Mutant KRAS as a prognostic biomarker after hepatectomy for rectal cancer metastases: Does the primary disease site matter?

BACKGROUND: The prognostic implication of mutant KRAS (mKRAS) among patients with primary disease in the rectum remains unknown. METHODS: From 2000 to 2018, patients undergoing hepatectomy for colorectal liver metastases at 10 collaborating international institutions with documented KRAS status were surveyed. RESULTS: A total of 834 (65.8%) patients with primary colon cancer and 434 (34.2%) patients with primary rectal cancer were included. In patients with primary colon cancer, mKRAS served as a reliable prognostic biomarker of poor overall survival (OS) (hazard ratio [HR]: 1.58, 95% CI 1.28-1.95) in the multivariable analysis. Although a trend towards significance was noted, mKRAS was not found to be an independent predictor of OS in patients with primary rectal tumors (HR 1.34, 95% CI 0.98-1.80). For colon cancer, the specific codon impacted in mKRAS appears to reflect underlying disease biology and oncologic outcomes, with codon 13 being associated with particularly poor OS in patients with left-sided tumors (codon 12, HR 1.56, 95% CI 1.22-1.99; codon 13, HR 2.10 95% CI 1.43-3.08;). Stratifying the rectal patient population by codon mutation did not confer prognostic significance following hepatectomy. CONCLUSIONS: While the left-sided colonic disease is frequently grouped with rectal disease, our analysis suggests that there exist fundamental biologic differences that drive disparate outcomes. Although there was a trend toward significance of KRAS mutations for patients with primary rectal cancers, it failed to achieve statistical significance.

S. Enteritidis and S. Typhimurium Harboring SPI-1 and SPI-2 Are the Predominant Serotypes Associated With Human Salmonellosis in Saudi Arabia.

Non-typhoidal Salmonella (NTS) strains are Gram negative bacterial pathogens that are associated with foodborne illness worldwide. During the process of infection, Salmonella uses two molecular injectisomes known as Type 3 Secretion Systems (T3SS) to secrete virulence factors that are encoded by Salmonella Pathogenicity Island-1 (SPI-1) and SPI-2 into host cells. These secretion systems play a major role in virulence, as shown in various animal models, but little is known about their role in human infections. In Saudi Arabia, NTS strains frequently cause human infections but data regarding these pathogenic strains is fairly limited. The aim of this study was to characterize Salmonella human clinical isolates in Riyadh, Saudi Arabia, by determining their serotype, testing for the presence of SPI-1 and SPI-2 genes and to determine the antibiotic resistance profiles of these strains. Using the rapid Check and Trace Salmonella™ (CTS) system our results demonstrate that S. Enteritidis and S. Typhimurium were the predominant serovars, followed by S. Livingstone, S. Kentucky and S. Poona among a list of 36 serovars reported for the first time in the country. In addition, SPI-1 genes were detected in 99% of the isolates, while the sifA gene (SPI-2) was not detected in 13.5% of the isolates. These results suggest that both the SPI-1 and SPI-2 virulence determinants are important for human infection. Moreover, we report the presence of a Multi-Drug (MDR) carbapenem resistant S. Kentucky isolate harboring the blaOXA-48 gene not reported previously in Saudi Arabia.

Examining the Link between Biofilm Formation and the Ability of Pathogenic Salmonella Strains to Colonize Multiple Host Species.

