The DTC microbiome testing industry needs more regulation.

Tests lack analytical and clinical validity, requiring more federal oversight to prevent consumer harm.

ExpLOring the role of the intestinal MiCrobiome in InflammATory bowel disease-AssocIated SpONdylarthritis (LOCATION-IBD).

Background: Inflammatory Bowel Disease (IBD)-associated arthritis is a frequent and potentially debilitating complication of IBD, that can affect those with or without active intestinal disease, and is often difficult to treat. The microbiome is known to play a role in IBD development and has been shown to be associated with inflammatory arthritis without concomitant IBD, but its role in IBD-associated arthritis is still unexplored. Further, disease localization is associated with development of IBD-associated arthritis, and stool compositional profiles are predictive of disease localization, yet mucosal location-specific microbiomes have not been well characterized. To address this gap in understanding, we designed a study (LOCATION-IBD) to characterize the mucosa-associated intestinal microbiome and metabolome in IBD-associated arthritis. Methods: Adults with an established diagnosis of IBD undergoing clinical colonoscopy between May of 2021 and February of 2023 were invited to participate in this study; those interested in participation who met inclusion criteria were enrolled. Prior to enrollment, participants were stratified into those with or without IBD-associated arthritis. All participants were interviewed and had clinical and demographic data collected, and 97.8% completed clinical colonoscopy with biopsy collection. Results and conclusion: A total of 182 participants, 53 with confirmed IBD-associated arthritis, were enrolled in this study, resulting in 1151 biopsies obtained for microbiome and metabolome analysis (median 6, mean 6.3 per participant). Clinical and demographic data obtained from the study population will be analyzed with microbiome and metabolome data obtained from biopsies, with the goal of better understanding the mechanisms underpinning the host-microbiome relationship associated the development of IBD-associated arthritis.

Baseline Features and Reasons for Nonparticipation in the Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) Study, a Colorectal Cancer Screening Trial.

Importance: The Colonoscopy Versus Fecal Immunochemical Test in Reducing Mortality From Colorectal Cancer (CONFIRM) randomized clinical trial sought to recruit 50 000 adults into a study comparing colorectal cancer (CRC) mortality outcomes after randomization to either an annual fecal immunochemical test (FIT) or colonoscopy. Objective: To (1) describe study participant characteristics and (2) examine who declined participation because of a preference for colonoscopy or stool testing (ie, fecal occult blood test [FOBT]/FIT) and assess that preference's association with geographic and temporal factors. Design, Setting, and Participants: This cross-sectional study within CONFIRM, which completed enrollment through 46 Department of Veterans Affairs medical centers between May 22, 2012, and December 1, 2017, with follow-up planned through 2028, comprised veterans aged 50 to 75 years with an average CRC risk and due for screening. Data were analyzed between March 7 and December 5, 2022. Exposure: Case report forms were used to capture enrolled participant data and reasons for declining participation among otherwise eligible individuals. Main Outcomes and Measures: Descriptive statistics were used to characterize the cohort overall and by intervention. Among individuals declining participation, logistic regression was used to compare preference for FOBT/FIT or colonoscopy by recruitment region and year. Results: A total of 50 126 participants were recruited (mean [SD] age, 59.1 [6.9] years; 46 618 [93.0%] male and 3508 [7.0%] female). The cohort was racially and ethnically diverse, with 748 (1.5%) identifying as Asian, 12 021 (24.0%) as Black, 415 (0.8%) as Native American or Alaska Native, 34 629 (69.1%) as White, and 1877 (3.7%) as other race, including multiracial; and 5734 (11.4%) as having Hispanic ethnicity. Of the 11 109 eligible individuals who declined participation (18.0%), 4824 (43.4%) declined due to a stated preference for a specific screening test, with FOBT/FIT being the most preferred method (2820 [58.5%]) vs colonoscopy (1958 [40.6%]; P < .001) or other screening tests (46 [1.0%] P < .001). Preference for FOBT/FIT was strongest in the West (963 of 1472 [65.4%]) and modest elsewhere, ranging from 199 of 371 (53.6%) in the Northeast to 884 of 1543 (57.3%) in the Midwest (P = .001). Adjusting for region, the preference for FOBT/FIT increased by 19% per recruitment year (odds ratio, 1.19; 95% CI, 1.14-1.25). Conclusions and Relevance: In this cross-sectional analysis of veterans choosing nonenrollment in the CONFIRM study, those who declined participation more often preferred FOBT or FIT over colonoscopy. This preference increased over time and was strongest in the western US and may provide insight into trends in CRC screening preferences.

Primary sclerosing cholangitis and pancreatic cancer: A retrospective cohort study of United States veterans.

