Healthcare utilisation of patients with cholecystolithiasis in primary care: a multipractice comparative analysis.

OBJECTIVES: To examine general practitioners' (GP) management of cholecystolithiasis and to evaluate persisting abdominal complaints in the years after the diagnosis. DESIGN: Retrospective analysis of registry data and a subset of individual medical records. SETTING: Seventeen primary care practices affiliated with the Radboudumc Practice Based Research Network in the Netherlands. PARTICIPANTS: 633 patients with cholecystolithiasis diagnosed between 2012 and 2016. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome of this study was the healthcare utilisation of patients with cholecystolithiasis diagnosed by the GP in terms of referrals to secondary care, laboratory diagnostics, prescribed medication and the prevalence of concomitant abdominal-related diagnoses in a time interval of 3 years before and 3 years after diagnosis of cholecystolithiasis. For secondary outcomes, electronic medical records were studied from seven practices to assess emergency department visits, operation rates and repeat visits for persistent abdominal symptoms. We compared the non-referred group with the referred group. RESULTS: In 57% of patients, concomitant abdominal-related diagnoses were recorded besides the diagnosis cholecystolithiasis. In-depth analyses of 294 patients showed a referral rate of 79.3% (n=233); 62.9% (n=185) underwent cholecystectomy. After referral, 55.4% (129/233) returned to the GP for persistent abdominal symptoms. Patients returning after referral were more often treated for another abdominal-related diagnosis before cholecystolithiasis was recorded (51.9% vs 28.8%, p<0.001). CONCLUSIONS: The majority of patients in general practice with gallstones are referred and undergo cholecystectomy. Patients with concomitant abdominal-related diagnoses are likely to return to their physician. GPs should inform patients about these outcomes to improve the shared decision-making process before gallbladder surgery.

Protease signaling through protease activated receptor 1 mediate nerve activation by mucosal supernatants from irritable bowel syndrome but not from ulcerative colitis patients.

BACKGROUND & AIMS: The causes of gastrointestinal complaints in irritable bowel syndrome (IBS) remain poorly understood. Altered nerve function has emerged as an important pathogenic factor as IBS mucosal biopsy supernatants consistently activate enteric and sensory neurons. We investigated the neurally active molecular components of such supernatants from patients with IBS and quiescent ulcerative colitis (UC). METHOD: Effects of supernatants from 7 healthy controls (HC), 20 IBS and 12 UC patients on human and guinea pig submucous neurons were studied with neuroimaging techniques. We identify differentially expressed proteins with proteome analysis. RESULTS: Nerve activation by IBS supernatants was prevented by the protease activated receptor 1 (PAR1) antagonist SCHE79797. UC supernatants also activated enteric neurons through protease dependent mechanisms but without PAR1 involvement. Proteome analysis of the supernatants identified 204 proteins, among them 17 proteases as differentially expressed between IBS, UC and HC. Of those the four proteases elastase 3a, chymotrypsin C, proteasome subunit type beta-2 and an unspecified isoform of complement C3 were significantly more abundant in IBS compared to HC and UC supernatants. Of eight proteases, which were upregulated in IBS, the combination of elastase 3a, cathepsin L and proteasome alpha subunit-4 showed the highest prediction accuracy of 98% to discriminate between IBS and HC groups. Elastase synergistically potentiated the effects of histamine and serotonin-the two other main neuroactive substances in the IBS supernatants. A serine protease inhibitor isolated from the probiotic Bifidobacterium longum NCC2705 (SERPINBL), known to inhibit elastase-like proteases, prevented nerve activation by IBS supernatants. CONCLUSION: Proteases in IBS and UC supernatants were responsible for nerve activation. Our data demonstrate that proteases, particularly those signalling through neuronal PAR1, are biomarker candidates for IBS, and protease profiling may be used to characterise IBS.

Neuronal activation by mucosal biopsy supernatants from irritable bowel syndrome patients is linked to visceral sensitivity.

