Drug-induced gastrointestinal disorders

Review article: A practical approach to persistent gastrointestinal symptoms in inflammatory bowel disease in remission

BACKGROUND

Persistent gastrointestinal symptoms are prevalent in adult patients with inflammatory bowel disease (IBD), even when endoscopic remission is reached. These symptoms can have profound negative effects on the quality of life of affected patients and can be difficult to treat. They may be caused by IBD-related complications or comorbid disorders, but they can also be explained by irritable bowel syndrome (IBS)-like symptoms.

AIMS

To provide a practical step-by-step guide to diagnose and treat persistent gastrointestinal symptoms in patients with IBD in remission via a personalised approach.

METHODS

We scrutinised relevant literature on causes, diagnostics and treatment of persistent gastrointestinal symptoms (abdominal pain or discomfort, bloating, abdominal distension, diarrhoea, constipation and faecal incontinence) in patients with IBD in remission.

RESULTS

A graphical practical guide for several steps in diagnosing, identifying potential triggers and adequate treatment of persistent gastrointestinal symptoms in IBD in remission is provided based on supporting literature. The first part of this review focuses on the diagnostic and treatment approaches for potential IBD-related complications and comorbidities. The second part describes the approach to IBS-like symptoms in IBD in remission.

CONCLUSIONS

Persistent gastrointestinal symptoms in IBD in remission can be traced back to potential pathophysiological mechanisms in individual patients and can be treated adequately. For both IBD-related complications and comorbidities and IBS-like symptoms in IBD in remission, pharmacological, dietary, lifestyle or psychological treatments can be effective. A systematic and personalised approach is required to reduce the burden for patients, healthcare systems, and society.

Efficacy and Safety of Bacillus coagulans LBSC in Drug Induced Constipation Associated With Functional Gastrointestinal Disorder: A Double-Blind, Randomized, Interventional, Parallel, Controlled Trial a Clinical Study on Bacillus coagulans LBSC for Drug Induced Constipation Associated With FGIDs

Background

Active drugs and nutraceutical supplements commonly induce various gastrointestinal illnesses, and constipation is a major gastrointestinal symptom accompanied with functional gastrointestinal disorders. Drug-induced imbalance in gut microbiota may play critical role in such physiological disturbances. Probiotics have been known for resuming normal and healthy gut microbiome.

Objective

To investigate the clinical efficacy and safety of Bacillus coagulans LBSC in the treatment of drug induced constipation associated with functional gastrointestinal disorder (FGID) symptoms.

Methods

A prospective, interventional, randomized, double-blind, parallel, multi-arm, controlled trial with 168 patients experiencing drug induced constipation associated with FGID symptoms (DICAWFGID) screened through Rome IV criteria were randomized into 2 arms, i.e. placebo arm (n = 28) and atorvastatin, atenolol, metformin, amitriptyline, and calcium in test arm (n = 28/arm). Patients in both arms received similar dosages (1 g sachet, 3 times a day) for 35 days. The occurrence of constipation using Bristol Stool Form Scale, assessment of degree of constipation on 4-point Likert scale, occurrence of hard stool and degree of stool expulsion on 3-point scale, and defecation frequency were primary endpoints. While, secondary outcomes consisted of the changes in severity of FGID symptoms, visual analogue scale and tolerance to IP, along with reports of adverse events (AEs) and severe adverse events (SAEs).

Results

There was a significant reduction in occurrence of constipation (≥98.6% and P-value <0.05) in test arm over the placebo arm. Assessment of co-primary endpoints showed significant improvements in degree of stool consistency (P-value 0.0232; CI: 0.1870, 1.1629), borderline significantly superior in degree of stool expulsion (P-value 0.0553; CI: 0.0378, -0.4939), while the other co-primary efficacy endpoints displayed considerably improved advancement (non-significant, P-value ≥0.05). The intra group analysis of symptoms at start of treatment (SOT) and end of treatment (EOT) revealed a significant reduction in scores for occurrence of constipation and degree of constipation, whereas significant improvement in the scores for degree of stool consistency and degree of stool expulsion (P-value <0.001) after the intervention period. In secondary endpoints, the processed responses clearly signified a considerable positive improvement (non-significant, P-value ≥0.05) in other symptoms of constipation associated with FGIDs as determined by the changes in the EOT-SOT score. The study data also highlighted the safety of Bacillus coagulans LBSC at the studied dose. No AEs and/or SAEs were documented during the investigation.