Primary sclerosing cholangitis (PSC) is associated with hepatobiliary and colorectal cancers, but it remains uncertain if PSC increases the risk for pancreatic cancer. While some European studies have suggested an increased risk of pancreatic cancer in PSC patients, other studies have not. And these studies did not well account for presence or absence of concomitant inflammatory bowel disease (IBD). The purpose of this study is to investigate the prevalence of pancreatic cancer in United States veterans with PSC both with and without IBD. Methods: This retrospective study used International Classification of Diseases, Tenth Revision (ICD-10) codes to identify patients with PSC, IBD, and pancreatic cancer from the Veterans Affairs (VA) Corporate Data Warehouse. The prevalence of pancreatic cancer in patients with PSC only, IBD only, PSC with IBD, and neither PSC nor IBD were compared. Logistic regression was used to control for age, gender, chronic pancreatitis, diabetes mellitus, and tobacco and alcohol use. Results: A total of 946 patients with PSC were identified from a population of over 9 million veterans. 486 (51.4%) of these had concurrent IBD. Additionally 112,653 patients with IBD without PSC were identified. When adjusted for confounding factors, patients with PSC had a significantly higher prevalence of pancreatic cancer compared to the general population and those with IBD without PSC (2.4% vs. 0.2% and 0.5%, respectively). Conclusions: Veterans with PSC, particularly those without concomitant IBD, have a high prevalence of pancreatic cancer compared to the general veteran population. Our findings support the need for multicenter prospective studies investigating the benefits of screening for pancreatic cancer in patients with PSC.

Randomized Trial of Medical versus Surgical Treatment for Refractory Heartburn.

BACKGROUND: Heartburn that persists despite proton-pump inhibitor (PPI) treatment is a frequent clinical problem with multiple potential causes. Treatments for PPI-refractory heartburn are of unproven efficacy and focus on controlling gastroesophageal reflux with reflux-reducing medication (e.g., baclofen) or antireflux surgery or on dampening visceral hypersensitivity with neuromodulators (e.g., desipramine). METHODS: Patients who were referred to Veterans Affairs (VA) gastroenterology clinics for PPI-refractory heartburn received 20 mg of omeprazole twice daily for 2 weeks, and those with persistent heartburn underwent endoscopy, esophageal biopsy, esophageal manometry, and multichannel intraluminal impedance-pH monitoring. If patients were found to have reflux-related heartburn, we randomly assigned them to receive surgical treatment (laparoscopic Nissen fundoplication), active medical treatment (omeprazole plus baclofen, with desipramine added depending on symptoms), or control medical treatment (omeprazole plus placebo). The primary outcome was treatment success, defined as a decrease of 50% or more in the Gastroesophageal Reflux Disease (GERD)-Health Related Quality of Life score (range, 0 to 50, with higher scores indicating worse symptoms) at 1 year. RESULTS: A total of 366 patients (mean age, 48.5 years; 280 men) were enrolled. Prerandomization procedures excluded 288 patients: 42 had relief of their heartburn during the 2-week omeprazole trial, 70 did not complete trial procedures, 54 were excluded for other reasons, 23 had non-GERD esophageal disorders, and 99 had functional heartburn (not due to GERD or other histopathologic, motility, or structural abnormality). The remaining 78 patients underwent randomization. The incidence of treatment success with surgery (18 of 27 patients, 67%) was significantly superior to that with active medical treatment (7 of 25 patients, 28%; P = 0.007) or control medical treatment (3 of 26 patients, 12%; P<0.001). The difference in the incidence of treatment success between the active medical group and the control medical group was 16 percentage points (95% confidence interval, -5 to 38; P = 0.17). CONCLUSIONS: Among patients referred to VA gastroenterology clinics for PPI-refractory heartburn, systematic workup revealed truly PPI-refractory and reflux-related heartburn in a minority of patients. For that highly selected subgroup, surgery was superior to medical treatment. (Funded by the Department of Veterans Affairs Cooperative Studies Program; ClinicalTrials.gov number, NCT01265550.).

Benefit of N-Acetylcysteine in Postoperative Hepatic Dysfunction: Case Report and Review of Literature.

N-Acetylcysteine (NAC) is reported to have multiple clinical applications in addition to being the specific antidote for acetaminophen toxicity. NAC stimulates glutathione biosynthesis, promotes detoxification, and acts directly as a scavenger of free radicals. It is a powerful antioxidant and a potential treatment option for diseases characterized by the generation of free oxygen radicals. We present a case of postoperative hepatic dysfunction of multifactorial etiology in a patient with therapeutic acetaminophen levels, where hepatic function improved considerably following administration of intravenous NAC. This case suggests that NAC should be considered for treatment of acute liver dysfunction in the postoperative setting, even in the absence of elevated acetaminophen levels.

