scholarly journals The Impact of pH on Clostridioides difficile Sporulation and Physiology

2019 ◽  
Vol 86 (4) ◽  
Author(s):  
Daniela Wetzel ◽  
Shonna M. McBride
Keyword(s):  
Phenotypic Diversity ◽  
Toxin Production ◽  
Low Ph ◽  
Spore Morphology ◽  
Content Type ◽  
Clostridioides Difficile ◽  
Alkaline Environments ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
The Impact

ABSTRACT Clostridioides difficile is a pathogenic bacterium that infects the human colon to cause diarrheal disease. Growth of the bacterium is known to be dependent on certain bile acids, oxygen levels, and nutrient availability in the intestine, but how the environmental pH can influence C. difficile is mostly unknown. Previous studies indicated that C. difficile modulates the intestinal pH, and prospective cohort studies have found a strong association between a more alkaline fecal pH and C. difficile infection. Based on these data, we hypothesized that C. difficile physiology can be affected by various pH conditions. In this study, we investigated the impact of a range of pH conditions on C. difficile to assess potential effects on growth, sporulation, motility, and toxin production in the strains 630Δerm and R20291. We observed pH-dependent differences in sporulation rate, spore morphology, and viability. Sporulation frequency was lowest under acidic conditions, and differences in cell morphology were apparent at low pH. In alkaline environments, C. difficile sporulation was greater for strain 630Δerm, whereas R20291 produced relatively high levels of spores in a broad range of pH conditions. Rapid changes in pH during exponential growth impacted sporulation similarly among the strains. Furthermore, we observed an increase in C. difficile motility with increases in pH, and strain-dependent differences in toxin production under acidic conditions. The data demonstrate that pH is an important parameter that affects C. difficile physiology and may reveal relevant insights into the growth and dissemination of this pathogen. IMPORTANCE Clostridioides difficile is an anaerobic bacterium that causes gastrointestinal disease. C. difficile forms dormant spores which can survive harsh environmental conditions, allowing their spread to new hosts. In this study, we determine how intestinally relevant pH conditions impact C. difficile physiology in the two divergent strains, 630Δerm and R20291. Our data demonstrate that low pH conditions reduce C. difficile growth, sporulation, and motility. However, toxin production and spore morphology were differentially impacted in the two strains at low pH. In addition, we observed that alkaline environments reduce C. difficile growth, but increase cell motility. When pH was adjusted rapidly during growth, we observed similar impacts on both strains. This study provides new insights into the phenotypic diversity of C. difficile grown under diverse pH conditions present in the intestinal tract, and demonstrates similarities and differences in the pH responses of different C. difficile isolates.

scholarly journals The impact of pH on Clostridioides difficile sporulation and physiology

2019 ◽  
Author(s):  
Daniela Wetzel ◽  
Shonna M. McBride
Keyword(s):  
Phenotypic Diversity ◽  
Gastrointestinal Disease ◽  
Low Ph ◽  
Spore Morphology ◽  
Clostridioides Difficile ◽  
Alkaline Environments ◽  
Acidic Conditions ◽  
Ph Conditions ◽  
The Impact ◽  
Toxin Formation

ABSTRACTClostridioides difficile is a pathogenic bacterium that infects the human colon to cause diarrheal disease. Growth of the bacterium is known to be dependent on certain bile acids, oxygen levels and nutrient availability in the intestine, but how the environmental pH can influence C. difficile is mostly unknown. Previous studies indicated that C. difficile modulates the intestinal pH, and prospective cohort studies have found a strong association between a more alkaline fecal pH and C. difficile infection. Based on these data we hypothesized that C. difficile physiology can be affected by various pH conditions. In this study, we investigated the impact of a range of pH conditions on C. difficile to assess potential effects on growth, sporulation, motility and toxin production in the strains 630∆erm and R20291. We observed pH-dependent differences in sporulation rate, spore morphology and viability. Sporulation frequency was lowest under acidic conditions, and differences in cell morphology were apparent at low pH. In alkaline environments, C. difficile sporulation was greater for strain 630∆erm, whereas R20291 produced relatively high levels of spores in a broad range of pH conditions. Rapid changes in pH during exponential growth impacted sporulation similarly among the strains. Furthermore, we observed an increase in C. difficile motility with increases in pH, and strain-dependent differences in toxin formation under acidic conditions. The data demonstrate that pH is an important parameter that affects C. difficile physiology and may reveal relevant insights into the growth and dissemination of this pathogen.IMPORTANCEClostridioides difficile is an anaerobic bacterium that causes gastrointestinal disease. C. difficile forms dormant spores, which can survive harsh environmental conditions, allowing their spread to new hosts. In this study, we determine how intestinally relevant pH conditions impact C. difficile physiology in the two divergent strains, 630∆erm and R20291. Our data demonstrate that low pH conditions reduce C. difficile growth, sporulation, and motility. However, toxin formation and spore morphology are differentially impacted in the strains at low pH. In addition, we observed that alkaline environments reduced C. difficile growth, but increased cell motility. When pH was adjusted rapidly during growth, we observed similar impacts on both strains. This study provides new insights into the phenotypic diversity of C. difficile grown under the diverse pH conditions present in the intestinal tract, and demonstrates similarities and differences in the pH responses of different C. difficile isolates.