Conclusion

At the studied dose, Bacillus coagulans LBSC was safe for oral consumption and effective in the management of the drug induced constipation associated with FGIDs symptoms.

Global, regional, and national burden of 10 digestive diseases in 204 countries and territories from 1990 to 2019

Background

Digestive diseases are very common worldwide and account for considerable health care use and expenditures. However, there are no global population-based estimates of the disease burden and temporal trend of digestive diseases.

Methods

Annual case numbers, age-standardized rates of prevalence, incidence, death, and disability-adjusted life-years (DALYs), and their estimated annual percentage changes (EAPCs) for digestive diseases between 1990 and 2019 were derived from the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) 2019. The association between digestive disease burden and the sociodemographic index (SDI) was investigated. We also calculated DALYs attributable to risk factors that had evidence of causation with digestive diseases.

Results

Globally, in 2019, there were 88.99 million DALYs due to digestive diseases (3.51% of global DALYs). Digestive diseases were the 13th leading cause of DALYs globally in 2019. Global digestive disease DALYs were highest in the middle SDI quintile and in South Asia and were higher in males than females in 2019. Cirrhosis and other chronic liver diseases constituted the highest proportion of categorized digestive disease DALY burdens globally. From 1990 to 2019, the global age-standardized DALY rate of digestive diseases decreased from 1570.35 in 1990 to 1096.99 in 2019 per 1,00,000 population, with the EAPC being −1.32 (95% confidence interval [CI] −1.36 to −1.27). In 2019, the largest contributor to digestive disease DALYs at the global level, for both sexes, was alcohol use.

Conclusion

The results of this systematic analysis suggest that the global burden of digestive diseases is substantial and varies markedly according to age, sex, SDI, and geographical region. These results provide comprehensive and comparable estimates that can potentially inform efforts toward digestive disease control worldwide.

Comparing Patients Diagnosed With Ineffective Esophageal Motility by the Chicago Classification Version 3.0 and Version 4.0 Criteria

Background

The Chicago Classification version 4.0 (CCv4.0) of ineffective esophageal motility (IEM) is more stringent than the Chicago Classification version 3.0 (CCv3.0) definition. We aimed to compare the clinical and manometric features of patients meeting CCv4.0 IEM criteria (group 1) versus patients meeting CCv3.0 IEM but not CCv4.0 criteria (group 2).

Methods

We collected retrospective clinical, manometric, endoscopic, and radiographic data on 174 adults diagnosed with IEM from 2011 to 2019. Complete bolus clearance was defined as evidence of exit of the bolus by impedance measurement at all distal recording sites. Barium studies included barium swallow, modified barium swallow, and barium upper gastrointestinal series studies, and collected data from these reports include abnormal motility and delay in the passage of liquid barium or barium tablet. These data along with other clinical and manometric data were analyzed using comparison and correlation tests. All records were reviewed for repeated studies and the stability of the manometric diagnoses.

Results

Most demographic and clinical variables were not different between the groups. A lower mean lower esophageal sphincter pressure was correlated with greater percent of ineffective swallows in group 1 (n = 128) (r = -0.2495, P = 0.0050) and not in group 2. In group 1, increased percent of failed contractions on manometry was associated with increased incomplete bolus clearance (r = 0.3689, P = 0.0001). No such association was observed in group 2. A lower median integrated relaxation pressure was correlated with greater percent of ineffective contractions in group 1 (r = -0.1825, P = 0.0407) and not group 2. Symptom of dysphagia was more prevalent (51.6% versus 69.6%, P = 0.0347) in group 2. Dysphagia was not associated with intrabolus pressure, bolus clearance, barium delay, or weak or failed contractions in either group. In the small number of subjects with repeated studies, a CCv4.0 diagnosis appeared more stable over time.

Conclusions

CCv4.0 IEM was associated with worse esophageal function indicated by reduced bolus clearance. Most other features studied did not differ. Symptom presentation cannot predict if patients are likely to have IEM by CCv4.0. Dysphagia was not associated with worse motility, suggesting it may not be primarily dependent on bolus transit.

