Decoding the molecular heterogeneity of pediatric monomorphic post-solid organ transplant lymphoproliferative disorders.

Posttransplant lymphoproliferative disorders (PTLDs) represent a broad spectrum of lymphoid proliferations, frequently associated with Epstein-Barr virus (EBV) infection. The molecular profile of pediatric monomorphic PTLDs (mPTLDs) has not been elucidated, and it is unknown whether they display similar genetic features as their counterpart in adult and immunocompetent (IMC) pediatric patients. In this study, we investigated 31 cases of pediatric mPTLD after solid organ transplantation, including 24 diffuse large B-cell lymphomas (DLBCLs), mostly classified as activated B cell, and 7 cases of Burkitt lymphoma (BL), 93% of which were EBV positive. We performed an integrated molecular approach, including fluorescence in situ hybridization, targeted gene sequencing, and copy number (CN) arrays. Overall, PTLD-BL carried mutations in MYC, ID3, DDX3X, ARID1A, or CCND3 resembling IMC-BL, higher mutational burden than PTLD-DLBCL, and lesser CN alterations than IMC-BL. PTLD-DLBCL showed a very heterogeneous genomic profile with fewer mutations and CN alterations than IMC-DLBCL. Epigenetic modifiers and genes of the Notch pathway were the most recurrently mutated in PTLD-DLBCL (both 28%). Mutations in cell cycle and Notch pathways correlated with a worse outcome. All 7 patients with PTLD-BL were alive after treatment with pediatric B-cell non-Hodgkin lymphoma protocols, whereas 54% of patients with DLBCL were cured with immunosuppression reduction, rituximab, and/or low-dose chemotherapy. These findings highlight the low complexity of pediatric PTLD-DLBCL, their good response to low-intensity treatment, and the shared pathogenesis between PTLD-BL and EBV-positive IMC-BL. We also suggest new potential parameters that could help in the diagnosis and the design of better therapeutic strategies for these patients.

Cystic phenotype and chronic kidney disease in autosomal dominant Alport syndrome.

BACKGROUND: Autosomal dominant Alport Syndrome (ADAS), also known as thin basement membrane disease (TBMD), is caused by pathogenic variants in the COL4A3 and COL4A4 genes. A cystic phenotype has been described in some patients with TBMD, but no genetic studies have been performed. We conducted a genetic and radiologic investigation in a cohort of ADAS patients to analyze the prevalence of multicystic kidney disease (MKD) and its association with chronic kidney disease (CKD). METHODS: This was a retrospective single-center cohort study. Thirty-one patients showing pathogenic or likely pathogenic variants in COL4A3 or COL4A4 from a cohort of 79 patients with persistent microscopic hematuria were included. Mean follow-up was 9.4 ± 9.6 years. The primary objective of the study was to determine the prevalence of MKD in the cohort of ADAS patients. Secondary objectives were to determine risk factors associated with an estimated glomerular filtration rate (eGFR) <45 mL/min/1.73 m2 at the time of genetic and radiologic evaluation and to investigate the coexistence of other genetic abnormalities associated with familial hematuria and cystic kidney disease. RESULTS: MKD was found in 16 patients (52%). Mean number of cysts per kidney was 12.7 ± 5.5. No genetic abnormalities were found in a panel of 101 other genes related to familial hematuria, focal segmental glomerulosclerosis and cystic kidney disease. A greater number of patients with MKD had an eGFR <45 mL/min/1.73 m2 (63% vs 7%, P = .006) and more advanced CKD than patients without MKD. The annual rate of eGFR decline was greater in patients with MKD: -1.8 vs 0.06 mL/min/1.73 m2/year (P = .009). By multivariable linear regression analysis, the main determinants of eGFR change per year were time-averaged proteinuria (P = .002) and MKD (P = .02). CONCLUSION: MKD is commonly found in ADAS and is associated with a worse kidney outcome. No pathogenic variants were found in genes other than COL4A3/COL4A4.

Intraparenchymal low-grade B-cell lymphomas of the central nervous system: Clinicopathologic and molecular analysis of three cases and a review of the literature.