Salmonella are important pathogens worldwide and a predominant number of human infections are zoonotic in nature. The ability of strains to form biofilms, which is a multicellular behavior characterized by the aggregation of cells, is predicted to be a conserved strategy for increased persistence and survival. It may also contribute to the increasing number of infections caused by ingestion of contaminated fruits and vegetables. There is a correlation between biofilm formation and the ability of strains to colonize and replicate within the intestines of multiple host species. These strains predominantly cause localized gastroenteritis infections in humans. In contrast, there are salmonellae that cause systemic, disseminated infections in a select few host species; these "invasive" strains have a narrowed host range, and most are unable to form biofilms. This includes host-restricted Salmonella serovar Typhi, which are only able to infect humans, and atypical gastroenteritis strains associated with the opportunistic infection of immunocompromised patients. From the perspective of transmission, biofilm formation is advantageous for ensuring pathogen survival in the environment. However, from an infection point of view, biofilm formation may be an anti-virulence trait. We do not know if the capacity to form biofilms prevents a strain from accessing the systemic compartments within the host or if loss of the biofilm phenotype reflects a change in a strain's interaction with the host. In this review, we examine the connections between biofilm formation, Salmonella disease states, degrees of host adaptation, and how this might relate to different transmission patterns. A better understanding of the dynamic lifecycle of Salmonella will allow us to reduce the burden of livestock and human infections caused by these important pathogens.

Kinect-based choice reaching and stepping reaction time tests for clinical and in-home assessment of fall risk in older people: a prospective study.

BACKGROUND: Quick protective reactions such as reaching or stepping are important to avoid a fall or minimize injuries. We developed Kinect-based choice reaching and stepping reaction time tests (Kinect-based CRTs) and evaluated their ability to differentiate between older fallers and non-fallers and the feasibility of administering them at home. METHODS: A total of 94 community-dwelling older people were assessed on the Kinect-based CRTs in the laboratory and were followed-up for falls for 6 months. Additionally, a subgroup (n = 20) conducted the Kinect-based CRTs at home. Signal processing algorithms were developed to extract features for reaction, movement and the total time from the Kinect skeleton data. RESULTS: Nineteen participants (20.2 %) reported a fall in the 6 months following the assessment. The reaction time (fallers: 797 ± 136 ms, non-fallers: 714 ± 89 ms), movement time (fallers: 392 ± 50 ms, non-fallers: 358 ± 51 ms) and total time (fallers: 1189 ± 170 ms, non-fallers: 1072 ± 109 ms) of the reaching reaction time test differentiated well between the fallers and non-fallers. The stepping reaction time test did not significantly discriminate between the two groups in the prospective study. The correlations between the laboratory and in-home assessments were 0.689 for the reaching reaction time and 0.860 for stepping reaction time. CONCLUSION: The study findings indicate that the Kinect-based CRT tests are feasible to administer in clinical and in-home settings, and thus represents an important step towards the development of sensor-based fall risk self-assessments. With further validation, the assessments may prove useful as a fall risk screen and home-based assessment measures for monitoring changes over time and effects of fall prevention interventions.

Clinical presentation and long-term outcome of 144 patients with microscopic polyangiitis in a monocentric German cohort.

OBJECTIVE: To evaluate the clinical presentation and long-term outcome of a vasculitis centre cohort of patients with microscopic polyangiitis (MPA) with respect to organ manifestations, treatment, chronic damage and mortality. METHODS: We performed a retrospective chart review at our vasculitis referral centre. MPA patients admitted between 1991 and 2013 classified by a modified European Medicines Agency algorithm were diagnosed and treated according to a standardized interdisciplinary approach. RESULTS: Comprehensive data from standardized interdisciplinary workups was available for 144 patients (median follow-up 72 months). The overall standardized mortality ratio was 1.40 (95% CI 0.91, 2.07; P = 0.13). We observed a higher mortality [hazard ratio (HR) 4.04 (95% CI 1.21, 13.45), P = 0.02] in 17 patients with MPA-associated fibrosing interstitial lung disease (ILD) and 56 patients with peripheral nervous system involvement [HR 5.26 (95% CI 1.10, 25.14), P = 0.04] at disease onset. One hundred and fifteen patients (79.9%) responded to the initial treatment. Sixty-one (42.3%) achieved complete remission and 54 (37.5%) achieved partial remission. Twenty (13.9%) showed a refractory disease course. CONCLUSION: MPA patients at our tertiary rheumatology referral centre seemed to have a less severe phenotype resulting in a less severe disease course and better outcome than reported in other cohorts. Fibrosing ILD was significantly associated with mortality in this cohort.