Perspective: Assessing Tolerance to Nondigestible Carbohydrate Consumption

Human intestinal enzymes do not hydrolyze nondigestible carbohydrates (NDCs), and thus, they are not digested and absorbed in the small intestine. Instead, NDCs are partially to completely fermented by the intestinal microbiota. Select NDCs are associated with health benefits such as laxation and lowering of blood cholesterol and glucose. NDCs provide functional attributes to processed foods, including sugar or fat replacers, thickening agents, and bulking agents. Additionally, NDCs are incorporated into processed foods to increase their fiber content. Although consumption of NDCs can benefit health and contribute functional characteristics to foods, they can cause gastrointestinal symptoms, such as flatulence and bloating. As gastrointestinal symptoms negatively affect consumer well-being and their acceptance of foods containing NDC ingredients, it is crucial to consider tolerance when designing food products and testing their physiological health benefits in clinical trials. This perspective provides recommendations for the approach to assess gastrointestinal tolerance to NDCs, with a focus on study design, population criteria, intervention, comparator, and outcome. Special issues related to studies in children and implications for stakeholders are also discussed. It is recommended that the evaluation of gastrointestinal tolerance to NDCs be conducted in randomized, blinded, controlled crossover studies using standard gastrointestinal questionnaires, with attention to study participant background diets, health status, lifestyle, and medications.

Pathologist's approach to paediatric and neonatal eosinophilic gastrointestinal disorders

Children are not simply miniature adults. The evaluation of their gastrointestinal disorders is therefore different from that in full-grown adults and requires a particular clinical/pathologic approach. Different studies have tried to assess the normal eosinophil distribution in the gastrointestinal tract in adults while very few studies have investigated the paediatric population, consequently complicating the pathologist's ability in identifying an abnormal number of eosinophils in this setting of patients. When evaluating gastrointestinal tract biopsies with eosinophilia, eosinophilic count must be considered along with other histological features like eosinophil distribution in the gastrointestinal wall, their degranulation, cryptitis and crypt abscesses, other accompanying inflammatory cells, apoptotic bodies, foreign material or microorganisms; these findings, although rarely specific, may be a useful aid for diagnosis. Reports should not include a diagnosis of primary eosinophilic gastrointestinal disorders (EoGID) if clinical data and test results do not rule out other forms of gastrointestinal eosinophilia. A more descriptive definition like "with eosinophilic pattern" should be favoured over a specific diagnosis of "eosinophilic disorder" in order to avoid potential confusion between different entities.

Effects of Alkaline-Reduced Water on Gastrointestinal Diseases

Living a healthy lifestyle is the most important need in the world today. However, oxidative stress (OS) is caused by several stress-inducing factors such as smoking, alcohol consumption, chronic diseases, and inflammatory responses, oxygen-free radicals are produced in excess and can damage major organs in the body. This phenomenon has been implicated in the pathogenesis of several gastrointestinal (GI) diseases, including gastritis, constipation, and inflammatory bowel diseases, which include Crohn’s disease, ulcerative colitis, functional dyspepsia, acid reflux, diverticular disease, and irritable bowel syndrome. In this review article, we provide a brief overview of the role of OS in the pathogenesis of GI disorders. Additionally, we discuss the therapeutic role of alkaline-reduced water (ARW) on GI diseases and existing studies on ARW related to GI diseases. Furthermore, we believe that findings from this review article will enhance the knowledge of the readers on the role of ARW on OS and inflammation-based GI diseases.

Specific Changes in the Mammalian Gut Microbiome as a Biomarker for Oxytocin-Induced Behavioral Changes

Prolonged exposure to psychiatric pharmacological agents is often associated with marked gastrointestinal phenomena, including changes in food intake, bowel motility, gastric emptying, and transit time. Those changes are reflected in the gut microbiota composition of the patient and can, therefore, be objectively measured. This is in contrast to the standard psychiatric evaluation of patients, which includes symptoms that are subjectively assessed (i.e., mood, anxiety level, perception, thought disorders, etc.). The association between a drug’s effect on the microbiota and psychiatric symptoms may allow for quantifiable surrogate markers of treatment effectiveness. Changes in the levels of specific drug-sensitive bacterial species can, thus, potentially serve as biomarkers for the intake and effectiveness of psychiatric drugs. Here, we show substantial microbiota changes that were associated with oxytocin administration and the decreased anxiety/depression-like behaviors it conferred in a rat model of corticosterone-induced stress. Compared with oxytocin, citalopram produced more minor effects on the rats’ microbiota. Alterations in the gut microbiota may, therefore, reflect the consumption and effectiveness of some psychiatric drugs.

