Interferon regulatory factor 4 plays a pivotal role in the development of aGVHD-associated colitis.

Interferon regulatory factor 4 (IRF4) is a master transcription factor that regulates T helper cell (Th) differentiation. It interacts with the Basic leucine zipper transcription factor, ATF-like (BATF), depletion of which in CD4+ T cells abrogates acute graft-versus-host disease (aGVHD)-induced colitis. Here, we investigated the immune-regulatory role of Irf4 in a mouse model of MHC-mismatched bone marrow transplantation. We found that recipients of allogenic Irf4-/- CD4+ T cells developed less GVHD-related symptoms. Transcriptome analysis of re-isolated donor Irf4-/- CD4+ T helper (Th) cells, revealed gene expression profiles consistent with loss of effector T helper cell signatures and enrichment of a regulatory T cell (Treg) gene expression signature. In line with these findings, we observed a high expression of the transcription factor BTB and CNC homolog 2; (BACH2) in Irf4-/- T cells, which is associated with the formation of Treg cells and suppression of Th subset differentiation. We also found an association between BACH2 expression and Treg differentiation in patients with intestinal GVHD. Finally, our results indicate that IRF4 and BACH2 act as counterparts in Th cell polarization and immune homeostasis during GVHD. In conclusion, targeting the BACH2/IRF4-axis could help to develop novel therapeutic approaches against GVHD.

Entamoeba histolytica-associated proctitis and ileitis mimicking Crohn's disease-A case report.

We report about a proctitis and ileitis terminalis, leading to the misdiagnosis of Chron's disease, in a male patient who has sex with men. Molecular multiplex analysis identified Entamoeba histolytica as the underlying cause. We provide diagnostic images, clues and pitfalls for diagnosis of E. histolytica associated proctitis.

Round-Robin test for the histological diagnosis of acute colonic Graft-versus-Host disease validating established histological criteria and grading systems.

Histomorpholgy is one of the mainstays of acute Graft-versus-host disease (GvHD) diagnosis. However, concerns about reproducibility and the most appropriate grading system question its usefulness. Our aim was to assess histomorphological parameters and previously reported grading systems for GvHD regarding reproducibility and validity. Moreover, we propose that sum scores, derived by combining separately scored morphological parameters into a total score, might provide a simplified but equally effective means to grade GvHD. A total of 123 colon biopsies were assessed across four pathologists for intestinal GvHD using a Round-Robin test and results were correlated with clinical findings. Interobserver reproducibility was high for histological parameters that were evaluated as indicators of acute GvHD. Published grading systems were moderately reproducible (ICC 0.679-0.769) while simplified sum scores, in comparison, showed better interrater reliability (ICC 0.818-0.896). All grading systems and sum scores were associated with clinical signs of GvHD and in part with therapy response and survival. However, they were not able to stratify patients according to the clinical severity of GvHD. In a hot-spot analysis 1 crypt apoptotic body (CAB) in 10 crypts was a reasonable cut-off value for minimal diagnostic criteria of GvHD. In conclusion, histology can contribute to the diagnosis of GvHD and is reproducible. Published grading systems are able to reflect clinical findings as are simplified sum scores, which showed improved reproducibility and might be easier to handle as they are based on adding up histological parameters rather than transferring histological findings into a separate grading system. Sum scores will have to be further tested in a prospective setting.

Histological diagnosis of acute graft-versus-host disease in different sites of the upper gastrointestinal tract with correlation to endoscopic findings.

Graft-versus-host disease (GvHD) involving the intestine is a threat to patients after allogeneic hematopoietic stem cell transplantation (alloHSCT). We evaluated biopsies from different sites of the upper gastrointestinal tract (GIT) of 97 patients after alloHSCT. Forty-six patients with clinical symptoms consistent with upper GI GvHD revealed histological features of GvHD in the esophagus, stomach, and/or duodenum. Biopsies of the duodenum and esophagus were significantly more sensitive for signs of GvHD than those of the gastric antrum or corpus. The histological features of GvHD were significantly correlated with the endoscopic findings of ulcers, erosion, atrophy, and white plaques; however, the sensitivity and specificity of the latter were low. In univariate analysis, overall mortality was significantly associated with histological GvHD signs in all four sites. Nonrelapse mortality was associated with histologic GvHD features in the antrum only. Regarding GvHD diagnosis, biopsies of the upper gastrointestinal tract should include the duodenum and/or esophagus.