scholarly journals c-di-GMP Inhibits Early Sporulation in Clostridioides difficile

mSphere ◽  
2021 ◽  
Author(s):  
Adrianne N. Edwards ◽  
Caitlin L. Willams ◽  
Nivedita Pareek ◽  
Shonna M. McBride ◽  
Rita Tamayo
Keyword(s):  
Life Cycle ◽  
Biofilm Formation ◽  
Toxin Production ◽  
Cyclic Diguanylate ◽  
Content Type ◽  
Critical Step ◽  
Clostridioides Difficile ◽  
Physiological Processes ◽  
Gastrointestinal Pathogen ◽  
The Impact

Many bacterial organisms utilize the small signaling molecule cyclic diguanylate (c-di-GMP) to regulate important physiological processes, including motility, toxin production, biofilm formation, and colonization. c-di-GMP inhibits motility and toxin production and promotes biofilm formation and colonization in the anaerobic, gastrointestinal pathogen Clostridioides difficile . However, the impact of c-di-GMP on C. difficile spore formation, a critical step in this pathogen’s life cycle, is unknown.

scholarly journals Spo0A Suppresses sin Locus Expression in Clostridioides difficile

mSphere ◽  
2020 ◽  
Vol 5 (6) ◽  
Author(s):  
Babita Adhikari Dhungel ◽  
Revathi Govind
Keyword(s):  
Diarrheal Disease ◽  
Toxin Production ◽  
The United States ◽  
Upstream Region ◽  
Pcr Analysis ◽  
Bacterial Cells ◽  
Master Regulator ◽  
Content Type ◽  
Clostridioides Difficile

ABSTRACT Clostridioides difficile is the leading cause of nosocomial infection and is the causative agent of antibiotic-associated diarrhea. The severity of the disease is directly associated with toxin production, and spores are responsible for the transmission and persistence of the organism. Previously, we characterized sin locus regulators SinR and SinR′ (we renamed it SinI), where SinR is the regulator of toxin production and sporulation. The SinI regulator acts as its antagonist. In Bacillus subtilis, Spo0A, the master regulator of sporulation, controls SinR by regulating the expression of its antagonist, sinI. However, the role of Spo0A in the expression of sinR and sinI in C. difficile had not yet been reported. In this study, we tested spo0A mutants in three different C. difficile strains, R20291, UK1, and JIR8094, to understand the role of Spo0A in sin locus expression. Western blot analysis revealed that spo0A mutants had increased SinR levels. Quantitative reverse transcription-PCR (qRT-PCR) analysis of its expression further supported these data. By carrying out genetic and biochemical assays, we show that Spo0A can bind to the upstream region of this locus to regulates its expression. This study provides vital information that Spo0A regulates the sin locus, which controls critical pathogenic traits such as sporulation, toxin production, and motility in C. difficile. IMPORTANCE Clostridioides difficile is the leading cause of antibiotic-associated diarrheal disease in the United States. During infection, C. difficile spores germinate, and the vegetative bacterial cells produce toxins that damage host tissue. In C. difficile, the sin locus is known to regulate both sporulation and toxin production. In this study, we show that Spo0A, the master regulator of sporulation, controls sin locus expression. Results from our study suggest that Spo0A directly regulates the expression of this locus by binding to its upstream DNA region. This observation adds new detail to the gene regulatory network that connects sporulation and toxin production in this pathogen.