Primary central nervous system (CNS) lymphomas represent 1 % of all non-Hodgkin lymphomas, with diffuse large B-cell lymphomas as the prevailing subtype. Low-grade B-cell lymphomas are exceptional with only 24 marginal zone B-cell lymphomas (EMZL) and 1 follicular lymphoma (FL) previously reported so far. While their molecular profiles are studied elsewhere, data on primary intraparenchymal CNS cases remain limited. The objective of the present study is to contribute new cases of primary intraprenchymal low-grade B-cell lymphomas in the CNS and characterize their mutational profile. We conducted a comprehensive review of cases and a literature review to identify similar instances. Clinical, imaging, histological, immunohistochemical, and molecular characteristics were analyzed. Diagnoses were established according to established criteria. We present three novel cases of intraparenchymal CNS low-grade B-cell lymphomas. One case of intraparenchymal EMZL exhibited plasmacytic differentiation, while another lacked a plasma cell component. The third case was diagnosed as FL. The L265P mutation of MYD88 was absent in all cases. Next generation sequencing revealed pathogenic mutations in SPEN (Glu1970ValfsTer64) and ARID1A (Pro1355LeufsTer118) genes in one EMZL case. In conclusion, intraparenchymal CNS low-grade B-cell lymphomas are rare, with few reported cases. Our findings expand knowledge on their clinical and molecular features. We present the first molecular profile of primary CNS intraparenchymal EMZL, underscoring the need for further research to understand their biology and optimize treatment strategies.

Renal vasculitis presenting with acute kidney injury.

Renal failure secondary to ANCA-associated vasculitis represents a clinical and therapeutic challenge. In this study, we aimed to assess the treatment response rates and long-term outcomes of vasculitis patients presenting with renal failure. This retrospective study included 151 patients with renal vasculitis from three hospitals who underwent a renal biopsy between 1997 and 2014. Patients with renal failure which required dialysis at the onset were compared to those presenting with more preserved renal function. The primary end point was treatment response and patient surivival. Patients with severe renal involvement had a lower response to treatment compared to those having preserved renal function (26.6 versus 93.4%; p < 0.001). Dialysis-dependent patients who received plasmapheresis in addition to immune suppressants associated a higher rate of renal recovery (41.6 versus 12.5%; p = 0.05). A higher incidence of severe infections was observed among patients with severe renal involvement (38.4 versus 18.1%, p = 0.01). The mortality rate was significantly higher among vasculitis patients presenting with renal failure (53.8 versus 22.2%, p = 0.001). Global survival at 1 and 5 years was 60 and 47% in patients requiring dialysis compared with 90 and 80% among those with more preserved renal function (p < 0.001). After multivariate adjustment, the need for dialysis remained as an independent predictor of death (HR 2.5; 95% CI 1.1-5.7; p = 0.03). The presence of severe renal dysfunction represents an independent risk factor for patient survival in renal vasculitis. Patients requiring dialysis associate a lower response rate to immunosuppressive therapy and a higher incidence of severe infections.

Antineutrophil cytoplasmic antibody negative pauci-immune extracapillary glomerulonephritis.

AIM: Pauci-immune extracapillary glomerulonephritis (PEGN) is one of the most common causes of rapidly progressive glomerulonephritis and is usually associated with circulating anti-neutrophil cytoplasmic antibodies (ANCAs). However, a significant number of individuals with PEGN test negative for ANCA and this study aimed to analyze the characteristics of this subgroup of patients. METHODS: Patients from two centres who were diagnosed with PEGN between 1997 and 2014 were studied retrospectively. Clinicopathological characteristics and renal outcome were compared between patients presenting with pauci-immune necrotizing extracapillary glomerulonephritis associated or not with the presence of circulating ANCA. RESULTS: Among the 114 patients with PEGN, 29 (25.4%) were ANCA negative. Compared with the 85 ANCA-positive patients, ANCA-negative patients were younger at the onset (54.8 ± 17.2 vs. 62 ± 14.0 years; P < 0.05). The median level of urinary protein excretion was significantly higher among ANCA-negative patients (3.1 vs. 1 g/24 h; P < 0.001), whereas no differences were found in renal function and need for dialysis between ANCA-negative and positive groups. Extrarenal involvement was present independently of ANCA status. Histological analysis showed that ANCA-negative patients were more likely to have mesangial proliferation (P < 0.05). Renal and global survival were similar between ANCA-negative and positive patients, and treatment response and relapse rates were comparable in both groups. CONCLUSIONS: ANCA-negative pauci-immune extracapillary glomerulonephritis is not a rare condition and is part of a systemic vasculitis disease. Although ANCA-negative patients have renal and histological characteristics that differ from ANCA-positive patients, renal survival and treatment response in PEGN are independent of ANCA status.