Prevalence of corneal findings and their interrelation with hematological findings in monoclonal gammopathy.

PURPOSE: To determine prevalence of paraproteinemic keratopathy (PPK) among patients with monoclonal gammopathy (MG). To evaluate interrelation between corneal and hematological parameters in patients with PPK. METHODS: Fifty-one patients with monoclonal gammopathy of undetermined significance (n = 19), smoldering multiple myeloma (n = 5) or multiple myeloma (n = 27) were prospectively included in this study. Best-corrected visual acuity, slit-lamp biomicroscopy, Scheimpflug tomography, in-vivo confocal laser scanning microscopy, optical coherence tomography and complete hematological workup were assessed. RESULTS: We identified n = 19 patients with bilateral corneal opacities compatible with PPK. PPK was newly diagnosed in 13 (29%) of 45 patients with a primary hematological diagnosis and in n = 6 patients without previous hematological diagnosis. The most common form was a discreet stromal flake-like PPK (n = 14 of 19). The median level of M-protein (p = 0.59), IgA (p = 0.53), IgG (p = 0.79) and IgM (p = 0.59) did not differ significantly between the patients with and without PPK. The median level of the FLC κ in serum of patients with kappa-restricted plasma cell dyscrasia was 209 mg/l in patients with PPK compared to 38.1 mg/l in patients without PPK (p = 0.18). Median level of FLC lambda in serum of patients with lambda-restricted plasma cell dyscrasia was lower in patients with PPK compared to patients without PPK (p = 0.02). CONCLUSION: The PPK was mostly discreet, but its prevalence (29%) was higher than expected. Median level of the monoclonal paraprotein was not significantly higher in patients with PPK compared to patients without PPK. Our results suggest a lack of correlation between morphology and severity of the ocular findings and severity of the monoclonal gammopathy. TRIAL REGISTRATION: German Clinical Trial Register: DRKS00023893.

Siltuximab-Related Favorable Clinical Outcome for a Patient Suffering from Idiopathic Multicentric Castleman Disease.

RationalCastleman disease is a rare lymphoproliferative disorder that can be subdivided into unicentric and multicentric forms, the latter of which causes a spectrum of serious medical conditions. Here, we present a case of idiopathic multicentric Castleman disease in the eighth decade of life. Patient Concerns. First hospitalized due to unexplained progressive anemia, the patient was readmitted to the hospital 18 months later with suspected lymphoma. Clinical examination revealed a progressive lymphadenopathy. Diagnoses. Histopathologic lymph node features, anemia, elevated CRP and IL6 levels, splenomegaly, and hypoalbuminemia indicated multicentric Castleman (MCD) disease. Interventions. The patient was treated intravenously with a dose of 11 mg/kg siltuximab every 3 weeks. Outcomes. Timely correct diagnosis through the stringent use of consensus diagnostic criteria and sufficient siltuximab therapy has considerably promoted favorable clinical outcomes in a patient suffering from MCD.

Veno-occlusive disease of the lung after allogeneic haematopoietic stem-cell transplantation: An autopsy study.

