Low-dose Antibiotics Research Articles

Evaluation of Salmonella sp Contamination and its Antibiotics Resistance Patterns Isolated from Broiler Meat Sold at Wet Market in Center of Surabaya

Antibiotic resistance now days become a main issue to the medical researches as found many positive result of antibiotic resistance test. One of the causes of antibiotic resistance is using antibiotic as a feed additive to animal. Bacteria that are resistant to antibiotics can be a danger to humans, in this case the resistant bacteria as a result of treatment errors animals, especially chickens that uses low-dose antibiotics as growth promoters. This study aimed to determine the contamination of Salmonella sp and its antibiotics resistance patterns of Salmonella sp isolated from broiler meat sold at wet market in the Center of Surabaya: (a) Pasar Kembang, (b) Pasar Kupang, (c) Pasar Dukuh Kupang, (d) Pasar Kedungsari, (e) Pasar Kedungdoro and (f) Pasar Keputran. The method that used in this study was bacteriological isolation and identification method. The method started with pre-enrichment using Buffered Pepton Water, selective enrichment using Tetrathionate Broth and Selenite Cysteine broth, selective media using Salmonella-Shigella Agar, Biochemical test using Triple Sugar Iron Agar, Simon Citrate, Methyl Red – Voges Proskauer, and Sulfide Indol Motility, and followed with susceptibility test according to Kirby-Bauer method using Mueller-Hinton Agar. The antibiotics that used in susceptibility test were: (a) Meropenem, (b) Ampicillin Sulbactam, (c) Amikacin, (d) Ofloxacin and (e) Nalidixic Acid. The results of this study were found 90% or 27 of 30 samples positive contaminated with Salmonella sp. The results of antibiotics resistance from 27 isolates 0% were resistant to Meropenem, 0% were resistant to Amikacin; 3.7% were resistant to Ampicillin-Sulbactam; 11.1% were resistant to Ofloxacin and 44.4% were resistant to Nalidixic Acid.

A surface acoustic wave biofilm sensor integrated with a treatment method based on the bioelectric effect

Bacterial biofilms have an extensive impact on quality of life, ranging from severe infections in the clinical field to water facility contamination in environmental science. Biofilms are comprised of diverse bacteria that produce an extracellular matrix which prevents drug diffusion through them. Hence traditional antibiotic therapies require 500–5000 times the concentration used to eliminate non-biofilm-associated infections. Early biofilm detection is critical for effective eradication. Moreover, developing an alternative biofilm treatment method that utilizes low doses of antibiotics is desired. In this paper, a real-time microsystem is shown to detect growth of biofilms as well as their removal through integrated treatment. Detection of biofilms is achieved using a surface acoustic wave (SAW) sensor that monitors the total biomass by measuring the resonant frequency of the system. Biofilm treatment is based on the bioelectric effect (BE), a combination of low-dose antibiotics with application of both alternating and direct current signals. The detection limit of the SAW system is approximately 166pg, corresponding to a bacterial population on the order of hundreds of bacteria. The system is used to observe an 80% reduction of total biomass when treated by the BE as compared to traditional antibiotics. Through system integration of the BE with the SAW sensor, simultaneous biofilm detection and treatment is achieved. The system consumes 194μW of power, with the sensor and treatment consuming 100μW and 94μW, respectively. The integrated sensing and treatment capabilities of this system advance the development of an innovative biofilm control method.

The Role of Direct-Fed Microbials in Conventional Livestock Production.

Supplementation of direct-fed microbials (DFM) as a means to improve the health and performance of livestock has generated significant interest over the past 15+ years. A driving force for this increased interest in DFM is to reduce or eliminate the use of low-dose antibiotics in livestock production. This increased attention toward DFM supplementation has generated an extensive body of research. This effort has resulted in conflicting reports. Although there has been considerable variation in the design of these studies, one of the main causes for this lack of consistency may be attributed to the variation in the experimental immune challenge incorporated to evaluate DFM supplementation. Taking into account the experimental immune challenge, there is strong evidence to suggest that DFM supplementation may have an impact on the immune response, overall health, and performance of livestock.

