Broad- and narrow-spectrum antibiotics: a different approach

Plastic Debris in the Aquatic Environment: An Emerging Substratum for Antimicrobial Resistant (AMR) Biofilms

Plastic pollution has quadrupled over the past years and has become a global concern due to its direct impact on life forms. The present study analysed whether the plastic debris in aquatic environments could act as the substratum for the antimicrobial-resistant (AMR) bacteria to form biofilm for survival. We have collected various plastic debris (n = 32) from six sites of the Periyar River, the drinking water source for the entire city and one of the most polluted rivers in Kerala (India). The chemical composition of plastics was screened via FTIR analysis and found that they comprised two types, viz., polyethylene and polypropylene. Bacteria isolated from the samples were screened for the AMR characteristics towards eight different classes of antibiotics. All isolates showed 100% resistance towards colistin and obtained the MAR index value of 0.1-0.4 range. Six representative bacterial isolates with high multiple antibiotic resistance (MAR) index were selected and identified by 16sRNA sequencing as Lysinibacillus mangiferihumi, Bacillus pumilus, Bacillus safensis, Bacillus cereus, Bacillus altitudins and Bacillus pumilus. In vitro biofilm formation was experimented on the purchased plastic samples in artificial media and river water using two selected strains, Bacillus pumilus and Bacillus cereus. Significant variations were observed in biofilm growth in different media (P < 0.05) regardless of plastic types (P > 0.05). The extracellular polymeric substances (EPS) and the characteristic holes on the surface morphology were visualized in SEM analysis, thus indicating the conditioning of the plastics by the isolates for biofilm formation.

Social and cultural determinants of antibiotics prescriptions: analysis from a public community health centre in North India

This paper explores the socio cultural and institutional determinants of irresponsible prescription and use of antibiotics which has implications for the rise and spread of antimicrobial resistance (AMR). This study describes the patterns of prescription of antibiotics in a public facility in India and identifies the underlying institutional, cultural and social determinants driving the irresponsible use of antibiotics. The analysis is based on an empirical investigation of patients' prescriptions that reach the in-house pharmacy following an outpatient department (OPD) encounter with the clinician. The prescription analysis describes the factors associated with use of broad-spectrum antibiotics, and a high percentage of prescriptions for dental outpatient department prescribed as a precautionary measure. This paper further highlights the need for future research insights in combining socio-cultural approach with medical rationalities, to further explore questions our analysis highlights like higher antibiotic prescription, etc., Along with the recommendations for further research.

Broad vs Narrow Spectrum Antibiotics in Common Bile Duct Stones: A Post Hoc Analysis of an Eastern Association for the Surgery of Trauma Multicenter Study

BACKGROUND

Antimicrobial guidance for common bile duct stones during the perioperative period is limited. We sought to examine the effect of broad-spectrum (BS) vs narrow-spectrum (NS) antibiotics on surgical site infections (SSIs) in patients with common bile duct stones undergoing same-admission cholecystectomy.

STUDY DESIGN

We performed a post hoc analysis of a prospective, observational, multicenter study of patients undergoing same-admission cholecystectomy for choledocholithiasis and/or acute biliary pancreatitis between 2016 and 2019. We excluded patients with cholangitis, perforated cholecystitis, and nonbiliary infections on admission. Patients were divided based on receipt of BS or NS antibiotics. Our primary outcome was the incidence of SSIs, and secondary outcomes included hospital length of stay, acute kidney injury (AKI), and 30-day readmission for SSI.

RESULTS

The cohort had 891 patients: 51.7% (n= 461) received BS antibiotics and 48.3% (n = 430) received NS antibiotics. Overall antibiotic duration was longer in the BS group than in the NS group (6 vs 4 d, p = 0.01); however, there was no difference in rates of SSI (0.9% vs 0.5%, p = 0.7) or 30-day readmission for SSI (1.1% vs 1.2%, p = 1.0). Hospital length of stay was significantly longer in the BS group (p < 0.001) as were rates of AKI (5% vs 1.4%, p = 0.001). On multivariable regression, BS antibiotic use was a risk factor for AKI (adjusted odds ratio 2.8, 95% CI 1.16 to 7.82, p = 0.02).

CONCLUSION

The incidence of SSI and 30-day readmission for SSI was similar between antibiotic groups. However, BS antibiotic use was associated with a longer hospitalization and greater likelihood of AKI.