Based on the discomfort/pain threshold during rectal distension, irritable bowel syndrome (IBS) patients may be subtyped as normo- or hypersensitive. We previously showed that mucosal biopsy supernatants from IBS patients activated enteric and visceral afferent neurons. We tested the hypothesis that visceral sensitivity is linked to the degree of neuronal activation. Normo- and hypersensitive IBS patients were distinguished by their discomfort/pain threshold to rectal balloon distension with a barostat. Using potentiometric and Ca(2+) dye imaging, we recorded the response of guinea-pig enteric submucous and mouse dorsal root ganglion (DRG) neurons, respectively, to mucosal biopsy supernatants from normosensitive (n = 12 tested in enteric neurons, n = 9 tested in DRG) and hypersensitive IBS patients (n = 9, tested in both types of neurons). In addition, we analysed the association between neuronal activation and individual discomfort/pain pressure thresholds. The IBS supernatants evoked Ca(2+) transients in DRG neurons and spike discharge in submucous neurons. Submucous and DRG neurons showed significantly stronger responses to supernatants from hypersensitive IBS patients as reflected by higher spike frequency or stronger [Ca(2+)]i transients in a larger proportion of neurons. The neuroindex as a product of spike frequency or [Ca(2+)]i transients and proportion of responding neurons correlated significantly with the individual discomfort/pain thresholds of the IBS patients. Supernatants from hypersensitive IBS patients caused stronger activation of enteric and DRG neurons. The level of activation correlated with the individual discomfort/pain threshold pressure values. These findings support our hypothesis that visceral sensitivity is linked to activation of peripheral neurons by biopsy supernatants.

Mucosal immune cell numbers and visceral sensitivity in patients with irritable bowel syndrome: is there any relationship?

OBJECTIVES: Repeated exposure to stress leads to mast cell degranulation, microscopic inflammation, and subsequent visceral hypersensitivity in animal models. To what extent this pathophysiological pathway has a role in patients with the irritable bowel syndrome (IBS) has not been properly investigated. The objective of this study was to assess the relationship between visceral hypersensitivity, microscopic inflammation, and the stress response in IBS. METHODS: Microscopic inflammation of the colonic mucosa was evaluated by immunohistochemistry in 66 IBS patients and 20 healthy volunteers (HV). Rectal sensitivity was assessed by a barostat study using an intermittent pressure-controlled distension protocol. Salivary cortisol to a psychological stress was measured to assess the stress response. RESULTS: Compared with HV, mast cells, T cells, and macrophages were decreased in IBS patients. Similarly, λ-free light chain (FLC)-positive mast cells were decreased but not immunoglobulin E (IgE)- and IgG-positive mast cells. There were no differences between hypersensitive and normosensitive IBS patients. No relation was found between any of the immune cells studied and the thresholds of discomfort, urge, first sensation, or IBS symptoms (e.g., abdominal pain, stool-related complaints, bloating). Finally, stress-related symptoms and the hypothalamic-pituitary-adrenal-axis response to stress were not correlated with the number of mast cells or the presence of visceral hypersensitivity. CONCLUSIONS: Although the number of mast cells, macrophages, T cells, and λFLC-positive mast cells is decreased in IBS compared with HV, this is not associated with the presence of visceral hypersensitivity or abnormal stress response. Our data question the role of microscopic inflammation as an underlying mechanism of visceral hypersensitivity, but rather suggest dysregulation of the mucosal immune system in IBS.

The dopaminergic system in patients with functional dyspepsia analysed by single photon emission computed tomography (SPECT) and an alpha-methyl-para-tyrosine (AMPT) challenge test.

PURPOSE: Functional dyspepsia (FD) is a chronic condition characterized by upper abdominal symptoms without an identifiable cause. While the serotonergic system is thought to play a key role in the regulation of gut physiology, the role of the dopaminergic system, which is important in the regulation of visceral pain and stress, is under-studied. Therefore, this study investigated the dopaminergic system and its relationship with drinking capacity and symptoms in FD patients. METHODS: In FD patients and healthy volunteers (HV) the dopaminergic system was investigated by in-vivo assessment of central dopamine D2 receptors (D2Rs) with [(123)I]IBZM SPECT and by an acute, but reversible, dopamine depletion alpha-methyl-para-tyrosine (AMPT) challenge test. A nutrient drink test was performed to investigate the association between maximal ingested volume, evoked symptoms, and D2Rs. RESULTS: The HV subjects comprised 12 women and 8 men (mean age 31 ± 3 years), and the FD patients comprised 5 women and 3 men (mean age 39 ± 5 years). The FD patients had a lower left plus right average striatal binding potential (BP(NP)) for the caudate nucleus (p = 0.02), but not for putamen (p = 0.15), which in the FD patients was correlated with maximal ingested volume (r = 0.756, p = 0.03). The D2R BP(NP) in the putamen was correlated with nausea (r = 0.857, p = 0.01). The acute dopamine depletion test, however, failed to reveal differences in prolactin release between the FD patients and the HV subjects. CONCLUSION: These preliminary data suggest that chronic rather than acute alterations in the dopaminergic system may be involved in the pathogenesis of FD. Further studies are required to reproduce our novel findings and to evaluate to what extent the dopaminergic changes may be secondary to abnormalities in serotonergic pathways.

