Bacterial Infections and Mycoses Commons^™

Resensitization Of Clinical Isolates Of Mdr-Acinetobacter Baumannii To Antibiotics Using Bacteriophage Therapy, Priyal Gajera, Valerie J. Carabetta

Rowan-Virtua Research Day

Introduction:

Antibiotic resistance poses a major global health threat, particularly with multidrug-resistant (MDR) pathogens such as Acinetobacter baumannii, which exhibits resistance to multiple antibiotic classes, including carbapenems.¹ As conventional treatments become less effective, alternative therapies such as bacteriophage therapy are gaining attention. Bacteriophages offer targeted antibacterial activity and may enhance antibiotic efficacy or resensitize resistant strains. This study investigates the synergistic effects of bacteriophage ΦCO03 combined with antibiotics against MDR A. baumannii.

Methods:

Clinical isolates (M20, M5) of A. baumannii were cultured in LB broth at 37°C. Bacteriophage ΦCO03 was isolated and purified using plaque assays. Synergy between phage …

Bacteriophage Therapy Vs. Standard Antibiotics: A Review Of Treatment Efficacy For Recurrent Pediatric S. Pyogenes (Gas) Infections, Kartik Kannan Oms-I, Karina Malhotra Oms-I, Gabrielle Coccio Oms-I, Janhavi Belwalkar Oms-I, Jason Rienzo Oms-I, Samay Shukla Oms-I, Valerie J. Carabetta Phd

Rowan-Virtua Research Day

Background: Antibiotic resistance poses a growing threat to pediatric infectious disease management, particularly in the treatment of Streptococcus pyogenes (GAS) infections.¹ While β-lactam antibiotics remain the first-line standard of care, their utility is limited by allergy prevalence and rising resistance among alternative antibiotic agents, such as macrolides, lincosamides, and tetracycline.^2,3 Given these trends, bacteriophage therapy has emerged as a promising adjunctive treatment modality, offering targeted bacterial lysis while sparing commensal microbiota.⁴

Methods: A systematic literature search was conducted across PubMed and Embase (2000–2025) using terms related to antibiotic resistance, Streptococcus pyogenes, bacteriophage therapy, and pediatric populations. …

Investigating The Synthesis And Antibacterial Activity Of A Main-Chain Cationic Polymer, Emily Smith

Honors Theses

Antibiotic resistance is a growing threat to public health. Due to the overuse of antibiotics in agriculture, the overprescription of antibiotics, and the misuse of antibiotics by patients, antibiotic resistance is spreading at an alarming rate. As antibiotic resistance spreads, the antibiotics we depend on to treat common infections become ineffective. Therefore, it is imperative to develop novel treatments for infections that do not increase the prevalence of antibiotic resistance. One treatment being explored is the use of synthetic polymers with antibacterial properties. Synthetic polymers are advantageous because they can be synthesized from widely available precursors and their structure is …

Synergistic Cefiderocol-Containing Antibiotic Combinations Active Against Highly Drug-Resistant Acinetobacter Baumannii Patient Isolates With Diverse Resistance Mechanisms, Justin Halim, Andrew P. Keane, Jeannete Bouzo, Tope Aderibigbe, Jessica A. Chicola, Katie T. Nolan, Keertana Jonnalagadda, Jason X. Tran, Valerie J. Carabetta

Rowan-Virtua School of Osteopathic Medicine Departmental Research

BACKGROUND: Acinetobacter baumannii is a nosocomial pathogen known for rapidly developing resistance to nearly all antibiotics, including last-line agents. Cefiderocol, a novel siderophore cephalosporin, has shown in vitro activity against A. baumannii and is now used clinically, but resistance is emerging. Data on cefiderocol-based antibiotic combinations are limited.

OBJECTIVES: To evaluate the in vitro activity of cefiderocol alone and in combination with other antibiotics against XDR and PDR A. baumannii clinical isolates, and to explore resistance mechanisms underlying cefiderocol synergy.