Fecal S100A12 in Takayasu arteritis predicts disease activity and intestinal involvement

Gastrointestinal involvement in Takayasu Arteritis (TA) requires invasive or expensive diagnostic studies. Instead a fecal biomarker can be used as an initial screening test. In this context, S100A12 is promising as an established biomarker in intestinal inflammation and its role in TA pathogenesis. As such we aimed to test the feasibility of fecal S100A12 as a means of the fecal biomarker in gastrointestinal involvement in TA in this pilot study. Our study population consisted of 30 TA patients and 14 control patients with non-inflammatory arthralgia. Patients with inflammatory or infectious gastrointestinal tract diseases, or used oral antibiotics or NSAIDs for the 3 weeks were excluded. Vasculitis involvements were determined with cross-sectional radiologic studies. TA disease activity was evaluated per Indian Takayasu's Activity Score (2010) criteria and vascular involvements were classified according to Numano classification. ELISA test was used to determine fecal S100A12 levels. Fecal S100A12 levels were higher in TA patients when compared to the controls (37.9 ng/ml vs. 12.5 ng/ml p = 0.038). ESR and CRP levels were also higher in the TA group, however not correlated with fecal S100A12. Among TA patients, fecal S100A12 levels were higher inactive ones with ITAS2010 > 1 (72.9 ng/ml vs. 16.7 ng/ml p = 0.016) correlated with total ITAS2010 scores. (R = 0.52 p = 0.003). TA patients with abdominal symptoms had higher fecal S100A12 levels when compared to the remaining TA population (327.8 ng/ml vs. 28.0 ng/ml p = 0.003). However, fecal S100A12 levels in patients with or without mesenteric vessel involvement did not differ. Fecal S100A12 shows promise as a fecal biomarker to screen intestinal ischemia and inflammatory bowel disease in TA patients.

Stem Cells for Next Level Toxicity Testing in the 21st Century

The call for a paradigm change in toxicology from the United States National Research Council in 2007 initiates awareness for the invention and use of human-relevant alternative methods for toxicological hazard assessment. Simple 2D in vitro systems may serve as first screening tools, however, recent developments infer the need for more complex, multicellular organotypic models, which are superior in mimicking the complexity of human organs. In this review article most critical organs for toxicity assessment, i.e., skin, brain, thyroid system, lung, heart, liver, kidney, and intestine are discussed with regards to their functions in health and disease. Embracing the manifold modes-of-action how xenobiotic compounds can interfere with physiological organ functions and cause toxicity, the need for translation of such multifaceted organ features into the dish seems obvious. Currently used in vitro methods for toxicological applications and ongoing developments not yet arrived in toxicity testing are discussed, especially highlighting the potential of models based on embryonic stem cells and induced pluripotent stem cells of human origin. Finally, the application of innovative technologies like organs-on-a-chip and genome editing point toward a toxicological paradigm change moves into action.

Gastroprotective Effect of Sinapic Acid on Ethanol-Induced Gastric Ulcers in Rats: Involvement of Nrf2/HO-1 and NF-κB Signaling and Antiapoptotic Role

Background: In the current study, we evaluated the therapeutic potential of sinapic acid (SA) in terms of the mechanism underlying its gastroprotective action against ethanol-induced gastric ulcers in rats.

Methods: These effects were examined through gross macroscopic evaluation of the stomach cavity [gastric ulcer index (GUI)], alteration in pH, gastric juice volume, free acidity, total acidity, total gastric wall mucus, and changes in PGE2. In addition, we evaluated lipid peroxidation (malondialdehyde), antioxidant systems (catalase and glutathione), inflammatory markers [tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and myeloperoxidase (MPO)], apoptotic markers (caspase-3, Bax, and Bcl-2), nuclear factor-κB [NF-κB (p65)], NO levels, and histopathological staining (H and E and PAS).