scholarly journals Variation in brachiopod microstructure and isotope geochemistry under low pH–ocean acidification–conditions

2018 ◽  
Author(s):  
Facheng Ye ◽  
Hana Jurikova ◽  
Lucia Angiolini ◽  
Uwe Brand ◽  
Gaia Crippa ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Ocean Acidification ◽  
Isotope Geochemistry ◽  
Shell Growth ◽  
Low Ph ◽  
Secondary Layer ◽  
Ph Conditions ◽  
One Year ◽  
The Impact ◽  
Δ13c And Δ18o

Abstract. Throughout the last few decades and in the near future CO2–induced ocean acidification is potentially a big threat to marine calcite-shelled animals (e.g., brachiopods, bivalves, corals and gastropods). Despite the great number of studies focusing on the effects of acidification on shell growth, metabolism, shell dissolution and shell repair, the consequences on biomineral formation remain poorly understood, and only few studies addressed contemporarily the impact of acidification on shell microstructure and geochemistry. In this study, a detailed microstructure and stable isotope geochemistry investigation was performed on nine adult brachiopod specimens of Magellania venosa (Dixon, 1789), grown in the natural environment as well as in controlled culturing experiments at different pH conditions (ranging 7.35 to 8.15 ± 0.05) over different time intervals (214 to 335 days). Details of shell microstructural features, such as thickness of the primary layer, density and size of endopunctae and morphology of the basic structural unit of the secondary layer were analysed using scanning electron microscopy (SEM). Stable isotope compositions (δ13C and δ18O) were tested from the secondary shell layer along shell ontogenetic increments in both dorsal and ventral valves. Based on our comprehensive dataset, we observed that, under low pH conditions, M. venosa produced a more organic-rich shell with higher density of and larger endopunctae, and smaller secondary layer fibres, when subjected to about one year of culturing. Also, increasingly negative δ13C and δ18O values are recorded by the shell produced during culturing and are related to the CO2–source in the culture setup. Both the microstructural changes and the stable isotope results are similar to observations on brachiopods from the fossil record and strongly support the value of brachiopods as robust archives of proxies for studying ocean acidification events in the geologic past.

scholarly journals RstA Is a Major Regulator ofClostridioides difficileToxin Production and Motility

mBio ◽  
2019 ◽  
Vol 10 (2) ◽  
Author(s):  
Adrianne N. Edwards ◽  
Brandon R. Anjuwon-Foster ◽  
Shonna M. McBride
Keyword(s):  
Gene Expression ◽  
Dna Binding ◽  
Toxin Production ◽  
Toxin Gene ◽  
Dna Binding Domain ◽  
Content Type ◽  
Toxin Genes ◽  
Clostridioides Difficile ◽  
Species Specific ◽  
Toxin Gene Expression

ABSTRACTClostridioides difficileinfection (CDI) is a toxin-mediated diarrheal disease. Several factors have been identified that influence the production of the two majorC. difficiletoxins, TcdA and TcdB, but prior published evidence suggested that additional unknown factors were involved in toxin regulation. Previously, we identified aC. difficileregulator, RstA, that promotes sporulation and represses motility and toxin production. We observed that the predicted DNA-binding domain of RstA was required for RstA-dependent repression of toxin genes, motility genes, andrstAtranscription. In this study, we further investigated the regulation of toxin and motility gene expression by RstA. DNA pulldown assays confirmed that RstA directly binds therstApromoter via the predicted DNA-binding domain. Through mutational analysis of therstApromoter, we identified several nucleotides that are important for RstA-dependent transcriptional regulation. Further, we observed that RstA directly binds and regulates the promoters of the toxin genestcdAandtcdB, as well as the promoters for thesigDandtcdRgenes, which encode regulators of toxin gene expression. Complementation analyses with theClostridium perfringensRstA ortholog and a multispecies chimeric RstA protein revealed that theC. difficileC-terminal domain is required for RstA DNA-binding activity, suggesting that species-specific signaling controls RstA function. Our data demonstrate that RstA is a transcriptional repressor that autoregulates its own expression and directly inhibits transcription of the two toxin genes and two positive toxin regulators, thereby acting at multiple regulatory points to control toxin production.IMPORTANCEClostridioides difficileis an anaerobic, gastrointestinal pathogen of humans and other mammals.C. difficileproduces two major toxins, TcdA and TcdB, which cause the symptoms of the disease, and forms dormant endospores to survive the aerobic environment outside the host. A recently discovered regulatory factor, RstA, inhibits toxin production and positively influences spore formation. Herein, we determine that RstA directly binds its own promoter DNA to repress its own gene transcription. In addition, our data demonstrate that RstA directly represses toxin gene expression and gene expression of two toxin gene activators, TcdR and SigD, creating a complex regulatory network to tightly control toxin production. This study provides a novel regulatory link betweenC. difficilesporulation and toxin production. Further, our data suggest thatC. difficiletoxin production is regulated through a direct, species-specific sensing mechanism.

