Effect of Citizenship Status on Access to Pediatric Liver and Kidney Transplantation.

Transplantation of non-US citizen residents remains controversial. We evaluate national trends in transplant activity amongst pediatric non-citizen residents (PNCR). Pediatric liver and kidney transplant data were obtained from the Organ Procurement and Transplantation Network and Scientific Registry of Transplant Recipients. Data on transplanted organs, region, waitlist additions, procedures, and citizenship status were analyzed from 2012-2022. Rates of PNCR transplantation activity were compared with population rates from the US Census Bureau. On average, 713±47 pediatric liver and 1039±51 kidney patients were added to the waitlist, with 544±32 liver and 742±33 kidney transplants performed annually. Of these, PNCR comprised 1.5% and 3.3% of liver and kidney waitlist additions, and 1.5% and 2.9% of liver and kidney transplant procedures, respectively. There were no significant changes in waitlist or transplant activity nationwide over the study period. There was significant geographic variation in the percentage of waitlist additions and transplants across United Network for Organ Sharing regions amongst PNCR for liver and kidney transplantation. This is the first study to evaluate national trends in transplantation activity amongst PNCR. The significant regional variation in transplantation activity for PNCR may suggest multilevel structural and systemic barriers to transplant accessibility.

A simple solid media assay for detection of synergy between bacteriophages and antibiotics.

The emergence of antibiotic-resistant bacteria (ARB) has necessitated the development of alternative therapies to deal with this global threat. Bacteriophages (viruses that target bacteria) that kill ARB are one such alternative. Although phages have been used clinically for decades with inconsistent results, a number of recent advances in phage selection, propagation, and purification have enabled a reevaluation of their utility in contemporary clinical medicine. In most phage therapy cases, phages are administered in combination with antibiotics to ensure that patients receive the standard-of-care treatment. Some phages may work cooperatively with antibiotics to eradicate ARB, as often determined using non-standardized broth assays. We sought to develop a solid media-based assay to assess cooperativity between antibiotics and phages to offer a standardized platform for such testing. We modeled the interactions that occur between antibiotics and phages on solid medium to measure additive, antagonistic, and synergistic interactions. We then tested the method using different bacterial isolates and identified a number of isolates where synergistic interactions were identified. These interactions were not dependent on the specific organism, phage family, or antibiotic used. A priori susceptibility to the antibiotic or the specific phage were not requirements to observe synergistic interactions. Our data also confirm the potential for the restoration of vancomycin to treat vancomycin-resistant Enterococcus (VRE) when used in combination with phages. Solid media assays for the detection of cooperative interactions between antibiotics and phages can be an accessible technique adopted by clinical laboratories to evaluate antibiotic and phage choices in phage therapy.IMPORTANCEBacteriophages have become an important alternative treatment for individuals with life-threatening antibiotic-resistant bacteria (ARB) infections. Because antibiotics represent the standard-of-care for treatment of ARB, antibiotics and phages often are delivered together without evidence that they work cooperatively. Testing for cooperativity can be difficult due to the equipment necessary and a lack of standardized means for performing the testing in liquid medium. We developed an assay using solid medium to identify interactions between antibiotics and phages for gram-positive and gram-negative bacteria. We modeled the interactions between antibiotics and phages on solid medium, and then tested multiple replicates of vancomycin-resistant Enterococcus (VRE) and Stenotrophomonas in the assay. For each organism, we identified synergy between different phage and antibiotic combinations. The development of this solid media assay for assessing synergy between phages and antibiotics will better inform the use of these combinations in the treatment of ARB infections.

Association of LDL-cholesterol <1.8 mmol/L and statin use with the recurrence of intracerebral hemorrhage.

