The role of small intestinal bacterial overgrowth in Parkinson's disease.

Parkinson's disease is associated with gastrointestinal motility abnormalities favoring the occurrence of local infections. The aim of this study was to investigate whether small intestinal bacterial overgrowth contributes to the pathophysiology of motor fluctuations. Thirty-three patients and 30 controls underwent glucose, lactulose, and urea breath tests to detect small intestinal bacterial overgrowth and Helicobacter pylori infection. Patients also underwent ultrasonography to evaluate gastric emptying. The clinical status and plasma concentration of levodopa were assessed after an acute drug challenge with a standard dose of levodopa, and motor complications were assessed by Unified Parkinson's Disease Rating Scale-IV and by 1-week diaries of motor conditions. Patients with small intestinal bacterial overgrowth were treated with rifaximin and were clinically and instrumentally reevaluated 1 and 6 months later. The prevalence of small intestinal bacterial overgrowth was significantly higher in patients than in controls (54.5% vs. 20.0%; P = .01), whereas the prevalence of Helicobacter pylori infection was not (33.3% vs. 26.7%). Compared with patients without any infection, the prevalence of unpredictable fluctuations was significantly higher in patients with both infections (8.3% vs. 87.5%; P = .008). Gastric half-emptying time was significantly longer in patients than in healthy controls but did not differ in patients based on their infective status. Compared with patients without isolated small intestinal bacterial overgrowth, patients with isolated small intestinal bacterial overgrowth had longer off time daily and more episodes of delayed-on and no-on. The eradication of small intestinal bacterial overgrowth resulted in improvement in motor fluctuations without affecting the pharmacokinetics of levodopa. The relapse rate of small intestinal bacterial overgrowth at 6 months was 43%. © 2013 Movement Disorder Society.

Diagnosis and Acute Treatment of Ischemic Stroke.

Stroke is defined as an acute cerebrovascular accident characterized by an interruption of vascular supply lasting more than 24 hours. Therapeutic goal, reassumed at the well-known "time is brain", is strictly focused on achieving timely restoration of cerebral blood flow at risk of infarction to reduce neurological complications. Consequently, time to treatment is the most important determinant of the efficacy of reperfusion. Current guidelines strongly recommend the use of intravenous thrombolysis with tissue plasminogen activator and endovascular thrombectomy to reach that goal. These therapies allow to obtain 1.9 million neurons saved per each minute of onset-to-reperfusion time and 4.2 days of extra healthy life and are crucial in the reduction of mortality and morbidity of ischemic stroke. Multidisciplinary collaboration involving a coordinated prehospital management and stroke team composed of physicians with expertise in emergency medicine, neurologists, radiologists, nurses, technicians, and laboratory personnel are essential for rapid triage and should guide clinical decisions to deliver the appropriate reperfusion therapy for each patient.

The role of methane in intestinal diseases.

The volume of human intestinal gas is about 200 ml, and it is derived from complex physiological processes including swallowed air, diffusion from bloodstream into the lumen, and particularly intraluminal production by chemical reactions and bacterial fermentation. Gas is continuously removed by eructation, anal evacuation, absorption through the intestinal mucosa, and bacterial consumption. More than 99% of it is composed of hydrogen, oxygen, carbon dioxide, nitrogen, and other odoriferous gases. Methane (CH4) production is detectable in about one third of healthy adult individuals. In the past years, several studies have been focused on CH4 metabolism at the intestinal level and on the putative association between this gas and the pathophysiology of organic and functional bowel disorders. An overview of the present knowledge about the physiology of CH4 metabolism and its role in intestinal diseases is provided in this report.

Intestinal permeability in cirrhotic patients with and without spontaneous bacterial peritonitis: is the ring closed?

