Clinical Presentation, Pathological Spectrum, and Outcomes of Alcoholic Cirrhosis-Related Immunoglobulin A Nephropathy.

Introduction: Immunoglobulin A nephropathy (IgAN) associated with cirrhosis is frequent but often overlooked because it is largely considered silent. Until now, little has been known about their presentation and outcomes. Methods: We conducted a retrospective multicenter study on patients with kidney biopsy-proven cirrhosis-related IgAN (cirrhosis-IgAN), diagnosed between 2009 and 2022. We mixed them up with 83 primary IgAN (pIgAN) diagnosed during the same period, using a partitioning clustering approach, to determine common clinicopathological profiles. Results: All the 46 patients with cirrhosis-IgAN had an excessive alcoholic consumption. Clinical presentation was severe with acute kidney injury (AKI) in 79%; alternative causes of AKI was found in 62% of cases. Three clinicopathological clusters were identified as follows: the first one represented chronic involvement, the second one could be assimilated to mild disease, and the third one corresponded to a membranoproliferative glomerulonephritis (MPGN) pattern and was associated with heavy proteinuria and intrinsic AKI (without alternative causes). Whereas the first 2 clusters were equally distributed between pIgAN and cirrhosis-IgAN, the third was more frequent in patients with cirrhosis. The cumulative mortality rate in cirrhosis-IgAN was 26% and 46% at 1-year and 3-years, respectively. Steroid exposure and moderate or severe AKI were associated with higher mortality and steroid exposure was associated with the occurrence of severe infection. Conclusion: Our results suggest that high AKI incidence is related to extrinsic causes in most cases but can also be driven by IgA-dominant MPGN in a subset of patients. Steroid use was associated with infectious disease and mortality. Further studies are needed to clarify the role of immunosuppressive treatment in cirrhosis-IgAN patients.

Non-myeloma light chain cast nephropathy: a multicenter retrospective study on clinicopathological characteristics.

Not available.

Artificial intelligence to improve cytology performance in urothelial carcinoma diagnosis: results from validation phase of the French, multicenter, prospective VISIOCYT1 trial.

PURPOSE: Cytology and cystoscopy, the current gold standard for diagnosing urothelial carcinomas, have limits: cytology has high interobserver variability with moderate or not optimal sensitivity (particularly for low-grade tumors); while cystoscopy is expensive, invasive, and operator dependent. The VISIOCYT1 study assessed the benefit of VisioCyt® for diagnosing urothelial carcinoma. METHODS: VISIOCYT1 was a French prospective clinical trial conducted in 14 centers. The trial enrolled adults undergoing endoscopy for suspected bladder cancer or to explore the lower urinary tract. Participants were allocated either Group 1: with bladder cancer, i.e., with positive cystoscopy or with negative cystoscopy but positive cytology, or Group 2: without bladder cancer. Before cystoscopy and histopathology, slides were prepared for cytology and the VisioCyt® test from urine samples. The diagnostic performance of VisioCyt® was assessed using sensitivity (primary objective, 70% lower-bound threshold) and specificity (75% lower-bound threshold). Sensitivity was also assessed by tumor grade and T-staging. VisioCyt® and cytology performance were evaluated relative to the histopathological assessments. RESULTS: Between October 2017 and December 2019, 391 participants (170 in Group 1 and 149 in Group 2) were enrolled. VisioCyt®'s sensitivity was 80.9% (95% CI 73.9-86.4%) and specificity was 61.8% (95% CI 53.4-69.5%). In high-grade tumors, the sensitivity was 93.7% (95% CI 86.0-97.3%) and in low-grade tumors 66.7% (95% CI 55.2-76.5%). Sensitivity by T-staging, compared to the overall sensitivity, was higher in high-grade tumors and lower in low-grade tumors. CONCLUSION: VisioCyt® is a promising diagnostic tool for urothelial cancers with improved sensitivities for high-grade tumors and notably for low-grade tumors.

Hypomagnesemia, Hypocalcemia, and Tubulointerstitial Nephropathy Caused by Claudin-16 Autoantibodies.

