Rate Of Bacterial Infections Research Articles

Bacterial Conjunctivitis: An Updated Review for Healthcare Professionals

Bacterial conjunctivitis, commonly known as "pink eye," is a prevalent ocular condition often diagnosed in primary healthcare settings. It is caused by bacterial infections, presenting symptoms like redness, itching, and discharge. While viral and allergic conjunctivitis are more common, bacterial conjunctivitis can lead to severe complications if left untreated. This review explores bacterial conjunctivitis' etiology, epidemiology, pathophysiology, diagnosis, treatment, and complications, offering healthcare professionals insights for accurate management and diagnosis.The aim of this review is to update healthcare professionals on bacterial conjunctivitis, focusing on its causes, epidemiology, clinical features, diagnostic methods, and management strategies.This article synthesizes existing research on bacterial conjunctivitis, drawing from a range of sources to provide comprehensive insights into its transmission, pathogenesis, and the clinical approach to diagnosis and treatment. The review also examines bacterial pathogens, diagnostic tools, and antibiotic resistance patterns.Bacterial conjunctivitis is most commonly caused by Haemophilus influenzae, Streptococcus pneumoniae, and Staphylococcus aureus. In children, it is often linked to otitis media, while adults may experience more frequent cases of Staphylococcus aureus. The condition is diagnosed through clinical presentation, with occasional reliance on culture and PCR testing for complicated cases. Antibiotic treatment, particularly with topical agents, is effective in most cases, although overuse remains a concern. Empiric antibiotic therapy is often prescribed despite a relatively low bacterial infection rate in pediatric cases.Bacterial conjunctivitis is a common, treatable condition with a generally favorable prognosis. However, misdiagnosis and unnecessary antibiotic use contribute to the growing problem of antimicrobial resistance. Clinicians should adopt diagnostic approaches to minimize unnecessary prescriptions and enhance treatment efficacy.

Complex antibacterial action of enzymes acting on Staphylococcus aureus biofilms

The widespread use of antibiotics in medicine and agriculture has significantly accelerated the emergence rate of bacterial infections showing multiple antibiotic resistance. Since resistance to conventional antibiotics is developed rather quickly, designing alternative antimicrobial drugs with other mechanisms underlying their effects on bacteria is a promising. The enzymes possessing bactericidal activity may be one option for such antibacterial agents. The study aimed to produce the combination recombinant protein-based products active against bacteria and their biofilms. Soluble forms of five recombinant proteins were produced using the genetic engineering approaches. Two of these have a bacteriolytic effect (endolysins LysK and PM9 from the Staphylococcus aureus bacteriophages), the other are capable of disrupting extracellular DNA matrix in biofilms (two nonspecific nucleases NucA, as well as the DNA-specific deoxyribonuclease I). It has been shown that natural endolysin PM9 with the truncated catalytic domain shows 4 times lower bacteriolytic efficacy compared to the full-size LysK version. Comparative analysis revealed 1.5–2 timed higher efficacy of nonspecific nucleases in terms of bacterial biofilm disruption compared to the DNA-specific deoxyribonuclease I. It has been shown that simultaneous use of endolysins and nucleases has a synergistic antibacterial effect and disrupts biofilms of the pathogenic bacterium Staphylococcus aureus. The findings show the prospects of developing the recombinant protein-based antibacterial drugs.

Thrombosis and Encapsulated Bacterial Infection Rates in Patients with Paroxysmal Nocturnal Hemoglobinuria Who Received Pegcetacoplan: Nearly 3 Years of Post-Marketing Experience

Thrombosis and Encapsulated Bacterial Infection Rates in Patients with Paroxysmal Nocturnal Hemoglobinuria Who Received Pegcetacoplan: Nearly 3 Years of Post-Marketing Experience

Epidemiology of Infections in Lung Transplant Recipients Treated With Belatacept.