OBJECTIVES: Impaired intestinal permeability (IP) may have a role in the pathogenesis of ascites and in spontaneous bacterial peritonitis (SBP) in patients with liver cirrhosis (LC). The aim of this study was to assess IP in LC patients with respect to healthy controls. METHODS: IP was evaluated by the (51)Cr-ethylenediaminetetraacetic acid ((51)Cr-EDTA) permeability test in 52 LC patients and in 48 sex- and age-matched controls. The presence of (51)Cr-EDTA was also evaluated in ascitic fluid after therapeutic paracentesis in all LC patients with ascites. RESULTS: An altered IP was found in 45% of LC patients compared with 4% of controls (P<0.00001). IP impairment was significantly associated with Child-Pugh status (75% of Child C patients vs. 39% of Child B and 22% of Child A patients), with the presence of ascites (60% in ascitic patients vs. 31% in nonascitic patients), and with a history of SBP (100% of patients with SBP vs. 50% of those without SBP). (51)Cr-EDTA was present in all ascitic samples obtained from patients with SBP compared with 22% of patients without SBP. CONCLUSIONS: IP derangement was a common finding in LC, especially in patients with more advanced disease (presence of ascites and history of SBP). The presence of (51)Cr-EDTA in ascites in patients with SBP suggests an altered permeability of splancnic vessels and/or peritoneal membranes. Further studies are required to assess (51)Cr-EDTA urine and ascite cutoffs to set up SBP preventive strategies.

Association between hypothyroidism and small intestinal bacterial overgrowth.

OBJECTIVES: Small intestinal bacterial overgrowth is defined as an abnormally high bacterial population level in the small intestine. Intestinal motor dysfunction associated with hypothyroidism could predispose to bacterial overgrowth. Luminal bacteria could modulate gastrointestinal symptoms and interfere with levothyroxine absorption. The aims of the present study were to assess the prevalence and clinical pattern of bacterial overgrowth in patients with a history of overt hypothyroidism and the effects of bacterial overgrowth decontamination on thyroid hormone levels. METHODS: A total of 50 consecutive patients with a history of overt hypothyroidism due to autoimmune thyroiditis was enrolled. Diagnosis of bacterial overgrowth was based on positivity to a hydrogen glucose breath test. Bacterial overgrowth positive patients were treated with 1,200 mg rifaximin each day for a week. A glucose breath test, gastrointestinal symptoms, and thyroid hormone plasma levels were reassessed 1 month after treatment. RESULTS: A total of 27 patients with a history of hypothyroidism demonstrated a positive result to the breath test (27 of 50, 54%), compared with two in the control group (two of 40, 5%). The difference was statistically significant (P < 0.001). Abdominal discomfort, flatulence, and bloating were significantly more prevalent in the bacterial overgrowth positive group. These symptoms significantly improved after antibiotic decontamination. Thyroid hormone plasma levels were not significantly affected by successful bacterial overgrowth decontamination. CONCLUSIONS: The history of overt hypothyroidism is associated with bacterial overgrowth development. Excess bacteria could influence clinical gastrointestinal manifestations. Bacterial overgrowth decontamination is associated with improved gastrointestinal symptoms. However, fermenting carbohydrate luminal bacteria do not interfere with thyroid hormone levels.

Small intestinal bacterial overgrowth: diagnosis and treatment.

Small intestinal bacterial overgrowth (SIBO) is a clinical condition characterized by a malabsorption syndrome due to an increase in microorganisms within the small intestine. The main mechanisms restricting bacterial colonization in the upper gut are the gastric acid barrier, mucosal and systemic immunity and intestinal clearance. When these mechanisms fail, bacterial overgrowth develops. Diarrhea, steatorrhea, chronic abdominal pain, bloating and flatulence are common symptoms and are similar to those observed in irritable bowel syndrome. Breath tests (glucose and/or lactulose breath tests) have been proposed as a sensitive and simple tool for the diagnosis of bacterial overgrowth, being non-invasive and inexpensive compared to the gold standard represented by the culture of intestinal aspirates. Antibiotic therapy is the cornerstone of SIBO treatment. Current SIBO treatment is based on empirical courses of broad-spectrum antibiotics since few controlled studies concerning the choice and duration of antibiotic therapy are available at present.

Gut microbiota and obesity.