scholarly journals Cystic Fibrosis-AssociatedStenotrophomonas maltophiliaStrain-Specific Adaptations and Responses to pH

2019 ◽  
Vol 201 (7) ◽  
Author(s):  
Tara Gallagher ◽  
Joann Phan ◽  
Andrew Oliver ◽  
Alexander B. Chase ◽  
Whitney E. England ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Stenotrophomonas Maltophilia ◽  
Opportunistic Infections ◽  
Expression Profiles ◽  
Bacterial Colonization ◽  
Low Ph ◽  
Lung Damage ◽  
Ph Gradients ◽  
Content Type ◽  
The Impact

ABSTRACTThe airway fluids of cystic fibrosis (CF) patients contain local pH gradients and are more acidic than those of healthy individuals. pH is a critical factor that is often overlooked in studies seeking to recapitulate the infection microenvironment. We sought to determine the impact of pH on the physiology of a ubiqituous yet understudied microbe,Stenotrophomonas maltophilia. Phylogenomics was first used to reconstruct evolutionary relationships between 74 strains ofS. maltophilia(59 from CF patients). Neither the core genome (2,158 genes) nor the accessory genome (11,978 genes) distinguish the CF and non-CF isolates; however, strains from similar isolation sources grouped into the same subclades. We grew two human and six CFS. maltophiliaisolates from different subclades at a range of pH values and observed impaired growth and altered antibiotic tolerances at pH 5. Transcriptomes revealed increased expression of both antibiotic resistance and DNA repair genes in acidic conditions. Although the gene expression profiles ofS. maltophiliain lab cultures and CF sputum were distinct, we found that the same genes associated with low pH were also expressed during infection, and the higher pH cultures were more similar to sputum metatranscriptomes. Our findings suggest thatS. maltophiliais not well adapted to acidity and may cope with low pH by expressing stress response genes and colonizing less acidic microenvironments. As a whole, our study underlines the impact of microenvironments on bacterial colonization and adaptation in CF infections.IMPORTANCEUnderstanding bacterial responses to physiological conditions is an important priority for combating opportunistic infections. The majority of CF patients succumb to inflammation and necrosis in the airways, arising from chronic infection due to ineffective mucociliary clearance. Steep pH gradients characterize the CF airways but are not often incorporated in standard microbiology culture conditions.Stenotrophomonas maltophiliais a prevalent CF opportunistic pathogen also found in many disparate environments, yet this bacterium’s contribution to CF lung damage and its response to changing environmental factors remain largely understudied. Here, we show that pH impacts the physiology and antibiotic susceptibility ofS. maltophilia, with implications for the development of relevantin vitromodels and assessment of antibiotic sensitivity.

scholarly journals ZupT Facilitates Clostridioides difficile Resistance to Host-Mediated Nutritional Immunity

mSphere ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Joseph P. Zackular ◽  
Reece J. Knippel ◽  
Christopher A. Lopez ◽  
William N. Beavers ◽  
C. Noel Maxwell ◽  
...  
Keyword(s):  
Immune Response ◽  
Therapeutic Potential ◽  
Neutrophil Infiltration ◽  
Toxin Production ◽  
Host Protein ◽  
Content Type ◽  
Nutritional Immunity ◽  
Clostridioides Difficile ◽  
Therapeutic Development ◽  
Dependent Growth