Belatacept is a costimulatory blocker that can be used to prevent and treat rejection in lung transplant recipients (LuTRs). The epidemiology of infections in belatacept-treated LuTRs has not been systematically evaluated. We performed a single-center retrospective study of all adult LuTRs who received belatacept as prevention or treatment of antibody-mediated rejection (desensitization) or as part of maintenance immunosuppression from January 1, 2011, to June 30, 2022. We assessed the epidemiology of infections that occurred within 12 months following the first belatacept dose. Fifty-two LuTRs received at least one dose of belatacept as either desensitization (n = 32) or maintenance immunosuppression (n = 20). Among 45 patients who were cytomegalovirus (CMV) donor and/or recipient seropositive, nine (20%) developed CMV infection. Seven (77%) CMV infections occurred despite valganciclovir prophylaxis and four (44%) were associated with antiviral resistance. Three (6%) LuTRs developed Epstein-Barr virus (EBV) associated post-transplant lymphoproliferative disorder (PTLD). Twenty-five (48%) LuTRs developed 43 bacterial infections and five (10%) developed proven or probable invasive fungal disease. Incidence rates of viral, bacterial, and fungal infections were similar between the desensitization and maintenance groups: incidence rate ratios (95% confidence interval) were 0.70 (0.32-1.57), 1.31 (0.70-2.46), and 2.82 (0.31-25.2), respectively. Infection/PTLD prompted belatacept discontinuation in eight (15%) patients. In the first year after belatacept initiation, LuTRs commonly developed CMV infections, EBV+ PTLD, and bacterial infections. Multicenter collaborations are needed to better understand infection risks in LuTRs treated with belatacept.

Human body resistance dynamics in the post-covid period

The issue of the state of specific and nonspecific resistance in the post-COVID period and the possible consequences of COVID-19 remains poorly understood. A clinical and laboratory examination of 124 patients was conducted at various time points after COVID-19 infection. 62 patients recovered completely and 62 had post-COVID syndrome. The leukocyte count and leukogram were evaluated in all patients. Immunogram parameters were additionally evaluated in patients with post-COVID syndrome. The results showed that, regardless of post-COVID syndrome, leukocyte count is lower in all patients within six months after COVID-19 infection than in unaffected subjects. The absolute neutrophil count is restored only 12 months later. In the presence of post-COVID syndrome, the absolute number of CD3+, CD4+and CD19+lymphocytes was lower than in healthy people. At the same time, 3 to 15 months after that, IgA titer in patients with PCS was significantly lower and that of for total IgM and IgG was higher without any clinical or laboratory signs of inflammation. The total blood IgE level was significantly higher and increased by the end of the observation period. A decreased activity of nonspecific protection, as well as indicators of cellular and humoral immunity in patients with post-COVID syndrome is accompanied by higher rate of viral and bacterial infections of various localization. Whereas during the first period an increase in total blood ID is not accompanied by clinical signs of atopy, then 6 months later the frequency of allergy increases. During the same period, cases of a joint syndrome revealed as arthralgia or progressive joint destruction become more frequent. Atopic manifestations are often combined with joint syndrome. Thus, after a COVID-19 infection, a low long-term level of nonspecific protection remains in vivo. In patients with post-COVID syndrome, low nonspecific and specific body resistance is manifested by viral and bacterial infections of the mucous membranes and skin. An imbalance in the immune system contributes to developing allergic and autoimmune processes.

Hypoxic culture enhances the antimicrobial activity of amnion-derived mesenchymal stem cells, thereby reducing bacterial load and promoting wound healing in diabetic mice

BackgroundConditioned medium from amnion-derived mesenchymal stem cells (AMSCs) enhances wound healing, a process that is further improved under hypoxic culture conditions. Diabetic foot ulcers are difficult to treat and are frequently complicated by a high rate of bacterial infections, mainly Staphylococcus aureus, which can lead to limb amputation and death. Here, we topically applied conditioned medium from AMSCs cultured under hypoxic conditions to S. aureus-infected wounds in diabetic mice to investigate its effect on bacterial counts and wound healing. MethodsWe prepared conditioned medium by culturing AMSCs under 21 % or 1 % O2 and investigated its effects on S. aureus. We infected skin wounds of diabetic mice with S. aureus and treated these with hydrogels containing the conditioned medium to examine its effect on bacterial inhibition and wound healing. ResultsConditioned medium from AMSCs cultured under 1 % O2 contained higher levels of the antimicrobial peptide LL-37. It significantly inhibited S. aureus growth in vitro, reduced bacterial counts in infected wounds, and facilitated wound closure in diabetic mice. ConclusionsHydrogels containing conditioned medium from hypoxically cultured AMSCs inhibited the growth of S. aureus and promoted wound healing in a mouse model of diabetic wounds.

