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Safdar, Nasia

https://orcid.org/0000-0003-3946-0437

Mayo Clinic

University of Wisconsin–Madison

Citations 9

Prevention of recurrent Clostridioides difficile infection by fecal microbiota, live-jslm (REBYOTA ® ) administered via colonoscopy: 6-month data from the sin
Khanna, Sahil , Yoho, David, Handel, Daniel Van, Clark, Brian J., Guthmueller, Beth, Armandi, Daniel, Knapple, W , Safdar, Nasia , Baggott, Brian, Simon, Karen, Knapple, Whitfield , Feuerstadt, Paul , Awad, Tahany , Feuerstadt, Paul

Therapeutic Advances in Gastroenterology | November 10, 2025 | Volume: 18 | Issue: No issue available | Pages: No page available

10.1177/17562848251396744 Get It

Background: Fecal microbiota, live-jslm (RBL) is a microbiota-based product for the prevention of recurrent Clostridioides difficile infection (rCDI) in adults following antibiotic treatment. The safety and clinical effectiveness of RBL administered via colonoscopy in adults with rCDI were evaluated in CDI-SCOPE. An 8-week analysis showed 9.8% of participants had RBL-related treatment-emergent adverse events (TEAEs; primary endpoint) and 95.1% experienced treatment success (no CDI recurrence). Objectives: To evaluate long-term safety and clinical effectiveness of RBL through 6 months of follow-up in CDI-SCOPE. Design: Single-arm exploratory phase IIIb trial conducted at 12 sites in the United States. Methods: Eligible adults with rCDI received a single 150-mL dose of RBL to the right colon via colonoscopy. The primary endpoint was RBL-related TEAEs through 8 weeks after RBL administration or confirmed treatment failure. Secondary endpoints included safety up to 6 months after RBL administration. Exploratory analyses included assessment of further CDI episodes. Results: Of the 41 participants enrolled, 39 completed trial assessments through 6 months. From 8 weeks through 6 months after RBL administration, 36 TEAEs in 15 participants (36.6%) were reported, one of which (irritable bowel syndrome) was RBL-related; most TEAEs (97.2%) were of mild or moderate severity. Over the 6-month trial period, 23 participants (56.1%) experienced 69 TEAEs; 94.2% were of mild or moderate severity. Serious TEAEs occurred in three participants (7.3%), none of which were related to RBL or its administration, and no TEAEs led to discontinuation or death. Overall, 38 participants (92.7%) did not experience further CDI episodes, 1 (2.4%) did between 8 weeks and 6 months, and 2 (4.9%) had an indeterminate outcome due to trial withdrawal before 8 weeks. Conclusion: RBL administered via colonoscopy was safe and effective for preventing CDI recurrence in adults with rCDI in CDI-SCOPE. Trial registration: ClinicalTrials.gov: NCT05831189.
Oral Vancomycin for Prevention of Recurrent Clostridioides difficile Infection
Keating, Julie A. , Xu, Tinghui , Graham, Mary Beth, Ramesh, Mayur , Khanna, Sahil , Dixon, Jonah, Haight, Kendra , Zhao, Jiwei , Safdar, Nasia , Kates, Ashley , Saddler, Christopher M.

