Bacterial Infections and Mycoses Commons^™

Nanosecond Pulsed Electric Fields Increase Antibiotic Susceptibility In Methicillin-Resistant Staphylococcus Aureus, Alexandra E. Chittams-Miles, Areej Malik, Erin B. Purcell, Claudia Muratori

Bioelectrics Publications

Staphylococcus aureus is the leading cause of skin and soft-tissue infections (SSTIs). SSTIs caused by bacteria resistant to antimicrobials, such as methicillin-resistant S. aureus (MRSA), are increasing in incidence and have led to higher rates of hospitalization. In this study, we measured MRSA inactivation by nanosecond pulsed electric fields (nsPEF), a promising new cell ablation technology. Our results show that treatment with 120 pulses of 600 ns duration (28 kV/cm, 1 Hz), caused modest inactivation, indicating cellular damage. We anticipated that the perturbation created by nsPEF could increase antibiotic efficacy if nsPEF were applied as a co-treatment. To test this …

Additive Effects Of Cyclic Peptide [R4w4] When Added Alongside Azithromycin And Rifampicin Against Mycobacterium Avium Infection, Melissa Kelley, Kayvan Sasaninia, Arbi Abnousian, Ali Badaoui, James Owens, Abrianna Beever, Nala Kachour, Rakesh Kumar Tiwari, Vishwanath Venketaraman

Pharmacy Faculty Articles and Research

Mycobacterium avium (M. avium), a type of nontuberculous mycobacteria (NTM), poses a risk for pulmonary infections and disseminated infections in immunocompromised individuals. Conventional treatment consists of a 12-month regimen of the first-line antibiotics rifampicin and azithromycin. However, the treatment duration and low antibiotic tolerability present challenges in the treatment of M. avium infection. Furthermore, the emergence of multidrug-resistant mycobacterium strains prompts a need for novel treatments against M. avium infection. This study aims to test the efficacy of a novel antimicrobial peptide, cyclic [R4W4], alongside the first-line antibiotics azithromycin and rifampicin in reducing M. avium survival. Colony-forming unit (CFU) …

Outpatient Sexually Transmitted Infection Testing And Treatment Patterns In The United States: A Real-World Database Study, Rebecca Lillis, Louis Kuritzky, Zune Huynh, Rodney Arcenas, Avneet Hansra, Roma Shah, Baiyu Yang, Stephanie N. Taylor

School of Medicine Faculty Publications

Background: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the most common notifiable sexually transmitted infections (STIs) in the United States. Because symptoms of these infections often overlap with other urogenital infections, misdiagnosis and incorrect treatment can occur unless appropriate STI diagnostic testing is performed in clinical settings. The objective of this study was to describe STI diagnostic testing and antimicrobial treatment patterns and trends among adolescent and adult men and women with lower genitourinary tract symptoms (LGUTS). Methods: We analyzed insurance claims data from the IBM® MarketScan® Research Databases. Patients included were between 14 and 64 years old with …

Elucidating The Impact Of Sos-Response Timing In On Escherichia Coli Survival Following Treatment With Fluoroquinolone Topoisomerase Inhibitors, Stephanie Schofield

Honors Scholar Theses

Antibiotic treatment failure is a public health crisis, with a 2019 report stating that roughly 35,000 deaths occur in the United States yearly due to bacterial infections that are unresponsive to antibiotics (1). One complication in the treatment of bacterial infection is antibiotic persistence which further compromises our battle to effectively treat infection. Bacterial persisters can exist in clonal bacterial cultures and can tolerate antibiotic treatment by undergoing reversible phenotypic changes. They can survive drug concentrations that their genetically identical kin cannot. Some persisters remain in a slow growing state and are difficult to target with current antibiotics. A specific …

Topical Anesthetic Gel Interferes With Antibacterial Efficacy Of Povidone-Iodine Both In Vitro And In Vivo, Cecilly Kelleher Bs, Jacob Im Md, Linda Kang Bs, Aleksey Mishulin Md, Sukhvinder Singh Phd, Ashok Kumar Phd

Medical Student Research Symposium

Purpose: To evaluate the effects of viscous lidocaine gel on the antimicrobial efficacy of povidone-iodine (PI) and their order of application in both in vitro and in vivo models.