BACKGROUND: Recent intensive low-density lipoprotein cholesterol (LDL-C) lowering trials, including FOURIER, ODYSSEY OUTCOMES, and Treat Stroke to Target (TST) trials, have mostly refuted the concern surrounding statin use, LDL-C lowering, and intracerebral hemorrhage (ICH) risk. However, the results from these trials may not be fully applied to ICH survivors, as the populations studied were mainly patients without prior ICH, in whom the inherent ICH risk is more than 10 times lower than that of ICH survivors. Although available literature on statin use after ICH has demonstrated no excess risk of recurrent ICH, other potential factors that may modify ICH risk, especially hypertension control and ICH etiology, have not generally been considered. Notably, data on LDL-C levels following ICH are lacking. AIMS: We aim to investigate the association between LDL-C levels and statin use with ICH risk among ICH survivors, and to determine whether the risk differed with patients' characteristics, especially ICH etiology. METHODS: Follow-up data of consecutive spontaneous ICH survivors enrolled in the University of Hong Kong prospective stroke registry from 2011 to 2019 were retrospectively analyzed. ICH etiology was classified as cerebral amyloid angiopathy (CAA) using the modified Boston criteria or hypertensive arteriopathy, while the mean follow-up LDL-C value was categorized as <1.8 or ⩾1.8 mmol/L. The primary endpoint was recurrent ICH. The association of LDL-C level and statin use with recurrent ICH was determined using multivariable Cox regression. Pre-specified subgroup analyses were performed, including based on ICH etiology and statin prescription. Follow-up blood pressure was included in all the regression models. RESULTS: In 502 ICH survivors (mean age = 64.2 ± 13.5 years, mean follow-up LDL-C = 2.2 ± 0.6 mmol/L, 28% with LDL-C <1.8 mmol/L), 44 had ICH recurrence during a mean follow-up of 5.9 ± 2.8 years. Statin use after ICH was not associated with recurrent ICH (adjusted hazard ratio (AHR) = 1.07, 95% confidence interval (CI) = 0.57-2.00). The risk of ICH recurrence was increased for follow-up LDL-C <1.8 mmol/L (AHR = 1.99, 95% CI = 1.06-3.73). This association was predominantly observed in ICH attributable to CAA (AHR = 2.52, 95% CI = 1.06-5.99) and non-statin users (AHR = 2.91, 95% CI = 1.08-7.86). CONCLUSION: The association between post-ICH LDL-C <1.8 mmol/L and recurrent ICH was predominantly observed in CAA patients and those with intrinsically low LDL-C (non-statin users). While statins can be safely prescribed in ICH survivors, LDL-C targets should be individualized and caution must be exercised in CAA patients.

Universal Digital High-Resolution Melt Analysis for the Diagnosis of Bacteremia.

Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires approximately 15 hours to detect the presence of a pathogen. We, therefore, assessed the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 17 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 88% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1-mL sample input and sample-to-answer time of 6 hours. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection.

Metastatic pulmonary calcifications after pediatric liver transplantation.

BACKGROUND: Pulmonary calcification (PC) is a rare clinical entity observed following liver transplantation (LT). Most often identified in adults or in patients with concomitant renal failure, PC is rarely reported in children. While the clinical course of PC is largely benign, cases of progressive respiratory failure and death have been reported. Additionally, PC may mimic several other disease processes making diagnosis and management challenging. Currently, little is reported regarding the diagnosis, management, and long-term outcomes of children with PC following LT. METHODS: We performed a retrospective chart review of patients undergoing LT at our institution between 2006 and 2023. We identified two patients who developed PC following LT. Their diagnosis, clinical course, and long-term outcomes are reported. A literature review of the presentation, diagnosis, management, and outcomes of adult and pediatric patients with PC post-LT was also performed. CONCLUSIONS: Pulmonary calcifications are a rare but notable complication after pediatric liver transplantation. Our case series adds to the limited literature on this clinical entity in children but also highlights the fact that effective diagnosis and treatment may be safely accomplished without the use of lung biopsy.

Jumbo phages are active against extensively drug-resistant eyedrop-associated Pseudomonas aeruginosa infections.

Antibiotic-resistant bacteria present an emerging challenge to human health. Their prevalence has been increasing across the globe due in part to the liberal use of antibiotics that has pressured them to develop resistance. Those bacteria that acquire mobile genetic elements are especially concerning because those plasmids may be shared readily with other microbes that can then also become antibiotic resistant. Serious infections have recently been related to the contamination of preservative-free eyedrops with extensively drug-resistant (XDR) isolates of Pseudomonas aeruginosa, already resulting in three deaths. These drug-resistant isolates cannot be managed with most conventional antibiotics. We sought to identify alternatives to conventional antibiotics for the lysis of these XDR isolates and identified multiple bacteriophages (viruses that attack bacteria) that killed them efficiently. We found both jumbo phages (>200 kb in genome size) and non-jumbo phages that were active against these isolates, the former killing more efficiently. Jumbo phages effectively killed the three separate XDR P. aeruginosa isolates both on solid and liquid medium. Given the ongoing nature of the XDR P. aeruginosa eyedrop outbreak, the identification of phages active against them provides physicians with several novel potential alternatives for treatment.