METHODS: We tested 21 XDR/PDR clinical isolates and one NDM-1-producing strain using broth microdilution and checkerboard assays with cefiderocol and …

Addressing Socioeconomic Disparities In The Treatment Of Antimicrobial-Resistant Infections: The Role Of Pharmacists In Mitigating Barriers, Arin Wade, Danielle Egbujor, Anna Spalvieri, Owen Fox, Marisa Petrunich, Joshua Honaker, Samantha Mccord, Kasie Landin

Pharmacy and Wellness Review

Antimicrobial resistance is an escalating global threat driven by inappropriate antibiotic use and shaped by socioeconomic disparities. Social determinants of health, including limited healthcare access, poverty, low health literacy, and environmental conditions, contribute to higher rates of resistant infections and poorer treatment outcomes in underserved populations. Barriers such as pharmacy deserts, self-medication, and inadequate stewardship infrastructure amplify these risks. Pharmacists, as accessible and highly trained healthcare professionals, play a critical role in combating antimicrobial resistance by optimizing antibiotic use, delivering culturally competent education, and leading antimicrobial stewardship programs across settings. Community and clinical pharmacists are especially well positioned to bridge …

Assessing The Efficacy Of Prolonged Doxycycline Pep Use In High-Risk Populations For Sti Prevention, Lam Doan, Pearl Joslyn, Lizann Sung, Timothy Breiner, Sarah Marotta, Shikhar Rastogi

Rowan-Virtua Research Day

First recommended in October 2022, doxycycline post-exposure prophylaxis (DoxyPEP) has been increasingly used as a treatment for multiple sexually transmitted infections (STIs). To evaluate the efficacy of prolonged DoxyPEP use in high risk populations - men who have sex with men (MSM) and transgender women - for STIs, different sources addressing various aspects of DoxyPEP, its efficacy in STI prevention, and the potential consequences of its widespread use in terms of antimicrobial resistance were examined. Across 9 studies, DoxyPEP was found to decrease the incidence of bacterial STIs, specifically, syphilis, chlamydia, and gonorrhea with varying efficacy, especially for gonorrhea. Furthermore, …

Clinical Characteristics And Outcomes Of Pediatric Staphylococcal Scalded Skin Syndrome (Ssss) At An Inner-City Tertiary Care Center, Nina Kb Gust Md, Ashley Frei Bs, Rebecca M. Adams Bs, Elika Ridelman Phd, Christina Shanti Md, Ronald Thomas Phd, Jocelyn Y. Ang Md

Medical Student Research Symposium

Introduction

Staphylococcal Scalded Skin Syndrome (SSSS) is a blistering skin condition caused by a toxin-producing staphylococcus species. Epidemiologic studies on pediatric SSSS in the United States are limited, with a reported incidence of 7.67 cases per million children and 45.1 per million infants. Immature renal function, lack of protective antibodies, and increased exotoxin target desmoglein-1 are hypothesized to increase incidence in younger children. We aimed to determine clinical and microbiological characteristics of pediatric SSSS and factors that could help predict disease severity.

Methods

A retrospective chart review was performed for admitted patients under 18 years old diagnosed with SSSS from …

The Role Of Horizontal Gene Transfer In Antibiotic Resistance Amidst Prevalent Community And Healthcare-Associated Mrsa Rates, Gabrielle Nascimento

Honors College Theses

In recent decades, cases of community-acquired MRSA (CA-MRSA) and healthcare-associated MRSA (HA-MRSA) have been on the rise. The ability of antibiotic resistance to transfer between microorganisms greatly expands its threat to the effective treatment and containment of bacterial infections. The mecA gene is found on a mobile cassette within the Staphylococcal cell and encodes for PBP2a, an alternate version of penicillin-binding protein (PBP) with less binding affinity for β-lactam antibiotics, increasing resistance to the effects of antibiotics. The goal of this research is to investigate the horizontal transfer of the mecA gene between various Staphylococcus species as well as to …

Ribosome Hibernation In Mycobacterium Abscessus And Its Effect On Antibiotic Resistance, Ryan Treen

Electronic Theses & Dissertations (2024 - present)

Non-tuberculosis mycobacteria (NTM) represent a diverse repertoire of species, most of which are ubiquitous in the environment. Some NTM species, such as Mycobacterium abscessus, can cause life-threatening infections in people with underlying medical conditions. The clinical incidence of such infections is on the rise, posing an emerging threat to public health. M. abscessus is characterized by intrinsic and acquired antibiotic resistance, complicating treatment strategies. Most chemotherapeutic approaches for M. abscessus infection target the bacterial ribosome, necessitating a better understanding of the physiological processes which confer this resistance. Multiple mycobacterial species respond to zinc-limiting conditions by inducing remodeling and hibernation …