The rs6967330 minor allele in CDHR3 is a significant risk factor for severe acute exacerbations in chronic rhinosinusitis

Acute exacerbations of chronic rhinosinusitis (AECRS) are commonly triggered by rhinovirus (RV) infections with secondary bacterial infections. Risk factors for AECRS are not well understood. To determine if carriers of the minor allele rs6967330 (AA/AG) in the Cadherin related family member 3 (CDHR3) gene have an increased risk for RV infections in AECRS in vivo and identify CDHR3 genotype-dependent host responses to RV infection in differentiated nasal airway liquid interface (ALI) cultures ex vivo. We performed a prospective year-long study of adult subjects with chronic rhinosinusitis (CRS) by rs6967330 genotype (AA/AG, n=16; GG, n=38). We contacted subjects every 2 weeks, and if they reported AECRS clinical data were collected. ALI cultures of adults with CRS (AG/AA,n=19; GG,n=19) were challenged with RV-A and RV-C. We measured viral copy numbers at 4- and 48-hours post-infection and RNA transcriptomes and cytokines at 48 hours post infection. Subjects with the minor allele had significantly higher rates of RV and bacterial infections than those with the major allele. ALI minor allele cultures had higher viral copy numbers of RV-A and RV-C after 48 hours compared to the major allele. Differentially expressed genes (DEG) and pathways identified an upregulation of IL-10 and IL4/13 pathways and a significant downregulation of toll like receptor (TLR) pathways in the minor allele cultures after RV-A and RV-C infection. Unsupervised hierarchical analysis of all DEGs suggest that allergic rhinitis had an additive effect on this response. The rs6967330 minor allele is associated with increased RV-A and RV-C replication, downregulation of TLR-mediated responses and increased T2-type and cytokine and chemokine responses during RV infection.

A Study of the Characteristics and Properties of P. aeruginosa Isolated from Different Sources and their Resistance to Antibiotics

Pseudomonas aeruginosa, a common opportunistic bacterium, is a major source of human surface infections. Infections with these bacteria are difficult to cure and cause significant economic implications. Objectives The current study looked at the antibiotic resistance patterns of P. aeruginosa isolated from burns, wound swabs, and urinary tract infections that were referred to Iraq Hospitals' emergency health care units. From October 2022 to May 2023, 180 swabs were collected from burn and wound patients (110 burns, 67 wounds, and 3 urinary tract infections) of both sexes, (80) males and (100) females, aged 1-72 years, at Baghdad government hospitals: Ghazi Al-Hariri Hospital, Central Laboratories, Specialized Burns Hospital, and Yarmouk Hospital. Results:(180) diagnostic swabs from patients with burns and wound infections of both sexes, (80) males and (100) females, aged 1–72 years. The current study found 25(31.25) more P. aeruginosa positive cases in males than females, with 29(29) out of 54 positive cases. The study discovered that the age group 21-30 years had the highest rate of bacterial infection, followed by the age groups 11-20 and 1-10, with 11 (20.37%), 10 (18.51%), and 10 (18.51%), respectively. According to the current study's findings, the antibiotics Amikacin, Gentamicin, Ceftazidime, Cefepime, Netilmicin, and Tobramycin showed the highest resistance rates (81.4%, 81.4%, 79.6%, 72.2%, 74%, and 79.6%, respectively).The test findings showed that 52 isolates (96%) produced pyrocyanin and hemolysins. Bacterial colonies were white to gray with a sticky feel. All isolates exhibited β-hemolysis.Alkaline protease production All isolates exhibited a translucent halo surrounding the bacterial colonies.Lipase production All isolates exhibited a hazy halo surrounding the development zone of P.aeruginosa colonies. The current study discovered that the antibiotics Amikacin, Gentamicin, Ceftazidime, Cefepime, Netilmicin, and Tobramycin were the most resistant in cases of burn and wound patients, as well as urinary tract infections in Iraq.

A retrospective propensity-score-matched cohort study of the impact of procalcitonin testing on antibiotic use in hospitalized patients during the first wave of COVID-19.