Kinect-Based Five-Times-Sit-to-Stand Test for Clinical and In-Home Assessment of Fall Risk in Older People.

BACKGROUND: Accidental falls remain an important problem in older people. The five-times-sit-to-stand (5STS) test is commonly used as a functional test to assess fall risk. Recent advances in sensor technologies hold great promise for more objective and accurate assessments. OBJECTIVE: The aims of this study were: (1) to examine the feasibility of a low-cost and portable Kinect-based 5STS test to discriminate between fallers and nonfallers and (2) to investigate whether this test can be used for supervised clinical, supervised and unsupervised in-home fall risk assessments. METHODS: A total of 94 community-dwelling older adults were assessed by the Kinect-based 5STS test in the laboratory and 20 participants were tested in their own homes. An algorithm was developed to automatically calculate timing- and speed-related measurements from the Kinect-based sensor data to discriminate between fallers and nonfallers. The associations of these measurements with standard clinical fall risk tests and the results of supervised and unsupervised in-home assessments were examined. RESULTS: Fallers were significantly slower than nonfallers on Kinect-based measures. The mean velocity of the sit-to-stand transitions discriminated well between the fallers and nonfallers based on 12-month retrospective fall data. The Kinect-based measures collected in the laboratory correlated strongly with those collected in the supervised (r = 0.704-0.832) and unsupervised (r = 0.775-0.931) in-home assessments. CONCLUSION: In summary, we found that the Kinect-based 5STS test discriminated well between the fallers and nonfallers and was feasible to administer in clinical and supervised in-home settings. This test may be useful in clinical settings for identifying high-risk fallers for further intervention or for regular in-home assessments in the future.

Pathogenesis of anti-neutrophil cytoplasmic antibody-associated vasculitis: challenges and solutions 2014.

Anti-neutrophil cytoplasmic autoantibodies (ANCA) with specificity for proteinase 3 (PR3-ANCA) or myeloperoxidase (MPO-ANCA) are a defining feature of ANCA-associated vasculitides (AAV). They play a pivotal role in disease pathophysiology and have strongly improved early diagnosis and treatment of these infrequent, but potentially fatal diseases. Neutrophils and their products are major players in initiating the autoimmune response and tissue destruction in vasculitic as well as granulomatous inflammation. This review highlights recent findings on old and novel players (ANCA, neutrophils, neutrophil extracellular traps, fibroblasts, immune cells and complement) and puts them into context with the current understanding of disease mechanisms in AAV.

Plasma cells within granulomatous inflammation display signs pointing to autoreactivity and destruction in granulomatosis with polyangiitis.

INTRODUCTION: Plasma cells residing in inflamed tissues produce antibodies in chronic inflammatory and systemic autoimmune diseases. This study examined if plasma cells, located within inflamed nasal tissue in granulomatosis with polyangiitis (GPA), express features potentially associated with the autoimmune and destructive character of this disease. METHODS: Ig gene mutation patterns of individual tissue-derived plasma cells from GPA (n = 5) were analyzed, by using laser-assisted microdissection followed by semi-nested polymerase chain reaction (PCR). Signs of B-lymphocyte maturation (ectopic lymphoid structures, ELS) and survival (a proliferation-inducing ligand, APRIL; B-cell maturation antigen, BCMA; transmembrane-activator and calcium modulator and cyclophilin interactor, TACI; receptor activator of nuclear factor κB ligand, RANKL) were examined in nasal tissues or serum, respectively, by using immunohistochemistry/fluorescence and enzyme-linked immunosorbent assay, ELISA. RESULTS: Plasma-cell derived Ig genes (light- and heavy-chain pairs, n = 4; heavy chains, n = 33) resembled mutation patterns seen in other autoimmune diseases, predominantly displaying selection against replacement mutations within the framework region of Ig genes (10 of 15), which is responsible for structural integrity. Ectopic lymphoid structures were similar between GPA and a disease control (that is, unspecific chronic rhinosinusitis. However, histomorphologic features distinguishing GPA from rhinosinusitis (that is, neutrophilic microabscess and granuloma) expressed considerable amounts of membrane-associated and secreted APRIL, respectively. The latter was co-localized with CD138 and found in close proximity to cells expressing IgG, TACI, and BCMA. Interestingly, plasma cells strongly expressed receptor activator of nuclear factor κB ligand (RANKL), apart from fibroblast-like cells. CONCLUSIONS: Plasma cells within granulomatous inflammation appear to display features that might be required for autoreactivity and, possibly, RANKL-mediated destruction in GPA.