Methods: In vitro antibacterial effects were tested against Staphylococcus aureus (S. aureus) with disc diffusion methods for application of lidocaine alone, PI alone, PI before lidocaine, and lidocaine before PI. Zones of inhibition were measured after incubation at 37°C overnight. Mouse eyes were colonized with S. aureus for in vivo study to which PI and/or lidocaine were applied in various combinations. Eyes were then rinsed with saline, and …

Emergence Of A Multidrug-Resistant And Virulent Streptococcus Pneumoniae Lineage Mediates Serotype Replacement After Pcv13: An International Whole-Genome Sequencing Study, Stephanie W. Lo, Kate Mellor, Robert Cohen, Alba Redin Alonso, Sophie Belman, Narender Kumar, Paulina A. Hawkins, Rebecca A. Gladstone, Sadia Shakoor, Muhammad Imran Nisar

Department of Pathology and Laboratory Medicine

Background: Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context.
Methods: Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster …

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 …

Predominantly Methicillin-Susceptible S. Aureus Bacteria Found In Csp Students’ S. Aureus Strains, Roma Ambo

Research and Scholarship Symposium Posters

Positive Staphylococcus aureus strains from CSP students were tested for methicillin resistance (MRSA) using the Kirby-bauer assay. Kirby-bauer assay technique was used to determine the sensitivity of staphylococcus aureus bacteria against oxacillin. MRSA infection is the result of a bacteria that has built resistance against the antibiotics used to treat staph infections. The results of this experiment concludes that majority of the strains tested are methicillin-susceptible S. aureus (MSSA).

Etiology, Clinical Characteristics, And Outcome Of Infective Endocarditis: 10-Year Experience From A Tertiary Care Center In Pakistan, Sara Salim Ali, Imran Ahmed Qureshi, Ahmed Ayaz, Ainan Arshad, Awais Farhad, Bushra Jamil, Muhammad Rizwan Sohail

Medical College Documents

This study was conducted to assess the clinical characteristics, causative agents, complications, and outcomes of infective endocarditis (IE) among patients presenting to our tertiary care center over the last decade. This retrospective cohort study included all adult patients admitted to the Aga Khan University Hospital with the diagnosis of IE over a ten-year period from 2010 to 2020. Outcomes variables included complications during hospitalization, surgical intervention, mortality, and length of stay. We identified a total of 305 cases out of which 176 (58%) were males and 129 (42%) were females. The mean age of the patients was 46.9±18.8 years. 95 …

Catheter-Associated Urinary Tract Infections: Patient Characteristics, Treatment, And Clinical Outcomes In One South Texas Acute Care Hospital, Kimberly A. Ambrosini, Jose Campo Maldonado

MEDI 9331 Scholarly Activities Clinical Years

Background: Catheter-associated urinary tract infections (CA-UTIs) account for 40 percent of nosocomial infections worldwide. Their elimination is at the forefront of quality improvement in one South Texas acute care hospital.

Methods: Over a period of 6 months, five CA-UTIs occurred in one South Texas acute care hospital. These cases were identified via regular surveillance by Infection Prevention staff and the Laboratory Department of the hospital. This research reviews patient age, sex, length of stay, bacteria contracted, appropriate antibiotic use, patient characteristics, and overall outcomes.

