Microbiota-Short Chain Fatty Acid Relationships and Microbial Substrate Preferences Vary Across the Spectrum of Irritable Bowel Syndrome (IBS).

Objective: Identifying microbial targets in irritable bowel syndrome (IBS) is challenged by dynamic microbiota-metabolite-host interactions. We aimed to assess microbial features associated with short chain fatty acids (SCFA) and determine if features were related to IBS symptoms, subtypes, and endophenotypes. Design: We performed an observational study of stool microbial metagenomes, stool SCFA, and IBS traits (stool form, stool bile acids, and colonic transit) in patients with IBS (IBS with constipation [IBS-C] IBS with diarrhea [IBS-D]) and healthy controls. We analyzed associations of microbiome composition with stool SCFA to identify microbe-SCFA relationships that were shared and distinct across groups. We compared gut microbiome-encoded potential for substrate utilization across groups and within a subset of participants selected by stool characteristics. In IBS-D, we compared stool microbiomes of patients with and without bile acid malabsorption (BAM). Results: Overall stool microbiome composition and abundances of individual taxa differed between groups. Increased abundances of several bacterial species were observed in IBS-D including Dorea sp. CAG:317.. Microbes-SCFA relationships varied across groups after accounting for transit and bile acids. Significant microbe-SCFA were common in IBS-D and several SCFA-producing species were inversely correlated with SCFA. Among participants selected by stool form characteristics, functional profiling demonstrated differential abundances of microbial genes/pathways for SCFA metabolism and degradation of carbohydrates and mucin across groups. SCFA-producing taxa were reduced in IBS-D with BAM. Conclusion: Microbe-SCFA associations differ across IBS subtypes and traits. Altered substrate preferences offer insights into functional microbiome traits and could be used as novel microbial IBS biomarkers. KEY MESSAGES: What is already known on this topic: The intestinal microbiota and its metabolites (e.g., short chain fatty acids [SCFA]) modulate irritable bowel syndrome (IBS) pathophysiology. What this study adds: We studied microbe-SCFA associations across IBS subtypes and endophenotypes to demonstrate (1) the intestinal microbiome plays distinct roles across IBS subtypes, (2) microbial substrate preferences vary between IBS subtypes and influences stool form, and (3) microbe-SCFA patterns may reveal key taxa that underlie shared and distinct microbial mechanisms across the IBS spectrum. How this study might affect research, practice or policy: Findings demonstrate that structural and functional features of the intestinal microbiome may represent unbiased microbial biomarkers for clinical and mechanistic IBS subtypes. Further study of these putative microbial targets as well as their interactions with diet- and host-specific traits should be pursued to develop individualized microbiome-based approached to IBS management.

Associations of Fecal Short Chain Fatty Acids With Colonic Transit, Fecal Bile Acid, and Food Intake in Irritable Bowel Syndrome.

INTRODUCTION: Short-chain fatty acids (SCFAs) correlate with colonic transit time (CTT) and may influence irritable bowel syndrome (IBS) pathophysiology. However, the clinical significance of fecal SCFAs, relationships between SCFAs and other metabolites (bile acids [BAs]), and real-time diet effects on SCFAs in IBS are uncertain. The aim was to evaluate fecal SCFA associations with IBS phenotype and mechanisms and explore effects of real-time diet. METHODS: We conducted a prospective observational study of fecal SCFA, BAs, and CTT in healthy controls (HCs) and participants with IBS. We compared study end points across groups, analyzed relationships between end points, and evaluated the discriminative ability of SCFAs. Diet effects were explored in participants with dietary data. RESULTS: Among 21 HCs and 43 participants with IBS, fecal SCFAs (total, individual) were inversely correlated with overall (all P < 0.01) and segmental (all P < 0.05) CTT; similar associations were observed within HC and IBS groups. The acetate-to-butyrate ratio correlated with slower overall and left CTT in all and in HCs (both P < 0.01). SCFAs (total, acetate) correlated with BAs (total, % primary) in all participants and in those with IBS with diarrhea. Logistic regression analyses demonstrated associations of acetate with slower transit (odds ratio = 0.988, P = 0.002) and BA diarrhea (BAD; odds ratio = 1.014, P = 0.001). Acetate accurately predicted delayed CTT (area under the receiving operating characteristic curve = 0.84) and BAD (area under the receiver operating characteristic curve = 0.79). Adjusting for diet strengthened correlations of total SCFAs with overall CTT ( R = [-0.46], P = 0.04) and SCFAs with transverse CTT (all P < 0.05). DISCUSSION: Fecal SCFAs correlate with CTT and fecal BAs and reliably exclude delayed CTT and BAD. Accounting for diet strengthens SCFA associations with transit.