Procalcitonin (PCT) is a blood marker used to help diagnose bacterial infections and guide antibiotic treatment. PCT testing was widely used/adopted during the COVID-19 pandemic in the UK. Primary: to measure the difference in length of early (during first 7 days) antibiotic prescribing between patients with COVID-19 who did/did not have baseline PCT testing during the first wave of the pandemic. Secondary: to measure differences in length of hospital/ICU stay, mortality, total days of antibiotic prescribing and resistant bacterial infections between these groups. Multi-centre, retrospective, observational, cohort study using patient-level clinical data from acute hospital Trusts/Health Boards in England/Wales. Inclusion: patients ≥16 years, admitted to participating Trusts/Health Boards and with a confirmed positive COVID-19 test between 1 February 2020 and 30 June 2020. Data from 5960 patients were analysed: 1548 (26.0%) had a baseline PCT test and 4412 (74.0%) did not. Using propensity-score matching, baseline PCT testing was associated with an average reduction in early antibiotic prescribing of 0.43 days [95% confidence interval (CI): 0.22-0.64 days, P < 0.001) and of 0.72 days (95% CI: 0.06-1.38 days, P = 0.03] in total antibiotic prescribing. Baseline PCT testing was not associated with increased mortality or hospital/ICU length of stay or with the rate of antimicrobial-resistant secondary bacterial infections. Baseline PCT testing appears to have been an effective antimicrobial stewardship tool early in the pandemic: it reduced antibiotic prescribing without evidence of harm. Our study highlights the need for embedded, rapid evaluations of infection diagnostics in the National Health Service so that even in challenging circumstances, introduction into clinical practice is supported by evidence for clinical utility. ISRCTN66682918.

Disparities in outcomes by race and ethnicity in the Canadian cystic fibrosis population

BackgroundCystic Fibrosis has historically been described as a disease that affects people of European ancestry. Consequently, much of what we know about CF is based on evidence generated from data collected in white individuals. This may lead to systematic bias in how non-white people with CF are diagnosed and treated. In this study we compared clinical outcomes between the white and non-white people with CF in Canada. MethodsCanadian CF Registry data collected between 2000 and 2019 were used in this population-based cohort study. Demographic characteristics and clinical outcomes of people with CF identified as white and those identified as non-white were compared. Analyses were adjusted for cohort effects but not socioeconomic status. ResultsBetween 2000 and 2019, 5516 people with CF in the Registry were identified as white and 323 were identified as non-white. At diagnosis, the white and non-white groups were similar with respect to sex at birth, age at diagnosis, prevalence of pancreatic insufficiency, and meconium ileus. The non-white group had similar rates of CF-related complications and bacterial infections compared to the white, but worse lung function, worse nutritional status, lower treatment rates, and higher rate of hospitalizations. During the 20-year study period, the non-white group had a 1.85 higher risk of death compared to the white group (HR 95 %CI 1.39; 2.47). InterpretationThere is an urgent need understand why outcomes for Canadians with CF differ between white and non-white individuals, including the role of socioeconomic circumstances.

Long-term outcomes and risk factors for early bacterial infection after pediatric liver transplantation: a prospective cohort study.

Liver transplantation (LT) is the most efficient treatment for pediatric patients with end-stage liver diseases, while bacterial infection is the leading reason for post-transplant mortality. The present study is to explore the outcomes and risk factors of early bacterial infection (within 1 months) after pediatric LT. In this prospective cohort study, 1316 pediatric recipients [median (IQR) age: 9.1 (6.3-28.0) months; male: 48.0%; median (IQR) follow-up time: 40.6 (29.1-51.4) months] who received LT from September 2018 to April 2022 were included. Bacterial culture samples such as sputum, abdominal drainage, blood, and so on were collected when recipients were presented with infective symptoms. Kaplan-Meier analysis was applied to estimate the long-term survival rates and logistic regression was used to identify independent risk factors. To explore the role of pretransplant rectal swab culture (RSC) in reducing post-transplant bacterial infection rate, 188 infant LT recipients [median (IQR) age: 6.8 (5.5-8.1) months; male: 50.5%] from May 2022 to September 2023 were included. Log-binomial regression was used to measure the association of pretransplant RSC screening and post-transplant bacterial infection. The 'Expectation Maximization' algorithm was used to impute the missing data. Bacterial infection was the primary cause for early (38.9%) and overall mortality (35.6%) after pediatric LT. Kaplan-Meier analysis revealed inferior 1-year and 5-year survival rates for recipients with post-transplant bacterial infection (92.6 vs. 97.1%, 91.8 vs. 96.4%, respectively; P <0.001). Among all detected bacteria, Staphylococcus spp. (34.3%) and methicillin-resistant coagulase-negative Staphylococci (43.2%) were the dominant species and multidrug resistant organisms, respectively. Multivariable analysis revealed that infant recipients [adjusted odds ratio (aOR) 1.49; 95% CI: 1.01-2.20], male recipients (aOR, 1.43; 95% CI: 1.08-1.89), high graft-to-recipient weight ratio (aOR, 1.64; 95% CI: 1.17-2.30), positive post-transplant RSC (aOR, 1.45; 95% CI: 1.04-2.02) and nasopharyngeal swab culture (aOR 2.46; 95% CI: 1.72-3.52) were independent risk factors for early bacterial infection. Furthermore, RSC screening and antibiotic prophylaxis before transplantation could result in a relatively lower post-transplant infection rate, albeit without statistical significance (adjusted RR, 0.53; 95% CI: 0.25-1.16). In this cohort study, post-transplant bacterial infection resulted in an inferior long-term patient survival rate. The five identified independent risk factors for post-transplant bacterial infection could guide the prophylaxis strategy of post-transplant bacterial infection in the future. Additionally, pretransplant RSC might decrease post-transplant bacterial infection rate.