Doubled prevalence rates of ANCA-associated vasculitides and giant cell arteritis between 1994 and 2006 in northern Germany.

OBJECTIVES: The aim of this study was to investigate the period prevalences of ANCA-associated vasculitides (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic GPA (EGPA)/Churg-Strauss and GCA, in an urban and rural population in northern Germany in 2006 and to compare the data with our previous study performed in 1994. METHODS: We identified of all patients with AAV or GCA via questionnaires to all hospital departments, physicians, health insurance providers, pension funds, reference laboratories for autoimmune diseases and death registries in Luebeck (city) and the rural region of Segeberg (population 468 962) between January and December 2006. The type of vasculitis, gender, year of birth, postal code and death were documented and re-evaluated. RESULTS: One-hundred and fifty patients were identified, indicating a prevalence of 320 per million inhabitants for the complete catchment area (95% CI 285, 355). GCA was more prevalent than AAV: 171 (146, 197) vs 149 (126, 174). GCA and AAV have almost doubled since 1994. GCA increased from 240 (164, 315) to 440 (399, 481) per million in the population ≥ 50 years of age and AAV increased from 74 to 149 cases per million. GCA and AAV were more prevalent in the urban compared with the rural region. CONCLUSION: The prevalence rates of AAV and GCA almost doubled from 1994 to 2006 for this region with a stable population and using an identical study design. Increased awareness has led to an earlier diagnosis of systemic vasculitis and improved activity-adapted treatment mostly based on randomized controlled trials has led to longer survival. Aspects such as environmental factors and exposure to certain substances need further research.

Non-biologic remission maintenance therapy in adult patients with ANCA-associated vasculitis: a systematic review and network meta-analysis.

OBJECTIVE: To determine the comparative efficacy of non-biologic treatments for remission maintenance in ANCA-associated vasculitis. METHODS: We identified all randomized trials comparing leflunomide, azathioprine, methotrexate or mycophenolate mofetil in adult patients with granulomatosis with polyangiitis or microscopic polyangiitis. Relapse-free survival was compared through hazard ratios (HR) using a Bayesian fixed-effects network meta-analysis. Multiple sensitivity analyses were performed to explore biases identified in one trial using original trial data. RESULTS: Three trials were available (leflunomide-methotrexate, methotrexate- azathioprine, azathioprine-mycophenolate). Mycophenolate was inferior to all treatments, although the 95% credible interval (CrI) of the HR relative to methotrexate crossed 1. Leflunomide was superior to azathioprine (HR 0.43 [95% CrI: 0.14-1.3]) and methotrexate (HR 0.47 [95% CrI: 0.18-1.2]), although the 95% CrI also crossed 1. There was a 90% probability that leflunomide was the best treatment. After down weighting the effect of leflunomide vs. methotrexate for early trial termination and slow MTX dose escalation, there remained a 55% probability leflunomide was best. CONCLUSION: Based on indirect evidence, leflunomide is effective in maintaining remission in granulomatosis with polyangiitis or microscopic polyangiitis relative to other non-biologic treatments. Further randomized trials of leflunomide are needed for confirmation.