Intestinal epithelium, mucosal immune system, and bacterial flora represent a morpho-functional system on dynamic balance responsible for the intestinal metabolic and trophic functions, and the regulation of mucosal and systemic host's immunity. Obesity is a pathological condition affecting a growing number of people especially in the Western countries resulting from the failure of the organism's energetic balance based on the perfect equality of income, waste, and storage. Recent evidences explain the mechanisms for the microbial regulation of the host's metabolism both in health and disease. In particular, animal studies have explained how quali-/quantitative changes in microflora composition are able to affect the absorption of the nutrients and the energy distribution. Antibiotics, prebiotics, probiotics, and symbiotics are the instruments utilized in the current clinical practice to modulate the intestinal bacterial flora in man both in health and pathologic conditions with promising preliminary results on prevention and therapy of obesity and related metabolic diseases.

The role of emergency ultrasound in the diagnosis of acute non-traumatic epigastric pain.

The epigastrium is the site where pain coming from both abdominal and extra-abdominal organs is frequently referred. Although acute or chronic diseases of the stomach, duodenum, liver, pancreas and biliary tree are the most common causes of acute epigastric pain, several other entities, potentially more severe, should also be suspected and investigated. Clinical bedside ultrasonography (US) is actually the first-line imaging in acute epigastric pain patients presenting to the hospital Emergency Department (ED) because it is rapid, noninvasive, relatively inexpensive and focused, repeatable and reliable. Moreover, the systematic use of emergency US as a complement to routine management might save economic resources by avoiding further costs for complications and substantially reducing the time for making an accurate diagnosis. The purpose of this paper is to review the US spectrum of the most common diseases responsible for acute epigastric pain onset. We also propose a focused, well codified US protocol, that we call the "$ approach", based on our clinical experience and the current literature for acute non-traumatic epigastric pain evaluation in an emergency setting. Its systematic application by the emergency physician may reduce the wait for diagnosis and the over-usage of second-line radiological techniques, including computed tomography, as well as to increase the diagnostic accuracy with potential benefits for patient (safety), physician (efficacy) and the institution (efficiency).

Rifaximin pharmacology and clinical implications.

Rifaximin is a semisynthetic, rifamycin-based non-systemic antibiotic, with a low gastrointestinal absorption and a good antibacterial activity. The antibacterial action covers Gram-positive and Gram-negative organisms, both aerobes and anaerobes. Its antimicrobial action is based on its property to bind to the beta-subunit of bacterial DNA-dependent RNA polymerase inhibiting, thereby, the bacterial RNA synthesis. Rifaximin contributes to restore gut microflora imbalance, becoming an important therapeutic agent in several organic and functional gastrointestinal diseases such as hepatic encephalopathy, small intestine bacterial overgrowth, inflammatory bowel disease and colonic diverticular disease. This antibiotic has the advantage of low microbial resistance and few systemic adverse events and is safe in all patient populations, including young children.

Rifaximin-based regimens for eradication of Helicobacter pylori: a pilot study.

BACKGROUND: Triple therapy is the treatment of choice for Helicobacter pylori-infected patients with an eradication rate ranging from 70 to 85%. Poor compliance and antibiotic resistance are the main causes of treatment failure. The aim of the present study was to assess the efficacy of rifaximin, a poorly absorbed antibiotic, for H. pylori eradication. METHODS: We enrolled 48 consecutive H. pylori-positive patients affected. They were randomized to receive two 7-day rifaximin-based triple therapies: rifaximin tablets 400 mg t.i.d., esomeprazole 40 mg o.d. and clarithromycin 500 mg b.i.d. (CRE) or levofloxacin 500 mg o.d. (LRE). H. pylori eradication was assessed using a (13)C-urea breath test 4 weeks after the end of therapy. Treatment compliance and the incidence of side effects were also evaluated. RESULTS: No dropouts were observed. The eradication rate both on intention-to-treat and per-protocol analysis did not show significant differences between groups: 58% (14/24 patients) in group 1 and 42% (10/24 patients) in group 2 (p = 0.24, OR 1.96, 95% CI 0.62-6.18). No significant differences in patients' compliance and incidence of side effects were found between groups. CONCLUSIONS: Rifaximin-based therapy showed optimal compliance but a limited eradication rate compared to standard first-line treatment. Further investigations are needed to evaluate different dosages and combinations.