BACKGROUND: Chronic hypomagnesemia is commonly due to diarrhea, alcoholism, and drugs. More rarely, it is caused by genetic defects in the effectors of renal magnesium reabsorption. METHODS: In an adult patient with acquired severe hypomagnesemia, hypocalcemia, tubulointerstitial nephropathy, and rapidly progressing kidney injury, similarities between the patient's presentation and features of genetic disorders of renal magnesium transport prompted us to investigate whether the patient had an acquired autoimmune cause of renal magnesium wasting. To determine if the patient's condition might be explained by autoantibodies directed against claudin-16 or claudin-19, transmembrane paracellular proteins involved in renal magnesium absorption, we conducted experiments with claudin knockout mice and transfected mouse kidney cells expressing human claudin-16 or claudin-19. We also examined effects on renal magnesium handling in rats given intravenous injections of IgG purified from sera from the patient or controls. RESULTS: Experiments with the knockout mice and in vitro transfected cells demonstrated that hypomagnesemia in the patient was causally linked to autoantibodies directed against claudin-16, which controls paracellular magnesium reabsorption in the thick ascending limb of Henle's loop. Intravenous injection of IgG purified from the patient's serum induced a marked urinary waste of magnesium in rats. Immunosuppressive treatment combining plasma exchange and rituximab was associated with improvement in the patient's GFR, but hypomagnesemia persisted. The patient was subsequently diagnosed with a renal carcinoma that expressed a high level of claudin-16 mRNA. CONCLUSIONS: Pathogenic claudin-16 autoantibodies represent a novel autoimmune cause of specific renal tubular transport disturbances and tubulointerstitial nephropathy. Screening for autoantibodies targeting claudin-16, and potentially other magnesium transporters or channels in the kidney, may be warranted in patients with acquired unexplained hypomagnesemia.

Immune alveolitis in interstitial lung disease: an attractive cytological profile in immunocompromised patients.

BACKGROUND: Bronchoalveolar lavage (BAL) is a major diagnostic tool in interstitial lung disease (ILD). Its use remains largely quantitative, usually focused on cell differential ratio. However, cellular morphological features provide additional valuable information. The significance of the "immune alveolitis" cytological profile, characterized by lymphocytic alveolitis with activated lymphocytes and macrophages in epithelioid transformation or foamy macrophages desquamating in cohesive clusters with lymphocytes, remains unknown in ILD. Our objective was to describe patients' characteristics and diagnoses associated with an immune alveolitis profile in undiagnosed ILD. METHODS: We performed a monocentric retrospective observational study. Eligible patients were adults undergoing diagnostic exploration for ILD and whose BAL fluid displayed an immune alveolitis profile. For each patient, we collected clinical, radiological and biological findings as well as the final etiology of ILD. RESULTS: Between January 2012 and December 2018, 249 patients were included. Mean age was 57 ± 16 years, 140 patients (56%) were men, and 65% of patients were immunocompromised. The main etiological diagnosis was Pneumocystis pneumonia (PCP) (24%), followed by drug-induced lung disease (DILD) (20%), viral pneumonia (14%) and hypersensitivity pneumonitis (HP) (10%). All PCP were diagnosed in immunocompromised patients while HP was found in only 8% of this subgroup. DILD and viral pneumonia were also commonly diagnosed in immunocompromised patients (94% and 80%, respectively). CONCLUSION: Our study highlights the additional value of BAL qualitative description in ILD. We suggest incorporating the immune alveolitis profile for the diagnosis and management of ILD, especially in immunocompromised patients, since it guides towards specific diagnoses.

Complement Activation and Thrombotic Microangiopathy Associated With Monoclonal Gammopathy: A National French Case Series.

RATIONALE & OBJECTIVE: Hemolytic uremic syndrome (HUS), a thrombotic microangiopathy (TMA) with kidney involvement, is a rare condition in patients with monoclonal gammopathy. In the absence of known causes of TMA, the role of complement activation in endothelial injury in patients with monoclonal gammopathy remains unknown and was the focus of this investigation. STUDY DESIGN: Case series. SETTING & PARTICIPANTS: We studied the 24 patients in the French national registry of HUS between 2000 and 2020 who had monoclonal gammopathy without other causes of secondary TMA. We provide the clinical histories and complement studies of these patients. FINDINGS: Monoclonal gammopathy-associated TMA with kidney involvement is estimated to be 10 times less frequent than adult atypical HUS (aHUS) in the French national registry. It is characterized by severe clinical features, with 17 of 24 patients requiring dialysis at disease onset, and with median renal survival of only 20 months. TMA-mediated extrarenal manifestations, particularly cutaneous and neurological involvement, were common and associated with poor overall prognosis. Complement studies identified low C3, normal C4, and high soluble C5b-9 levels in 33%, 100%, and 77% of tested patients, respectively, indicating a contribution of the alternative and terminal complement pathways in the pathophysiology of the disease. Genetic abnormalities in complement genes known to be associated with aHUS were found in only 3 of 17 (17%) who were tested. LIMITATIONS: Retrospective study without comparison group; limited number of patients, limited available blood samples. CONCLUSIONS: Within the spectrum of TMA, TMA associated with monoclonal gammopathy represents a distinct subset. Our findings suggest that HUS associated with monoclonal immunoglobulin is a complement-mediated disease akin to aHUS.