Lower striatal dopamine D2/3 receptor availability in obese compared with non-obese subjects.

BACKGROUND: Obesity is a result of a relative excess in energy intake over energy expenditure. These processes are controlled by genetic, environmental, psychological and biological factors. One of the factors involved in the regulation of food intake and satiety is dopaminergic signalling. A small number of studies have reported that striatal dopamine D2/D3 receptor [D2/3R] availability is lower in morbidly obese subjects. METHODS: To confirm the role of D2/3R in obesity, we measured striatal D2/3R availability, using [123I]IBZM SPECT, in 15 obese women and 15 non-obese controls. RESULTS: Striatal D2/3R availability was 23% (p = 0.028) lower in obese compared with non-obese women. CONCLUSION: This study is an independent replication of the finding that severely obese subjects have lower striatal D2/3R availability. Our findings invigorate the evidence for lower striatal D2/3R availability in obesity and confirm the role of the striatal dopaminergic reward system in obesity.

The mast cell stabiliser ketotifen decreases visceral hypersensitivity and improves intestinal symptoms in patients with irritable bowel syndrome.

BACKGROUND: Mast cell activation is thought to be involved in visceral hypersensitivity, one of the main characteristics of the irritable bowel syndrome (IBS). A study was therefore undertaken to investigate the effect of the mast cell stabiliser ketotifen on rectal sensitivity and symptoms in patients with IBS. METHODS: 60 patients with IBS underwent a barostat study to assess rectal sensitivity before and after 8 weeks of treatment. After the initial barostat, patients were randomised to receive ketotifen or placebo. IBS symptoms and health-related quality of life were scored. In addition, mast cells were quantified and spontaneous release of tryptase and histamine was determined in rectal biopsies and compared with biopsies from 22 age- and gender-matched healthy volunteers. RESULTS: Ketotifen but not placebo increased the threshold for discomfort in patients with IBS with visceral hypersensitivity. This effect was not observed in normosensitive patients with IBS. Ketotifen significantly decreased abdominal pain and other IBS symptoms and improved quality of life. The number of mast cells in rectal biopsies and spontaneous release of tryptase were lower in patients with IBS than in healthy volunteers. Spontaneous release of histamine was mostly undetectable but was slightly increased in patients with IBS compared with healthy volunteers. Histamine and tryptase release were not altered by ketotifen. CONCLUSIONS: This study shows that ketotifen increases the threshold for discomfort in patients with IBS with visceral hypersensitivity, reduces IBS symptoms and improves health-related quality of life. Whether this effect is secondary to the mast cell stabilising properties of ketotifen or H(1) receptor antagonism remains to be further investigated. Trial Registration Number NTR39, ISRCTN22504486.

Exposure to severe wartime conditions in early life is associated with an increased risk of irritable bowel syndrome: a population-based cohort study.

OBJECTIVES: Stressful events during early life have been suggested to play an important role in the development of the irritable bowel syndrome (IBS). In this study, we evaluate whether an exposure to severe wartime conditions during gestation and in early life are associated with an increased prevalence of IBS. METHODS: We assessed the prevalence of IBS using the Rome II questionnaire among 816 men and women (aged 58+/-1 years) who were born as term singletons in Wilhelmina Gasthuis, Amsterdam, The Netherlands around the time of World War II. RESULTS: Of a total of 816 participants, 9.6% (n=78, 52F) met the criteria for IBS. Exposure to severe wartime conditions in utero was not associated with the prevalence of IBS in adulthood (8.3%). Early-life exposure to severe wartime conditions was associated with an increased prevalence of IBS. The prevalence of IBS among individuals exposed up to 0.5 years of age, 1 year of age, and 1.5 years of age was 8.1%, 12.5%, and 15.3%, respectively. The increased IBS prevalence was not associated with an increased stress response. CONCLUSIONS: Our data indicate that exposure to severe wartime conditions in early life is associated with an increased risk of developing IBS. To what extent this is attributable to the stressful environment of war, to severe undernutrition, or to the increased prevalence of infectious diseases is, however, unclear.