Temporal Relationships Exist Between Cecum, Ileum, and Litter Bacterial Microbiomes in a Commercial Turkey Flock, and Subtherapeutic Penicillin Treatment Impacts Ileum Bacterial Community Establishment

Gut health is paramount for commercial poultry production, and improved methods to assess gut health are critically needed to better understand how the avian gastrointestinal tract matures over time. One important aspect of gut health is the totality of bacterial populations inhabiting different sites of the avian gastrointestinal tract, and associations of these populations with the poultry farm environment, since these bacteria are thought to drive metabolism and prime the developing host immune system. In this study, a single flock of commercial turkeys was followed over the course of 12 weeks to examine bacterial microbiome inhabiting the ceca, ileum, and corresponding poultry litter. Furthermore, the effects of low-dose, growth-promoting penicillin treatment (50 g/ton) in feed on the ileum bacterial microbiome were also examined during the early brood period. The cecum and ileum bacterial communities of turkeys were distinct, yet shifted in parallel to one another over time during bird maturation. Corresponding poultry litter was also distinct yet more closely represented the ileal bacterial populations than cecal bacterial populations, and also changed parallel to ileum bacterial populations over time. Penicillin applied at low dose in feed significantly enhanced early weight gain in commercial poults, and this correlated with predictable shifts in the ileum bacterial populations in control versus treatment groups. Overall, this study identified the dynamics of the turkey gastrointestinal microbiome during development, correlations between bacterial populations in the gastrointestinal tract and the litter environment, and the impact of low-dose penicillin on modulation of bacterial communities in the ileum. Such modulations provide a target for alternatives to low-dose antibiotics.

An assessment of clinicians’ and patients’ experiences in the management of bladder pain syndrome

Current management of bladder pain syndrome (BPS) was evaluated through a prospective electronic questionnaire posted on three patient support groups and sent to all members on the British Society of Urogynaecology (BSUG) database. Methods of diagnosis and treatment were assessed. 133 patients and 69 clinicians participated in the survey. Patients reported their main symptom to be pain when their bladder was full in 80% (n = 107) and the most bothersome symptom was pelvic pain (22%, n = 29). 93% (n = 64) of clinicians made their diagnosis by history and cystoscopy. 78% (n = 54) of clinicians treated patients with amitriptyline and 75% (n = 52) by dietary modification while 77% (n = 102) of patients reported using simple analgesia, 74% (n = 98) dietary modification and 62% (n = 83) low-dose long-term antibiotics. There is wide variation in diagnostic methods and treatments of BPS used by clinicians and experienced by patients with no obvious consensus. National guidance is needed to help standardise care.

Downsides of low-dose antibiotics

Downsides of low-dose antibiotics

Subinhibitory antibiotic therapy alters recurrent urinary tract infection pathogenesis through modulation of bacterial virulence and host immunity.

ABSTRACTThe capacity of subinhibitory levels of antibiotics to modulate bacterial virulence in vitro has recently been brought to light, raising concerns over the appropriateness of low-dose therapies, including antibiotic prophylaxis for recurrent urinary tract infection management. However, the mechanisms involved and their relevance in influencing pathogenesis have not been investigated. We characterized the ability of antibiotics to modulate virulence in the uropathogens Staphylococcus saprophyticus and Escherichia coli. Several antibiotics were able to induce the expression of adhesins critical to urothelial colonization, resulting in increased biofilm formation, colonization of murine bladders and kidneys, and promotion of intracellular niche formation. Mice receiving subinhibitory ciprofloxacin treatment were also more susceptible to severe infections and frequent recurrences. A ciprofloxacin prophylaxis model revealed this strategy to be ineffective in reducing recurrences and worsened infection by creating larger intracellular reservoirs at higher frequencies. Our study indicates that certain agents used for antibiotic prophylaxis have the potential to complicate infections.

The Boston keratoprosthesis 2014: a step in the evolution of artificial corneas

“Artificial corneas” have been attempted in severe corneal disease for at least 230 years, with largely disappointing results until recently. ‘The Boston Keratoprosthesis’ (B-Kpro) has been part of this history on and off for a half century. Developed from several previously known concepts, it was originally made of PMMA plastics in a collar button design (Type I), to be implanted into a corneal graft carrier and then transplanted to the patients’ cornea. (A Type II with an additional stem for lid penetration is occasionally used in end-stage dry eyes.) Management and device changes have over the years led to marked clinical improvements. Thus, postoperative infections have been drastically reduced by using low-dose prophylactic antibiotics. The corneal surface has been found to be well protected from evaporative damage by a soft contact lens or a conjunctional flap. Postoperative tissue melt around the device has been markedly reduced by improvement of nutrition from the aqueous (perforated back plates) and better anti-inflammatory strategies. Titanium alloys can be used for non-transparent parts to reduce inflammation and increase biointegration. Retroprosthesis membranes and retina complications have similarly been markedly reduced. However, post-operative glaucoma is still a stubborn problem that can cause long-term attrition of vision. Autoimmune diseases are particularly treacherous and B-KPros should not at present be used routinely. About 12,000 Boston Keratoprostheses have so far been distributed world-wide. Robust research is presently on-going to improve long-term safety, especially for the developing world.