Pulmonary veno-occlusive disease (pVOD) is a potentially life-threatening sequela of allogeneic haematopoietic stem-cell transplantation (alloHSCT). We conducted a morphometric evaluation of autopsy lung tissue to determine the incidence of pVOD and its association with donor type, conditioning regime, hepatic sinusoidal obstruction syndrome (hSOS), survival time, and graft versus host disease (GvHD). The degree of occlusion of pulmonary veins in 78 autopsy cases after alloHSCT and 12 control cases was assigned to one of the following categories: none, minor thickening of the intima (up to 33% narrowing), moderate pVOD wherein about half of the lumen (34-66%) is occluded, or advanced pVOD with near total or total (67-100%) obliteration of the lumen. Minor thickening of the intima was found in all patients after alloHSCT (median: 66% of the vessels) and it was found to a lesser extent in the control cases (median: 12%). Moderate to advanced pVOD was seen in 95% of the cases, but only in a minority of the veins and venules (median: 6% of the veins and venules). PVOD was not significantly correlated with other histopathological findings within the lungs, including acute pneumonia, desquamative pneumonia, acute respiratory distress syndrome, organising and non-specific pneumonia, and bronchiolitis obliterans or acute lung disease. PVOD was significantly associated with a conditioning regimen including cyclophosphamide, fludarabine, or antithymocyte globulin and the duration of survival after alloHSCT. It was not associated with acute or chronic GvHD, other intestinal lung diseases, hSOS, or donor characteristics. PVOD was found in most patients after they underwent alloHSCT, although it mainly involved only a minority of the vessels. It was associated with the conditioning regime and the duration of survival after alloHSCT.

Evaluation of novel LCI CAD EYE system for real time detection of colon polyps.

BACKGROUND: Linked color imaging (LCI) has been shown to be effective in multiple randomized controlled trials for enhanced colorectal polyp detection. Recently, artificial intelligence (AI) with deep learning through convolutional neural networks has dramatically improved and is increasingly recognized as a promising new technique for enhancing colorectal polyp detection. AIM: This study aims to evaluate a newly developed computer-aided detection (CAD) system in combination with LCI for colorectal polyp detection. METHODS: First, a convolutional neural network was trained for colorectal polyp detection in combination with the LCI technique using a dataset of anonymized endoscopy videos. For validation, 240 polyps within fully recorded endoscopy videos in LCI mode, covering the entire spectrum of adenomatous histology, were used. Sensitivity (true-positive rate per lesion) and false-positive frames in a full procedure were assessed. RESULTS: The new CAD system used in LCI mode could process at least 60 frames per second, allowing for real-time video analysis. Sensitivity (true-positive rate per lesion) was 100%, with no lesion being missed. The calculated false-positive frame rate was 0.001%. Among the 240 polyps, 34 were sessile serrated lesions. The detection rate for sessile serrated lesions with the CAD system used in LCI mode was 100%. CONCLUSIONS: The new CAD system used in LCI mode achieved a 100% sensitivity per lesion and a negligible false-positive frame rate. Note that the new CAD system used in LCI mode also specifically allowed for detection of serrated lesions in all cases. Accordingly, the AI algorithm introduced here for the first time has the potential to dramatically improve the quality of colonoscopy.

An investigation of the diagnostic, predictive, and prognostic impacts of three colonic biopsy grading systems for acute graft versus host disease.

Acute graft versus host disease (aGvHD) is an important, life-threatening complication after allogeneic hematopoietic stem cell transplantation (alloHSCT). To investigate the value of multiple simultaneous colon biopsies in improving diagnostic accuracy in patients with aGvHD, we retrospectively analyzed 157 patients after alloHSCT. The biopsies were evaluated individually using three established histological grading systems (Lerner, Sale, and Melson). The maximum, minimum, median, and mean histological aGvHD grades were calculated for each patient, and the results were correlated with the Glucksberg grade of clinical manifestation of GvHD, steroid therapy status, and outcome. We found that multiple colon biopsies enhanced diagnostic sensitivity. Moreover, higher histological grades correlated with steroid therapy initiation and refractoriness; the latter particularly occurred when advanced damage was present in all samples and healthy colon mucosa was reduced or absent. On multivariate analysis, the minimal Lerner and Glucksberg grades for intestinal aGvHD were significantly associated with steroid treatment failure. Ninety-nine patients died. The median survival was 285 days after the biopsies were taken. Fifteen patients died from relapse of their underling disorder and 84 from other causes, mostly infection (53 patients) and GvHD (14 patients). Multivariate analysis revealed a significant association between none-relapse mortality and the mean Lerner grade, minimum Melson grade, Glucksberg organ stage, and platelet counts. Thus, we found the Lerner system to be superior to the other grading methods in most instances and histologic evaluation of multiple simultaneously obtained biopsies from the colon to result in a higher diagnostic yield, which helps plan systemic steroid treatment while predicting treatment response and outcome.