Results: In rats with ethanol-induced ulcers, pre-treatment with SA (40 mg/kg p. o.) decreased the sternness of ethanol-induced gastric mucosal injuries by decreasing the GUI, gastric juice volume, free acidity, and total acidity. In addition, the pH and total gastric mucosa were increased, together with histopathological alteration, neutrophil incursion, and increases in PGE2 and NO₂. These effects were similar to those observed for omeprazole, a standard anti-ulcer drug. SA was shown to suppress gastric inflammation through decreasing TNF-α, IL-6, and MPO, as well as curbing gastric oxidative stress through the inhibition of lipid peroxidation (MDA) and restoration of depleted glutathione and catalase activity. SA inhibited Bcl-2-associated X (Bax) and caspase-3 activity, and restored the antiapoptotic protein Bcl-2; these findings indicate the antiapoptotic potential of SA, leading to enhanced cell survival. SA also repressed NF-κB signaling and increased IκBα. Moreover, SA upregulated the nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), thereby restoring depleted antioxidant defense enzymes and implicating the NRF2/HO-1 signaling pathways.

Conclusion: These results suggest that the prophylactic administration of SA (40 mg/kg) can ameliorate ethanol-induced gastric ulcers in rats primarily via the modulation of Nrf2/HO-1 and NF-κB signaling and subsequent enhancement of cell viability.

Taxonomy, Diversity and Cultivation of the Oudemansielloid/Xeruloid Taxa Hymenopellis, Mucidula, Oudemansiella, and Xerula with Respect to Their Bioactivities: A Review

The oudemansielloid/xeruloid taxa Hymenopellis, Mucidula, Oudemansiella, and Xerula are genera of Basidiomycota that constitute an important resource of bioactive compounds. Numerous studies have shown antimicrobial, anti-oxidative, anti-cancer, anti-inflammatory and other bioactivities of their extracts. The bioactive principles can be divided into two major groups: (a) hydrophilic polysaccharides with relatively high molecular weights and (b) low molecular medium polar secondary metabolites, such as the antifungal strobilurins. In this review, we summarize the state of the art on biodiversity, cultivation of the fungi and bioactivities of their secondary metabolites and discuss future applications. Although the strobilurins are well-documented, with commercial applications as agrochemical fungicides, there are also other known compounds from this group that have not yet been well-studied. Polysaccharides, dihydro-citrinone phenol A acid, scalusamides, and acetylenic lactones such as xerulin, also have potential applications in the nutraceutical, pharmaceutical and medicinal market and should be further explored. Further studies are recommended to isolate high quality bioactive compounds and fully understand their modes of action. Given that only few species of oudemansielloid/xeruloid mushrooms have been explored for their production of secondary metabolites, these taxa represent unexplored sources of potentially useful and novel bioactive metabolites.

Antifungal activity and antidiarrheal activity via antimotility mechanisms of (-)-fenchone in experimental models

BACKGROUND

(-)-Fenchone is a bicyclic monoterpene present in essential oils of plant species, such as Foeniculum vulgare and Peumus boldus, used to treatment of gastrointestinal diseases. Pharmacological studies report its anti-inflammatory, antioxidant, and antinociceptive activity.

AIM

To investigate antidiarrheal activity related to gastrointestinal motility, intestinal secretion and antimicrobial activity.

METHODS

A castor oil-induced diarrhea model was used to evaluate antidiarrheal activity. Intestinal transit and gastric emptying protocols were used to assess a possible antimotility effect. Muscarinic receptors, presynaptic α₂-adrenergic and tissue adrenergic receptors, K_ATP channels, nitric oxide were investigated to uncover antimotility mechanisms of action and castor oil-induced enteropooling to elucidate antisecretory mechanisms. The antimicrobial activity was evaluated in the minimum inhibitory concentration model, the fractional inhibitory concentration index using the (-)-fenchone association method with standard antifungal agents.