Impact on prognosis of the regional distribution of MGMT methylation with respect to the CpG island methylator phenotype and age in glioma patients.

Clinical and molecular prognostic factors in gliomas include age, IDH mutation, the glioma CpG island methylator phenotype (G-CIMP+) and promoter methylation of the O(6)-methylguanine DNA-methyltransferase (MGMT) gene. Among these markers, a predictive value was reported in glioblastomas (GBM) for MGMT promoter methylation, in particular in elderly GBM patients. In this study, methylation data from 46 glioma samples with the Illumina 450K platform were obtained and extended using external data to include a total of 247 glioma samples. Methylation analysis of the whole MGMT gene with this platform revealed two strongly survival-associated CpG regions within the promoter and the gene body, which were confirmed in a reported dataset of high grade-gliomas. Methylation at the promoter (CpG 25, cg12981137 and the prognostic model MGMT-STP27) and at the gene body CpG 165 (cg07933035), were significantly associated with better overall survival, and strongly correlated with G-CIMP+ status. In this series, the prognostic value of MGMT methylation at the promoter was not observed in G-CIMP- cases, although around 50 % of them were MGMT-methylated. These results were also obtained in an homogeneously-treated series of chemoradiated G-CIMP- GBMs analyzed by MSP and qMSP, and confirmed in a reported pyrosequencing-analyzed series of gliomas. Interestingly, in contrast to the MGMT promoter, gene body methylation was of prognostic value in G-CIMP-patients older than 65 years. Our study highlights the relevance of the prognostic value of the different regions of methylation throughout the MGMT gene that could be affected by specific G-CIMP profiles and age groups.

Tubular biomarkers and histology in lupus nephritis.

INTRODUCTION: The relevance of tubulo-interstitial involvement for kidney prognosis has recently been emphasized, but validated biomarkers for predicting histology are still lacking. The aim of our study was to evaluate different serum and urinary markers of tubular damage in patients with lupus nephritis (LN) and to correlate them with kidney histopathology. METHODS: A single-center retrospective study was conducted from January 2016 to December 2021. Serum and urine samples were collected on the same day of kidney biopsy and correlated with histologic data from a cohort of 15 LN patients. We analyzed the following urinary markers, adjusted for urine creatinine: beta 2-microglobulin, alpha 1-microglobulin, NGAL, uKIM-1, MCP-1, uDKK-3, and uUMOD. The serum markers sKIM-1 and sUMOD were also analyzed. RESULTS: A positive and strong correlation was observed between the degree of interstitial fibrosis (rho = 0.785, p = .001) and tubular atrophy (rho = 0.781, p = .001) and the levels of uDKK3. uUMOD also showed an inverse and moderate correlation with interstitial fibrosis (rho = -0.562, p = .037) and tubular atrophy (rho = -0.694, p = .006). Patients with >10% cortical interstitial inflammation had higher levels of uKIM-1 [4.9 (3.9, 5.5) vs. 0.8 (0.6, 1.5) mcg/mg, p = .001], MCP-1 [3.8 (2. 3, 4.2) vs. 0.7 (0.3, 1.2) mcg/mg, p = .001], sKIM-1 [9.2 (5.9, 32.7) vs. 1.4 (0, 3.5) pg/mL, p = .001], and lower sUMOD [8.7 (0, 39.7) vs. 46.1 (35.7, 53) ng/mL, p = .028]. CONCLUSION: The use of specific urinary and serum biomarkers of tubular dysfunction or injury may help to predict certain histologic parameters in LN patients.

Tubular biomarkers in proteinuric kidney disease: histology correlation and kidney prognosis of tubular biomarkers.