Results: Between the months of July and December 2021, 5 CAUTIs were contracted. Patients …

When The Pandemic Opts For The Lockdown: Secretion System Evolution In The Cholera Bacterium, Francis J. Santoriello, Stefan Pukatzki

Publications and Research

Vibrio cholerae, the causative agent of the diarrheal disease cholera, is a microbe capable of inhabiting two different ecosystems: chitinous surfaces in brackish, estuarine waters and the epithelial lining of the human gastrointestinal tract. V. cholerae defends against competitive microorganisms with a contact-dependent, contractile killing machine called the type VI secretion system (T6SS) in each of these niches. The T6SS resembles an inverted T4 bacteriophage tail and is used to deliver toxic effector proteins into neighboring cells. Pandemic strains of V. cholerae encode a unique set of T6SS effector proteins, which may play a role in pathogenesis or pandemic …

Sociodemographic, Clinical Characteristics, And Outcomes Of Influenza Pneumonia Patients Admitted In A Tertiary Care Hospital In Karachi, Pakistan: Findings From A Cross-Sectional Study, Fazal Ur Rehman, Muhammad Arslan Ahmed, Kashif Aziz, Mahmooda Jabeen Ashraf, Tazein Amber, Sumera Aziz Ali

Section of Internal Medicine

Objective: To determine the sociodemographic, clinical characteristics, and outcomes of influenza pneumonia patients in tertiary care hospital, Karachi Pakistan.
Study design: A cross-sectional study.
Place and duration of study: The Aga Khan University Hospital Karachi Pakistan from January 2013 to December 2018. Methodology: All adult patients who were older than 18 years and suspected to have viral pneumonia were included in the study. Data were abstracted on 105 patients and were entered on preformed proforma after reviewing the files of patients.
Results: Ninety-four (89.5%) patients were influenza positive and 15.2% (n=16) had been vaccinated. Around 92.4% (n=97), 81.9% (n=86) and …

Streptococcus Cristatus – An Oral Bacterium Causing A Case Of Mild Bacteremia And “Possible Endocarditis”, Camilo Guzman, Adi Zaclli, John Molinari

Medical Student Research Symposium

Streptococcus cristatus is a member of the Mitis streptococcus group. Like other members of this group, it resides in mucosal surfaces of the oral cavity but rarely causes disease. We present a case of S. cristatus bacteremia and “possible endocarditis” (per the modified Duke criteria) in a 59-year-old male suffering from end- stage cryptogenic cirrhosis. To date, it is the fifth reported case of disease caused by the microbe, and the first adult case in which S. cristatus was the sole microbe identified. Our patient had a history of dental caries and poor dentition, which were likely the source of …

Investigating Microbial And Host Factors That Modulate Severity Of Clostridioides Difficile Associated Disease, Armando Lerma

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Clostridioides difficile is recognized as one of the most important pathogens in hospital and community healthcare settings. The clinical outcome of infection of toxigenic C. difficile infection (CDI) ranges from asymptomatic colonization to fulminant pseudomembranous colitis and death. In recent studies, it has been suggested that a high proportion of nosocomial CDI cases are transmitted from asymptomatic carriers which might be acting as infection reservoirs. Understanding what causes the different responses to infection could lead to the development of novel prevention and treatment strategies. Although several explanations have been proposed to explain variations in susceptibility, understanding of the exact mechanisms …

Response Of Extensively Drug Resistant Salmonella Typhi To Treatment With Meropenem And Azithromycin, In Pakistan, Sonia Qureshi, Abdullah B. Naveed, Mohammad Tahir Yousafzai, Khalil Ahmad, Sarwat Ansari, Heeramani Lohana, Aiman Mukhtar, Farah Naz Qamar

Department of Paediatrics and Child Health

Introduction: Salmonella Typhi is one of the leading health problems in Pakistan. With the emergence of extensively drug resistant (XDR) Salmonella Typhi, treatment options are limited. Here we report the clinical manifestations and the response to treatment of patients with XDR Typhoid fever. The patients were treated with either Meropenem or Azithromycin or a combination of both.
Methods: We reviewed the records of culture confirmed XDR typhoid who visited Aga Khan University Hospital (AKUH), Karachi and Aga Khan Secondary Care Hospital, Hyderabad from April 2017 to June 2018. Symptoms developed during disease, unplanned treatment extension and complications developed while on …