JAMA Network Open | July 2, 2025 | Volume: 8 | Issue: 7 | Pages: e2517834

10.1001/jamanetworkopen.2025.17834 Get It

ImportanceSystemic antibiotic use for patients with a non–Clostridioides difficile infection (CDI) is a major risk factor for recurrent CDI. Increasing use of oral vancomycin for secondary prophylaxis against recurrent CDI in this context has uncertain efficacy.ObjectiveTo evaluate whether oral vancomycin prophylaxis compared with placebo is effective against recurrent CDI during and 8 weeks after the end of study treatment.Design, Setting, and ParticipantsThis phase 2, placebo-controlled, double-blind randomized clinical trial was conducted in 4 large health systems across the upper Midwest US. Adults who had completed treatment for CDI within the past 180 days and were taking a systemic antibiotic for a non-CDI indication were enrolled between May 21, 2018, and March 30, 2023, and followed up for 8 weeks after the end of study treatment.InterventionParticipants were randomized 1:1 to 125 mg of oral vancomycin or placebo once daily during antibiotic use for a non-CDI plus 5 days following cessation of those antibiotics.Main Outcomes and MeasuresThe primary outcome was recurrent CDI incidence during treatment and the 8-week follow-up period. The secondary outcome was vancomycin-resistant Enterococcus carriage in stool.ResultsAmong 81 randomized participants (median age, 59 years [IQR, 50-67 years]), all were included in the primary as-randomized analysis (39 in the vancomycin group; 42 in the placebo group). Sixty patients (74.1%) completed 8-week follow-up and were included in the secondary as–completed treatment analysis (31 in the vancomycin group; 29 in the placebo group). Recurrent CDI occurred in 17 of 39 participants in the oral vancomycin group (43.6%) and 24 of 42 in the placebo group (57.1%; absolute difference in percentage, −13.5% [95% CI, −35.1% to 8.0%]). Adverse events occurred in 27 of 39 participants in the oral vancomycin group (69.2%) and 27 of 42 in the placebo group (64.3%). Vancomycin-resistant Enterococcus carriage was found in 15 of 30 patients in the oral vancomycin group (50.0%) and 6 of 25 in the placebo group (24.0%) (P = .048) 8 weeks after treatment.Conclusions and RelevanceIn this randomized clinical trial, the incidence of recurrent CDI was lower (though did not reach significance) in participants taking oral vancomycin compared with those taking placebo. Because the study was underpowered, it was unable to reveal firm conclusions about the efficacy (or lack thereof) of vancomycin prophylaxis with respect to recurrent CDI.Trial RegistrationClinicalTrials.gov Identifier: NCT03462459
Safety and effectiveness of fecal microbiota, live-jslm (REBYOTA ® ) administered by colonoscopy for prevention of recurrent Clostridioides difficile infectio
Khanna, Sahil , Yoho, David, Handel, Daniel Van, Clark, Brian J., Awad, Tahany , Guthmueller, Beth, Armandi, Daniel, Knapple, W , Safdar, Nasia , Baggott, Brian, Simon, Karen, Knapple, Whitfield , Feuerstadt, Paul , Feuerstadt, Paul

Therapeutic Advances in Gastroenterology | April 23, 2025 | Volume: 18 | Issue: No issue available | Pages: No page available

10.1177/17562848251339697 Get It

Background: Recurrent Clostridioides difficile infection (rCDI) occurs in up to 35% of patients with CDI, and further recurrence is common. Fecal microbiota, live-jslm (RBL) is safe and effective for preventing rCDI in adults following antibiotic treatment for rCDI when administered rectally. There is clinical interest in alternative routes of administration. Objectives: CDI-SCOPE assessed the safety and clinical effectiveness of RBL when administered via colonoscopy to adults with rCDI. Design: Single-arm, exploratory phase IIIb trial conducted at 12 sites in the United States. Methods: Eligible adults with rCDI received one administration of RBL consisting of one 150-mL dose of RBL, delivered via colonoscopy to the right side of the colon. The primary endpoint assessed RBL-related treatment-emergent adverse events (TEAEs) within 8 weeks of RBL administration or until confirmed treatment failure. Secondary endpoints included treatment success (absence of CDI recurrence for 8 weeks following RBL administration), physician experience administering RBL via colonoscopy, and physician perception of participant benefit. Results: Of 54 participants screened, 41 were enrolled and received RBL via colonoscopy; 39 participants completed the 8-week visit. Five TEAEs in four participants (9.8%) were assessed as related to RBL, all of which were gastrointestinal and mild in severity. Overall, 18 participants (43.9%) experienced 33 TEAEs within 8 weeks, most of which were of mild (25/33; 75.8%) or moderate (5/33; 15.2%) severity. No TEAEs led to intensive care unit admission or death. Overall, 39 participants (95.1%) experienced treatment success; 2 participants (4.9%) withdrew consent and had an indeterminate outcome. Among physicians, 90.2% of investigators indicated a “positive” or “very positive” experience administering RBL by colonoscopy. All physicians assessed participant benefit as “much” or “very much” improved. Conclusion: This single-arm study suggests RBL administered via colonoscopy is practical, safe, and effective for preventing CDI recurrence following antibiotic treatment in adults. Trial registration: ClinicalTrials.gov: NCT05831189.
Comparing Complication Rates of Midline Catheter vs Peripherally Inserted Central Catheter. A Systematic Review and Meta-analysis
Urtecho, Meritxell , Roldan, Victor D. Torres , Nayfeh, Tarek , Ranganath, Nischal , Sampathkumar, Priya , Safdar, Nasia , Torres Roldan, Victor D , Ranganath, Nischal , Nayfeh, Tarek , Suárez, Nataly R. Espinoza , Chopra, Vineet , Prokop, Larry J. , O’Horo, John C.