Effects of restrictive-prescribing stewardship on antibiotic consumption in primary care in China: an interrupted time series analysis, 2012-2017

BACKGROUND

The overuse of antibiotics has been a major public health problem worldwide, especially in low- and middle- income countries (LMIC). However, there are few policies specific to antibiotic stewardship in primary care and their effectiveness are still unclear. A restrictive-prescribing stewardship targeting antibiotic use in primary care has been implemented since December 2014 in Hubei Province, China. This study aimed to evaluate the effects of the restrictive-prescribing stewardship on antibiotic consumption in primary care so as to provide evidence-based suggestions for prudent use of antibiotics.

METHODS

Monthly antibiotic consumption data were extracted from Hubei Medical Procurement Administrative Agency (HMPA) system from Sept 1, 2012, to Aug 31, 2017. Quality Indictors of European Surveillance of Antimicrobial Consumption (ESAC QIs) combined with Anatomical Therapeutic Chemical (ATC) classification codes and DDD per 1000 inhabitants per day (DID) methodology were applied to measure antibiotic consumption. An interrupted time series analysis was performed to evaluate the effects of restrictive-prescribing stewardship on antibiotic consumption.

RESULTS

Over the entire study period, a significant reduction (32.58% decrease) was observed in total antibiotic consumption, which declined immediately after intervention (coefficient = - 2.4518, P = 0.005) and showed a downward trend (coefficient = - 0.1193, P = 0.017). Specifically, the use of penicillins, cephalosporins and macrolides/lincosamides/streptogramins showed declined trends after intervention (coefficient = - 0.0553, P = 0.035; coefficient = - 0.0294, P = 0.037; coefficient = - 0.0182, P = 0.003, respectively). An immediate decline was also found in the contribution of β-lactamase-sensitive penicillins to total antibiotic use (coefficient = - 2.9126, P = 0.001). However, an immediate increase in the contribution of third and fourth-generation cephalosporins (coefficient = 5.0352, P = 0.005) and an ascending trend in the contribution of fluoroquinolones (coefficient = 0.0406, P = 0.037) were observed after intervention. The stewardship led to an immediate increase in the ratio between broad- and narrow-spectrum antibiotic use (coefficient = 1.8747, P = 0.001) though they both had a significant downward trend (coefficient = - 0.0423, P = 0.017; coefficient = - 0.0223, P = 0.006, respectively). An immediate decline (coefficient = - 1.9292, P = 0.002) and a downward trend (coefficient = - 0.0815, P = 0.018) were also found in the oral antibiotic use after intervention, but no significant changes were observed in the parenteral antibiotic use.

CONCLUSIONS

Restrictive-prescribing stewardship in primary care was effective in reducing total antibiotic consumption, especially the use of penicillins, cephalosporins and macrolides/lincosamides/streptogramins. However, the intervention effects were limited regarding the use of combinations of penicillins with ß-lactamase inhibitors, the third and fourth-generation cephalosporins, fluoroquinolones and parenteral antibiotics. Stronger administrative regulations focusing on specific targeted antibiotics, especially the use of broad-spectrum antibiotics and parenteral antibiotics, are in urgent need in the future.

Broad-Spectrum Antibiotic Treatment and Subsequent Childhood Type 1 Diabetes: A Nationwide Danish Cohort Study

Background

Studies link antibiotic treatment and delivery by cesarean section with increased risk of chronic diseases through changes of the gut-microbiota. We aimed to evaluate the association of broad-spectrum antibiotic treatment during the first two years of life with subsequent onset of childhood type 1 diabetes and the potential effect-modification by mode of delivery.

Materials and Methods

A Danish nationwide cohort study including all singletons born during 1997–2010. End of follow-up by December 2012. Four national registers provided information on antibiotic redemptions, outcome and confounders. Redemptions of antibiotic prescriptions during the first two years of life was classified into narrow-spectrum or broad-spectrum antibiotics. Children were followed from age two to fourteen, both inclusive. The risk of type 1 diabetes with onset before the age of 15 years was assessed by Cox regression. A total of 858,201 singletons contributed 5,906,069 person-years, during which 1,503 children developed type 1 diabetes.

