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Infectious Disease Clinics of North... Jun 2024Urinary tract infections (UTIs) are common in women; more than 50% of women will be diagnosed with a UTI in her lifetime. Many of these women will go on to develop... (Review)
Review
Urinary tract infections (UTIs) are common in women; more than 50% of women will be diagnosed with a UTI in her lifetime. Many of these women will go on to develop recurrent UTI. Nevertheless, evidence-based prevention of recurrent UTI is under-utilized. Here, the authors provide detailed practical advice on UTI prevention with a thorough review of the evidence. Non-antibiotic prevention measures discussed include increased fluid intake, vaginal estrogen therapy, methenamine, and cranberry. Antibiotic prophyalxis for carefully selected patients is also discussed.
Topics: Humans; Urinary Tract Infections; Female; Risk Factors; Recurrence; Anti-Bacterial Agents; Secondary Prevention
PubMed: 38599896
DOI: 10.1016/j.idc.2024.03.010 -
International Urogynecology Journal Mar 2024Antibiotic resistance is an unavoidable consequence of antibiotic use and growing rates of resistance are an urgent issue. Methenamine is a non-antibiotic alternative... (Review)
Review
INTRODUCTION AND HYPOTHESIS
Antibiotic resistance is an unavoidable consequence of antibiotic use and growing rates of resistance are an urgent issue. Methenamine is a non-antibiotic alternative used for urinary tract infection (UTI) prophylaxis. The objective of this review is to evaluate recently published literature regarding the efficacy and safety of methenamine for UTI prophylaxis.
METHODS
PubMed, Embase, and CENTRAL databases were queried in March 2023 using the following search terms: urinary tract infection, cystitis, bacteriuria, or dysuria, and methenamine. Studies prior to 2012 were excluded from this review to focus on appraisal of the most recent evidence. Prospective and controlled retrospective trials were included for review.
RESULTS
A total of seven studies (three prospective and four retrospective) met the inclusion criteria for review. Two of the 3 prospective studies demonstrated no or non-inferior differences in clinical efficacy to prevent recurrent UTIs between methenamine and antibiotic prophylaxis and the third showed decreased rates of UTI with methenamine use in patients with short-term indwelling catheters compared with cranberry alone. The retrospective studies consistently supported the efficacy and safety of methenamine for UTI prophylaxis in a variety of populations and clinical settings. Adverse effects reported with methenamine were similar to comparators and included nausea, abdominal pain, and headache.
CONCLUSIONS
The use of methenamine for UTI prophylaxis was shown to be effective in a variety of settings without an increased risk of adverse effects compared with prophylactic antibiotics. Larger blinded clinical trials are needed to further define the role of methenamine in UTI prophylaxis.
Topics: Humans; Methenamine; Prospective Studies; Retrospective Studies; Urinary Tract Infections; Anti-Bacterial Agents; Antibiotic Prophylaxis
PubMed: 38329493
DOI: 10.1007/s00192-024-05726-2 -
Current Opinion in Urology Nov 2023Recurrent urinary tract infections (rUTIs) in women are prevalent and difficult to manage. The rise of antimicrobial resistance makes it prudent to re-investigate the...
PURPOSE OF REVIEW
Recurrent urinary tract infections (rUTIs) in women are prevalent and difficult to manage. The rise of antimicrobial resistance makes it prudent to re-investigate the role of nonantimicrobial agents in the prevention of RUTIs. We wanted to evaluate randomised controlled trials (RCTs) that employed methenamine hippurate as a therapy or prophylactic in adult women with rUTIs.
RECENT FINDINGS
Relevant databases were searched for RCTs using Cochrane methodology and reporting items for systematic reviews and meta-analyses (PRISMA) checklist, comparing the efficacy of methenamine hippurate to either an antibiotic or a placebo for the prophylaxis of rUTI in women.Six trials involving 322 patients taking methenamine and 419 patients receiving antibiotics in total were evaluated. The duration of the trials ranged from 12-24 months. Studies reported that methenamine was effective in extending the mean period between symptomatic episodes of urinary tract infections (UTIs), keeping the patient symptom- and infection-free, and reducing the number of UTI episodes. The newer studies reported that methenamine reduced the incidence rates of recurrent UTIs and was not inferior to the antibiotic in this regard.
SUMMARY
The outcomes of methenamine hippurate were found to be at par with the antibiotic prophylaxis. It might serve as a suitable alternative nonantibiotic prophylaxis for females with rUTIs.