Treatment of ANCA-associated vasculitis.

Antineutrophil cytoplasmic autoantibody (ANCA)-associated diseases are small-vessel vasculitides, encompassing granulomatosis with polyangiitis (formerly Wegener's granulomatosis), microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis. Once considered life-threatening diseases, the introduction of stage-adapted immunosuppressive therapy and medications with decreased toxicity has improved patients' survival. Treatment is biphasic, consisting of induction of remission (3-6 months) for rapid control of disease activity and maintenance of remission (at least 18 months) to prevent disease relapse using therapeutic alternatives that have reduced toxicity. This Review summarizes current treatment strategies for these diseases, with a special focus on long-term follow-up data from key randomized controlled trials and new developments in remission induction and maintenance therapy. Current treatment strategies have substantial short-term and long-term adverse effects, and relapses are frequent; thus, less-toxic and more-effective approaches are needed. Moreover, the optimal intensity and duration of maintenance therapy remains under debate. Clinical trials have traditionally considered ANCA-associated vasculitides as a single disease entity. However, future studies must stratify participants according to their specific disease, clinical features (different types of organ manifestation, PR3-ANCA or MPO-ANCA positivity) and disease severity.

Granuloma in ANCA-associated vasculitides: another reason to distinguish between syndromes?

The 2012 renewed Chapel Hill Consensus Conference (CHCC) officially named three clinicopathological entities, i.e. granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA), and microscopic polyangiitis (MPA), as major variants of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). Recent genetic and cohort studies revealed the need for further differentiation between the entities, for example regarding differences in outcome. As well as ANCA reactivity, upper and lower airway disease were found to be differentiating factors for AAV variants, improving prognostic ability regarding relapse prediction and associated clinical features. Extravascular granulomatosis, or "granuloma", which describes both clinically relevant granulomatous manifestations and histopathologically documented granulomatous inflammation, is characteristic of localized and systemic GPA, but not MPA. This review summarizes new knowledge regarding granuloma in the head and neck region of AAV, its histomorphological equivalents in the upper and lower respiratory tract, and evidence for a granulomatous phenotype of a persistent localized GPA variant. This comprises the development of disease activity and damage scores for extravascular lesions in the ear, nose, and throat (ENT) regions, and imaging techniques. In addition, findings linking extravascular manifestations to granulomatous inflammation are described. We hypothesize that, as for ANCA, necrotizing granulomatous inflammation and its clinical manifestations are discriminators, assisting subclassification of AAV and/or GPA subphenotypes which will be useful both for designing clinical trials and for treating patients successfully.

Current understanding of the pathogenesis of granulomatosis with polyangiitis (Wegener's).

Granulomatosis with polyangiitis (Wegener's) (GPA) is a multisystem disease of unknown etiology, characterized by granulomata of the respiratory tract and systemic necrotizing vasculitis. Antineutrophil cytoplasmic antibodies (ANCA) with specificity for proteinase 3 (PR3) are a defining feature of this disease. GPA usually starts as a granulomatous disease of the respiratory tract and, in the majority of patients, progresses to systemic disease with PR3-ANCA-associated vasculitis. Today, epidemiological evidence indicates that GPA develops as a result of complex gene-environment interactions. The nature of these risk factors and pathogenic mechanisms involved, however, are only just beginning to be understood. Clinical data and in vitro experimental results point to the pathogenic pathways involved in tissue lesion development, in which ANCA, cellular immunity, neutrophils extracellular traps, fibroblasts, vascular endothelial cells and inflammatory mediators play a major role. Today, the pathophysiological significance of PR3-ANCA is still unclear and the pathogenic pathways leading to granuloma formation are not explained. New data unexpectedly suggest that the destruction of nasal cartilage in GPA is mainly mediated by fibroblasts that can be blocked by corticosteroids.

Toll-like receptor TLR2 and TLR9 ligation triggers neutrophil activation in granulomatosis with polyangiitis.

