Colonic Biopsies to Assess the Neuropathology of Parkinson's Disease and Its Relationship with Symptoms

The presence of Lewy bodies and Lewy neurites (LN) has been demonstrated in the enteric nervous system (ENS) of Parkinson's disease (PD) patients. The aims of the present research were to use routine colonoscopy biopsies (1) to analyze, in depth, enteric pathology throughout the colonic submucosal plexus (SMP), and (2) to correlate the pathological burden with neurological and gastrointestinal (GI) symptoms.A total of 10 control and 29 PD patients divided into 3 groups according to disease duration were included. PD and GI symptoms were assessed using the Unified Parkinson's Disease Rating Scale part III and the Rome III questionnaire, respectively. Four biopsies were taken from the ascending and descending colon during the course of a total colonoscopy. Immunohistochemical analysis was performed using antibodies against phosphorylated alpha-synuclein, neurofilaments NF 220 kDa (NF) and tyrosine hydroxylase (TH). The density of LN, labeled by anti-phosphorylated alpha-synuclein antibodies, was evaluated using a quantitative rating score. Lewy pathology was apparent in the colonic biopsies from 21 patients and in none of the controls. A decreased number of NF-immunoreactive neurons per ganglion was observed in the SMP of PD patients compared to controls. The amount of LN in the ENS was inversely correlated with neuronal count and positively correlated with levodopa-unresponsive features and constipation.Analysis of the ENS by routine colonoscopy biopsies is a useful tool for pre-mortem neuropathological diagnosis of PD, and also provides insight into the progression of motor and non-motor symptoms

Higher Serum Infliximab Concentrations Following Subcutaneous Dosing are Associated with Deep Remission in Patients with Inflammatory Bowel Disease

International audienceAbstract Background The relationship between subcutaneous infliximab [SC-IFX] concentrations and favourable therapeutic outcomes in patients with Crohn’s disease [CD] and ulcerative colitis [UC] remains elusive. Patients and Methods This cross-sectional study included consecutive adult patients with inflammatory bowel disease [IBD] treated with SC-IFX at a maintenance dose of 120 mg/2 weeks. Investigated therapeutic outcomes included sustained clinical remission; composite clinical and biomarker remission [clinical remission and C-reactive protein <5 mg/L]; biochemical remission [faecal calprotectin <250 µg/g]; and deep remission [clinical, biological, and biochemical remission]. Results Of 91 patients identified, 71 qualified for inclusion in the study [70% with CD; 27% with concomitant immunomodulators]. At the time of drug concentration measurement [median 13.5 months after switch], 55 [77%] patients had sustained clinical remission; n = 44 [62%] composite clinical and biomarker remission; n = 40 [56%] biochemical remission; and n = 31 [43%] deep remission. The mean SC-IFX concentrations were significantly higher in patients with sustained clinical remission [p = 0.014]; composite clinical and biomarker remission [p = 0.003]; biochemical remission [p < 0.001]; and deep remission [p < 0.001] compared to patients without having these outcomes. In multivariate analysis, SC-IFX concentration was the only factor independently associated with sustained clinical remission (odds ratio [OR]: 4.7, 95% confidence interval [CI]: 3.1–12.2, p = 0.005); clinical and biomarker remission [OR: 9.21, 95% CI: 6.09–18.7, p = 0.006]; biochemical remission [OR: 37, 95% CI: 14–39.3, p < 0.001]; and deep remission [OR: 29, 95% CI: 15.7–37.4, p < 0.001]. The optimal SC-IFX concentration cut-off associated with deep remission based on ROC analysis was 20 µg/mL [sensitivity: 0.91, specificity: 0.80, accuracy: 0.85]. Combination with an immunomodulator failed to improve SC-IFX pharmacokinetics. Conclusion Higher SC-IFX concentrations are associated with higher rates of favourable therapeutic outcomes in IBD patients. Serum SC-IFX concentrations >20 µg/mL were significantly associated with deep remission