Beta-Blockers Lower First Decompensation in Patients With Cirrhosis and Enduring Portal Hypertension After Etiological Treatment

Non-selective beta-blockers (NSBB) can lower the risk of first decompensation in patients with cirrhosis and clinically significant portal hypertension (CSPH) (identified by a hepatic venous pressure gradient ≥10 mmHg) with active etiology. Our aim was to examine the effect of NSBB on first decompensation occurrence in patients with cirrhosis and enduring CSPH after etiological treatment. Patients with compensated cirrhosis and clinical evidence of CSPH (gastroesophageal varices -GEV- and/or spontaneous portosystemic collaterals- SPSS) after two years from etiological treatment. Primary endpoint was first decompensation (occurrence of variceal bleeding, ascites, or hepatic encephalopathy) in patients on-NSBB vs. off-NSBB. Final cohort included 406 patients. Baseline characteristics of patients on-NSBB (n=187) and off-NSBB (n=219) were comparable, except for signs of PH that were more pronounced in the on-NSBB group. During a mean follow-up of 32 months, 127 (31%) patients decompensated, with ascites being the most common (77%) decompensating event. Decompensation rates were lower in patients on-NSBB (16% vs 44%, p<0,0001). The benefit of NSBB on decompensation was maintained in patients with small GEV (17% vs 43%, p<0,0001), in those with SPSS only (8% vs 43%, p=0,003) and in each different etiology, including HCV-cured cirrhosis (9% vs 32%, p<0,0001). At Cox regression analysis, Hemoglobin, Child-Pugh, MELD-Na, diabetes at baseline and previous bacterial infections were independent predictors of decompensation, while NSBB-use had a protective effect (HR 0,32, 95% CI 0,20-0,49; p<0,0001). NSBB-use significantly reduced bacterial infection rates (HR 0,36, 95% CI 0,22-0,58; p<0,0001). NSBB decrease the risk of first decompensation in patients with cirrhosis and enduring CSPH after etiological treatment.

High infection rates and risk‐adapted prevention strategies in contemporary pediatric allogeneic hematopoietic stem cell transplantation

AbstractWith recent changes in hematopoietic stem cell transplantation (HSCT) practices, such as the increasing use of alternative donors and ex vivo T‐cell depletion, how various risk factors interplay and affect the timeline of infections have not been well elucidated. We retrospectively reviewed the first 100 consecutive HSCT from April 2019 to October 2021 in the only pediatric HSCT center in Hong Kong. We found that the vast majority of the allogeneic transplant recipients (69/74, 93.2%) had infections after HSCT, amongst which bacterial, viral, and fungal infection rates were 35.1%, 90.5%, and 9.5%, respectively. In contrast, only 30.8% (8/26) of autologous transplant recipients had infections (rate of bacterial, viral, and fungal infection were 19.2%, 15.4%, and 3.8%, respectively). Human herpesvirus 6 (HHV‐6) and BK virus (BKV) typically occurred early after HSCT, adenovirus (ADV) and varicella zoster virus (VZV) thereafter, and cytomegalovirus (CMV) and Epstein–Barr virus (EBV) throughout the entire 2.5‐year observation period. Ex vivo T‐cell depletion was a general risk factor for viral infection with HHV‐6 (hazard ratio [HR] = 3.03), BKV (HR = 3.36), CMV (HR = 4.45), and EBV (HR = 7.15); all p &lt; 0.02. Cancer in second‐complete remission compared with first‐complete remission was a risk factor for bacterial infection (OR = 6.0, 95% CI = 1.12–32.2, and p = 0.037). Patients with gut graft‐versus‐host disease were at risk for fungal infections (OR = 12.3, 95% CI = 1.33–114.4, and p = 0.027). The infection‐related mortality rate was 10.0%, which occurred only in allogeneic HSCT patients with hematological malignancies receiving cord blood (n = 4) or haploidentical HSCT (n = 6). Collectively, our findings in pediatric patients after contemporary HSCT support both time‐dependent and risk‐adapted measures against infective complications to improve transplant outcome.

