Association between irritable bowel syndrome and micronutrients: A systematic review.

BACKGROUND AND AIM: Irritable bowel syndrome (IBS) is a highly prevalent disorder of gut brain interaction with a multifactorial etiology. Food trigger avoidance is common among individuals with IBS and exclusion diets are gaining popularity. However, recent guidelines on IBS management cautioned regarding the use of unsupervised dietary therapy with concerns of development of poor eating habits and even nutritional deficiencies. We aimed to review the available literature on the effect of habitual and exclusion diets on micronutrient status as well as the role of micronutrient supplementation in alleviating IBS symptoms. METHODS: Four electronic databases (PubMed, Embase, Cochrane, Web of Science) were searched for articles that reported micronutrient data in patients with IBS. Serum micronutrient levels and dietary intake of micronutrients in patients with IBS were collected. The extracted data were tabulated and organized by micronutrient type to observe for trends. RESULTS: Twenty-six articles were included in this systematic review (12 interventional and 14 observational studies). Studies showed that generally IBS subjects had lower levels of vitamin B2, vitamin D, calcium, and iron at baseline compared with non-IBS subjects. Studies also found that exclusion diets were associated with lower intake of micronutrients especially vitamin B1, B2, calcium, iron, and zinc. There was a lack of interventional studies on micronutrients. CONCLUSION: Irritable bowel syndrome patients are at risk of developing multiple micronutrient deficiencies that may have both localized gastrointestinal as well as systemic effects. Dietary management of IBS patients should include a proper dietitian review to ensure nutritional adequacy where possible.

Review of the role of gastrointestinal multiplex polymerase chain reaction in the management of diarrheal illness.

Acute and chronic diarrheal illness secondary to gastrointestinal infection is a significant cause of morbidity and mortality around the world. A cornerstone of management includes prompt diagnosis and appropriate treatment of culprit pathogens. Timely diagnosis can improve patient care, assist in infection control, and prevent disease outbreaks. Historical methods of diagnosis include traditional culture methods and stool analysis. These are limited by long turnaround time and inability to simultaneously assess multiple pathogens. The advent of multiplexed nucleic acid amplification tests first began with the Food and Drug Administration-approved respiratory virus multiplex polymerase chain reaction (PCR) panel in 2009, followed by gastrointestinal infections in 2013, and neurological infections in 2014. We conducted a review of current literature pertaining to the clinical utility of a gastrointestinal multiplex PCR in management of acute and chronic diarrhea in patients. To date, seven platforms approved by the US Food and Drug Administration are used in detection of various bacterial, viral, and parasitic causative organisms for diagnosis of gastrointestinal infections. The sensitivity and specificity of each assay vary depending on the tested organism. Interpretation of a positive result has to be tailored to the clinical context. Further studies are required to establish the utility of gastrointestinal multiplex PCR from a cost-based perspective, whether specific enteropathogens such as Clostridioides difficile are better assessed with toxin gene detection and whether new parameters such as cycle threshold values can improve clinical application of test results.

Correlation of functional impairment and morphological alterations in patients with group 2A idiopathic juxtafoveal retinal telangiectasia.

OBJECTIVE: To correlate functional impairment with morphological alterations in patients with group 2A idiopathic juxtafoveal retinal telangiectasia. METHODS: As part of the Macular Telangiectasia Project, a cohort of 10 patients underwent additional functional testing and imaging studies including photopic and scotopic fine matrix mapping, microperimetry, reflectance, and autofluorescence imaging with scanning laser ophthalmoscopy. RESULTS: From clinical stage 2 to 5, scotopic central function was reduced, which corresponded to depletion of macular pigment density. From clinical stage 3 onward, severe photopic and scotopic scotomata with up to 30 dB of loss were found next to fixation and were not totally confined to abnormalities seen with standard imaging modalities. The number of test points with loss of 10 dB or more was significantly greater for scotopic testing than for photopic testing (P = .007, Wilcoxon signed rank test). CONCLUSIONS: Rod function may be more severely affected than cone function in patients with group 2A idiopathic juxtafoveal retinal telangiectasia, and this may occur early in the disease progression. Severe reduction in retinal sensitivity is spatially confined to morphological alterations seen with scanning laser ophthalmoscopy imaging. The findings imply that idiopathic juxtafoveal retinal telangiectasia is not solely a vascular disease and that early neuronal involvement may be implicated in the pathogenesis of the disease.