Immunohistochemical markers for histopathological diagnosis and differentiation of acute cutaneous graft-versus-host disease.

Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to SJS/TEN, MDE and healthy skin, aGvHD biopsies contained greater numbers of CD4+ and CD8+ T cells. The majority of CD4+ T-helper cells were localized in the upper dermis, whereas cytotoxic CD8+ T cells were found in the epidermis. Increased numbers of CD56+ natural killer (NK) cells in the upper dermis of aGvHD skin (p = 0.007) were not observed in controls or SJS/TEN and MDE. There were no differences in elafin staining between aGvHD and the latter two conditions. Acute GvHD appears to have a distinct inflammatory cell profile (T cells/NK cells) that may aid establishing in a more accurate diagnosis, especially when used to rule out differential diagnoses such as SJS/TEN or MDE.

Definitive evidence for Club cells as progenitors for mutant Kras/Trp53-deficient lung cancer.

Accumulating evidence suggests that both the nature of oncogenic lesions and the cell-of-origin can strongly influence cancer histopathology, tumor aggressiveness and response to therapy. Although oncogenic Kras expression and loss of Trp53 tumor suppressor gene function have been demonstrated to initiate murine lung adenocarcinomas (LUADs) in alveolar type II (AT2) cells, clear evidence that Club cells, representing the second major subset of lung epithelial cells, can also act as cells-of-origin for LUAD is lacking. Equally, the exact anatomic location of Club cells that are susceptible to Kras transformation and the resulting tumor histotype remains to be established. Here, we provide definitive evidence for Club cells as progenitors for LUAD. Using in vivo lineage tracing, we find that a subset of Kras12V -expressing and Trp53-deficient Club cells act as precursors for LUAD and we define the stepwise trajectory of Club cell-initiated tumors leading to lineage marker conversion and aggressive LUAD. Our results establish Club cells as cells-of-origin for LUAD and demonstrate that Club cell-initiated tumors have the potential to develop aggressive LUAD.

Lethal systemic and brain infection caused by Prototheca zopfii algae in a patient with acute myeloid leukemia.

Systemic protothecosis is an exceptionally rare cause of sepsis with few available therapeutic options. Here, we report on a female patient with newly diagnosed acute myeloid leukemia who died after start of chemotherapy due to a severe septic shock caused by a disseminated systemic infection with Prototheca zopfii including encephalitis.

Thymic Hyperplasia with Lymphoepithelial Sialadenitis (LESA)-Like Features: Strong Association with Lymphomas and Non-Myasthenic Autoimmune Diseases.

Thymic hyperplasia (TH) with lymphoepithelial sialadenitis (LESA)-like features (LESA-like TH) has been described as a tumor-like, benign proliferation of thymic epithelial cells and lymphoid follicles. We aimed to determine the frequency of lymphoma and autoimmunity in LESA-like TH and performed retrospective analysis of cases with LESA-like TH and/or thymic MALT-lymphoma. Among 36 patients (21 males) with LESA-like TH (age 52 years, 32-80; lesion diameter 7.0 cm, 1-14.5; median, range), five (14%) showed associated lymphomas, including four (11%) thymic MALT lymphomas and one (3%) diffuse large B-cell lymphoma. One additional case showed a clonal B-cell-receptor rearrangement without evidence of lymphoma. Twelve (33%) patients (7 women) suffered from partially overlapping autoimmune diseases: systemic lupus erythematosus (n = 4, 11%), rheumatoid arthritis (n = 3, 8%), myasthenia gravis (n = 2, 6%), asthma (n = 2, 6%), scleroderma, Sjögren syndrome, pure red cell aplasia, Grave's disease and anti-IgLON5 syndrome (each n = 1, 3%). Among 11 primary thymic MALT lymphomas, remnants of LESA-like TH were found in two cases (18%). In summary, LESA-like TH shows a striking association with autoimmunity and predisposes to lymphomas. Thus, a hematologic and rheumatologic workup should become standard in patients diagnosed with LESA-like TH. Radiologists and clinicians should be aware of LESA-like TH as a differential diagnosis for mediastinal mass lesions in patients with autoimmune diseases.