ABSTRACT Clostridioides difficile is a spore-forming bacterium that causes severe colitis and is a major public health threat. During infection, C. difficile toxin production results in damage to the epithelium and a hyperinflammatory response. The immune response to CDI leads to robust neutrophil infiltration at the sight of infection and the deployment of numerous antimicrobials. One of the most abundant host immune factors associated with CDI is calprotectin, a metal-chelating protein with potent antimicrobial activity. Calprotectin is essential to the innate immune response to C. difficile and increasing levels of calprotectin correlate with disease severity in both adults and children with CDI. The fact that C. difficile persists in the presence of high levels of calprotectin suggests that this organism may deploy strategies to compete with this potent antimicrobial factor for essential nutrient metals during infection. In this report, we demonstrate that a putative zinc (Zn) transporter, ZupT, is employed by C. difficile to survive calprotectin-mediated metal limitation. ZupT is highly expressed in the presence of calprotectin and is required to protect C. difficile against calprotectin-dependent growth inhibition. When competing against wild-type C. difficile, zupT mutants show a defect in colonization and persistence in a murine model of infection. Together these data demonstrate that C. difficile utilizes a metal import system to combat nutritional immunity during CDI and suggest that strategies targeting nutrient acquisition in C. difficile may have therapeutic potential. IMPORTANCE During infection, pathogenic organisms must acquire essential transition metals from the host environment. Through the process of nutritional immunity, the host employs numerous strategies to restrict these key nutrients from invading pathogens. In this study, we describe a mechanism by which the important human pathogen Clostridioides difficile resists transition-metal limitation by the host. We report that C. difficile utilizes a zinc transporter, ZupT, to compete with the host protein calprotectin for nutrient zinc. Inactivation of this transporter in C. difficile renders this important pathogen sensitive to host-mediated metal restriction and confers a fitness disadvantage during infection. Our study demonstrates that targeting nutrient metal transport proteins in C. difficile is a potential avenue for therapeutic development.

scholarly journals 2435. The Impact of Treatment Strategy and Toxin Status on Outcomes of Patients with Clostridioides difficile Infections

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S842-S842
Author(s):  
Daniel Friedman ◽  
Karen Zurek ◽  
Leyla Asadi ◽  
Mao-Cheng Lee ◽  
Holly Hoang
Keyword(s):  
Treatment Guidelines ◽  
Retrospective Chart Review ◽  
Toxin Production ◽  
Toxin Gene ◽  
Composite Outcome ◽  
Related Complication ◽  
Clostridioides Difficile ◽  
Increased Risk ◽  
Treatment Escalation ◽  
The Impact

Abstract Background Clostridioides difficile infection (CDI) is an important cause of morbidity and mortality and management continues to evolve. For laboratories that diagnose by detection of toxin gene, it is unclear whether reporting toxin production is additive to patient care. Furthermore, is there still a role for metronidazole (MNZ) given treatment guidelines now recommend vancomycin (VAN) as first-line therapy for non-severe cases? We analyzed cases of CDI in our hospital to assess outcomes of patients on MNZ vs. VAN and with or without toxin production. Methods A retrospective chart review of inpatients with CDI (based on detection of C. difficile toxin gene by PCR) was conducted between November 2017 and August 2018. Comparison of demographics and outcomes was performed in a) cases that were toxin-positive by enzyme immunoassay vs. negative and b) non-severe cases initially managed with MNZ vs. VAN. Results 76 patients were included (46 toxin-positive, 30 toxin-negative). Toxin-positive patients were older (mean age 77 vs. 62, p = 0.002) but had similar disease severity and initial treatment. A CDI recurrence occurred in 22% vs 0% in the toxin-positive cases (p = 0.006). Any CDI-related complication occurred in 23% of toxin-negative and 35% of toxin-positive cases (ns). After adjusting for toxin-status, age, and severity, the odds ratio of the composite outcome of any complication with toxin-positive CDI was not significant (OR 1.45 95% CI 0.45 -4.6, p = 0.52). There were 37 (49%) patients with non-severe CDI (27 MNZ, 10 VAN). Patients treated with VAN had higher stooling/day (6.3 vs 4.4, p = 0.04) and heart rate (p = 0.02). Initial MNZ use was associated with treatment escalation in 48% of cases compared with 10% in those treated with VAN alone (p = 0.03). CDI-associated mortality was higher in the VAN group (2/10 vs 0/27, p = 0.017). The rate of other complications was not significantly different. Conclusion Although no difference in the composite outcome of any CDI-related complication was detected between toxin positive vs negative patients, toxin-positivity may predict patients at risk for subsequent recurrence. Patients with non-severe CDI did not have increased risk of complications when managed with MNZ; however, they were more likely to require treatment escalation. Disclosures All authors: No reported disclosures.

