High prevalence and functional effects of serum antineuronal antibodies in patients with gastrointestinal disorders.

BACKGROUND: Antineuronal antibodies can be associated with both gastrointestinal (GI) and brain disorders. For example, antibodies against the potassium channel subunit dipeptidyl-peptidase-like protein-6 (DPPX) bind to neurons in the central nervous system (CNS) and myenteric plexus and cause encephalitis, commonly preceded by severe unspecific GI symptoms. We therefore investigated the prevalence of antineuronal antibodies indicative of treatable autoimmune CNS etiologies in GI patients. METHODS: Serum samples of 107 patients (Crohn's disease n = 42, ulcerative colitis n = 16, irritable bowel syndrome n = 13, others n = 36) and 44 healthy controls were screened for anti-DPPX and further antineuronal antibodies using immunofluorescence on rat brain and intestine and cell-based assays. Functional effects of high-titer reactive sera were assessed in organ bath and Ussing chamber experiments and compared to non-reactive patient sera. KEY RESULTS: Twenty-one of 107 patients (19.6%) had antibodies against the enteric nervous system, and 22 (20.6%) had anti-CNS antibodies, thus significantly exceeding frequencies in healthy controls (4.5% each). Screening on cell-based assays excluded established antienteric antibodies. Antibody-positive sera were not associated with motility effects in organ bath experiments. However, they induced significant, tetrodotoxin (TTX)-insensitive secretion in Ussing chambers compared to antibody-negative sera. CONCLUSIONS & INFERENCES: Antineuronal antibodies were significantly more frequent in GI patients and associated with functional effects on bowel secretion. Future studies will determine whether such antibodies indicate patients who might benefit from additional antibody-directed therapies. However, well-characterized encephalitis-related autoantibodies such as against DPPX were not detected, underlining their rarity in routine cohorts.

[Efficacy, tolerability, and safety of cannabinoids in gastroenterology: A systematic review]. / Wirksamkeit, Verträglichkeit und Sicherheit von Cannabinoiden in der Gastroenterologie : Eine systematische Übersichtsarbeit.

BACKGROUND: The medical use of cannabis is discussed in gastroenterology for inflammatory bowel diseases (IBD), irritable bowel syndrome (IBS), and chronic pancreatitis. MATERIALS AND METHODS: A systematic literature search until March 2015 was performed in the databases Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, www.cannabis-med.org , and clinicaltrials.gov. Randomized controlled trials (RCT) investigating herbal cannabis and/or pharmaceutical cannabinoids in IBD, IBS, or chronic pancreatitis with a study duration of ≥ 4 weeks and a sample size of at least n = 10 per study arm were identified. Clinical outcomes comprised efficacy (pain, nausea, appetite/weight, diarrhea, health-related quality of life, and remission rates for IBD), tolerability (drop-out rate due to side effects), and safety (severe side effects). Methodology quality of RCTs was evaluated with the Cochrane Risk of Bias Tool. RESULTS: Only one RCT treating 21 patients with Crohn's disease and herbal cannabis was identified. The study revealed no significant differences of remission rate because of low statistical power. However, there was a clear tendency for less abdominal pain and improved appetite with medical cannabis. The methodological risk of the study was high. Furthermore, results of two RCTs investigating synthetic cannabis in IBD and chronic pancreatitis, respectively, have not yet been released. No RCT for IBS was found. Several case reports described cannabis-induced acute pancreatitis. CONCLUSIONS: Cannabis may be useful for symptom relief in Crohn's disease such as pain, nausea, and loss of appetite. However, studies with high methodological quality, sufficient sample size, and study duration are mandatory to determine potential therapeutic effects and risks of cannabis in gastroenterology. Currently, use of tetrahydrocannabinol to alleviate symptoms such as pain and appetite loss in Crohn's disease should only be considered in individual patients after failure of established medical therapies and only after careful risk-benefit assessment.

High frequency of intrathecal immunoglobulin synthesis in epilepsy so far classified cryptogenic.

BACKGROUND AND PURPOSE: The influence of the immune system on seizures and epileptogenesis has been increasingly considered, in particular the role of autoantibodies. In this study, we aimed to determine the frequency of intrathecal antibody synthesis in the cerebrospinal fluid (CSF) compartment of patients with epilepsy. METHODS: In a retrospective cohort study trial in a university hospital neurology department, 164 well-characterized patients with different etiologies of seizures and epilepsies, and 77 control patients were included. RESULTS: CSF-specific immunoglobulin (IgG, IgM and IgA) synthesis was significantly (P < 0.0001) more frequent in patients with epilepsy (34.1%) compared with age- and sex-matched controls (2.6%). The highest incidence of intrathecal Ig synthesis was detected in patients with encephalitis-related acute symptomatic seizures (86.7%), but also in patients with focal epilepsy so far classified cryptogenic (45.2%). Antibody synthesis was not related to the number of CSF white blood cells. CONCLUSIONS: Humoral immune activation in the CSF compartment was detected in one-third of patients with epilepsy, besides acute symptomatic seizures particularly frequent in cryptogenic epilepsy--an etiology so far defined as not having a detectable cause. Systematic prospective clinical and experimental trials are required to identify antigenic targets and select appropriate patients for which immunotherapy might offer new causal therapeutic options.