RESULTS

(-)-Fenchone (75, 150 and 300 mg/kg) showed antidiarrheal activity, with a significant decrease in the evacuation index. This activity is possibly related to a percentage of reduced intestinal transit (75, 150 and 300 mg/kg). The antimotility effect of (-)-fenchone decreased in the presence of pilocarpine, yohimbine, propranolol, L-NG-nitroarginine methyl ester or glibenclamide. In the enteropooling model, no reduction in intestinal fluid weight was observed. (-)- Fenchone did not show antibacterial activity; on the other hand, inhibits the growth of strains of fungi with a minimum fungicide concentration of 32 μg/mL. However, when it was associated with amphotericin B, no synergism was observed.

CONCLUSION

The antidiarrheal effect of (-)-fenchone in this study involves antimotility effect and not involve antisecretory mechanisms. (-)-Fenchone presents antifungal activity; however, it did not show antibacterial activity.

Intestinal permeation enhancers to improve oral bioavailability of macromolecules: reasons for low efficacy in humans

INTRODUCTION

Intestinal permeation enhancers (PEs) are substances that transiently alter the intestinal epithelial barrier to facilitate permeation of macromolecules with low oral bioavailability (BA). While a number of PEs have progressed to clinical testing in conventional formulations with macromolecules, there has been only low single digit increases in oral BA, irrespective of whether the drug met primary or secondary clinical endpoints.

AREAS COVERED

This article considers the causes of sub-optimal BA of macromolecules from PE dosage forms and suggests approaches that may improve performance in humans.

EXPERT OPINION

Permeation enhancement is most effective when the PE is co-localized with the macromolecule at the epithelial surface. Conditions in the GI tract impede optimal co-localization. Novel delivery systems that limit dilution and spreading of the PE and macromolecule in the small intestine have attempted to replicate promising enhancement efficacy observed in static drug delivery models.

Gastrointestinal Disorders and Metabolic Syndrome: Dysbiosis as a Key Link and Common Bioactive Dietary Components Useful for their Treatment

Gastrointestinal (GI) diseases, which include gastrointestinal reflux disease, gastric ulceration, inflammatory bowel disease, and other functional GI disorders, have become prevalent in a large part of the world population. Metabolic syndrome (MS) is cluster of disorders including obesity, hyperglycemia, hyperlipidemia, and hypertension, and is associated with high rate of morbidity and mortality. Gut dysbiosis is one of the contributing factors to the pathogenesis of both GI disorder and MS, and restoration of normal flora can provide a potential protective approach in both these conditions. Bioactive dietary components are known to play a significant role in the maintenance of health and wellness, as they have the potential to modify risk factors for a large number of serious disorders. Different classes of functional dietary components, such as dietary fibers, probiotics, prebiotics, polyunsaturated fatty acids, polyphenols, and spices, possess positive impacts on human health and can be useful as alternative treatments for GI disorders and metabolic dysregulation, as they can modify the risk factors associated with these pathologies. Their regular intake in sufficient amounts also aids in the restoration of normal intestinal flora, resulting in positive regulation of insulin signaling, metabolic pathways and immune responses, and reduction of low-grade chronic inflammation. This review is designed to focus on the health benefits of bioactive dietary components, with the aim of preventing the development or halting the progression of GI disorders and MS through an improvement of the most important risk factors including gut dysbiosis.

Paroxetine Administration Affects Microbiota and Bile Acid Levels in Mice

Recent interest in the role of microbiota in health and disease has implicated gut microbiota dysbiosis in psychiatric disorders including major depressive disorder. Several antidepressant drugs that belong to the class of selective serotonin reuptake inhibitors have been found to display antimicrobial activities. In fact, one of the first antidepressants discovered serendipitously in the 1950s, the monoamine-oxidase inhibitor Iproniazid, was a drug used for the treatment of tuberculosis. In the current study we chronically treated DBA/2J mice for 2 weeks with paroxetine, a selective serotonin reuptake inhibitor, and collected fecal pellets as a proxy for the gut microbiota from the animals after 7 and 14 days. Behavioral testing with the forced swim test revealed significant differences between paroxetine- and vehicle-treated mice. Untargeted mass spectrometry and 16S rRNA profiling of fecal pellet extracts showed several primary and secondary bile acid level, and microbiota alpha diversity differences, respectively between paroxetine- and vehicle-treated mice, suggesting that microbiota functions are altered by the drug. In addition to their lipid absorbing activities bile acids have important signaling activities and have been associated with gastrointestinal diseases and colorectal cancer. Antidepressant drugs like paroxetine should therefore be used with caution to prevent undesirable side effects.