A Race Against Time: Reduced Azithromycin Susceptibility In Salmonella Enterica Serovar Typhi In Pakistan, Junaid Iqbal, Irum Fatima Dehraj, Megan E. Carey, Zoe A. Dyson, Denise Garrett, Jessica C. Seidman, Furqan Kabir, Senjuti Saha, Stephen Baker, Farah Naz Qamar

Department of Paediatrics and Child Health

Antimicrobial resistance is an ongoing issue in the treatment of typhoid fever. Resistance to first-line antimicrobials and extensively drug resistant (XDR) Salmonella Typhi isolates in Pakistan have left azithromycin as the only remaining effective oral treatment. Here, we report the emergence of organisms with a single point mutation in acrB gene, implicated in azithromycin resistance, in a S. Typhi isolate from Pakistan. The isolation of this organism is worrisome and highlights the significance of the introduction of typhoid conjugate vaccine in South Asia.
Importance: The emergence of XDR Salmonella Typhi in Pakistan has left azithromycin as the only viable oral …

Chrysin‐Loaded Chitosan Nanoparticles Potentiates Antibiofilm Activity Against Staphylococcus Aureus, Busi Siddhardha, Uday Pandey, K. Kaviyarasu, Rajasekharreddy Pala, Asad Syed, Ali K. Bahkali, Abdallah M. Elgorban

Pharmacy Faculty Articles and Research

The application of nanotechnology in medicine is gaining popularity due to its ability to increase the bioavailability and biosorption of numerous drugs. Chrysin, a flavone constituent of Orocylumineicum vent is well‐reported for its biological properties. However, its therapeutic potential has not been fully exploited due to its poor solubility and bioavailability. In the present study, chrysin was encapsulated into chitosan nanoparticles using TPP as a linker. The nanoparticles were characterized and investigated for their anti‐biofilm activity against Staphylococcus aureus. At sub‐Minimum Inhibitory Concentration, the nanoparticles exhibited enhanced anti‐biofilm efficacy against S. aureus as compared to its bulk counterparts, chrysin …

Prevalence Of The Hypervirulent Nap1/Bi/027 Strain Of C. Difficile In Southwestern Virginia And Risk Factors Associated With Infection, Andrew O. Hanna, Anthony Baffoe-Bonnie, Shikha Vasudeva

Graduate Medical Education (GME) Resident and Fellow Research Day Posters

C. difficile infection (CDI) incidence has increased over the last several decades. The BI/NAP1/027 ribotype was discovered in 2005 and has since been responsible for multiple outbreaks in the US and Canada. This subtype of C. Difficile is known to be more virulent in vivo and produce more severe disease. Limited regional data of the prevalence of this ribotype is available, which could help guide treatment. Using infection control data from a large regional hospital and a VA medical center, this study documented the prevalence of the 027 ribotype in Southwest Virginia. Patients were included if they were tested at …

Community-Acquired Pneumonia In Adults: Diagnostic Reliability Of Physical Examination Techniques And Their Teaching In Academia, Amber Tordoff, Lauren A. Williams

Physician Assistant Capstones, 2016 to 2019

Background: Chest physical examination techniques are taught in academia, but their usefulness in the evaluation and diagnosis of patients in the clinical setting is controversial. Objective: To investigate the accuracy of physical examination techniques and their reliability in diagnosing community acquired pneumonia (CAP) and suggest a modified teaching approach to be used in academia. Design: Systematic Literature Review. Methods: Database search of PubMed and Google Scholar using the search terms “prediction of pneumonia in adults” and “prediction rule for pulmonary infiltrates.” Filters were implemented to include articles that only dealt with human subjects and were full text. Articles …

Nocardia Brasiliensis Infection After Hurricane Irma: Two Case Reports, Sarah Al-Obaydi Md, James Demaio, Nemer Dabage Md

Infectious Disease

Background: Although an increase in skin and soft tissue infections has been well documented after natural disasters, cases of Nocardia brasiliensis infection have not been included in prior reports. We present two cases of N. brasiliensis lymphadenitis that occurred in Manatee County, Florida after Hurricane Irma.

