency and dysregulation (IDD) status and time from transplant procedure. 38 cases of EBV+ PTLD in comparison to 27 cases of classic Hodgkin lymphoma (CHL) and diffuse large B cell lymphoma (DLBCL) arising in either the therapy-related immunodeficiency setting (n = 12) or without an identified immunodeficiency (n = 15) were evaluated for EBV-encoded small RNAs by in situ hybridization (EBER-ISH) and for LMP-1 and EBNA-2 by immunohistochemistry. A full spectrum of EBV latency patterns was observed across PTLD in contrast to CHL and DLBCL arising in the therapy-related immunodeficiency setting. Polymorphic-PTLD (12 of 16 cases, 75 %) and DLBCL-PTLD (9 of 11 cases, 82 %) showed the greatest proportion of cases with latency III pattern. Whereas, EBV+ CHL in an immunocompetent patient showed exclusively latency II pattern (13 of 13 cases, 100 %). The majority of EBV+ PTLD occurred by three years of transplant procedure date and were enriched for latency III pattern (21 of 22 cases, 95 %). Immunohistochemical identification of EBV latency by LMP-1 and EBNA-2 can help classify PTLD in comparison to other EBV+ B cell LPD and lymphomas arising in therapy-related immunodeficiency and non-immunodeficiency settings.

Immunogenetic Background of Chronic Lymphoproliferative Disorders in Romanian Patients-Case Control Study.

BACKGROUND AND OBJECTIVES: The implications of the genetic component in the initiation and development of chronic lymphoproliferative disorders have been the subject of intense research efforts. Some of the most important genes involved in the occurrence and evolution of these pathologies are the HLA genes. The aim of this study is to analyze, for the first time, possible associations between chronic lymphoproliferative diseases and certain HLA alleles in the Romanian population. MATERIALS AND METHODS: This study included 38 patients with chronic lymphoproliferative disorders, diagnosed between 2021 and 2022 at Fundeni Clinical Institute, Bucharest, Romania, and 50 healthy controls. HLA class I and class II genes (HLA-A/B/C, HLA-DQB1/DPB1/DRB1) were investigated by doing high resolution genotyping using sequence specific primers (SSP). RESULTS: Several HLA alleles were strongly associated with chronic lymphoproliferative disorders. The most important finding was that the HLA-C*02:02 (p = 0.002, OR = 1.101), and HLA-C*12:02 (p = 0.002, OR = 1.101) have a predisposing role in the development of chronic lymphoproliferative disorders. Moreover, we identified that HLA-A*11:01 (p = 0.01, OR = 0.16), HLA-B*35:02 (p = 0.037, OR = 0.94), HLA-B*81:01 (p = 0.037, OR = 0.94), HLA-C*07:02 (p = 0.036, OR = 0.34), HLA-DRB1*11:01 (p = 0.021, OR = 0.19), and HLA-DRB1*13:02 (p = 0.037, OR = 0.94), alleles have protective roles. CONCLUSIONS: Our study indicates that HLA-C*02:02 and HLA-C*12:02 are positively associated with chronic lymphoproliferative disorders for our Romanian patients while HLA-DRB1*11:01, HLA-DRB1*13:02, and HLA-B*35:02 alleles have a protective role against these diseases.

Interventional treatment of refractory non-traumatic chylous effusions in patients with lymphoproliferative disorders.

To report results of interventional treatment of refractory non-traumatic abdomino-thoracic chylous effusions in patients with lymphoproliferative disorders. 17 patients (10 male; mean age 66.7 years) with lymphoproliferative disorders suffered from non-traumatic chylous effusions (chylothorax n = 11, chylous ascites n = 3, combined abdomino-thoracic effusion n = 3) refractory to chemotherapy and conservative therapy. All underwent x-ray lymphangiography with iodized-oil to evaluate for and at the same time treat lymphatic abnormalities (leakage, chylo-lymphatic reflux with/without obstruction of central drainage). In patients with identifiable active leakage additional lymph-vessel embolization was performed. Resolution of effusions was deemed as clinical success. Lymphangiography showed reflux in 8/17 (47%), leakage in 2/17 (11.8%), combined leakage and reflux in 3/17 (17.6%), lymphatic obstruction in 2/17 (11.8%) and normal findings in 2/17 cases (11.8%). 12/17 patients (70.6%) were treated by lymphangiography alone; 5/17 (29.4%) with leakage received additional embolization (all technically successful). Effusions resolved in 15/17 cases (88.2%); 10/12 (83.3%) resolved after lymphangiography alone and in 5/5 patients (100%) after embolization. Time-to-resolution of leakage was significantly shorter after embolization (within one day in all cases) than lymphangiography (median 9 [range 4-30] days; p = 0.001). There was no recurrence of symptoms or post-interventional complications during follow-up (median 445 [40-1555] days). Interventional-radiological treatment of refractory, non-traumatic lymphoma-induced chylous effusions is safe and effective. Lymphangiography identifies lymphatic abnormalities in the majority of patients and leads to resolution of effusions in > 80% of cases. Active leakage is found in only a third of patients and can be managed by additional embolization.