OBJECTIVE: The aim of the study was to characterize the expression of TLR2, TLR4 and TLR9 in PMNs of patients with granulomatosis with polyangiitis (GPA) and to elucidate the role of these receptors in GPA with respect to neutrophil activation. METHODS: The expression of TLR2, TLR4 and TLR9 was determined on ex vivo PMNs in whole blood samples of GPA patients (n = 35) and healthy controls (HCs) (n = 24). Isolated PMNs were stimulated in vitro with TLR agonists and assessed for degranulation, membrane proteinase 3 (mPR3) expression, soluble l-selectin shedding and cytokine production (IL-8) in five GPA patients and five HCs. The priming effects of TLR2 and TLR9 ligation were assessed by measurement of serine protease activity after stimulation with PR3-ANCA. RESULTS: There were no significant differences in the ex vivo expression of TLRs on PMNs in HCs and GPA patients. Stimulation of TLR4 and TLR9 induced MPO release, stimulation with TLR2, TLR4 and TLR9 ligands elicited IL-8 production and stimulation of TLR2 and TLR9 led to an upregulation in mPR3 expression on PMNs with no significant differences between GPA and HC after 1 or 24 h stimulation. Priming of PMNs with TLR2 and TLR9 ligands induced degranulation after subsequent stimulation with PR3-ANCA, which was comparable to priming with TNF-α. CONCLUSION: Expression of TLR2, TLR4 and TLR9 in PMNs and the TLR-induced activation of PMNs was comparable in GPA and HC. mPR3 upregulation by TLR2 and TLR9 stimulation and the priming effect of TLR ligands on PMNs may have a potential implication for triggering disease activity during infection in GPA.

Orbital masses in granulomatosis with polyangiitis are associated with a refractory course and a high burden of local damage.

OBJECTIVES: To identify and characterize patients with orbital masses in a monocentric cohort of 1142 GPA patients followed up from 1990 until the end of 2010 with regard to disease stage, local orbital inflammation, course of disease and outcome and to assess the efficacy of immunosuppressive treatment. METHODS: All GPA patients fulfilling ACR criteria or Chapel Hill Consensus Conference definitions or who had localized GPA and who developed orbital masses were evaluated regarding the course and outcome of the orbital masses (assessed by MRI, ophthalmologist and ENT specialist), all other clinical manifestations, disease stages, ANCA status, immunosuppression and its side effects and surgical procedures. RESULTS: Of 1142 GPA patients 58 developed orbital masses during a median follow-up of 101.5 months (range 23-255 months). Forty patients fulfilled the inclusion criteria and had complete clinical assessments [44% females, median age 43 (20-74) years, 85% ANCA positive]. Seventy-five per cent (29/40) had systemic disease when orbital masses occurred; both orbits were affected in 30%. Seventy-two per cent had evidence of infiltration from paranasal sinuses. Under highly potent immunosuppression (mostly CYC and glucocorticoids), 41% were refractory, 24% had unchanged activity, 24% showed a response and 8.1% had complete remission. Forty-four per cent had relapses of orbital masses. Seventy-two per cent developed visual impairment, 19% suffered blindness. Blindness was associated with a longer time to remission and a relapsing and refractory course. CONCLUSION: Orbital masses are a rare manifestation of GPA and are characterized by a refractory course and by a high rate of local damage. Patients with a refractory or relapsing course are at higher risk of developing blindness.

Treatment of ANCA-associated vasculitides (AAV).

Treatment of AAV follows the principle of a combined remission induction and maintenance strategy and is adapted in a stage and activity-adapted fashion. So far the combination therapy of glucocorticoids and conventional immunosuppressive drugs has mainly been used to control disease. This approach has led to a significant improvement in outcome in spite of persistently high early mortality rates of nearly 11% within the first year. Besides conventional treatment, biologics have emerged as a new treatment option. The paper summarizes the current evidence for the use of conventional therapy and biologics in AAV.