Methods: Case 1-A 75 year old immune competent male may have injured his arm while retrieving a golf ball approximately four weeks after Hurricane Irma. Ten days later he presented to the hospital with an abscess on his left forearm and a lymphadenitis extending nearly to the axilla. Despite treatment with vancomycin, the lymph …

Infections Not Fought: Antibiotic Resistance In Underserved Communities, Derek Lillestolen

Senior Honors Theses

In 1928, the profound effects of penicillin were discovered and antibiotic treatments became extremely popular. Broad-spectrum antibiotics, like tetracyclines, have been since branded as cure-all prescriptions and used profusely in the Western World and abroad. Due to ignorance of specific biochemical mechanisms and the misuse of antibiotics these drugs inadvertently allowed the rise in prevalence of antibiotic resistant strains of certain bacteria as the century progressed. Now, the specific genetic causes and mechanisms of antibiotic resistance are being understood, but the fight against antimicrobial resistance is far from over. In the United States, thousands of fatalities are caused annually by …

Lymphoid Hematopoiesis And The Role Of B-Cells In Transgenic Mouse Model Of Sickle Cell Disease, Christina Cotte

University Scholar Projects

Sickle cell disease (SCD) has been shown to be associated with decreased baseline immunity and thus increased susceptibility to infection. I sought to discern possible causes of this by looking into the correlations between SCD and hematopoiesis, the immune system and the neuroendocrine system, and ultimately by conducting experiments surrounding the impaired immune system of SCD. These experiments focused on the potential causes and effects of the diminution of B-1a cells in the SCD spleen. Adoptive transfers, infections with Streptococcus pneumoniae, and histologic imaging were conducted to establish if the diminution of the B-1a cells in the SCD spleen …

Changing Diagnostic Methods And Increased Detection Of Verotoxigenic Escherichia Coli, Ireland, Thomas Rice, Noreen Quinn, Roy D. Sleator, Brigid Lucey

Department of Biological Sciences Publications

The recent paradigm shift in infectious disease diagnosis from culture-based to molecular-based approaches is exemplified in the findings of a national study assessing the detection of verotoxigenic Escherichia coli infections in Ireland. The methodologic changes have been accompanied by a dramatic increase in detections of non-O157 verotoxigenic E. coli serotypes.

Effects Of Clostridium Difficile On The Human Immune Response, Mike Mcgovern

Honors Projects in Science and Technology

Clostridium difficile is a bacterium that is rapidly becoming a large issue in the medical community due to its tendency to infect hospital patients and its resistance to antibiotics. By studying the way in which the pathogen interacts with the human immune system, it is possible to better understand how the body naturally fights off the disease. This knowledge can allow medical professionals to develop treatments that can help curtail the infection before serious symptoms occur. Working under a grant program alongside Professors Kirsten Hokeness and Chris Reid, I was able to research the effects that exposure to the C. …

Pseudomonas Aeruginosa Ampr Transcriptional Regulatory Network, Deepak Balasubramanian

FIU Electronic Theses and Dissertations

In Enterobacteriaceae, the transcriptional regulator AmpR, a member of the LysR family, regulates the expression of a chromosomal β-lactamase AmpC. The regulatory repertoire of AmpR is broader in Pseudomonas aeruginosa, an opportunistic pathogen responsible for numerous acute and chronic infections including cystic fibrosis. Previous studies showed that in addition to regulating ampC, P. aeruginosa AmpR regulates the sigma factor AlgT/U and production of some quorum sensing (QS)-regulated virulence factors. In order to better understand the ampR regulon, the transcriptional profiles generated using DNA microarrays and RNA-Seq of the prototypic P. aeruginosa PAO1 strain with its isogenic ampR deletion …