Post-transplant lymphoproliferative disorders following kidney transplantation: A literature review with updates on risk factors, prognostic indices, screening strategies, treatment and analysis of donor type.

Post-transplant lymphoproliferative disorders (PTLD) is a devastating complication of kidney transplantation with an insidious presentation and potential to disseminate aggressively. This review delineates the risk factors, prognostic indexes, screening, current management algorithm and promising treatment strategies for PTLD. Kidneys from both extended criteria donors (ECD) and living donors (LD) are being increasingly used to expand the donor pool. This review also delineates whether PTLD outcomes vary based on these donor sources. While Epstein-Barr virus (EBV) is a well-known risk factor for PTLD development, the use of T-cell depleting induction agents has been increasingly implicated in aggressive, monomorphic forms of PTLD. Research regarding maintenance therapy is sparse. The international prognostic index seems to be the most validate prognostic tool. Screening for PTLD is controversial, as annual PET-CT is most sensitive but costly, while targeted monitoring of EBV-seronegative patients was more economically feasible, is recommended by the American Society of Transplantation, but is limited to a subset of the population. Other screening strategies such as using Immunoglobulin/T-cell receptor require further validation. A risk-stratified approach is taken in the treatment of PTLD. The first step is the reduction of immunosuppressants, after which rituximab and chemotherapy may be introduced if unsuccessful. Some novel treatments have also shown potential benefit in studies: brentuximab vedotin, chimeric antigen receptor T-cell therapy and EBV-specific cytotoxic T lymphocytes. Analysis of LD v DD recipients show no significant difference in incidence and mortality of PTLD but did reveal a shortened time to development of PTLD from transplant. Analysis of SCD vs ECD recipients show a higher incidence of PTLD in the ECD group, which might be attributed to longer time on dialysis for these patients, age, and the pro-inflammatory nature of these organs. However, incidence of PTLD overall is still extremely low. Efforts should be focused on optimising recipients instead. Minimising the use of T-cell depleting therapy while encouraging research on the effect of new immunosuppressants on PTLD, screening for EBV status are essential, while enabling shared decision-making during counselling when choosing kidney donor types and individualised risk tailoring are strongly advocated.

Epstein-Barr virus associated colitis in kidney transplant patients: a case series.

BACKGROUND: Gastrointestinal complications are common in kidney transplant (KT) patients and can be a consequence of the chronic use of immunosuppression. The differential diagnosis of colitis in KT patients includes intolerance to immunosuppressive agents, namely mycophenolate mofetil, de novo inflammatory bowel disease (IBD) and opportunistic infections. Epstein-Barr virus (EBV) infection may cause post-transplant colitis or trigger de novo IBD, although is seldom thought as the causative pathogen. OBJECTIVES: To describe clinical characteristics, endoscopic and histological findings, treatment and outcome of three patients that developed EBV associated colitis following kidney transplantation. METHODS: We retrospectively analyzed three patients with EBV associated colitis; clinical data including transplantation, gastrointestinal symptoms, endoscopy findings, and follow-up data was obtained. RESULTS: We present a case series of three patients with EBV colitis following KT, with an average age at clinical presentation of 59 years and elapsed time since the KT ranging from five to 22 years. Clinical manifestations included bloody diarrhoea, abdominal pain, weight loss and/or fever. Cytomegalovirus colitis, mycophenolate mofetil-related colitis, lymphoproliferative disease and graft versus host disease were excluded. One patient had a prior diagnosis of IBD. Two of the three patients had an unfavourable outcome with death despite reduction and/or switching of immunosuppressants, optimal medical treatment (including antiviral and intravenous immunoglobulin therapies) and salvage surgical therapy. CONCLUSION: A multidisciplinary approach is necessary to allow an expeditious diagnosis of a rare entity such as EBV associated colitis in KT. Long-term surveillance of these patients and the development of effective and safe therapies is essential.