Topics: Adult; Female; Humans; Methenamine; Urinary Tract Infections; Hippurates; Anti-Bacterial Agents
PubMed: 37337660
DOI: 10.1097/MOU.0000000000001108 -
Pharmacotherapy Feb 2024Urinary tract infections (UTIs) commonly affect many patient populations. Recurrent UTIs (rUTIs) can be particularly problematic and lead to potential hospitalizations,... (Review)
Review
Urinary tract infections (UTIs) commonly affect many patient populations. Recurrent UTIs (rUTIs) can be particularly problematic and lead to potential hospitalizations, multiple antibiotic courses, and have a potential negative impact on quality of life. To prevent UTIs, antibiotics are frequently used for prophylaxis; however, antibiotic prophylaxis has notable untoward consequences including but not limited to potential adverse effects and development of antibiotic resistance. Methenamine, an antiseptic agent initially available in 1967, has re-emerged as a potential option for UTI prophylaxis in various populations, including older adults and renal transplant recipients. The objective of this systematic review was to evaluate the clinical effectiveness and safety of methenamine for UTI prophylaxis. A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance was performed. A PubMed, Embase, and Cochrane library search was conducted to identify relevant English-language studies evaluating methenamine for UTI prophylaxis including randomized controlled trials, case-control studies, and meta-analyses through June 2023. Articles were excluded if the studies did not primarily describe or evaluate methenamine for UTI prophylaxis, were commentaries/viewpoints articles, point prevalence studies, review articles, studies that evaluated methenamine used with another agent, and any duplicate publications from searched databases. A total of 11 articles were identified for inclusion. This systematic review suggests methenamine generally appears to be an effective and well-tolerated antibiotic-sparing option for UTI prophylaxis. Furthermore, the pharmacology, dosage and formulation, warnings, precautions, and safety considerations of methenamine that provide potential clinical considerations regarding its use for UTI prophylaxis are described. Further studies are needed to evaluate the clinical utility of methenamine for UTI prophylaxis.
Topics: Humans; Aged; Methenamine; Quality of Life; Urinary Tract Infections; Anti-Bacterial Agents; Treatment Outcome; Antibiotic Prophylaxis
PubMed: 37986168
DOI: 10.1002/phar.2895 -
Annals of Medicine Dec 2023To evaluate diagnostic performance of metagenomic next-generation sequencing (mNGS) for pneumonia (PCP), in comparison with polymerase chain reaction (PCR), Gomori...
AIM
To evaluate diagnostic performance of metagenomic next-generation sequencing (mNGS) for pneumonia (PCP), in comparison with polymerase chain reaction (PCR), Gomori methenamine silver (GMS) staining and serum 1,3-β-d-Glucan (BG) assay.
METHODS
52 PCP patients and 103 patients with non-pneumocystic jirovecii pneumonia (non-PCP) were enrolled, and comparative analysis was conducted of different diagnostic tests. Clinical features and co-pathogen characteristics were reviewed.
RESULTS
The diagnostic sensitivity (92.3%) and specificity (87.4%) of mNGS did not show significant differences compared with that of PCR while mNGS had the advantage over PCR in the detection of co-pathogens. Despite its excellent specificity, the sensitivity of GMS staining (9.3%) was inferior to that of mNGS ( < .001). The combination of mNGS with serum BG statistically outperformed mNGS or serum BG alone in the areas under the receiver operating characteristic curves (AUCs, = .0013 and = .0015, respectively). Notably, all the blood samples showing positive mNGS for came from PCP patients. The leading co-pathogens among patients with PCP were cytomegalovirus, Epstein-Barr virus and Torque teno virus.
CONCLUSIONS
mNGS shows superiority over several common clinical methods in the diagnosis of suspected PCP. Serum BG in conjunction with mNGS further improved the diagnostic efficacy of mNGS.
Topics: Humans; Pneumonia, Pneumocystis; Epstein-Barr Virus Infections; Sensitivity and Specificity; Herpesvirus 4, Human; High-Throughput Nucleotide Sequencing; Respiratory System
PubMed: 37403381
DOI: 10.1080/07853890.2023.2232358 -
Indian Dermatology Online Journal 2023A few recent studies have shown fungal elements within the hair follicle epithelium, which may act as a reservoir and responsible for recurrent dermatophytosis.
BACKGROUND
A few recent studies have shown fungal elements within the hair follicle epithelium, which may act as a reservoir and responsible for recurrent dermatophytosis.
OBJECTIVES
To assess the clinical patterns, mycological profile, and histopathology of recurrent dermatophytosis and to determine the prevalence of fungal hyphae in the hair follicle epithelium and other appendages.