Immunosuppressive Induction Therapy Using the Antithymocyteglobulin Grafalon: A Single-Center Non-Interventional Study.

Background: Induction therapy with depleting antibodies in the setting of liver transplantation (LT) is discussed controversially to this day. The rabbit antithymocyteglobulin (ATG) Thymoglobulin (rATG) was introduced as early as 1984 and was frequently used as a standard regime for induction therapy after LT. There are no public reports characterizing Grafalon (ATG-F), a novel ATG, as an induction agent after LT. Objectives: The aim of this observational non-interventional study was to investigate the safety and efficacy of Grafalon induction therapy and characterize its clinical effects in the setting of LT. Methods: A cohort of 80 patients undergoing deceased donor LT at the Medical University of Vienna and receiving Grafalon as part of the clinical standard immunosuppressive regimen was prospectively included between March 2021 and November 2022. Patients were monitored closely for leukocytopenia and thrombocytopenia during the first postoperative week and followed up for incidence and severity of biopsy-proven acute rejection (BPAR), overall survival, and bacterial infections in the first year after LT. Results: The incidences of thrombocytopenia and leukocytopenia following Grafalon treatment peaked on postoperative day four, with 64% and 31%, respectively. However, there were no cases of severe leukocytopenia after the first postoperative week. Induction therapy with Grafalon resulted in a rate of localized bacterial infections and bacteremia of 28% and 21%, respectively. The rate of BPAR was 12.5% in the first year after LT; the one-year survival rate in this cohort was 90%. Conclusions: Overall, this study provides evidence of the safety and efficacy of Grafalon as an induction agent. Further studies investigating the potential long-term effects of Grafalon, as well as comparison studies with different immunosuppressive regimens, are needed in order to draw further conclusions.

Development of a “big data” groundwater microbial contamination index and spatial comparisons with enteric infection rates in southern Ontario

Big data have become increasingly important for policymakers and scientists but have yet to be employed for the development of spatially specific groundwater contamination indices or protecting human and environmental health. The current study sought to develop a series of indices via analyses of three variables: Non-E. coli coliform (NEC) concentration, E. coli concentration, and the calculated NEC:E. coli concentration ratio. A large microbial water quality dataset comprising 1,104,094 samples collected from 292,638 Ontarian wells between 2010 and 2021 was used. Getis-Ord Gi* (Gi*), Local Moran's I (LMI), and space-time scanning were employed for index development based on identified cluster recurrence. Gi* and LMI identify hot and cold spots, i.e., spatially proximal subregions with similarly high or low contamination magnitudes. Indices were statistically compared with mapped well density and age-adjusted enteric infection rates (i.e., campylobacteriosis, cryptosporidiosis, giardiasis, verotoxigenic E. coli (VTEC) enteritis) at a subregional (N = 298) resolution for evaluation and final index selection. Findings suggest that index development via Gi* represented the most efficacious approach. Developed Gi* indices exhibited no correlation with well density, implying that indices are not biased by rural population density. Gi* indices exhibited positive correlations with mapped infection rates, and were particularly associated with higher bacterial (Campylobacter, VTEC) infection rates among younger sub-populations (p < 0.05). Conversely, no association was found between developed indices and giardiasis rates, an infection not typically associated with private groundwater contamination. Findings suggest that a notable proportion of bacterial infections are associated with groundwater and that the developed Gi* index represents an appropriate spatiotemporal reflection of long-term groundwater quality. Bacterial infection correlations with the NEC:E. coli ratio index (p < 0.001) were markedly different compared to correlations with the E. coli index, implying that the ratio may supplement E. coli monitoring as a groundwater assessment metric capable of elucidating contamination mechanisms. This study may serve as a methodological blueprint for the development of big data-based groundwater contamination indices across the globe.

Predictive Modeling of UV-C Inactivation of Microorganisms in Glass, Titanium, and Polyether Ether Ketone

