Inaccuracy of patient-reported descriptions of and satisfaction with bowel actions in irritable bowel syndrome.

BACKGROUND: Perception of diarrhea and constipation differs greatly. This study aimed to correlate subjective and objective assessment of fecal characteristics in irritable bowel syndrome (IBS) patients. METHODS: Data from two interventional dietary trials with varying FODMAP (Fermentable Oligosaccharides, Disaccharides, Monosaccharides And Polyols) or gluten content were interrogated. Subjects rated their dissatisfaction with stool consistency daily using a visual analog scale during the interventions. Subjects collected stools at the end of each intervention. Each stool was scored according to the King's Stool Chart (KSC). Fecal water content (FWC) was measured on pooled feces by freeze drying, with diarrhea defined as ≥78%. KEY RESULTS: Seventy IBS (Rome III) and eight healthy subjects were studied. Each subject's self-rating of stool consistency during the most symptomatic diet was approximately double that of their least. Degree of dissatisfaction with stool consistency correlated poorly with changes in FWC and KSC. IBS subtype related poorly to objective measures of stool consistency. Sixty percent of IBS-D subjects had diarrhea on objective measures. Eighty-five percent with IBS-C had hard and formed stools but three patients met the criteria for diarrhea. One healthy subject had diarrhea on FWC and KSC, and six had hard, formed stools. No differences in FWC was observed when subjects consumed differing amounts of FODMAPs or gluten (all P > .200). CONCLUSIONS AND INFERENCES: There are major disparities between patients' stool descriptions and objective features of constipation and diarrhea. Patient-reported bowel habits require more interrogation for accurate IBS subtyping. Varying FODMAP or gluten content of the diet is not associated with consistent change in FWC.

Appropriate clinical use of human leukocyte antigen typing for coeliac disease: an Australasian perspective.

The past decade has seen human leukocyte antigen (HLA) typing emerge as a remarkably popular test for the diagnostic work-up of coeliac disease with high patient acceptance. Although limited in its positive predictive value for coeliac disease, the strong disease association with specific HLA genes imparts exceptional negative predictive value to HLA typing, enabling a negative result to exclude coeliac disease confidently. In response to mounting evidence that the clinical use and interpretation of HLA typing often deviates from best practice, this article outlines an evidence-based approach to guide clinically appropriate use of HLA typing, and establishes a reporting template for pathology providers to improve communication of results.

Cognitive impairment in coeliac disease improves on a gluten-free diet and correlates with histological and serological indices of disease severity.

BACKGROUND: Mild impairments of cognition or 'Brain fog' are often reported by patients with coeliac disease but the nature of these impairments has not been systematically investigated. AIM: This longitudinal pilot study investigated relationships between cognitive function and mucosal healing in people with newly diagnosed coeliac disease commencing a gluten-free diet. METHODS: Eleven patients (8 females, 3 males), mean age 30 (range 22-39) years, were tested with a battery of cognitive tests at weeks 0, 12 and 52. Information processing efficacy, memory, visuospatial ability, motoric function and attention were tested. Small bowel biopsies were collected via routine gastroscopy at weeks 12 and 52 and were compared to baseline Marsh scores. Cognitive performance was compared to serum concentrations of tissue transglutaminase antibodies, biopsy outcomes and other biological markers. RESULTS: All patients had excellent adherence to the diet. Marsh scores improved significantly (P = 0.001, Friedman's test) and tissue transglutaminase antibody concentrations decreased from a mean of 58.4 at baseline to 16.8 U/mL at week 52 (P = 0.025). Four of the cognitive tests assessing verbal fluency, attention and motoric function showed significant improvement over the 12 months and strongly correlated with the Marsh scores and tissue transglutaminase antibody levels (r = 0.377-0.735; all P < 0.05). However, no meaningful patterns of correlations were found for nutritional or biochemical markers, or markers of intestinal permeability. CONCLUSIONS: In newly diagnosed coeliac disease, cognitive performance improves with adherence to the gluten-free diet in parallel to mucosal healing. Suboptimal levels of cognition in untreated coeliac disease may affect the performance of everyday tasks.