Prophylaxe rezidivierender Harnwegsinfektionen

Recurrent urinary tract infections (rUTI), defined as ≥ 3 UTIs per year, mostly affect young and postmenopausal women. Treatable predisposing factors are rare. General recommendations to reduce rUTIs lower the recurrence rate by up to approximately two thirds. Continuous long-term prophylaxis (LP) with low dose antibiotics or single postcoital doses can reduce the recurrence rate of rUTIs to as low as 5%. According to the European Association of Urology guidelines nitrofurantoin, trimethoprim and co-trimoxazole are the first-line drugs and cephalosporins or fluoroquinolones should be restricted to specific indications. Oral and parenteral immunotherapy were found to be effective in several controlled studies for prevention of rUTIs and can be combined with acute antibiotic therapy. Vaginal prophylaxis with estriol has proven its positive effect without serious gynecological side effects and there is also increasing evidence that cranberries prevent rUTIs but the exact mode of this therapy remains to be defined. There are also other promising modalities, such as phytotherapeutics, mannose, urine acidification, influencing bacterial intestinal and vaginal flora and the general immune response by e.g. acupuncture and inpatient rehabilitation, the therapeutic value of which still has to be proven.

Low-dose antibiotics: current status and outlook for the future.

Low-dose antibiotics: current status and outlook for the future.

Antibiotic prophylaxis in the management of vesicoureteric reflux: a randomized double-blind placebo-controlled trial.

The benefits of long-term low-dose antibiotics in preventing urinary tract infection (UTI) and renal damage in children with primary vesicoureteric reflux (VUR) are unclear. Children aged between 1 and 12years with VUR grade I-IV and a microbiologically proven UTI were randomized into two groups to receive either antibiotic prophylaxis [2mg/kg trimethoprim + sulfamethoxazole (TMP-SMX)] daily or placebo, respectively, for 12months. Primary outcome was microbiologically confirmed symptomatic UTI. Intention-to-treat analysis using time-to-event data was performed. A total of 93 children (66.7% boys) with a median age of 4.6years were enrolled in this study; VUR grade III-IV was present in 73.1% of these children. At least one symptomatic UTI occurred in ten (21.3%) patients receiving antibiotic prophylaxis and in three (6.5%) patients receiving placebo [hazard ratio in antibiotic group 3.9; 95% confidence interval (CI) 1- 14; log rank test P = 0.02). Compared to the group receiving placebo, the antibiotic group had a 14.8 % increased risk for developing UTI (95% CI 1-28; P = 0.03). Of the total number of episodes of UTI, 58.3% of those in the antibiotic group were caused by TMP-SMX-resistant bacteria compared to 20% in the placebo group (P = 0.15). A renal scan at 12 months revealed that six of 37 (16.2%) patients in the antibiotic group and seven of 43 (16.3%) patients in the placebo group had new or worsening of pre-existing scar. Long-term antibiotic prophylaxis with TMP-SMX is associated with increased risk of symptomatic UTI compared to placebo in children with grade I-IV VUR.

Genomic interplay in bacterial communities: implications for growth promoting practices in animal husbandry.

The discovery of antibiotics heralded the start of a “Golden Age” in the history of medicine. Over the years, the use of antibiotics extended beyond medical practice into animal husbandry, aquaculture and agriculture. Now, however, we face the worldwide threat of diseases caused by pathogenic bacteria that are resistant to all existing major classes of antibiotic, reflecting the possibility of an end to the antibiotic era. The seriousness of the threat is underscored by the severely limited production of new classes of antibiotics. Evolution of bacteria resistant to multiple antibiotics results from the inherent genetic capability that bacteria have to adapt rapidly to changing environmental conditions. Consequently, under antibiotic selection pressures, bacteria have acquired resistance to all classes of antibiotics, sometimes very shortly after their introduction. Arguably, the evolution and rapid dissemination of multiple drug resistant genes en-masse across microbial pathogens is one of the most serious threats to human health. In this context, effective surveillance strategies to track the development of resistance to multiple antibiotics are vital to managing global infection control. These surveillance strategies are necessary for not only human health but also for animal health, aquaculture and plant production. Shortfalls in the present surveillance strategies need to be identified. Raising awareness of the genetic events that promote co-selection of resistance to multiple antimicrobials is an important prerequisite to the design and implementation of molecular surveillance strategies. In this review we will discuss how lateral gene transfer (LGT), driven by the use of low-dose antibiotics in animal husbandry, has likely played a significant role in the evolution of multiple drug resistance (MDR) in Gram-negative bacteria and has complicated molecular surveillance strategies adopted for predicting imminent resistance threats.