Biomaterials consist of both natural and synthetic components, such as polymers, tissues, living cells, metals, and ceramics. Their purpose is focused on repairing or replacing malfunctioning living tissues and organs. Therefore, it is imperative to ensure the safety and sterility of biomaterials before any contact with living tissue. Ultraviolet (UV)-C irradiation for biomaterial disinfection has been considered due to the high recurrence rate of bacterial infections and to prevent resistance. Physical composition and surface properties and UV-C sensitivity of microorganisms can alter its efficacy. The main objective of this study was to evaluate the efficacy of UV-C in terms of microbial lethality and additional underlying factors contributing to its performance, namely the surface properties. For this purpose, twelve different strains were first screened, from which four microorganism species known to have the ability to cause nosocomial infections were further tested, namely Escherichia coli, Pseudomonas aeruginosa, Candida albicans, and Candida glabrata. These microorganisms were inoculated onto slides and disks of various bio contact surfaces, including glass (GLS), titanium (Ti), and poly ether etherketone (PEEK), and exposed to UV-C. The results demonstrate that bacterial pathogens on biomaterial surfaces respond differently to UV-C light exposure, and the bactericidal effect decreased in this order: glass, PEEK, and Ti (0.5 to 2.0 log reduction differences). P. aeruginosa ATCC 27853 on glass surfaces was reduced to an undetectable level after being exposed to 6.31 J.cm−2 of UV-C, displaying the highest reduction rate observed among all the tested microorganisms, 2.90 J−1.cm−3, compared to Ti and PEEK. Similarly, a higher reduction in C. glabrata ATCC 2001 was observed on glass; the modeled inhibition displayed a rate of 1.30 J−1.cm−3, the highest observed rate among yeast, compared to Ti and PEEK, displaying rates of 0.10 J−1.cm−3 and 0.04 J−1.cm−3, respectively. The inactivation rates were higher for less hydrophobic materials with smoother surfaces as compared to biomaterials with rougher surfaces.

Association of antibiotics with the outcomes in COVID-19 pneumonia patients with elevated PCT levels

ObjectiveTo assess antibiotics impact on outcomes in COVID-19 pneumonia patients with varying procalcitonin (PCT) levels. MethodsThis retrospective cohort study included 3665 COVID-19 pneumonia patients hospitalized at five Mayo Clinic sites (March 2020 to June 2022). PCT levels were measured at admission. Patients’ antibiotics use and outcomes were collected via the Society of Critical Care Medicine (SCCM) Viral Infection and Respiratory Illness Universal Study (VIRUS) registry. Patients were stratified into high and low PCT groups based on the first available PCT result. The distinction between high and low PCT was demarcated at both 0.25 ng/ml and 0.50 ng/ml. ResultsOur cohort consisted of 3665 patients admitted with COVID-19 pneumonia. The population was predominantly male, Caucasian and non-Hispanic. With the PCT cut-off of 0.25 ng/ml, 2375 (64.8 %) patients had a PCT level <0.25 ng/mL, and 1290 (35.2 %) had PCT ≥0.25 ng/ml. While when the PCT cut off of 0.50 ng/ml was used we observed 2934 (80.05 %) patients with a PCT <0.50 ng/ml while 731(19.94 %) patients had a PCT ≥0.50 ng/ml. Patients with higher PCT levels exhibited significantly higher rates of bacterial infections (0.25 ng/ml cut-off: 4.2 % vs 7.9 %; 0.50 ng/ml cut-off: 4.6 % vs 9.2 %).Antibiotics were used in 66.0 % of the cohort. Regardless of the PCT cutoffs, the antibiotics group showed increased hospital length of stay (LOS), intensive care unit (ICU) admission rate, and mortality. However, early de-escalation (<24 h) of antibiotics correlated with reduced hospital LOS, ICU LOS, and mortality. These results were consistent even after adjusting for confounders. ConclusionOur study shows a substantial number of COVID-19 pneumonia patients received antibiotics despite a low incidence of bacterial infections. Therefore, antibiotics use in COVID pneumonia patients with PCT <0.5 in the absence of clinical evidence of bacterial infection has no beneficial effect.

The John Charnley Award: The Impact of Human Leukocyte Antigen Genotype on Bacterial Infection Rates and Successful Eradication in Total Hip Arthroplasty