Design, Synthesis, And Nmr-Guided Characterization Of A Targeted Covalent Inhibitor-Like Molecule Against Ivyp1 From P. Aeruginosa, Samuel Taylor Moore

Master's Theses

Multi-drug resistance poses a serious threat to future generations and historical antibiotic pipelines; consequently, the medical and economic burdens associated with treating multidrug-resistant bacteria are substantiated. In this context, P. aeruginosa (PA) emerges as one of the most significant healthcare challenges, being a leading cause of resistance-associated mortality worldwide. Despite modern efforts to combat these poor outcomes, drug-resistant cases continue to rise, and the need for novel antibiotic treatment is apparent. To this end, we investigated relevant resistance mechanisms and past antibiotic targets within PA, and in doing so, we identified relationships between peptidoglycan biology and a periplasmic protein, Inhibitor …

Exploration Of Enterococcus Faecalis Bacteriophages Diversity: Comprehensive Phylogenetic Analysis And Discovery Isolation Of Enterococcus Faecalis Phage From A Soil Sample In South Florida, Hailey N. Jauernick

All HCAS Student Capstones, Theses, and Dissertations

Enterococcus faecalis is a commensal bacterium found in the gastrointestinal tract, oral cavity, and vagina of humans, which can transition to pathogenic states, leading to diverse infections. Many E. faecalis infections are becoming progressively challenging to treat, stemming from the lack of effective antibiotic therapies against its virulence factors, including biofilm formation and antibiotic resistance. Phage therapy emerges as a promising alternative, targeting bacteria with minimal impact on host flora. However, despite phages' ubiquitous presence and potential applications in medicine and biotechnology, their diversity and ecological niches are vastly understudied. Here, we investigated the diversity of sequenced E. faecalis phages …

Diagnosis And Treatment Of Helicobacter Pylori, Erin Raspet

Pacific Journal of Health

Helicobacter pylori is a widespread infectious disease most commonly associated with gastritis, peptic ulcer disease, and gastric cancer. The ability of this organism to influence immune function has been associated with a proinflammatory state that has been associated with several other conditions that can lead to significant mortality and morbidity. Treatment is possible with antibiotic regimens, however, increasing resistance requires treatment be informed by susceptibility information followed by a test of cure to ensure eradication of the infection. Given the global burden of this infection, it is important for providers to appropriately identify, diagnosis, and treat this condition to reduce …

The Implications Of Ferroptosis In Antibiotic Resistance, Marysol Hohl

Senior Honors Theses

Bacterial infections in the United States are becoming increasingly resistant to existing antibiotic treatments. Due to projected increases in resistance and the recent decrease in novel antibacterials, experts have determined that the United States is in the “post-antibiotic era.” The scientific community has failed to resolve resistance despite the continual discovery of new antibiotic compounds. In the past decade, a novel form of cell death called ferroptosis has been implicated in antibiotic treatment by employing the use of nanotechnology. This literature review will describe the problem of bacterial resistance and demonstrate how current research is pioneering a new age of …

A Review Of Staphylococcus Aureus Pathogenesis, Global Impact, And The Rise Of Antibiotic-Resistant Clones, Anders Kleinbeck

Honors Scholar Theses

Staphylococcus aureus is a pathogen of grave concern to global public health. The pathogen has shown an unrivaled propensity to obtain resistance to nearly every antibiotic drug approved and prescribed for its treatment. This review will provide an overview of the history and evolution of S. aureus, including an analysis of its transition from the nosocomial setting to the community and the factors contributing to the species’ innate pathogenicity. This paper will also discuss the molecular mechanisms by which resistance to a wide range of popular antibiotic substances was obtained and will provide insight into the evolutionary patterns exhibited by …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Multiplex Pcr Assay To Detect High Risk Lineages Of Salmonella Typhi And Paratyphi A, Fahad Khokhar, Derek Pickard, Zoe Dyson, Junaid Iqbal, Agila Pragasam, Jobin Jacob John, Balaji Veeraraghavan, Farah Qamar, Gordon Dougan, Hilary Macqueen