Bacterial Baptism: Scientific, Medical, and Regulatory Issues Raised by Vaginal Seeding of C-Section-Born Babies.

Several lines of evidence suggest that children born via Cesarean section (C-section) are at greater risk for adverse health outcomes including allergies, asthma and obesity. Vaginal seeding is a medical procedure in which infants born by C-section are swabbed immediately after birth with vaginal secretions from the mother. This procedure has been proposed as a way to transfer the mother's vaginal microbiome to the child, thereby restoring the natural exposure that occurs during vaginal birth that is interrupted in the case of babies born via C-section. Preliminary evidence indicates partial restoration of microbes. However, there is insufficient evidence to determine the health benefits of the procedure. Several studies, including trial, are currently underway. At the same time, in the clinic setting, doctors are increasingly being asked to by expectant mothers to have their babies seeded. This article reports on the current research on this procedure and the issues it raises for regulators, researchers, physicians, and patients.

Cytokines Are Markers of the Clostridium difficile-Induced Inflammatory Response and Predict Disease Severity.

The host immune response affects pathogen virulence in Clostridium difficile infection (CDI). Thus, cytokine responses to CDI likely are associated with disease initiation and progression. Understanding the molecular drivers of inflammation and biochemical markers of disease severity is important for developing novel therapies and predicting disease prognosis. In this study, we investigated cytokine production in patients with CDI and evaluated the potential of cytokines to serve as biomarkers for CDI and predictors of disease severity. The systemic cytokine profiles of 36 CDI patients (20 with severe disease) and 8 healthy donors and the toxin-induced cytokine profiles of peripheral blood mononuclear cells (PBMC) were determined. Further, we evaluated glucosyltransferase (GT) activity in regulation of toxin-induced cytokine expression. We found upregulation of the majority of measured cytokines (11/20, 55%) in CDI patients. Interleukin-1ß (IL-1ß), IL-6, IL-8, IL-17A, and IL-16 were the most upregulated. High serum levels of IL-2 and IL-15 were associated with a poor prognosis in CDI patients, whereas high levels of IL-5 and gamma interferon (IFN-γ) were associated with less severe disease. Both TcdA and TcdB were potent inducers of cytokine responses, as demonstrated by stimulation of a greater number and amount of cytokines. In addition to confirming prior reports on the role of IL-8, IL-1ß, and IL-6 in CDI, our data suggest that IL-16 and IL-17A, as well as the IL-1ß/Th17 axis, play a key role in driving inflammatory responses in CDI. A functional GT domain of C. difficile toxins was required for the induction of a majority of cytokines investigated.

Type IV pili promote early biofilm formation by Clostridium difficile.

Increasing morbidity and mortality from Clostridium difficile infection (CDI) present an enormous challenge to healthcare systems. Clostridium difficile express type IV pili (T4P), but their function remains unclear. Many chronic and recurrent bacterial infections result from biofilms, surface-associated bacterial communities embedded in an extracellular matrix. CDI may be biofilm mediated; T4P are important for biofilm formation in a number of organisms. We evaluate the role of T4P in C. difficile biofilm formation using RNA sequencing, mutagenesis and complementation of the gene encoding the major pilin pilA1, and microscopy. RNA sequencing demonstrates that, in comparison to other growth phenotypes, C. difficile growing in a biofilm has a distinct RNA expression profile, with significant differences in T4P gene expression. Microscopy of T4P-expressing and T4P-deficient strains suggests that T4P play an important role in early biofilm formation. A non-piliated pilA1 mutant forms an initial biofilm of significantly reduced mass and thickness in comparison to the wild type. Complementation of the pilA1 mutant strain leads to formation of a biofilm which resembles the wild-type biofilm. These findings suggest that T4P play an important role in early biofilm formation. Novel strategies for confronting biofilm infections are emerging; our data suggest that similar strategies should be investigated in CDI.

Pseudomembranous colitis: Not always Clostridium difficile.

Although Clostridium difficile infection is the cause of most cases of pseudomembranous colitis, clinicians should consider less common causes, especially if pseudomembranes are seen on endoscopy but testing remains negative for C difficile or if presumed C difficile infection does not respond to treatment. Histologic review of colonic mucosal biopsy specimens can provide clues to the underlying cause.

Acute Hepatocellular Drug-Induced Liver Injury From Bupropion and Doxycycline.

The management and diagnosis of drug-induced liver injury (DILI) is often challenging, particularly when patients are taking multiple medications. We present a 29-year-old African American man who presented with jaundice and malaise after starting bupropion and doxycycline 2 weeks prior. He was found to have acute hepatocellular drug-induced liver injury with autoimmune features, and made a complete recovery with prednisone. Although bupropion and doxycycline are both known to cause liver toxicity, a closer inspection of the signature of liver injury and a review of prior related DILI cases assigns causality more to bupropion than doxycycline.