Background: Proteinuria is not only a biomarker of chronic kidney disease (CKD) but also a driver of CKD progression. The aim of this study was to evaluate serum and urinary tubular biomarkers in patients with biopsied proteinuric kidney disease and to correlate them with histology and kidney outcomes. Methods: A single-center retrospective study was conducted on a cohort of 156 patients from January 2016 to December 2021. The following urinary and serum biomarkers were analyzed on the day of kidney biopsy: beta 2 microglobulin (ß2-mcg), alpha 1 microglobulin (α1-mcg), neutrophil gelatinase-associated lipocalin (NGAL), urinary kidney injury molecule-1 (uKIM-1), monocyte chemoattractant protein-1 (MCP-1), urinary Dickkopf-3 (uDKK3), uromodulin (urinary uUMOD), serum kidney injury molecule-1 (sKIM-1) and serum uromodulin (sUMOD). A composite outcome of kidney progression or death was recorded during a median follow-up period of 26 months. Results: Multivariate regression analysis identified sUMOD (ß-0.357, P < .001) and uDKK3 (ß 0.483, P < .001) as independent predictors of interstitial fibrosis, adjusted for age, estimated glomerular filtration rate (eGFR) and log proteinuria. Elevated levels of MCP-1 [odds ratio 15.61, 95% confidence interval (CI) 3.52-69.20] were associated with a higher risk of cortical interstitial inflammation >10% adjusted for eGFR, log proteinuria and microhematuria. Upper tertiles of uDKK3 were associated with greater eGFR decline during follow-up. Although not a predictor of the composite outcome, doubling of uDKK3 was a predictor of kidney events (hazard ratio 2.26, 95% CI 1.04-4.94) after adjustment for interstitial fibrosis, eGFR and proteinuria. Conclusions: Tubular markers may have prognostic value in proteinuric kidney disease, correlating with specific histologic parameters and identifying cases at higher risk of CKD progression.

Cell-Free DNA Dynamic Concentration and Other Variables Are Predictors of Early Progression after Chimeric Antigen Receptor T Cell Therapy in Patients with Diffuse Large B Cell Lymphoma.

We propose a novel biomarker that can identify patients at high risk of early progression after chimeric antigen receptor (CAR) T cell therapy. Calculation of cell-free DNA (cfDNA) with a pre-apheresis (PA) and pre-lymphodepletion (PL) sample allows monitoring of tumor dynamics (∆cfDNA). In the present study, ∆cfDNA and other biomarkers and clinical variables were evaluated in 58 patients with relapsed/refractory diffuse large B cell lymphoma (DLBCL). ∆cfDNA (>11 ng/mL plasma; P =.003), C-reactive protein (CRP) PL (>1.06 mg/dL; P = .004), lactate dehydrogenase (LDH) PL (>304; P = .006), disease status PL (progressive disease; P = .035) and sex (male; P = .016) were highly correlated with 1 month progression. After adjusting for ∆cfDNA, CRP PL, and LDH PL, disease status PL, and sex, ∆cfDNA remained associated with 1-month progression after CAR T cell infusion.

Atherosclerotic plaque development in mice is enhanced by myeloid ZEB1 downregulation.

Accumulation of lipid-laden macrophages within the arterial neointima is a critical step in atherosclerotic plaque formation. Here, we show that reduced levels of the cellular plasticity factor ZEB1 in macrophages increase atherosclerotic plaque formation and the chance of cardiovascular events. Compared to control counterparts (Zeb1WT/ApoeKO), male mice with Zeb1 ablation in their myeloid cells (Zeb1∆M/ApoeKO) have larger atherosclerotic plaques and higher lipid accumulation in their macrophages due to delayed lipid traffic and deficient cholesterol efflux. Zeb1∆M/ApoeKO mice display more pronounced systemic metabolic alterations than Zeb1WT/ApoeKO mice, with higher serum levels of low-density lipoproteins and inflammatory cytokines and larger ectopic fat deposits. Higher lipid accumulation in Zeb1∆M macrophages is reverted by the exogenous expression of Zeb1 through macrophage-targeted nanoparticles. In vivo administration of these nanoparticles reduces atherosclerotic plaque formation in Zeb1∆M/ApoeKO mice. Finally, low ZEB1 expression in human endarterectomies is associated with plaque rupture and cardiovascular events. These results set ZEB1 in macrophages as a potential target in the treatment of atherosclerosis.

Hemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS) following treatment with tisagenlecleucel.