MATERIALS AND METHODS
One hundred and fifty clinically diagnosed cases of recurrent dermatophytic infection were included. Skin samples were taken for direct microscopy, fungal culture, and histopathological analysis. Haematoxylin and eosin and special staining with periodic acid Schiff (PAS) and Gomori's methenamine silver (GMS) were performed to detect the fungal hyphae in the skin and hair follicle epithelium.
RESULTS
The most common clinical pattern observed was tinea corporis et cruris in 64 patients (42.66%). On direct microscopy and fungal culture, positive results were obtained in 116 cases (77.33%) and 78 (52%) cases, respectively. Presence of fungal hyphae in the stratum corneum, hair follicle, and acrosyringium was seen in 107 patients (71.33%), 47 patients (31.33%), and five patients (3.33%), respectively. Out of the 52 cases with hair follicle and eccrine gland involvement, history of fixed drug combinations (FDC) cream use was present in 42 cases (80.76%) and absent in ten cases (19.24%) ( = 0.000062).
LIMITATIONS
Skin samples were taken only from a single skin lesion. Higher incidence of follicular invasion may have been detected if multiple biopsy samples were taken.
CONCLUSION
Hair follicle/eccrine sweat gland involvement was observed in nearly one-third of the patients, which may act as a reservoir and may be responsible for recurrence and chronicity. Histopathology should be considered as an important adjuvant tool in recurrent dermatophytosis to establish the extent of the infection, which guides the further management.
PubMed: 38099009
DOI: 10.4103/idoj.idoj_670_22 -
PLoS Pathogens May 2024The role of bacteria in the etiology of dental caries is long established, while the role of fungi has only recently gained more attention. The microbial invasion of...
The role of bacteria in the etiology of dental caries is long established, while the role of fungi has only recently gained more attention. The microbial invasion of dentin in advanced caries especially merits additional research. We evaluated the fungal and bacterial community composition and spatial distribution within carious dentin. Amplicon 16S rRNA gene sequencing together with quantitative PCR was used to profile bacterial and fungal species in caries-free children (n = 43) and 4 stages of caries progression from children with severe early childhood caries (n = 32). Additionally, healthy (n = 10) and carious (n = 10) primary teeth were decalcified, sectioned, and stained with Grocott's methenamine silver, periodic acid Schiff (PAS) and calcofluor white (CW) for fungi. Immunolocalization was also performed using antibodies against fungal β-D-glucan, gram-positive bacterial lipoteichoic acid, gram-negative endotoxin, Streptococcus mutans, and Candida albicans. We also performed field emission scanning electron microscopy (FESEM) to visualize fungi and bacteria within carious dentinal tubules. Bacterial communities observed included a high abundance of S. mutans and the Veillonella parvula group, as expected. There was a higher ratio of fungi to bacteria in dentin-involved lesions compared to less severe lesions with frequent preponderance of C. albicans, C. dubliniensis, and in one case C. tropicalis. Grocott's silver, PAS, CW and immunohistochemistry (IHC) demonstrated the presence of fungi within carious dentinal tubules. Multiplex IHC revealed that fungi, gram-negative, and gram-positive bacteria primarily occupied separate dentinal tubules, with rare instances of colocalization. Similar findings were observed with multiplex immunofluorescence using anti-S. mutans and anti-C. albicans antibodies. Electron microscopy showed monomorphic bacterial and fungal biofilms within distinct dentin tubules. We demonstrate a previously unrecognized phenomenon in which fungi and bacteria occupy distinct spatial niches within carious dentin and seldom co-colonize. The potential significance of this phenomenon in caries progression warrants further exploration.
Topics: Humans; Dental Caries; Dentin; Male; Child; Female; Child, Preschool; Bacteria; Fungi; RNA, Ribosomal, 16S
PubMed: 38805482
DOI: 10.1371/journal.ppat.1011865 -
Journal of Colloid and Interface Science Aug 2023Carbon frameworks with well-developed porosity present broad application prospects in energy-related materials, and green preparation still face challenges. Herein, the...
Carbon frameworks with well-developed porosity present broad application prospects in energy-related materials, and green preparation still face challenges. Herein, the tannins-derived framework-like carbon material is obtained by cross-linking and self-assembly strategy.The phenolic hydroxyl and quinones in tannin cross-linking react with the amine groups in the methenamine by simple stirring, which drives the self-assembly of tannins and methenamine,contributing to the reaction products being precipitated in solution as aggregates with framework-like structure. The porosity and micromorphology of framework-like structures are further enriched by the thermal stability difference between tannin and methenamine. The methenamine of framework-like structures is entirely removed by the sublimation and decomposition and the tannin is transformed into carbon materials inheriting framework-like structures after the carbonization, which offers the path for rapid electron transport. The framework-like structure, excellent specific surface area and nitrogen doping give the assembled Zn-ion hybrid supercapacitors a superior specific capacitance of 165.3 mAh·g (350.4 F·g). This device could be charged to 1.87 V to power the bulb by using solar panels. This study proves that the tannin-derived framework-like carbon is a promising electrode of the Zn-ion hybrid supercapacitors, which is beneficial for value-added and industrial supercapacitors application of green feedstocks.