Prevalence of Staphylococcus aureus and methicillin-resistant S aureus on environmental surfaces in Ohio nursing homes.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is common in medical institutions. We sought to examine the prevalence of S aureus on environmental surfaces in nursing homes and to obtain molecular information on contaminating strains. METHODS: A total of 259 environmental samples were collected from 7 different nursing homes in Northeast Ohio (NEO), from suburban, urban, and rural settings. The presence of the mecA and PVL genes was determined, and spa typing was performed in order to identify molecular types. RESULTS: The prevalence of S aureus was 28.6% (74/259). The prevalence of MRSA and methicillin-susceptible S aureus was 20.1% (52/259) and 8.5% (22/259), respectively. S aureus contamination in suburban, urban, and rural sites was 25.7% (38/148), 45.9% (34/74), and 5.4% (2/37), respectively. MRSA was detected in 16.9% (25/148) of suburban samples and 36.5% (27/74) of urban samples. No MRSA was found in rural samples. Nursing homes from urban areas had a significantly higher (P < .001) prevalence of S aureus compared to nursing homes from suburban and rural sites. Areas with high nurse touch rates were the most commonly contaminated. CONCLUSIONS: We found differences in the prevalence of S aureus and MRSA in nursing homes in different regions of NEO. Part of these differences may result from transfers from hospitals; the urban nursing homes had 4 to 15 hospitals nearby, whereas suburban and rural locations had 1 to 3 hospitals within the area.

Multidrug-resistant Staphylococcus aureus Colonization in Healthy Adults Is more Common in Bhutanese Refugees in Nepal than Those Resettled in Ohio.

Although studies have shown that human migration is one of the risk factors for the spread of drug-resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA), surveillance studies examining MRSA among refugee populations in the US are lacking. This study aimed to assess the prevalence and molecular characteristics of S. aureus among Bhutanese refugees living in Nepal and resettled in Northeast Ohio (NEO). One hundred adult Bhutanese refugees from each geographic location were enrolled between August 2015 and January 2016. The participants were interviewed to collect demographic information and potential risk factors for carriage. Nasal and throat swabs were collected for bacterial isolation. All S. aureus isolates were characterized by spa typing and tested for the presence of Panton-Valentine leukocidin (PVL) and mecA genes; selected isolates were tested by multilocus sequence typing (MLST). The overall prevalence of S. aureus was 66.0% and 44.0% in NEO and Nepal, respectively. In Nepal, 5.8% (3/52) of isolates were MRSA and 1.1% (1/88) in NEO. Twenty-one isolates in NEO (23.9%) were multidrug-resistant S. aureus (MDRSA), while 23 (44.2%) in Nepal were MDRSA. In NEO, 41 spa types were detected from 88 S. aureus isolates. In Nepal, 32 spa types were detected from 52 S. aureus isolates. spa types t1818 and t345 were most common in NEO and Nepal, respectively. The overall prevalence of PVL-positive isolates among S. aureus in Nepal and NEO was 25.0% and 10.2%. ST5 was the most common sequence type in both locations. Bhutanese refugees living in Nepal and resettled in NEO had high prevalence of S. aureus and MDRSA. The findings suggest a potential need for CA-MRSA surveillance among the immigrant population in the U S and among people living in Nepal, and a potential need to devise appropriate public health measures to mitigate the risk imposed by community-associated strains of S. aureus and MRSA.

Prevalence and Molecular Characterization of Staphylococcus aureus and Methicillin-resistant S. aureus on Children's Playgrounds.

BACKGROUND: Staphylococcus aureus is a major public health concern due to the emergence of virulent and drug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA). Although numerous studies have been conducted to assess the environmental contamination of S. aureus in health care and household settings, little is known about the prevalence and epidemiology of S. aureus, including MRSA, on environmental surfaces of children's playgrounds. This study investigated the prevalence and molecular epidemiology of S. aureus and MRSA at playgrounds in northeast Ohio. METHODS: A total of 280 environmental samples were collected from 10 playgrounds in northeast Ohio in July 2016. Sampling sites were selected based on playground size and availability of equipment located in both small and large cities and their suburbs. Samples were analyzed using established microbiology methods, and resulting S. aureus isolates were typed by spa typing. Polymerase chain reaction was used to detect the presence of the Panton-Valentine leukocidin and mec A genes. Antibiotic susceptibility was tested via the Vitek-2 System. RESULTS: The overall prevalence of S. aureus and MRSA was 31.8% (89/280) and 3.9% (11/280), respectively. A total of 43 spa types were detected from 257 S. aureus isolates. Overall, t189 was the most common spa type, accounting for 15.6% (40/257) of the isolates. Sixteen isolates (6.2%) were t002 (ST5/USA100), a common hospital-associated strain, and 11 isolates (4.3%) were t008 (ST8/USA300), a common community-associated strain. Five livestock-associated strain (t571/ST398) were also identified. Twenty-nine (11.3%) isolates were resistant to oxacillin, and 66 (25.7%) were multi-drug resistant S. aureus. CONCLUSIONS: The results of this study indicate that environmental surfaces of playgrounds in northeastern Ohio were contaminated with S. aureus and MRSA. These data reinforce the need for implementing effective prevention strategies to mitigate the risk imposed to children by environmental contamination of MRSA.