scholarly journals From Nursery to Nursing Home: Emerging Concepts in Clostridioides difficile Pathogenesis

2020 ◽  
Vol 88 (7) ◽  
Author(s):  
Alexander B. Smith ◽  
Joshua Soto Ocana ◽  
Joseph P. Zackular
Keyword(s):  
Pharmaceutical Drugs ◽  
Human Gastrointestinal Tract ◽  
Content Type ◽  
The Past ◽  
Clostridioides Difficile ◽  
Wide Range ◽  
Pediatric Populations ◽  
The Impact ◽  
Shed Light

ABSTRACT Clostridioides difficile is a Gram-positive, spore-forming, anaerobic bacterium that infects the human gastrointestinal tract, causing a wide range of disorders that vary in severity from mild diarrhea to toxic megacolon and/or death. Over the past decade, incidence, severity, and costs associated with C. difficile infection (CDI) have increased dramatically in both the pediatric and adult populations. The factors driving this rapidly evolving epidemiology remain largely unknown but are likely due in part to previously unappreciated host, microbiota, and environmental factors. In this review, we will cover the risks and challenges of CDI in adult and pediatric populations and examine asymptomatic colonization in infants. We will also discuss the emerging role of diet, pharmaceutical drugs, and pathogen-microbiota interactions in C. difficile pathogenesis, as well as the impact of host-microbiota interactions in the manifestation of C. difficile-associated disease. Finally, we highlight new areas of research and novel strategies that may shed light on this complex infection and provide insights into the future of microbiota-based therapeutics for CDI.

scholarly journals Impact of Currently Marketed Tampons and Menstrual Cups onStaphylococcus aureusGrowth and Toxic Shock Syndrome Toxin 1 ProductionIn Vitro

2018 ◽  
Vol 84 (12) ◽  
pp. e00351-18 ◽  
Author(s):  
Louis Nonfoux ◽  
Myriam Chiaruzzi ◽  
Cédric Badiou ◽  
Jessica Baude ◽  
Anne Tristan ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Toxic Shock Syndrome ◽  
Severe Disease ◽  
Toxin Production ◽  
Toxic Shock ◽  
Content Type ◽  
Physiological Conditions ◽  
Simple Protocol ◽  
Toxic Shock Syndrome Toxin ◽  
The Impact

ABSTRACTFifteen currently marketed intravaginal protection products (11 types of tampon and 4 types of menstrual cup) were tested by the modified tampon sac method to determine their effect onStaphylococcus aureusgrowth and toxic shock syndrome toxin 1 (TSST-1) production. Most tampons reducedS. aureusgrowth and TSST-1 production, with differences based on brand and composition, and the level ofS. aureusgrowth was higher in destructured than in unaltered tampons. We observed higher levels ofS. aureusgrowth and toxin production in menstrual cups than in tampons, potentially due to the additional air introduced into the bag by cups, with differences based on cup composition and size.IMPORTANCEMenstrual toxic shock syndrome is a rare but severe disease. It occurs in healthy women vaginally colonized byStaphylococcus aureusproducing toxic shock syndrome toxin 1 using intravaginal protection, such as tampons or menstrual cups. Intravaginal protection induces TSS by the collection of catamenial products, which act as a growth medium forS. aureus. Previous studies evaluated the impact of tampon composition onS. aureusproducing toxic shock syndrome toxin 1, but they are not recent and did not include menstrual cups. This study demonstrates that highly reproducible results forS. aureusgrowth and TSST-1 production can be obtained by using a simple protocol that reproduces the physiological conditions of tampon and cup usage as closely as possible, providing recommendations for tampon or cup use to both manufacturers and consumers. Notably, our results do not show that menstrual cups are safer than tampons and suggest that they require similar precautions.

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