Universal digital high resolution melt analysis for the diagnosis of bacteremia.

Fast and accurate diagnosis of bloodstream infection is necessary to inform treatment decisions for septic patients, who face hourly increases in mortality risk. Blood culture remains the gold standard test but typically requires ∼15 hours to detect the presence of a pathogen. Here, we assess the potential for universal digital high-resolution melt (U-dHRM) analysis to accomplish faster broad-based bacterial detection, load quantification, and species-level identification directly from whole blood. Analytical validation studies demonstrated strong agreement between U-dHRM load measurement and quantitative blood culture, indicating that U-dHRM detection is highly specific to intact organisms. In a pilot clinical study of 21 whole blood samples from pediatric patients undergoing simultaneous blood culture testing, U-dHRM achieved 100% concordance when compared with blood culture and 90.5% concordance when compared with clinical adjudication. Moreover, U-dHRM identified the causative pathogen to the species level in all cases where the organism was represented in the melt curve database. These results were achieved with a 1 mL sample input and sample-to-answer time of 6 hrs. Overall, this pilot study suggests that U-dHRM may be a promising method to address the challenges of quickly and accurately diagnosing a bloodstream infection. Universal digital high resolution melt analysis for the diagnosis of bacteremia: April Aralar, Tyler Goshia, Nanda Ramchandar, Shelley M. Lawrence, Aparajita Karmakar, Ankit Sharma, Mridu Sinha, David Pride, Peiting Kuo, Khrissa Lecrone, Megan Chiu, Karen Mestan, Eniko Sajti, Michelle Vanderpool, Sarah Lazar, Melanie Crabtree, Yordanos Tesfai, Stephanie I. Fraley.

A simple solid media assay for detection of synergy between bacteriophages and antibiotics.

The emergence of antibiotic resistant bacteria (ARB) has necessitated the development of alternative therapies to deal with this global threat. Bacteriophages (viruses that target bacteria) that kill ARB are one such alternative. While phages have been used clinically for decades with inconsistent results, a number of recent advances in phage selection, propagation and purification have enabled a reevaluation of their utility in contemporary clinical medicine. In most phage therapy cases, phages are administered in combination with antibiotics to ensure that patients receive the standard-of-care treatment. Some phages may work cooperatively with antibiotics to eradicate ARB, as often determined using non-standardized broth assays. We sought to develop a solid media-based assay to assess cooperativity between antibiotics and phages to offer a standardized platform for such testing. We modeled the interactions that occur between antibiotics and phages on solid medium to measure additive, antagonistic, and synergistic interactions. We then tested the method using different bacterial isolates, and identified a number of isolates where synergistic interactions were identified. These interactions were not dependent on the specific organism, phage family, or antibiotic used. A priori susceptibility to the antibiotic or the specific phage were not requirements to observe synergistic interactions. Our data also confirm the potential for the restoration of vancomycin to treat Vancomycin Resistant Enterococcus (VRE) when used in combination with phages. Solid media assays for the detection of cooperative interactions between antibiotics and phages can be an accessible technique adopted by clinical laboratories to evaluate antibiotic and phage choices in phage therapy.

Analysis of the FAST™ system for expedited identification and antimicrobial susceptibility testing of bloodborne pathogens.

The high morbidity and mortality of sepsis can be impacted by expediting identification (ID) and antibiotic susceptibility testing (AST) of causative bacteria. We evaluated the Qvella FAST™ System which creates a Liquid Colony™ (LC) from blood cultures that can be used to expedite results by 24 to 48 hours. We analyzed 289 LC samples and found that there were 17 (5.9%) that resulted in no ID. One hundred percent of the LC samples that produced an ID were concordant with SOC identification. Gram-positive bacteria showed a categorical agreement (CA) of 99.5%, with 3 minor errors (minE), and no major errors (majE) or very major errors (VME), and essential agreement (EA) of 98.9%. For Gram-negatives, the CA was 97.8% and the EA was 98.5% with 31 minE, 0 majE, and 2 VME. The FAST-System™ can accelerate ID and AST by 24 to 48 hours with potential positive impacts on time to effective therapy for sepsis.