Drug-Induced Small Bowel Injury: a Challenging and Often Forgotten Clinical Condition

PURPOSE OF REVIEW

Most drugs are given by the oral route. Oral intake allows direct contact between the drug and the entire GI tract mucosa, exposing it to potential topical damage until absorption. Medication-induced GI symptoms and lesions are therefore commonly encountered in clinical practice. This review will examine the most common drugs or classes of drugs affecting small bowel function and/or structure.

RECENT FINDINGS

Since non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used medicines, NSAID enteropathy is highly prevalent and brings about considerable morbidity. Antimicrobials and proton-pump inhibitors profoundly modify intestinal microbiota, affecting gut sensory and motor functions, while other drugs (like iron and gold derivatives) impair intestinal permeability. Olmesartan (and likely ACE inhibitors) induce villous atrophy and consequent malabsorption. Mycophenolate mofetil, cancer chemotherapeutic agents, and immune checkpoint inhibitors cause intestinal inflammation, abdominal pain, and diarrhea. Potassium chloride supplements may induce small bowel ulceration, stenosis, and perforation while the cotraceptive pill and anticoagulants are associated with intestinal ischemia and spontaneous intramural hematoma, respectively. In clinical practice, a deep knowledge of clinical pharmacology and toxicology and a high degree of suspicion of drug-related adverse events are mandatory. Only then, the practicing physician will be able to diagnose medication-induced small bowel lesions correctly and will implement the best strategies to treat them.

Dysphagia: Thinking outside the box

Dysphagia is a common symptom that is important to recognise and appropriately manage, given that causes include life threatening oesophageal neoplasia, oropharyngeal dysfunction, the risk of aspiration, as well as chronic disabling gastroesophageal reflux (GORD). The predominant causes of dysphagia varies between cohorts depending on the interplay between genetic predisposition and environmental risk factors, and is changing with time. Currently in white Caucasian societies adopting a western lifestyle, obesity is common and thus associated gastroesophageal reflux disease is increasingly diagnosed. Similarly, food allergies are increasing in the west, and eosinophilic oesophagitis is increasingly found as a cause. Other regions where cigarette smoking is still prevalent, or where access to medical care and antisecretory agents such as proton pump inhibitors are less available, benign oesophageal peptic strictures, Barrett's oesophagus, adeno- as well as squamous cell carcinoma are endemic. The evaluation should consider the severity of symptoms, as well as the pre-test probability of a given condition. In young white Caucasian males who are atopic or describe heartburn, eosinophilic esophagitis and gastroesophageal reflux disease will predominate and a proton pump inhibitor could be commenced prior to further investigation. Upper gastrointestinal endoscopy remains a valid first line investigation for patients with suspected oesophageal dysphagia. Barium swallow is particularly useful for oropharyngeal dysphagia, and oesophageal manometry mandatory to diagnose motility disorders.

Unusual case of immune-related colitis

The cancer immunotherapy field has had many promising developments in recent years. Checkpoint inhibitors are good examples of that. This new class of medications comes with a new constellation of side effects that require early recognition and management. Here we present a patient with metastatic adenocarcinoma on pembrolizumab who was admitted to the hospital for colitis. This was found to be an immune-related adverse event from pembrolizumab. We discuss our work-up and approach to the diagnosis, then highlight important treatment pearls for internal medicine physicians who are increasingly taking care of such patients.

Maytenus erythroxylon Reissek (Celastraceae) ethanol extract presents antidiarrheal activity via antimotility and antisecretory mechanisms

AIM

To investigate the acute toxicity, phytochemical profile, antidiarrheal activity and mechanisms of action of Maytenus erythroxylon (M. erythroxylon) ethanol extract.

METHODS

A castor oil-induced diarrhea model was used to evaluate antidiarrheal activity. Intestinal transit and gastric emptying protocols were used to evaluate a possible antimotility effect. K_ATP channels, nitric oxide, presynaptic α2-adrenergic and tissue adrenergic receptors were investigated to uncover antimotility mechanisms of action and castor oil-induced enteropooling to elucidate antisecretory mechanisms.