Department of Paediatrics and Child Health

Enteric fever infections remain a significant public health issue, with up to 20 million infections per year. Increasing rates of antibiotic resistant strains have rendered many first-line antibiotics potentially ineffective. Genotype 4.3.1 (H58) is the main circulating lineage of S. Typhi in many South Asian countries and is associated with high levels of antibiotic resistance. The emergence and spread of extensively drug resistant (XDR) typhoid strains has increased the need for a rapid molecular test to identify and track these high-risk lineages for surveillance and vaccine prioritisation. Current methods require samples to be cultured for several days, followed by DNA …

Effect Of Sub-Inhibitory Concentrations Of Nitrofurantoin, Ciprofloxacin And Trimethoprim On In-Vitro Biofilm Formation In Uropathogenic Escherichia Coli, Shane Whelan

ORBioM (Open Research BioSciences Meeting)

The purpose of the current study was to determine the effect of sublethal concentrations of nitrofurantoin, ciprofloxacin and trimethoprim on biofilm formation in 57 uropathogenic Escherichia coli strains (UPEC).

The MIC of nitrofurantoin, ciprofloxacin and trimethoprim was determined for 57 UPEC isolates. Biofilm formation for each isolate with and without sub-lethal concentrations of each antibiotic was then quantified, and the statistical significance of changes in biofilm formation was ascertained by way of a Dunnett's test.

The effects of sub-MIC antibiotics on biofilm formation of UPEC were variable. A total of 22.8% of strains were induced to form biofilm by nitrofurantoin, …

Resolving The Repression Pathway Of Virulence Gene Hila In Salmonella, Alexandra King, Lon Chubiz Phd, Brenda Pratte, Lauren Daugherty

Undergraduate Research Symposium

Salmonella is a relatively abundant, virulent species of bacteria that is most known for spreading gastrointestinal diseases through food. These illnesses result in approximately 1.35 million infections, including over 25,000 hospitalizations each year, in the U.S. alone (CDC.gov). As antibiotic resistance becomes an increasingly urgent public health problem, the importance of developing alternative treatment methods is only becoming more crucial. One of the genes responsible for this virulence is known as hilA. HilA is the main transcriptional regulator of Salmonella Pathogenicity Island-1 gene (UniProt). SPI-1 plays an important role in the invasion of Salmonella into epithelial cells. The proteins encoded …

Assesment Of Antibiotic Resistant Gene Expression In Clinical Isolates Of Pseudomonas Aeruginosa, Dustin Esmond

Biology Theses

Increasing prevalence of nosocomial infections by antimicrobial resistant pathogens resulting in higher mortality rates and financial burden is of great concern. Pseudomonas aeruginosa represents one of six highly virulent “ESKAPE” pathogens that exhibit considerable intrinsic drug resistance as well as mechanisms for acquiring further resistance. As many of these mechanisms are regulated through gene expression, we sought to identify regulatory strategies and patterns at play in 23 clinical isolates collected from Baku, Azerbaijan and Tyler, Texas, USA. Real-time quantitative polymerase chain reaction was performed on six gene targets implicated in resistance and contrasted with antibiotic phenotypes. We found AmpC cephalosporinase …

Antibiotic Tolerance And Heteroresistance: Associated Fitness Costs And Potential In Evading Antibiotic Killing, Tina H. Dao

Theses and Dissertations (ETD)

Streptococcus pneumoniae is a prominent human pathogen that causes both invasive and non-invasive diseases, such as otitis media, pneumonia, meningitis, and bacteremia. Although it is frequently an asymptomatic colonizer of the human nasopharynx, S. pneumoniae is a major cause of morbidity and mortality in the immune compromised population, young children, and the elderly. Up until the 1970s, S. pneumoniae was susceptible to almost all antibiotics. Since then, this pathogen has gained resistance to a variety of antibiotic treatments, including beta-lactams, macrolides, and fluoroquinolones.