Comparison of the APAS Independence Automated Plate Reader System with the Manual Standard of Care for Processing Urine Culture Specimens.

Urine cultures are among the highest-volume tests in clinical microbiology laboratories and usually require considerable manual labor to perform. We evaluated the APAS Independence automated plate reader system and compared it to our manual standard of care (SOC) for processing urine cultures. The APAS device provides automated image interpretation of urine culture plate growth and sorts those images that require further evaluation. We examined 1,519 specimens over a 4-month period and compared the APAS growth interpretations to our SOC. We found that 72 of the 1,519 total specimens (4.74%) had growth discrepancies, where these specimens were interpreted differently by the APAS and the technologist, which required additional evaluation of plate images on the APAS system. Overall, there were 56 discrepancies in pathogen identification, which were present in 3.69% of the cultures. An additional pathogen was uncovered in a majority of these discrepancies; 12 (21.4%) identified an additional pathogen for the SOC, and 40 (71.4%) identified an additional pathogen for the APAS workflow. We found 214 (2.69%) antimicrobial susceptibility test (AST) discrepancies; 136 (1.71%) minor errors (mEs), 41 (0.52%) major errors (MEs), and 36 (0.45%) very major errors (VMEs). Many of the MEs and VMEs occurred in only a small subset of 13 organisms, suggesting that the specimen may have had different strains of the same pathogens with differing AST results. Given the significant labor required to perform urine cultures, the APAS Independence system has the potential to reduce manual labor while maintaining the identity and AST results of urinary pathogens. IMPORTANCE Urine cultures are among the highest-volume tests performed in clinical microbiology facilities and require considerable manual labor to perform. We compared the results of our manual SOC workflow with that of the APAS Independence system, which provides automated image interpretation and sorting of urine culture plates based on growth. We examined 1,519 urine cultures processed using both workflows and found that only 4.74% had growth pattern discrepancies and 3.69% pathogen identification discrepancies. There was substantial agreement in AST results between workflows, with only 2.69% having discrepancies. Only 1.71% of the ASTs had mEs, 0.52% had MEs, and 0.45% had VMEs, with most of the MEs and VMEs belonging to a small subset of organisms. The APAS system significantly decreased manual urine culture processing, while providing similar results to the SOC. As such, incorporating such automation into laboratory workflows has the potential to significantly improve efficiency.

Student-led curricular approaches in medical education: the educational effects of a virtual fundamentals of COVID-19 course.

BACKGROUND: As the field of education was adapting to virtual learning during the COVID-19 pandemic, a need quickly emerged for a course to prepare medical students for future clinical practice. This call to action was answered by creating an innovative Fundamentals of COVID-19 course at the Indiana University School of Medicine (IUSM). As a group of medical student leaders at IUSM, we developed this online course in order to support our fellow students and the community. METHODS: The study examined the educational effects of completing the Fundamentals of COVID-19 course. In order to examine these effects, the study asked enrolled students to complete both a pre- and post-course self-assessment survey. Students were asked an identical set of questions on each survey about their knowledge, skills, and abilities (KSA) regarding COVID-19. Composite scores were created for each KSA learning domain. Responses were provided using a five-point Likert scale ranging from 1 = strongly disagree to 5 = strongly agree. RESULTS: Out of the 724 students enrolled, 645 students completed both the pre- and post-course assessment surveys. Findings show that there were both meaningful and statistically significant differences in students' responses to the pre- and post-course surveys. Results show 1.) a significant mean increase in the knowledge composite score of 1.01, 95% CI [0.95, 1.06], t(644) = 36.4, p < .001, d = 1.43; 2.) a significant mean increase in the skills composite score of .55, 95% CI [0.50, 0.60], t(644) = 20.70, p < .001, d = 0.81. and 3.) a significant mean increase of the abilities composite score of 1.02, 95% CI [.97, 1.07], t(644) = 36.56, p < .001, d = 1.44. CONCLUSIONS: These findings demonstrate that the student-developed, online Fundamentals of COVID-19 course resulted in notable and statistically significant educational effects. The increase in students' self-reported ratings, especially in the knowledge and abilities domains, indicate that meaningful learning occurred within the course. These findings have notable implications for medical student training during healthcare emergencies, such as a pandemic, as well as within modern clerkship environments. Overall, our findings provide evidence that student-led curricular design and virtual delivery of course content can be effective tools in undergraduate medical education.