Risk Factors Associated with PTLD Related Mortality in Adult Multivisceral Transplant Recipients - A Single Centre Cohort Study.

Background: PTLD is a heterogeneous group of lymphoproliferative diseases which can add significant mortality following multivisceral transplantation (MVTx). Our study aimed to identify potential risk factors of mortality in adult MVTx recipients who developed PTLD. Methods: All adult recipients of intestinal-containing grafts transplanted in our institution between 2013 and 2022, and who developed PTLD, were included in the study. Results: PTLD-associated mortality was 28.6% (6/21). Increased relative risk of mortality was associated with Stage 3 ECOG performance score (p=0.005; HR 34.77; 95%CI 2.94-410.91), if the recipients had a splenectomy (p=0.036; HR 14.36; 95%CI 1.19-172.89), or required retransplantation (p=0.039; HR 11.23; 95% CI 1.13-112.12). There was a significant trend for increased risk of PTLD mortality with higher peak EBV load (p=0.008), longer time from MVTx to PTLD diagnosis (p=0.008), and higher donor age (p 0.001). Peak LDH before treatment commencement was significantly higher in the mortality group vs the survival group (520.3 +- 422.8 IU/L vs 321.8 +- 154.4 IU/L; HR 1.00, 95%CI 1.00 to 1.01, p=0.019). Peak viral load prior to treatment initiation (Cycle Threshold (CT) cutoff = 32) correlated with the relative risk of death in MVTx patients who developed PTLD [29.4 (3.5) CTs in survivors compared to 23.0 (4.0) CTs in the mortality group]. Conclusions: This is the first study to identify risk factors for PTLD-associated mortality in an adult MVTx recipient cohort. Validation in larger multicentre studies and subsequent risk stratification according to these risk factors may contribute to better survival in this group of patients.

Iatrogenic immunodeficiency-associated lymphoproliferative disorder presenting as small bowel perforation.

A woman in her late 50s on mycophenolate for limited systemic sclerosis presented with abdominal pain. Vital signs and investigative evaluations were normal. Cross-sectional imaging identified gastric and small bowel wall thickening, free fluid, and pneumoperitoneum. In the operating room, a small bowel perforation was found and resected. Postoperatively, immunosuppression was held and she completed a course of amoxicillin/clavulanate. She discharged home and re-presented on postoperative day 8 with seizures and was found to have a frontal brain mass which was biopsied. Pathology from both the resected bowel and brain biopsy demonstrated Epstein-Barr virus-positive B-cell lymphoproliferative disorder with polymorphic B-cell features. The patient's immunosuppression was discontinued, and she was enrolled in a clinical trial for chemotherapy. Lymphoproliferative disorder can present years after immunosuppression initiation with either spontaneous perforation or solid tumour. Pathological assessment determines treatment options. Heightened concern for atypical clinical presentations in immunosuppressed patients is always warranted.

Stenotrophomonas maltophilia skin infection in an immunocompetent patient: Primary cutaneous CD30+ T-cell lymphoproliferative disorder or pseudolymphoma?

Cutaneous pseudolymphomas are a wide group of diseases mimicking cutaneous lymphoma. They comprise several skin conditions with different etiopathogenesis, clinical-pathological features, and prognosis, which may occur in the absence of an identifiable trigger factor or after administration of medications or vaccinations, tattoos, infections, or arthropod bites. They present with different manifestations: from solitary to regionally clustered lesions, up to generalized distribution and, in rare cases, erythroderma. They persist variably, from weeks to years, and resolve spontaneously or after antibiotics, but may recur in some cases. CD30+ T-cell pseudolymphomas are characterized by the presence of large, activated lymphoid cells, generally in response to viral infections, arthropod assault reactions, and drug eruptions. Stenotrophomonas maltophilia is a ubiquitous Gram-negative bacillus responsible for opportunistic infections in immunocompromised patients. Infection of intact skin in immunocompetent patients is particularly rare. Here, we report a case of a man presenting an isolated nodule histopathologically mimicking a primary cutaneous CD30+ T-cell lymphoproliferative disorder.