RESULTS

All tested doses of the extract (62.5, 125, 250 and 500 mg/kg) possessed antidiarrheal activity, with a significant decrease of the evacuation index. This activity is possibly related to a reduced gastric emptying (125, 250 and 500 mg/kg) and to a decreased percentage of intestinal transit for all tested doses. That last effect seems to be modulated by nitric oxide, K_ATP channels and tissue adrenergic receptors. Besides, the extract also presented antisecretory effect due to a decrease of intestinal fluid accumulation.

CONCLUSION

The antidiarrheal effect of M. erythroxylon found in this study involves antimotility and antisecretory mechanisms that may be attributed to the chemical compounds found in this species: saponins, flavonoids, tannins, triterpenes and steroids.

Spectrum of Drug-induced Chronic Diarrhea

The evaluation of a patient with chronic diarrhea can be quite frustrating, as it is expensive and involves multiple diagnostic studies. Moreover, identification of a drug as a cause of chronic diarrhea is a challenge in patients taking multiple medications. The disease may either be associated with intestinal mucosal changes, mimicking diseases such as celiac disease, or purely functional, with no histopathologic change. Drug-induced diarrhea may or may not be associated with malabsorption of nutrients, and a clinical improvement may occur within days of discontinuation of the drug, or may take longer when associated with mucosal injury. Diarrhea in diabetics, often attributed to poor management and lack of control, may be due to oral hypoglycaemic agents. Chemotherapy can result in diffuse or segmental colitis, whereas olmesartan and a few other medications infrequently induce a disease that mimics celiac disease, but is not associated with gluten intolerance. In short, increased awareness of a drug, as a cause for diarrhea and a clear understanding of the clinical manifestations will help clinicians to solve this challenging problem. This article aims to review drug-induced diarrhea to (a) understand known pathophysiological mechanisms; (b) assess the risk associated with frequently prescribed medications, and discuss the pathogenesis; and

Primer for nutritionists: Managing the side effects of antidepressants

Depression is a chronic disease affecting a significant portion of the U.S.

POPULATION

Due to the popularity of ADs most nutrition professionals working in the outpatient setting will encounter patients taking one of these medications. Nutritionist can assist patients in managing the short and long term side effects of ADs and, taking into account other nutritional issues, improve overall wellbeing of the patient. The objective of this paper is to identify what side effects nutritionists can help manage, provide the information necessary to help nutritionists feel comfortable assisting with that management, and, as a result, play a valuable role in the team that is vested in the health and wellbeing of the patient.

Analgesic drugs and the gut - a reciprocal relationship

Analgesic drugs, as well as providing pain relief, can cause a range of other symptoms and side effects, most notably on the gastrointestinal system. Conversely, gastrointestinal disease will often require analgesia, and this can be complicated by the fact that the gut is the site of absorption of oral drugs. This paper discusses some of the effects of common oral analgesic drugs on the gastrointestinal tract and their role in managing some of the most common, nonmalignant, chronic gastrointestinal disorders in adults.

Influence of environmental factors in the development of inflammatory bowel diseases

Idiopathic inflammatory bowel diseases (IBD), Crohn's disease (CD) and ulcerative colitis (UC), are multifactorial diseases that are manifested after disruption of a genetic predisposed individual and its intestinal microflora through an environmental stimulus. Urbanization and industrialization are associated with IBD. Epidemiological data, clinical observations and family/immigrants studies indicate the significance of environmental influence in the development of IBD. Some environmental factors have a different effect on the subtypes of IBD. Smoking and appendectomy is negatively associated with UC, but they are aggravating factors for CD. A westernized high fat diet, full of refined carbohydrates is strongly associated with the development of IBD, contrary to a high in fruit, vegetables and polyunsaturated fatty acid-3 diet that is protective against these diseases. High intake of nonsteroidal antiinflammatory drug and oral contraceptive pills as well as the inadequacy of vitamin D leads to an increased risk for IBD and a more malignant course of disease. Moreover, other factors such as air pollution, psychological factors, sleep disturbances and exercise influence the development and the course of IBD. Epigenetic mechanism like DNA methylation, histone modification and altered expression of miRNAS could explain the connection between genes and environmental factors in triggering the development of IBD.