PubMed: 37141782
DOI: 10.1016/j.jcis.2023.04.112 -
American Family Physician Feb 2024An acute uncomplicated urinary tract infection (UTI) is a bacterial infection of the lower urinary tract with no sign of systemic illness or pyelonephritis in a...
An acute uncomplicated urinary tract infection (UTI) is a bacterial infection of the lower urinary tract with no sign of systemic illness or pyelonephritis in a noncatheterized, nonpregnant adult with no urologic abnormalities or immunocompromise. In women, a self-diagnosis of a UTI with the presence of typical symptoms (e.g., frequency, urgency, dysuria/burning sensation, nocturia, suprapubic pain), without vaginal discharge, is accurate enough to diagnose an uncomplicated UTI without further testing. Urine culture and susceptibility testing should be reserved for women with recurrent infection, treatment failure, history of resistant isolates, or atypical presentation to make a definitive diagnosis and guide antibiotic selection. First-line antibiotics include nitrofurantoin for five days, fosfomycin in a single dose, trimethoprim for three days, or trimethoprim/sulfamethoxazole for three days. Symptomatic treatment with nonsteroidal anti-inflammatory drugs and delayed antibiotics may be considered because the risk of complications is low. Increased fluids, intake of cranberry products, and methenamine hippurate can prevent recurrent infections. Antibiotic prophylaxis is also effective in preventing recurrence but has a risk of adverse effects and antimicrobial resistance. Men with lower UTI symptoms should always receive antibiotics, with urine culture and susceptibility results guiding the antibiotic choice. Clinicians should also consider the possibility of urethritis and prostatitis in men with UTI symptoms. First-line antibiotics for men with uncomplicated UTI include trimethoprim, trimethoprim/sulfamethoxazole, and nitrofurantoin for seven days. Uncomplicated UTIs in nonfrail women and men 65 years and older with no relevant comorbidities also necessitate a urine culture with susceptibility testing to adjust the antibiotic choice after initial empiric treatment; first-line antibiotics and treatment durations do not differ from those recommended for younger adults.
Topics: Adult; Female; Humans; Male; Anti-Bacterial Agents; Fosfomycin; Nitrofurantoin; Trimethoprim, Sulfamethoxazole Drug Combination; Urinary Tract Infections
PubMed: 38393801
DOI: No ID Found -
Veterinary Clinical Pathology Dec 2023Silica from plastic red top sample collection tubes and barium cause recognized artifacts in slide preparations for microscopic examination.
BACKGROUND
Silica from plastic red top sample collection tubes and barium cause recognized artifacts in slide preparations for microscopic examination.
OBJECTIVES
The objectives of this study were to evaluate and directly compare the microscopic appearance of silica and barium particles and various slide preparation techniques (e.g., use of coverslips, oil immersion, and different stains). A secondary objective of this study was to evaluate the effects of silica particles on cellular morphology after mechanical trauma with cytocentrifugation.
METHODS
Fluid samples (deionized water, pleural effusion, peritoneal effusion, cerebrospinal fluid, and urine) were collected and evaluated in silica- and non-silica-containing tubes. Barium was added to silica and non-silica samples. Direct and cytocentrifuge preparations were compared to evaluate the effect of silica particles on cellular morphology. Preparations were stained with Wright-Giemsa, rhodizonic acid disodium salt, Alizarin Red, Grocott's methenamine silver, and Prussian blue.
RESULTS
Silica and barium particles were identifiable via light microscopy with and without polarized light, although silica particles diminished with immersion oil. Barium particles retained their structure and diminished less under oil. Cytoseal mounting medium for coverslip placement resulted in diminished refractility of silica and some barium particles. Silica particles with mechanical interaction during cytocentrifugation resulted in disrupted cellular morphology with many lysed cells. Silica and barium particles were negative for all special stains tested.
CONCLUSIONS
Silica from plastic red top tubes adversely affects cell morphology in cytocentrifuge preparations, potentially affecting manual differential cell counts and compromising diagnostic interpretation. Samples intended for microscopic evaluation should not be collected in silica-containing tubes.
Topics: Animals; Barium; Silicon Dioxide; Specimen Handling; Pleural Effusion; Cytological Techniques
PubMed: 38097197
DOI: 10.1111/vcp.13288