Non-permissive human conventional CD1c+ dendritic cells enable trans-infection of human primary renal tubular epithelial cells and protect BK polyomavirus from neutralization.

The BK polyomavirus (BKPyV) is a ubiquitous human virus that persists in the renourinary epithelium. Immunosuppression can lead to BKPyV reactivation in the first year post-transplantation in kidney transplant recipients (KTRs) and hematopoietic stem cell transplant recipients. In KTRs, persistent DNAemia has been correlated to the occurrence of polyomavirus-associated nephropathy (PVAN) that can lead to graft loss if not properly controlled. Based on recent observations that conventional dendritic cells (cDCs) specifically infiltrate PVAN lesions, we hypothesized that those cells could play a role in BKPyV infection. We first demonstrated that monocyte-derived dendritic cells (MDDCs), an in vitro model for mDCs, captured BKPyV particles through an unconventional GRAF-1 endocytic pathway. Neither BKPyV particles nor BKPyV-infected cells were shown to activate MDDCs. Endocytosed virions were efficiently transmitted to permissive cells and protected from the antibody-mediated neutralization. Finally, we demonstrated that freshly isolated CD1c+ mDCs from the blood and kidney parenchyma behaved similarly to MDDCs thus extending our results to cells of clinical relevance. This study sheds light on a potential unprecedented CD1c+ mDC involvement in the BKPyV infection as a promoter of viral spreading.

Reoxygenation during radiotherapy in intermediate-risk prostate cancer.

Hypoxia is a major risk factor of prostate cancer radioresistance. We evaluated hypoxia non-invasively, using 18F-Misonidazole PET/CT prior to radiotherapy and after a dose of 20 Gy in intermediate-risk prostate cancer patients. Decreased hypoxic volumes were observed in all patients, suggesting that radiotherapy induces early prostate tumor reoxygenation.

Evaluation of tumor hypoxia prior to radiotherapy in intermediate-risk prostate cancer using 18F-fluoromisonidazole PET/CT: a pilot study.

PURPOSE: Hypoxia is a major factor in prostate cancer aggressiveness and radioresistance. Predicting which patients might be bad candidates for radiotherapy may help better personalize treatment decisions in intermediate-risk prostate cancer patients. We assessed spatial distribution of 18F-Misonidazole (FMISO) PET/CT uptake in the prostate prior to radiotherapy treatment. MATERIALS AND METHODS: Intermediate-risk prostate cancer patients about to receive high-dose (>74 Gy) radiotherapy to the prostate without hormonal treatment were prospectively recruited between 9/2012 and 10/2014. Prior to radiotherapy, all patients underwent a FMISO PET/CT as well as a MRI and 18F-choline-PET. 18F-choline and FMISO-positive volumes were semi-automatically determined using the fuzzy locally adaptive Bayesian (FLAB) method. In FMISO-positive patients, a dynamic analysis of early tumor uptake was performed. Group differences were assessed using the Wilcoxon signed rank test. Parameters were correlated using Spearman rank correlation. RESULTS: Of 27 patients (median age 76) recruited to the study, 7 and 9 patients were considered positive at 2.5h and 3.5h FMISO PET/CT respectively. Median SUVmax and SUVmax tumor to muscle (T/M) ratio were respectively 3.4 and 3.6 at 2.5h, and 3.2 and 4.4 at 3.5h. The median FMISO-positive volume was 1.1 ml. CONCLUSIONS: This is the first study regarding hypoxia imaging using FMISO in prostate cancer showing that a small FMISO-positive volume was detected in one third of intermediate-risk prostate cancer patients.

Gestational choriocarcinoma associated with a germline TP53 mutation.

Choriocarcinoma is a highly malignant neoplasm resulting from the malignant transformation of proliferating trophoblastic cells and the molecular mechanisms leading to this transformation remain to be characterized. We report here the first case of a female germline TP53 mutation carrier who developed, as a first tumour, a lung choriocarcinoma, 6 months after a normal delivery. Molecular analyses established the gestational origin of the choriocarcinoma and showed, within the tumour, the presence of the germline mutant TP53 allele and loss of the wild-type allele. Resistance to methotrexate chemotherapy led to perform a surgical resection of the tumour. In agreement with the permissive role of TP53 mutations to oncogenic events, this report strongly suggests that TP53 mutations may promote malignant transformation of proliferating trophoblastic cells. Therefore, female TP53 mutation carriers may have an increased risk of developing gestational choriocarcinoma and might benefit from ß-hCG level monitoring after pregnancy.