BackgroundGenetics play an important role in several medical domains; however, the influence of human leukocyte antigen (HLA) genotype on the development of periprosthetic joint infection (PJI) in total hip arthroplasty (THA) remains unknown. The primary aim of this study was to determine if HLA genotype is associated with the development of bacterial PJI in THA. Secondarily, we evaluated the association between HLA genotype and PJI treatment success. MethodsA retrospective, matched, case-control study was performed using prospectively collected data from a single institution. A total of 49 patients who underwent primary THA were included, with a mean follow-up of 8.5 years (range, 4.2 to 12.9). The 23 cases (PJI) and 26 controls (no PJI) were matched for age, sex, follow-up, body mass index, primary diagnosis, and comorbidities (P > .05). High-resolution genetic analysis targeting 11 separate HLA loci was performed in all patients using serum samples. The HLA gene frequencies and carriage rates were determined and compared between cohorts. A subgroup analysis of PJI treatment success (18) and failure (5) was performed. Statistical significance was set at P = .10 for genetic analysis and at 0.05 for all other analyses. ResultsThere were 4 HLA alleles that were significantly associated with the development of PJI. The 3 at-risk alleles included HLA-C∗06:02 (odds ratio 5.25, 95% CI [confidence interval] 0.96 to 28.6, P = .064), HLA-DQA1∗04:01 (P = .096), and HLA-DQB1∗04:02 (P = .096). The single protective allele was HLA-C∗03:04 (odds ratio 0.12, 95% CI 0.01 to 1.10, P = .052). There were no specific HLA alleles that were associated with treatment success or failure. ConclusionsThis study suggests that there are at-risk and protective HLA alleles associated with the development of PJI in THA. To our knowledge, this is the first study to demonstrate an association between patient HLA genotype and the development of PJI. A larger study of the subject matter is necessary and warranted.

Antibiotic prescribing and bacterial infection in COVID-19 inpatients in Southeast Asia: a systematic review and meta-analysis.

The prescribing of antibiotics to treat COVID-19 patients has been observed to occur frequently, often without clear justification. This trend raises concerns that it may have exacerbated antimicrobial resistance (AMR). Despite longstanding concerns over AMR in Southeast Asian countries, data on this issue are notably lacking. To explore the impact of COVID-19 on antibiotic prescribing, bacterial infection prevalence and common resistant pathogens in COVID-19 inpatients. We searched PubMed, EMBASE, Web of Science and ThaiJO (a Thai academic database) to identify studies conducted in ASEAN member countries and published between December 2019 and March 2023. Screening and data extraction were done by two independent reviewers, with results synthesized using random-effects meta-analyses and descriptive statistical analyses. This review was registered with PROSPERO (CRD42023454337). Of the 29 studies (19 750 confirmed COVID-19 cases) included for final analysis, the antibiotic prescribing rate was 62.0% (95%CI: 46.0%-76.0%) with a prescribing rate of 58.0% (21.0%-91.0%) in mild/moderate cases versus 91.0% (82.0%-98.0%) in severe/critical cases. Notably, 80.5% of antibiotics prescribed fall under the WHO AWaRe 'Watch' list, followed by 'Access' at 18.4% and 'Reserve' at 1.0%. The reported bacterial infection prevalence was 16.0% (7.0%-29.0%), with Acinetobacter baumannii being the most common resistant bacterium at 7.7%. Singapore was notable for its lower antibiotic prescribing rate of 17.0% and a lower bacterial infection rate of 10.0%. High antibiotic prescribing rates, disproportionate to bacterial infections and varying practices for COVID-19 inpatients across countries highlight the urgent need for this region to collaborate to tackle and mitigate AMR.

Seasonal meropenem resistance in Acinetobacter baumannii and influence of temperature-driven adaptation

BackgroundRecognition of seasonal trends in bacterial infection and drug resistance rates may enhance diagnosis, direct therapeutic strategies, and inform preventive measures. Limited data exist on the seasonal variability of Acinetobacter baumannii. We investigated the seasonality of A. baumannii, the correlation between temperature and meropenem resistance, and the impact of temperature on this bacterium.ResultsMeropenem resistance rates increased with lower temperatures, peaking in winter/colder months. Nonresistant strain detection exhibited temperature-dependent seasonality, rising in summer/warmer months and declining in winter/colder months. In contrast, resistant strains showed no seasonality. Variations in meropenem-resistant and nonresistant bacterial resilience to temperature changes were observed. Nonresistant strains displayed growth advantages at temperatures ≥ 25 °C, whereas meropenem-resistant A. baumannii with β-lactamase OXA-23 exhibited greater resistance to low-temperature (4 °C) stress. Furthermore, at 4 °C, A. baumannii upregulated carbapenem resistance-related genes (adeJ, oxa-51, and oxa-23) and increased meropenem stress tolerance.ConclusionsMeropenem resistance rates in A. baumannii display seasonality and are negatively correlated with local temperature, with rates peaking in winter, possibly linked to the differential adaptation of resistant and nonresistant isolates to temperature fluctuations. Furthermore, due to significant resistance rate variations between quarters, compiling monthly or quarterly reports might enhance comprehension of antibiotic resistance trends. Consequently, this could assist in formulating strategies to control and prevent resistance within healthcare facilities.