Molecular endoscopic imaging for the detection of Barrett's metaplasia using biodegradable inorganic nanoparticles: An ex-vivo pilot study on human tissue.

BACKGROUND AND STUDY AIMS: Despite major technical advancements, endoscopic surveillance for detecting premalignant lesions in Barrett's esophagus is challenging because of their flat appearance with only subtle morphological changes. Molecular endoscopic imaging (MEI) using nanoparticles (NPs), coupled with fluorescently labeled antibody permits visualization of disease-specific molecular alterations. The aim of this ex vivo study was to assess the diagnostic applicability of MEI with NPs to detect Barrett's metaplasia. PATIENTS AND METHODS: Seven patients undergoing endoscopic surveillance of known Barrett's esophagus were recruited. Freshly resected biopsy specimens were incubated with NPs coupled with FITC labeled Muc-2 antibodies and examined with MEI. Fluorescence intensity from Barrett's mucosa and control specimens were compared, followed by histological confirmation. RESULTS: Fluorescence signals, indicating the presence of goblet cells, were noted for traditional MEI using Muc-2 antibodies in Barrett's intestinal metaplasia. Significantly stronger fluorescence signals were achieved with NPs coupled with FITC-conjugated Muc-2 antibodies. The results of MEI with NPs for the prediction of Barrett's metaplasia correlated with the final histopathological examination in all the cases. CONCLUSIONS: Highly-specific NPs detected Barrett's metaplasia more efficiently than conventional MEI in this first feasibility study. MEI was as effective as standard histopathology for identifying Muc-2 containing goblet cells for diagnosis of Barrett's metaplasia. (DRKS-ID: DRKS00017747).

Histologic diagnosis and grading of esophageal acute graft-versus-host disease.

Acute intestinal graft-versus-host disease (GvHD) is a serious threat after allogeneic hematopoietic stem cell transplantation (alloHSCT). Although criteria for the histological diagnosis and grading of GvHD are well established for most parts of the gastrointestinal tract, evidence-based criteria have not yet been defined for the esophagus. Here, we evaluated esophageal biopsies obtained from 51 patients who underwent alloHSCT and compared the findings with those within the stomach and duodenum. In 32 of 51 biopsy samples of the esophagus, we identified a continuum of histological features of acute GvHD, ranging from vacuolar degeneration and single-cell apoptosis to the formation of clefts and mucosa denudation in advanced cases. These findings correlated with GvHD involving the stomach and duodenum and the clinical manifestations of GvHD in other organs. We therefore conclude that acute GvHD and esophageal GvHD can be diagnosed and graded histologically. Our findings may help to establish the histological diagnosis of acute GvHD using endoscopic biopsies from the esophagus and to explain the alterations observed in the esophageal mucosa in patients after alloHSCT.

Diagnosis and grading of acute graft-versus-host disease in endoscopic biopsy series throughout the upper and lower intestine in patients after allogenic hematopoietic stem cell transplantation: a systematic approach.

Intestinal graft-versus-host disease (GvHD) is a potentially life-threatening condition after allogenic hematological stem cell transplantation (alloHSCT). Although efforts have been made to determine the best sites for endoscopic biopsies, an approach involving all accessible anatomical regions is lacking. We investigated 22 complete biopsy series, each comprising biopsies from 10 different sites of the upper and lower intestine from 21 patients. The majority of biopsies investigated revealed histological signs of acute GvHD. The highest incidence and most advanced grades of acute GvHD were found in the right colon and terminal ileum. We detected significant correlations between crypt or gland loss and histological grades of acute GvHD, and between the number of sites with crypt or gland loss and the time elapsed since alloHSCT. Our results indicate that the most informative biopsies for GvHD diagnosis were those from the right colon and terminal ileum, and from the duodenum for the upper intestine.