Environmental contamination with Staphylococcus aureus at a large, Midwestern university campus.

BACKGROUND: Staphylococcus aureus can cause minor to severe life-threatening infections. The changing epidemiology of S. aureus is of public health concern due to the emergence of multi-drug resistant (MDR) strains. Environmental surfaces play a crucial role in the transmission of S. aureus. The objective of this study was to examine environmental contamination and molecular characteristics of S. aureus in health professional-associated (HPA) and non-health professional-associated (NHPA) buildings at a large university. METHODS: A total of 152 environmental surface samples were collected from two HPA and two NHPA campus buildings. Bacterial culture and diagnostics were done using standard microbiology methods. Polymerase chain reaction was conducted to detect mecA and PVL genes. All isolates were spa typed. A subset of isolates was characterized via multi-locus sequence typing (MLST). All S. aureus isolates were tested for antibiotic susceptibility. RESULTS: The overall contamination of S. aureus and methicillin-resistant S. aureus (MRSA) was 22.4% (34/152) and 5.9% (9/152) respectively. Similar prevalence of contamination was found in HPA and NHPA buildings. A total of 17 different spa types were detected among 34 S. aureus isolates. The majority of the MRSA isolates belonged to clonal complex (CC) 8. One isolate was positive for PVL. Eleven different sequence types (STs) were detected from 17 tested isolates. ST8 was the most common. Twelve isolates (35.3%) were MDR. CONCLUSION: Almost 27% (9/34) of the isolates were MRSA. The highest contamination of S. aureus was found in high hand-touch areas such as door knobs, suggesting that human interaction in crowded environments such as academic institutions plays a crucial role in S. aureus/MRSA transmission via inanimate objects. Additionally, more than one-third of the isolates were MDR. These data reinforce the need to implement effective prevention strategies outside the healthcare setting to decrease the incidence of drug-resistant S. aureus infections.

Prevalence and molecular characterization of Staphylococcus aureus in commercially available meat over a one-year period in Iowa, USA.

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of infectious disease morbidity and mortality. Previous studies have confirmed the presence of S. aureus, including MRSA, on raw meat products. We investigated the prevalence and molecular epidemiology of S. aureus and MRSA in commercially-distributed antibiotic-free and conventional raw meat products (n = 3290) purchased in 8 Iowa retail stores weekly for a period of one year. Isolates were characterized using spa typing, and PCR was used to detect the presence of the Panton-Valentine leukocidin (PVL) and mecA genes. Quantitation of S. aureus on meat products was carried out one week per month. The prevalence of S. aureus on meat samples was 27.8% (913/3290). Compared to antibiotic-free meat samples, higher prevalence of both MRSA and methicillin-susceptible S. aureus (MSSA) were found in conventional meat samples. Among the S. aureus isolates, 18 were PVL-positive (1.9%) and 41 (4.5%) carried mecA. Phenotypic oxacillin resistance was observed for 17.1% (41/239) of the isolates tested, while 23% (55/239) were multi-drug resistant. A total of 132 spa types were detected from 913 contaminated meat samples. Overall, t002 was the most common spa type identified (137; 15.0%). The number of colony-forming units (CFU) per 10 g meat ranged from 2 to 517 (median: 8 CFU per 10 g of meat; mean: 28) with the highest bacterial load observed on turkey samples. These data reinforce the need to consider meat products as potential vehicles of S. aureus transmission from farm into human households, and the potential need for public health intervention programs pre and post-slaughter in meat processing facilities.

Characterization of Staphylococcus aureus in Goose Feces from State Parks in Northeast Ohio.

Staphylococcus aureus can colonize a range of species. Although numerous studies have isolated pathogenic bacteria from wild birds, very little is known regarding S. aureus and their potential to spread methicillin-resistant (MRSA) strains. The objective of this study was to determine the presence and molecular characteristics of S. aureus in geese fecal samples collected from ten state parks across Northeast Ohio (NEO). A total of 182 fecal samples from Canada geese (Branta canadensis) were collected in April 2015. Isolates were characterized using multi-locus sequence (MLST) and spa typing, as well as PCR to detect the presence of Panton-Valentine leukocidin (PVL), mecA, and scn genes. Antibiotic susceptibility testing was done via Vitek-2 system. The overall contamination by S. aureus in fecal samples was 7.1% (13/182); 7/182 (3.8%) were MRSA and 6/182 (3.3%) were methicillin-susceptible S. aureus (MSSA). One isolate was positive for PVL. A total of eight different spa types were observed. MLST included ST5, ST8, ST291, ST298, and ST2111. One (7.7%) MSSA isolate was multi-drug resistant. The S. aureus contamination in NEO state parks ranged from 0% (park 1, 4, 8, 9) to 35% (7/20) (park 5). Parks 2, 3, 6, and 7 had 5% (1/20) positive. The results of this study indicate that the feces of geese collected at various state parks in NEO may harbor S. aureus.