Identification of toxemia in patients with Clostridium difficile infection.

Toxemia can develop in Clostridium difficile-infected animals, and correlates with severe and fulminant disease outcomes. Circumstantial evidence suggests that toxemia may occur in patients with C. difficile infection (CDI), but positive diagnosis is extremely rare. We analyzed the potential for C. difficile toxemia in patients, determined its characteristics, and assessed challenges. C. difficile toxins in serum from patients were tested using an ultrasensitive cell-based assay and further confirmed by Rac1 glucosylation assay. The factors that hinder a diagnosis of toxemia were assessed, including investigation of toxin stability, the level of toxins-specific neutralizing antibodies in sera and its effect on diagnosis limits. CDI patients develop detectable toxemia in some cases (2.3%). Toxins were relatively stable in stored sera. Neutralizing anti-toxin antibodies were present during infection and positively correlated with the diagnosis limits. Thus, the masking effect of toxin-specific neutralizing antibodies is the major obstacle in diagnosing C. difficile toxemia using cell-based bioassays.

Unusually late-onset mycophenolate mofetil-related colitis.

PURPOSE: Serious gastrointestinal complications arising 13 years after the initiation of posttransplant immunosuppressant therapy with mycophenolate mofetil are reported. SUMMARY: Over a three-month period, a male heart transplant recipient who had taken oral mycophenolate mofetil (2 g daily) for 13 years as part of an immunosuppressant maintenance regimen developed diarrhea and weight loss leading to renal failure and metabolic acidosis. There was no evidence of opportunistic infection, and immunostaining for cytomegalovirus yielded negative results. Colonoscopy revealed areas of congested, erythematous, and nodular mucosa. Histological examination of mucosal biopsy specimens revealed pathological abnormalities typical of those seen in cases of mycophenolate mofetil-associated colitis. On discontinuation of mycophenolate mofetil use, the patient's diarrhea resolved and his renal function improved. Colitis, diarrhea, and other gastrointestinal complications are commonly reported in patients receiving mycophenolate mofetil, an immunosuppressant widely used to prevent rejection of solid organ or bone marrow transplants; however, the onset of such symptoms after more than a decade of continuous use of the drug has not been previously reported. This case suggests that mycophenolate mofetil toxicity should be considered in the evaluation of late-onset posttransplant diarrhea regardless of the duration of therapy. CONCLUSION: A 33-year-old man maintained on mycophenolate mofetil for 13 years after heart transplantation developed diarrhea, weight loss, and acute kidney injury over a three-month period. Colonoscopy and biopsy revealed pathological changes consistent with mycophenolate mofetil toxicity, and the patient's symptoms resolved after the drug was discontinued.

Pseudomembranous Colitis: Not Always Caused by Clostridium difficile.

Although classically pseudomembranous colitis is caused by Clostridium difficile, it can result from several etiologies. Certain medications, chemical injury, collagenous colitis, inflammatory bowel disease, ischemia, and other infectious pathogens can reportedly cause mucosal injury and subsequent pseudomembrane formation. We present the case of a middle-aged woman with vascular disease who was incorrectly diagnosed with refractory C. difficile infection due to the presence of pseudomembranes. Further imaging, endoscopy, and careful histopathology review revealed chronic ischemia as the cause of her pseudomembranous colitis and diarrhea. This case highlights the need for gastroenterologists to consider non-C. difficile etiologies when diagnosing pseudomembranous colitis.

Identification, immunogenicity, and cross-reactivity of type IV pilin and pilin-like proteins from Clostridium difficile.

The Gram-positive anaerobe Clostridium difficile is the major cause of nosocomial diarrhea; manifestations of infection include diarrhea, pseudomembranous colitis, and death. Genes for type IV pili, a bacterial nanofiber often involved in colonization and until relatively recently described only in Gram-negatives, are present in all members of the Clostridiales. We hypothesized that any pilins encoded in the C. difficile genome would be immunogenic, as has been shown with pilins from Gram-negative organisms. We describe nine pilin or pilin-like protein genes, for which we introduce a coherent nomenclature, in the C. difficile R20291 genome. The nine predicted pilin or pilin-like proteins have relatively conserved N-terminal hydrophobic regions, but diverge at their C-termini. Analysis of synonymous and nonsynonymous substitutions revealed evidence of diversifying selective pressure in two pilin genes. Six of the nine identified proteins were purified and used to immunize mice. Immunization of mice with each individual protein generated antibody responses that varied in titer and cross-reactivity, a notable result given the low amino acid sequence identity among the pilins. Further studies in other small mammals mirrored our results in mice. Our results illuminate components of the C. difficile type IV pilus and help identify targets for an anti-C. difficile vaccine.