Open Forum Infectious Diseases | January 18, 2023 | Volume: 10 | Issue: 2 | Pages: No page available

10.1093/ofid/ofad024 Get It

Abstract Background Peripherally inserted central catheters (PICCs) and midlines are commonly used devices for reliable vascular access. Infection and thrombosis are the main adverse effects of these catheters. We aimed to evaluate the relative risk of complications from midlines and PICCs. Methods We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and observational studies. The primary outcomes were catheter-related bloodstream infection (CRBSI) and thrombosis. Secondary outcomes evaluated included mortality, failure to complete therapy, catheter occlusion, phlebitis, and catheter fracture. The certainty of evidence was assessed using the GRADE approach. Results Of 8368 citations identified, 20 studies met the eligibility criteria, including 1 RCT and 19 observational studies. Midline use was associated with fewer patients with CRBSI compared with PICCs (odds ratio [OR], 0.24; 95% CI, 0.15–0.38). This association was not observed when we evaluated risk per catheter. No significant association was found between catheters when evaluating risk of localized thrombosis and pulmonary embolism. A subgroup analysis based on location of thrombosis showed higher rates of superficial venous thrombosis in patients using midlines (OR, 2.30; 95% CI, 1.48–3.57). We did not identify any significant difference between midlines and PICCs for the secondary outcomes. Conclusions Our findings suggest that patients who use midlines might experience fewer CRBSIs than those who use PICCs. However, the use of midline catheters was associated with greater risk of superficial vein thrombosis. These findings can help guide future cost-benefit analyses and direct comparative RCTs to further characterize the efficacy and risks of PICCs vs midline catheters.
The role of the gut microbiome in colonization resistance and recurrent Clostridioides difficile infection
Safdar, Nasia , Khanna, Sahil , Khanna, S , Seekatz, Anna Maria

Therapeutic Advances in Gastroenterology | November 19, 2022 | Volume: 15 | Issue: No issue available | Pages: No page available