Prevalence and Characterization of Staphylococcus aureus and Methicillin-Resistant Staphylococcus aureus on Public Recreational Beaches in Northeast Ohio.

Staphylococcus aureus can cause severe life-threatening illnesses such as sepsis and endocarditis. Although S. aureus has been isolated from marine water and intertidal beach sand, only a few studies have been conducted to assess prevalence of S. aureus at freshwater recreational beaches. As such, we aimed to determine prevalence and molecular characteristics of S. aureus in water and sand at 10 freshwater recreational beaches in Northeast Ohio, USA. Samples were analyzed using standard microbiology methods, and resulting isolates were typed by spa typing and multilocus sequence typing. The overall prevalence of S. aureus in sand and water samples was 22.8% (64/280). The prevalence of methicillin-resistant S. aureus (MRSA) was 8.2% (23/280). The highest prevalence was observed in summer (45.8%; 55/120) compared to fall (4.2%; 5/120) and spring (10.0%; 4/40). The overall prevalence of Panton-Valentine leukocidin genes among S. aureus isolates was 21.4% (15/70), and 27 different spa types were identified. The results of this study indicate that beach sand and freshwater of Northeast Ohio were contaminated with S. aureus, including MRSA. The high prevalence of S. aureus in summer months and presence of human-associated strains may indicate the possibility of role of human activity in S. aureus contamination of beach water and sand. While there are several possible routes for S. aureus contamination, S. aureus prevalence was higher in sites with wastewater treatment plants proximal to the beaches.

Staphylococcus aureus and staphylococcal food-borne disease: an ongoing challenge in public health.

Staphylococcal food-borne disease (SFD) is one of the most common food-borne diseases worldwide resulting from the contamination of food by preformed S. aureus enterotoxins. It is one of the most common causes of reported food-borne diseases in the United States. Although several Staphylococcal enterotoxins (SEs) have been identified, SEA, a highly heat-stable SE, is the most common cause of SFD worldwide. Outbreak investigations have found that improper food handling practices in the retail industry account for the majority of SFD outbreaks. However, several studies have documented prevalence of S. aureus in many food products including raw retail meat indicating that consumers are at potential risk of S. aureus colonization and subsequent infection. Presence of pathogens in food products imposes potential hazard for consumers and causes grave economic loss and loss in human productivity via food-borne disease. Symptoms of SFD include nausea, vomiting, and abdominal cramps with or without diarrhea. Preventive measures include safe food handling and processing practice, maintaining cold chain, adequate cleaning and disinfection of equipment, prevention of cross-contamination in home and kitchen, and prevention of contamination from farm to fork. This paper provides a brief overview of SFD, contributing factors, risk that it imposes to the consumers, current research gaps, and preventive measures.

Choice of health-care facility after introduction of free essential health services in Nepal.

BACKGROUND: Choice of health-care services depends on patients' characteristics and the features of health-care facilities available. In Nepal, a significant proportion of health care is provided through the private sector, despite the introduction of free essential health care for all citizens in 2008. We sought to determine whether people chose private or public facilities in the first instance for acute health problems. We also assessed the reasons for their choice. MATERIALS AND METHODS: A cross-sectional survey was done by use of a questionnaire administered to 400 household heads in Jhapa district, Nepal. RESULTS: 272 (68%) respondents sought treatment from public health-care facilities in the first instance. On adjusted analysis, illiterate people were more likely to choose public facilities than people with higher secondary education (OR 5.47, P = 0.002). Similarly, lower-caste and religious-minority respondents were more likely to choose public facilities than disadvantaged janajati (OR 2.33, P = 0.01). Among respondents who used public facilities, 174 (64.0%) and 109 (40.0%) stated that that their choice was based on financial accessibility and physical accessibility, respectively. Among respondents who used private facilities, 65 (50.7%) and 54 (42.1%) said their choice was based on adequacy of resources/services and health-care delivery, respectively. CONCLUSION: A substantial portion of respondents used public health-care facilities in the first instance, mainly because of financial and physical accessibility rather than adequacy of resources or better health-care delivery. These results may indicate a positive impact of removal of user fees for public health-care facilities in Nepal, especially for impoverished people.