Antibiotics promote aggregation within aquatic bacterial communities.

The release of antibiotics (AB) into the environment poses several threats for human health due to potential development of AB-resistant natural bacteria. Even though the use of low-dose antibiotics has been promoted in health care and farming, significant amounts of AB are observed in aquatic environments. Knowledge on the impact of AB on natural bacterial communities is missing both in terms of spread and evolution of resistance mechanisms, and of modifications of community composition and productivity. New approaches are required to study the response of microbial communities rather than individual resistance genes. In this study a chemostat-based experiment with 4 coexisting bacterial strains has been performed to mimicking the response of a freshwater bacterial community to the presence of antibiotics in low and high doses. Bacterial abundance rapidly decreased by 75% in the presence of AB, independently of their concentration, and remained constant until the end of the experiment. The bacterial community was mainly dominated by Aeromonas hydrophila and Brevundimonas intermedia while the other two strains, Micrococcus luteus and Rhodococcus sp. never exceed 10%. Interestingly, the bacterial strains, which were isolated at the end of the experiment, were not AB-resistant, while reassembled communities composed of the 4 strains, isolated from treatments under AB stress, significantly raised their performance (growth rate, abundance) in the presence of AB compared to the communities reassembled with strains isolated from the treatment without AB. By investigating the phenotypic adaptations of the communities subjected to the different treatments, we found that the presence of AB significantly increased co-aggregation by 5–6 fold. These results represent the first observation of co-aggregation as a successful strategy of AB resistance based on phenotype in aquatic bacterial communities, and can represent a fundamental step in the understanding of the effects of AB in aquatic ecosystems.

Efficacy and Pharmacological Mechanism of Pronase-Enhanced Low-Dose Antibiotics for Helicobacter pylori Eradication

This study examined the efficacy and pharmacological mechanism of pronase-assisted low-dose antibiotics for eradication of Helicobacter pylori. Mongolian gerbils infected with H. pylori received 7-day treatment (omeprazole, different concentrations of pronase, amoxicillin, and clarithromycin), and the efficacy was assessed using the eradication rate and the colonization of H. pylori. In Mongolian gerbils orally administered pronase, the thickness of the gastric mucous layer (GML) was examined using immunohistochemical and alcian blue staining, and the concentrations of amoxicillin in gastric tissue and serum were detected using high-performance liquid chromatography (HPLC). The eradication rates were 80.0% (12/15) in the high-pronase quadruple group (HPQG) and 86.7% (13/15) in the high-antibiotic group (HAG) (P = 1.000). The antibiotic dose in the HPQG was only 1/20 that in the HAG. Thirty minutes after oral treatment with pronase, the sticky protein of the GML was hydrolyzed, and the GML became thinner. Higher amoxicillin concentrations in both the gastric tissue and serum were observed in the pronase group than in the Am10 group. The concentration of amoxicillin in the Am10-plus-Pr108 group in gastric tissue was 3.8 times higher than in the Am10 group in 5 min. Together, these data suggest that pronase significantly reduced the dose of antibiotics used in H. pylori eradication. The pharmacological mechanism is likely pronase removal of the mucus layer, promoting chemical factor (i.e., gastric acid and pepsinogen) distribution and increasing the antibiotic concentrations in the deep GML, which acted on H. pylori collectively. Thus, pronase may enhance the level of antibiotics for eradication of H. pylori in the clinic.

Potion or Poison? Cranberry products

SUMMARY MESSAGE: Although there is some evidence to suggest that cranberry protects against urinary tract infections, the literature is conflicting and strong scientific validation is missing. There is, however, minimal risk in the consumption of cranberry products and they may be a suitable alternative to low-dose antibiotics in urinary tract infection prophylaxis.

Strategies to reduce the use of antibiotics in animals

Imagine a farm with over 100,000 head of cattle, each one receiving daily low-dose antibiotics in their food or water, not to treat illness, but to make them put on weight faster. In the United States, the total amount of antibiotics used in food-producing animals rose by 16% between 2009 and 2012, to 14.61 million […]

Comparison of microbial communities in sequencing batch reactors (SBRs) exposed to trace erythromycin and erythromycin-H2O