Results

Redemption of broad-spectrum antibiotics during the first two years of life was associated with an increased rate of type 1 diabetes during the following 13 years of life (HR 1.13; 95% CI 1.02 to 1.25), however, the rate was modified by mode of delivery. Broad-spectrum antibiotics were associated with an increased rate of type 1 diabetes in children delivered by either intrapartum cesarean section (HR 1.70; 95% CI 1.15 to 2.51) or prelabor cesarean section (HR 1.63; 95% CI 1.11 to 2.39), but not in vaginally delivered children. Number needed to harm was 433 and 562, respectively. The association with broad-spectrum antibiotics was not modified by parity, genetic predisposition or maternal redemption of antibiotics during pregnancy or lactation.

Conclusions

Redemption of broad-spectrum antibiotics during infancy is associated with an increased risk of childhood type 1 diabetes in children delivered by cesarean section.

L,L-diaminopimelate aminotransferase (DapL): a putative target for the development of narrow-spectrum antibacterial compounds

Despite the urgent need for sustained development of novel antibacterial compounds to combat the drastic rise in antibiotic resistant and emerging bacterial infections, only a few clinically relevant antibacterial drugs have been recently developed. One of the bottlenecks impeding the development of novel antibacterial compounds is the identification of new enzymatic targets. The nutritionally essential amino acid anabolic pathways, for example lysine biosynthesis, provide an opportunity to explore the development of antibacterial compounds, since human genomes do not possess the genes necessary to synthesize these amino acids de novo. The diaminopimelate (DAP)/lysine (lys) anabolic pathways are attractive targets for antibacterial development since the penultimate lys precursor meso-DAP (m-DAP) is a cross-linking amino acid in the peptidoglycan (PG) cell wall of most Gram-negative bacteria and lys plays a similar role in the PG of most Gram-positive bacteria, in addition to its role as one of the 20 proteogenic amino acids. The L,L-diaminopimelate aminotransferase (DapL) pathway was recently identified as a novel variant of the DAP/lys anabolic pathways. The DapL pathway has been identified in the pathogenic bacteria belonging to the genus; Chlamydia, Leptospira, and Treponema. The dapL gene has been identified in the genomes of 381 or approximately 13% of the 2771 bacteria that have been sequenced, annotated and reposited in the NCBI database, as of May 23, 2014. The narrow distribution of the DapL pathway in the bacterial domain provides an opportunity for the development and or discovery of narrow spectrum antibacterial compounds.

Controlling methicillin-resistant Staphylococcus aureus by stepwise implementation of preventive strategies in a university hospital: impact of a link-nurse system on the basis of multidisciplinary approaches

BACKGROUND

Current approaches in the control of methicillin-resistant Staphylococcus aureus (MRSA) in the large tertiary referral hospital have not been universally successful.

METHODS

The trend of MRSA rates and their relationship with stepwise implementation of preventive strategies in Tokai University Hospital during a 76-month period from September 1998 to December 2004, was retrospectively analyzed with a quasi-experimental design.

RESULTS

Implementation of strategies including a feedback process with case and epidemic reporting, an infection control team and office, and a preventive guideline for MRSA did not result in reduction in monthly MRSA rates in the hospital, as analyzed with Shewhart u charts. When infection control link nurses were organized and their activities became full-scale, there appeared significant reduction in arithmetic mean of the monthly rates of MRSA from 6.3% to 5.0% in June 2002. Meanwhile the mean values for monthly counts of new MRSA cases also dropped in 15 of 25 wards/units in June 2002, as analyzed with Exponentially Weighted Moving Average charts. Concurrently, there was a significant increase (17.3%) in the monthly consumption of handwashing liquid plain soap. Thereafter the MRSA rates remained low for 2 years within three standard deviations.

CONCLUSIONS

The sustained reduction of MRSA rates in the hospital can be related to introduction of the infection control link-nurse system on the basis of continuous enforcement of basic and multidisciplinary approaches such as hand-hygiene compliance.