10.1177/17562848221134396 Get It

The species composition of the human gut microbiota is related to overall health, and a healthy gut microbiome is crucial in maintaining colonization resistance against pathogens. Disruption of gut microbiome composition and functionality reduces colonization resistance and has been associated with several gastrointestinal and non-gastrointestinal diseases. One prime example is Clostridioides difficile infection (CDI) and subsequent recurrent infections that occur after the development of systemic antibiotic-related dysbiosis. Standard-of-care antibiotics used for both acute and recurrent infections do not address dysbiosis and often worsen the condition. Moreover, monoclonal antibodies, recommended in conjunction with standard-of-care antibiotics for the prevention of recurrent CDI in patients at high risk of recurrence, reduce recurrences but do not address the underlying dysbiosis. Fecal microbiota transplantation (FMT) is an evolving therapeutic strategy in which microbes are harvested from healthy donor stool and transplanted into the gut of a recipient to restore the gut microbiome. Although effective in the prevention of recurrent CDI, some existing challenges include screening and the standardization of stool acquisition and processing. Recent safety alerts by the US Food and Drug Administration raised concern about the possibility of transmission of multidrug-resistant organisms or severe acute respiratory syndrome coronavirus 2 via FMT. Increased knowledge that microbes are beneficial in restoring the gut microbiome has led to the clinical development of several newer biotherapeutic formulations that are more regulated than FMT, which may allow for improved restoration of the gut microbiome and prevention of CDI recurrence. This review focuses on mechanisms by which gut microbiome restoration could influence colonization resistance against the pathogen C. difficile. Plain language summary The Role of the Gut Microbiome in Clostridioides difficile Infection Introduction: A rich and diverse gut microbiome is key to immune system regulation and colonization resistance against pathogens. A disruption in the gut microbiome composition can make the gut more vulnerable to diseases such as Clostridioides difficile infection (CDI), caused by the bacterium C. difficile. CDI management presents a therapeutic dilemma, as it is usually treated with antibiotics that can treat the infection but also can damage the microbiome. Treatment of CDI using antibiotics can further reduce microbial diversity and deplete beneficial bacteria from the gut leading to a condition called dysbiosis. Antibiotic treatment can be followed by therapies that restore the gut microbiota, boost colonization resistance, and prevent the development of antimicrobial resistance. It is important to evaluate treatment options to determine their safety and effectiveness. Methods: The researchers provided an overview of the mechanisms that the gut microbiome uses to prevent colonization of the gut by pathogens. They subsequently reviewed the efficacy and shortcomings of the following treatments for CDI: - Antibiotics - Monoclonal antibodies - Fecal microbiota transplantation (FMT) Results: Commensal intestinal bacteria prevent colonization of the gut by pathogens using mechanisms such as: - Competition for key nutrients - Production of inhibitory bile acids - Short-chain fatty acid production - Lowering the luminal pH - Production of bacteriocins Antibiotic therapy is recommended as a standard treatment for CDI. However, patients are vulnerable to recurrent CDI after discontinuation of the therapy. Monoclonal antibodies that inactivate C. difficile toxins may be recommended along with antibiotics to prevent recurrent CDI. However, this approach does not restore the microbiome. FMT is one method of microbial restoration, where stool is harvested from a healthy donor and transplanted into a patient’s colon. Although FMT has shown some efficacy in the treatment of recurrent CDI, the procedure is not standardized. Safety concerns have been raised about the possibility of transmission of multidrug-resistant pathogens via FMT. Conclusion: Treatment methods that can efficiently restore the diversity of the gut microbiome are crucial in preventing recurrence of CDI.
Evolution of a globally unique SARS-CoV-2 Spike E484T monoclonal antibody escape mutation in a persistently infected, immunocompromised individual
Halfmann, Peter , Minor, Nicholas R. , Haddock, Luis A. , Maddox, Robert James, Riemersa, Kasen K., Prasad, A. Mallikarjuna, Alman, Kirsten J., Florek, Kelsey R. , Bateman, Allen , Safdar, Nasia , Andes, David R. , Kawaoka, Yoshihiro , Yao, Joseph D. , O’Connor, David H. , Halfmann, Peter J , Haddock Iii, Luis A , Florek, Kelsey , O'Connor, David H , Maddox, Robert, Moreno, Gage K. , Braun, Katarina M. , Baker, David , Prasad, Ankur, Lambert, Matthew C, Westergaard, Ryan P. , Fida, Madiha , Friedrich, Thomas C.

Virus Evolution | November 5, 2022 | Volume: 9 | Issue: 2 | Pages: No page available

10.1093/ve/veac104 Get It

Abstract Prolonged infections in immunocompromised individuals may be a source for novel Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants, particularly when both the immune system and antiviral therapy fail to clear the infection and enable within-host evolution. Here we describe a 486-day case of SARS-CoV-2 infection in an immunocompromised individual. Following monotherapy with the monoclonal antibody Bamlanivimab, the individual’s virus acquired resistance, likely via the earliest known occurrence of Spike amino acid variant E484T. Recently, E484T has arisen again as a derivative of E484A in the Omicron Variant of Concern, supporting the hypothesis that prolonged infections can give rise to novel variants long before they become prevalent in the human population.
Implementation of an antibiotic stewardship intervention to reduce prescription of fluoroquinolones: A human factors analysis in two intensive care units
Carayon, Pascale , Thuemling, Teresa, Parmasad, Vishala , Bao, Songtao, Bennett, Nicholas , Safdar, Nasia , O'horo, John, O’Horo, John C.

Journal of Patient Safety and Risk Management | June 22, 2021 | Volume: 26 | Issue: 4 | Pages: 161-171