In the first chapter, we focused on fluoroquinolone resistance in S. pneumoniae. Fluoroquinolones are one of the …

Contributions Of Gyra And Parc Mutations And Qnrs2 Acquisition To Ciprofloxacin Resistance In Aeromonas Veronii Hm21, Daniel J. Silverstein

Honors Scholar Theses

In recent years, ciprofloxacin resistant (CpR) Aeromonas veronii and A. hydrophila strains have been isolated from the wounds of patients receiving leech therapy. Genome comparisons of these CpR isolates revealed the presence of chromosomal mutations in gyrA and parC as well as the gain of qnrS2 on either a large, 34 kb, conjugatable, low-copy plasmid, pAv42, or on a small, 6.8 kb, high-copy plasmid, pAh1471. The minimum inhibitory concentration, MIC, for Cp of these clinical isolates ranged from 1 to ≥32 µg/mL and some harbored a qnrS2 containing plasmid. We wanted to assess the contributions of these factors in an …

The Effects Of Farnesol, A Quorum Sensing Molecule From Candida Albicans, On Alcaligenes Faecalis, Savannah Hutson

Undergraduate Honors Theses

Quorum sensing molecules have become a recent focus of study to learn if and how they can be used, both on their own and in conjecture with current antimicrobial methods, as a means of bacterial control. One such quorum sensing molecule is the sesquiterpene alcohol, Farnesol, which is synthesized and released by the fungus, Candida albicans. In most in-vivo cases, our laboratory has shown that Alcaligenes faecalis overtakes C. albicans, preventing its growth. However, as a way to counteract this inhibitory effect, Farnesol may be one way that Candida has found to fight back. In this study, we …

Mrsa In The United States, Sweden, And Syria, Derek J. Lillestolen

Montview Journal of Research & Scholarship

Methicillin-resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen that is resistant to many broad and narrow-spectrum antibiotics commonly used in the treatment of S. aureus. There has been much fanfare about MRSA, receiving nicknames like “superbug” because of its varying degrees of resistance to the most common broad and narrow-spectrum antibiotics such as penicillin, oxacillin, methicillin and amoxicillin (2). The reality, however, is that MRSA is still susceptible to certain antibiotics and can be treated effectively. This study displays the factors which help and hurt MRSA treatments. There is shown a strong link between the prescription of broad-spectrum antibiotics …

The Inhibitory Effects Of A Novel Gel On Staphylococcus Aureus Biofilms, Lindsey Vance

Undergraduate Honors Theses

Antibiotic resistance is an ever-growing topic of concern within the medical field causing researchers to examine the mechanisms of resistance to develop new antimicrobials. Bacteria’s ability to form biofilms is one mechanism which aids in antimicrobial resistance. Staphylococcus aureus is of special interest as it is one of the most frequent biofilm-forming bacteria found on medical devices causing infections and posing dangerous threats in a clinical setting. A recently developed antimicrobial gel has been shown to have profound effects on treating bacterial infections and wound healing. This research is centered upon examining the antimicrobial effects of this gel on the …

Antibiotic Prophylaxis Is Associated With Subsequent Resistant Infections In Children With An Initial Extended-Spectrum-Cephalosporin-Resistant Enterobacteriaceae Infection., Sibani Das, Amanda L. Adler, Arianna Miles-Jay, Matthew P. Kronman, Xuan Qin, Scott J. Weissman, C A. Burnham, Alexis Elward, Jason G. Newland, Rangaraj Selvarangan, Kaede V. Sullivan, Theoklis Zaoutis, Danielle M. Zerr

Manuscripts, Articles, Book Chapters and Other Papers

The objective of this study was to assess the association between previous antibiotic use, particularly long-term prophylaxis, and the occurrence of subsequent resistant infections in children with index infections due to extended-spectrum-cephalosporin-resistant Enterobacteriaceae We also investigated the concordance of the index and subsequent isolates. Extended-spectrum-cephalosporin-resistant Escherichia coli and Klebsiella spp. isolated from normally sterile sites of patients aged species, resistance determinants, and fumC-fimH (E. coli) or tonB (Klebsiella pneumoniae) type were identical to those of the index isolate. In total, 323 patients had 396 resistant isolates; 45 (14%) patients had ≥1 subsequent resistant infection, totaling 73 …

The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman

Honors Projects

Lake Erie has experienced harmful algal blooms with increased frequency since the mid-1990s due to excess nutrients from Rivers, such as the Maumee River, and largely agricultural watersheds. Nonpoint source pollution from agriculture contributes to eutrophication, algal blooms, and the degradation of water quality. This creates stress on aquatic fauna, reduced aesthetic quality, odor, and limits of the water for usage of drinking, recreation, and industry. This research paper asks what the contributions of having access to manure application records, soil records, and information about antibiotics have on what is known about manure management and antibiotic resistance, which has been …