Chimeric antigen receptor (CAR) T cell-related HLH/MAS is an unusual manifestation of severe cytokine release syndrome (CRS) with poor prognosis and a challenging diagnosis. The establishment of specific diagnosis criteria is essential, and the combination of several techniques for CAR T-cell follow-up, allows a more precise management of this complication.

Long-term validation of the renal risk score for vasculitis in a Southern European population.

BACKGROUND: Recently, renal risk score on the basis of three clinicopathologic features to predict end-stage renal disease (ESRD) in antineutrophil cytoplasmic antibody (ANCA)-associated renal vasculitis has been proposed. The aim of this multi-centre study was to validate this renal risk score in a large cohort of southern European patients. METHODS: Data were retrospectively collected from the time of diagnosis by systematic review of medical records from 147 patients with renal vasculitis recruited from three Spanish centres. The renal risk score was calculated in every patient, and renal and global outcomes were analysed according to the risk group assessment. RESULTS: ANCA serology was positive in 76.2% of patients: 64.6% showed activity against myeloperoxidase (MPO) and 12.2% against proteinase 3 (PR3). The median (interquartile range) follow-up period was 41 months (9.6-104). Forty-eight patients (32.7%) reached ESRD. Patients were classified into the three groups according to the risk of progression to ESRD: 21.8% of patients were classified into low risk, 52.4% were classified into moderate risk and the remaining 25.9% were classified into high risk. The cumulative proportion of renal survival at 2, 5 and 10 years was 100, 100 and 82% in the low-risk group, 79, 77 and 77% in the medium-risk group and 63, 53 and 40% in the high-risk group (P < 0.001). In regression analysis, the risk score was a good predictor for the development of the ESRD among ANCA positive [hazard ratio (HR) = 2.7, 95% confidence interval (CI) 1.4-4.9; P < 0.001] and ANCA negative (HR = 2.7, 95% CI 1.04-7.1, P = 0.04) patients. CONCLUSIONS: The renal risk score constitutes an accurate tool to predict renal outcome among patients with renal vasculitis. This study contributes to validate the risk scoring system in a MPO-predominant population, but also among ANCA-negative vasculitis patients.

Urinary soluble CD163 as a biomarker of disease activity and relapse in antineutrophil cytoplasm antibody-associated glomerulonephritis.

BACKGROUND: Antineutrophil cytoplasm antibody (ANCA)-associated vasculitis is a chronic relapsing and remitting autoimmune disease. Urinary soluble CD163 (usCD163) has been proposed as a biomarker of active renal vasculitis. We aimed to assess the potential usefulness of usCD163 for diagnosing renal relapse in patients with ANCA-associated glomerulonephritis. METHODS: One hundred and fifty-six samples from 47 patients with ANCA-associated glomerulonephritis belonging to two different cohorts (incident and prevalent) and 20 healthy controls were studied. Patients from the incident cohort were prospectively followed up, and usCD163 concentrations were measured every 3 months. Renal relapses were identified and changes in usCD163 concentrations were analysed. RESULTS: Normalized usCD163 concentrations were elevated at disease onset in all patients with active renal vasculitis, with a median concentration of 601 ng/mmol (interquartile range 221-1404 ng/mmol). On the other hand, usCD163 concentrations were undetectable among control patients with renal vasculitis in remission. Except for non-responders, usCD163 concentrations progressively decreased in all patients after treatment. In the presence of vasculitis relapse, there was a consistent increase in usCD163 concentrations, compared with previous values. The area under the receiver-operating characteristic curve of absolute and relative changes in usCD163 concentrations to identify relapse of ANCA-associated glomerulonephritis was 0.96 [95% confidence interval (CI) 0.91-1.00; P = 0.001] and 0.95 (95% CI 0.90-1.00; P = 0.001), respectively. Sensitivity and specificity for a relative increase of 20%, or an absolute increase of 20 ng/mmol, in usCD163 concentrations were 100% for both, and 89.3% and 87.5%, respectively. Urinary sCD163 concentrations significantly correlated with Birmingham Vasculitis Activity Score scores at Month 6 (r = 0.737; P = 0.006) and Month 12 (r = 0.804; P = 0.005). CONCLUSIONS: usCD163 represents an accurate biomarker for the detection of active renal vasculitis and relapse. Its close association with disease activity provides additional information for monitoring treatment response.