Wastewater treatment plants (WWTPs) are major collection pools of antibiotics of which low concentrations may induce antibiotic resistance in their microbial communities and pose threat to human health. However, information is still limited on the microbial community alteration in WWTPs upon exposure to low-dose antibiotics due to absence of negative control systems without input of resistant bacteria and resistance genes. Here we report the impact of trace erythromycin (ERY) and dehydrated erythromycin (ERY-H2O) on microbial community dynamics in three long-term (1 year) running sequencing batch reactors (SBRs), R1 (ERY-H2O), R2 (ERY), and negative control R3. The PhyloChip microarray analysis showed that ERY-H2O and ERY significantly altered their microbial communities based on bacterial richness (e.g., 825 operational taxonomic units (OTUs) in R1, 699 OTUs in R2, and 920 OTUs in R3) and population abundance (15 and 48 subfamilies with >80 % abundance decrease in R1 and R2, respectively). ERY-H2O and ERY have broad but distinct antimicrobial spectrums. For example, bacteria of all the major phyla (i.e., Proteobacteria, Actinobacteria, Bacteroidetes, and Chloroflexi) present in SBRs were severely inhibited by ERY-H2O and ERY, but bacteria of Acidobacteria, Chlorobi, Firmicutes, Nitrospira and OP10 phyla were only inhibited by ERY. Very limited bacterial groups showed antibiotic resistance to ERY-H2O or ERY through forming biofilms (e.g., Zoogloea) or synthesizing resistant proteins (e.g., Thauera, Candidatus Accumulibacter, Candidatus Competibacter, and Dechloromonas) in the SBRs. Inhibition was observed to be the main effect of ERY-H2O and ERY on microbial communities in the reactors. The results would broaden our knowledge of effects of low-dose antibiotics on microbial communities in WWTPs.

English

Introduction As obstetricians, gynaecologists and urogynaecologists, anecdotally, we routinely see patients who complain of symptoms of urinary tract infections but have repeated clean catch urinary specimen remaining sterile, yet they respond positively to a short course of antibiotics. Sometimes, the response is sustained, on other occasions, the response is short-lived, but the response is usually satisfying to the patient. Surely, this cannot simply be the result of the known placebo effect. This paper makes a case for lowdose broad spectrum oral antibiotics in a pregnant patient with recurrent urethral pain syndrome. Case report We performed an extensive English language electronic search in the following databases: Medline, Embasse, Amed, Cinahl, Pubmed, Cochrane library and Trip; and did some search using the following search terms: urethral syndrome, urethral diseases in pregnancy, urologic diseases aetiology, presentation, treatment, outcome and therapeutics from 1951 to 2012. We found a paper by Baerheim and colleagues, who observed that there is equal symptomatic outcome after antibacterial treatment of acute lower urinary tract infection and the acute urethral syndrome in adult women. Their work did not include pregnant patients. Emboldened by the strength of the findings by Baerheim et al. and our observations in a case of a 24-yearold gravid female with recurrent episodes of urethral syndrome, which subsided when she was placed on low-dose oral co-amoxiclav, but rebounded leading to urinary retention when the antibiotic was discontinued; we make a case for low-dose oral antibiotics in a pregnant patient with recurrent urethral syndrome. Conclusion Since this is only a case report, it restricts us from making generalised statements, we would suggest that consideration be given to the use of broad-based antibiotics excreted by the kidneys in pregnant patients presenting with the urethral pain syndrome.

National burden of antibiotic use for adult rhinosinusitis

National burden of antibiotic use for adult rhinosinusitis

Induction of MRSA Biofilm by Low-Dose β-Lactam Antibiotics: Specificity, Prevalence and Dose-Response Effects

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of hospital- and community-associated infections. The formation of adherent clusters of cells known as biofilms is an important virulence factor in MRSA pathogenesis. Previous studies showed that subminimal inhibitory (sub-MIC) concentrations of methicillin induce biofilm formation in the community-associated MRSA strain LAC. In this study we measured the ability sub-MIC concentrations of eight other β-lactam antibiotics and six non-β-lactam antibiotics to induce LAC biofilm. All eight β-lactam antibiotics, but none of the non-β-lactam antibiotics, induced LAC biofilm. The dose-response effects of the eight β-lactam antibiotics on LAC biofilm varied from biphasic and bimodal to near-linear. We also found that sub-MIC methicillin induced biofilm in 33 out of 39 additional MRSA clinical isolates, which also exhibited biphasic, bimodal and linear dose-response curves. The amount of biofilm formation induced by sub-MIC methicillin was inversely proportional to the susceptibility of each strain to methicillin. Our results demonstrate that induction of biofilm by sub-MIC antibiotics is a common phenotype among MRSA clinical strains and is specific for β-lactam antibiotics. These findings may have relevance to the use of β-lactam antibiotics in clinical and agricultural settings.