10.1177/25160435211025417 Get It

Antibiotic use is often the target of interventions in health care organizations that aim to decrease healthcare-associated infections (HAI) such as Clostridioides difficile (CDI); this is particularly important for fluoroquinolones (FQ), which are frequently used in critical care settings. In this study, using a multiple case study research approach, we conduct an in-depth analysis of an intervention aimed at limiting ICU prescriber access to FQ in two ICUs of two hospitals. The data collection and analysis were guided by a human factors engineering approach based on the SEIPS (Systems Engineering Initiative for Patient Safety) model and evidence-based implementation principles. Our results show some differences in the implementation of the FQ intervention between the two ICUs, such as level and method of FQ restriction, and training and communication with physicians and pharmacists. In both ICUs, several organizational learning mechanisms helped to quickly identify problems with the intervention and ensure that changes were made in a just-in-time manner (e.g. just-in-time training, removal of FQ in order set for pneumonia). Despite their organizational differences, both sites developed strategies to successfully implement the FQ intervention.
The epidemiology and outcomes of invasive Candida infections among organ transplant recipients in the United States: results of the Transplant‐Associated Infection Surveillance Network (TRANSNET)
Andes, David R. , Safdar, Nasia , Alexander, Barbara D. , Brumble, Lisa , Freifeld, Allison, Hadley, Susan , Herwaldt, Loreen A. , Kauffman, Carol A., Lyon, G. Marshall, Morrison, Vicki A., Perl, Trish M. , Walker, Randall C., Hess, Tim, Chiller, Tom , Pappas, Peter G. , Investigators, The TRANSNET, Walker, Randall, Baddley, John W. , Patterson, Thomas F. , Investigators, The TRANSNET

Transplant Infectious Disease | September 19, 2016 | Volume: 18 | Issue: 6 | Pages: 921-931

10.1111/tid.12613 Get It

AbstractBackgroundInvasive candidiasis (IC) is a common cause of mortality in solid organ transplant recipients (OTRs), but knowledge of epidemiology in this population is limited.MethodThe present analysis describes data from 15 US centers that prospectively identified IC from nearly 17 000 OTRs. Analyses were undertaken to determine predictors of infection and mortality.ResultsA total of 639 cases of IC were identified. The most common species was Candida albicans (46.3%), followed by Candida glabrata (24.4%) and Candida parapsilosis (8.1%). In 68 cases >1 species was identified. The most common infection site was bloodstream (44%), followed by intra‐abdominal (14%). The most frequently affected allograft groups were liver (41.1%) and kidney (35.3%). All‐cause mortality at 90 days was 26.5% for all species and was highest for Candida tropicalis (44%) and C. parapsilosis (35.2%). Non‐white race and female gender were more commonly associated with non‐albicans species. A high rate of breakthrough IC was seen in patients receiving antifungal prophylaxis (39%). Factors associated with mortality include organ dysfunction, lung transplant, and treatment with a polyene antifungal. The only modifiable factor identified was choice of antifungal drug class based upon infecting Candida species.ConclusionThese data highlight the common and distinct features of IC in OTRs.
Bedside diagnosis of dysphagia: A systematic review
O’Horo, John C. , Rogus‐Pulia, Nicole , Garcia‐Arguello, Lisbeth, Robbins, JoAnne, Safdar, Nasia , Garcia-Arguello, Lisbeth, O'Horo, John C

Journal of Hospital Medicine | January 12, 2015 | Volume: 10 | Issue: 4 | Pages: 256-265

10.1002/jhm.2313 Get It

Dysphagia is associated with aspiration, pneumonia, and malnutrition, but remains challenging to identify at the bedside. A variety of exam protocols and maneuvers are commonly used, but the efficacy of these maneuvers is highly variable. We conducted a comprehensive search of 7 databases, including MEDLINE, Embase, and Scopus, from each database's earliest inception through June 9, 2014. Studies reporting diagnostic performance of a bedside examination maneuver compared to a reference gold standard (videofluoroscopic swallow study or flexible endoscopic evaluation of swallowing with sensory testing) were included for analysis. From each study, data were abstracted based on the type of diagnostic method and reference standard study population and inclusion/exclusion characteristics, design, and prediction of aspiration. The search strategy identified 38 articles meeting inclusion criteria. Overall, most bedside examinations lacked sufficient sensitivity to be used for screening purposes across all patient populations examined. Individual studies found dysphonia assessments, abnormal pharyngeal sensation assessments, dual axis accelerometry, and 1 description of water swallow testing to be sensitive tools, but none were reported as consistently sensitive. A preponderance of identified studies was in poststroke adults, limiting the generalizability of results. No bedside screening protocol has been shown to provide adequate predictive value for presence of aspiration. Several individual exam maneuvers demonstrated reasonable sensitivity, but reproducibility and consistency of these protocols was not established. More research is needed to design an optimal protocol for dysphagia detection. Journal of Hospital Medicine 2015;10:256–265. © 2015 Society of Hospital Medicine