Incorporation of next-generation sequencing in clinical practice using solid and liquid biopsy for patients with non-Hodgkin's lymphoma.

Although next-generation sequencing (NGS) data on lymphomas require further validation before being implemented in daily practice, the clinical application of NGS can be considered right around the corner. The aim of our study was to validate an NGS lymphoid panel for tissue and liquid biopsy with the most common types of non-Hodgkin's lymphoma [follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL)]. In this series, 372 somatic alterations were detected in 93.6% (44/47) of the patients through tissue biopsy. In FL, we identified 93 somatic alterations, with a median of 7.4 mutations per sample. In DLBCL, we detected 279 somatic variants with a median of 8.6 mutations (range 0-35). In 92% (24/26) of the cases, we were able to detect some variant in the circulating tumor DNA. We detected a total of 386 variants; 63.7% were detected in both types of samples, 13.2% were detected only in the circulating tumor DNA, and 23% were detected only in the tissue biopsy. We found a correlation between the number of circulating tumor DNA mutations, advanced stage, and bulky disease. The genetic alterations detected in this panel were consistent with those previously described at diagnosis. The liquid biopsy sample is therefore a complementary tool that can provide new genetic information, even in cases where a solid biopsy cannot be performed or an insufficient sample was obtained. In summary, we describe and analyze in this study the findings and difficulties encountered when incorporating liquid biopsy into clinical practice in non-Hodgkin's lymphoma at diagnosis.

Membranoproliferative Glomerulonephritis and Mixed Cryoglobulinemia as a Form of Presentation of Visceral Leishmaniasis.

BACKGROUND Visceral leishmaniasis (VL) is an endemic systemic disease in the Mediterranean countries, including Spain. This vector-borne infection can present with several clinical presentations, from asymptomatic to severe forms. Renal impairment is frequently described in VL but is usually mild and related to interstitial nephritis, being that glomerular involvement is rarely found. CASE REPORT We describe a case of a 69-year-old Spanish male presenting with subacute renal failure due to membranoproliferative glomerulonephritis and mixed cryoglobulinemia accompanied by other autoimmune features (hypocomplementemia, antinuclear and antiDNA antibodies). No hepatosplenomegaly was found with abdominal ultrasound. Hepatotropic viruses and human immunodeficiency virus serological markers were negatives. We initially suspect the presence of an autoimmune disease and the patient was treated with steroids without improvement. After an extensive study including renal and bone marrow biopsy, a correct diagnosis of visceral leishmaniasis was made, and treatment with liposomal amphotericin B was initiated, achieving renal function recovery and normalization of immunological manifestations. CONCLUSIONS Renal involvement can be an important feature of VL and it might be associated with increased morbidity and mortality. The association between mixed cryoglobulinemia and renal involvement in VL have rarely been described. VL is frequently associated with diverse autoimmune manifestations and it can be initially misdiagnosed, which could lead to fatal consequences. The role of the immune system in the formation of cryoglobulins are discussed. In our case, an autoimmune disease was initially suspected, and starting treatment with steroids pulses was initiated. However, the presence of mixed cryoglobulinemia in this patient who was hepatitis C serological marker negative and who had poor renal function recovery after immunosuppressive treatment made us suspect other pathologies. The presence of cryoglobulinemia with renal disease in endemic areas of Leishmania should make us exclude this infection before starting immunosuppressive treatment.

Papillary tumor of the pineal region: Case report and review of the literature.

Papillary tumor of the pineal region is a rare neuroepithelial tumor characterized by papillary architecture and epithelial cytology, immunopositivity for cytokeratin and ependymal differentiation. It is considered grade II-III by the World Health Organization and was first described by Jouvet in 2003. We present a 34-year-old male with headaches, blurred vision and normal examination. Radiological study showed a nodulocystic lesion in the pineal region compatible with pineocytoma. Surgery was performed using an infratentorial supracerebellar approach, finding a cystic tumor in the quadrigeminal cistern which was completely resected. Histopathology reported a papillary tumor of the pineal region. The patient made good progress without adjuvant therapy, and after 57 months of follow-up he remained asymptomatic and free of recurrence. A review of the literature was performed to collect all the cases published with gross total resection and no complementary treatment. In conclusion, there is still much to be learned about the pathogenesis, prognosis and management of this tumor.