Methicillin-resistant Staphylococcus aureus in children with cystic fibrosis: An eradication protocol

A retrospective 12-year study (May 1988-July 2000) was undertaken in children with cystic fibrosis (CF) to evaluate 1) the magnitude of methicillin-resistant Staphylococcus aureus (MRSA) in these children; 2) the clinical impact of MRSA on CF; and 3) the efficacy of an MRSA protocol aimed at the eradication of the carrier state. The study maneuver comprised of 1) surveillance cultures of throat/rectum to detect the MRSA carrier state; 2) life-long cephradine rather than flucloxacillin to lift selection pressure; 3) topical application of oral and nebulized vancomycin for 5 days to clear the carriage of MRSA; and 4) a strict antistaphylococcal hygiene program, including handwashing and device policy. Fifteen children with CF (11 boys, with median age 117 months) positive for MRSA were enrolled. The current prevalence of MRSA among children with CF in our hospital is 6.5%. Of 15 children identified, only 12 (18 episodes of MRSA colonization) were treated according to protocol. Median age of MRSA acquisition was 73 months (interquartile range, 43-134 months). In 7 patients (55%), MRSA was eradicated. Of a total of 18 MRSA episodes, the protocol was successful in 10 episodes. The mean period of MRSA-free status was 12 months (range, 6-36 months). Pulmonary function (measured by FEV(1)) was not affected (68% of predicted before treatment, and 68% of predicted after treatment). All children were oropharyngeal carriers of both MRSA and ceftazidime-resistant P. aeruginosa. We believe that an effort has to be made to limit MRSA in CF clinics for the following reasons: 1) MRSA carriage in any individual is an abnormal condition; 2) limitation of systemic vancomycin use is desirable; 3) MRSA carriage may be a contraindication for lung transplantation; and 4) epidemiologically, a CF unit with a substantial MRSA problem functions as a source of dissemination for other patients.

Candidemia at a University Hospital: epidemiology, risk factors and predictors of mortality

BACKGROUND

Blood stream infection due to candida species are becoming increasingly important causes of morbidity and mortality in hospitalized patients. The aim of this study was to obtain epidemiological data on candidemia in patients at King Abdulaziz University Hospital (KAUH), and to discuss the influence of several clinical variables on the development and outcome of candidemia.

MATERIALS AND METHODS

Demographic information, risk factors, therapy and outcome of all patients who had candidemia at KAUH between January 1998 and December 1999 were reviewed.

RESULTS

Thirty-one candidemic episodes were identified. All the candidemic episodes were hospital acquired. The most common risk factors to candidemia were central venous catheters (87%), stay in intensive care unit (ICU) (77%), and broad-spectrum antibiotics therapy (74%). Candida albicans was the most frequently isolated species (71%), followed by candida tropicalis and candida parapsilosis (13% each). Twenty-six patients (84%) were treated with amphotericin B, 4 (13%) with fluconazole, and one (3%) with ketoconazole. Antifungal susceptibility testing of the isolates in general revealed minimal levels of resistance to amphotericin B (3%) versus 39% resistance to fluconazole. Less than 5% of Candida albicans were resistant to amphotericin B, in comparison with >35% of these strains that were resistant to fluconazole. The overall mortality was 71%. Mortality was significantly associated with the presence of central venous catheters (P=0.001), stay in intensive care unit (P<0.001), and prolonged hospital stay before the onset of candidemia (P=0.05).

CONCLUSION

Despite antifungal treatment, the mortality of candidemia is still high. Rapid changes in the rate of infection, potential risk factors, and emerging species demand continued and close surveillance of this serious infection.

Are most ICU infections really nosocomial? A prospective observational cohort study in mechanically ventilated patients

A prospective cohort study was undertaken with two end points: (i) to compare the 48 h time cut-off with the carrier state criterion for classifying infections, and (ii) to determine a time cut-off more in line with the carrier state concept. All patients admitted to the intensive care unit and expected to require mechanical ventilation for a period > or = 3 days were enrolled. Surveillance cultures of throat and rectum were obtained on admission and thereafter twice weekly to distinguish micro-organisms that were imported into the intensive care unit from those acquired during the stay in the unit. A total of 117 patients with median age of 61 years and median Simplified Acute Physiology Score II of 42, were included in the study. Of these patients, 48 (41%) developed a total of 74 infection episodes. Using the 48 h cut-off point, 80% of all infections were classified as ICU-acquired. According to the carrier state criterion, 44 infections (60%) were of primary endogenous development caused by micro-organisms imported into the intensive care unit. Seventeen secondary endogenous (23%) and 13 exogenous (17%) infections were caused by bacteria acquired in the unit. The carrier state classification allowed the transfer of 49% of infections from the ICU-acquired group into the import group. A time cut-off of nine days was found to identify ICU-acquired infections better than two days. These data suggest that monitoring of carriage of micro-organisms may be a more realistic approach to classify infections developing in the intensive care unit.