Fluid Resuscitation and Progression to Renal Replacement Therapy in Patients With COVID-19.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is associated with respiratory symptoms and renal effects. Data regarding fluid resuscitation and kidney injury in COVID-19 are lacking, and understanding this relationship is critical. OBJECTIVES: To determine if there is an association between fluid volume administered in 24 h and development of renal failure in COVID-19 patients. METHODS: Retrospective chart review; 14 hospitals in Indiana. Included patients were adults admitted between March 11, 2020 and April 13, 2020 with a positive test for severe acute respiratory syndrome coronavirus 2 within 3 days of admission. Patients requiring renal replacement therapy prior to admission were excluded. Volumes and types of resuscitative intravenous fluids in the first 24 h were obtained with demographics, medical history, and other objective data. The primary outcome was initiation of renal replacement therapy. Logistic regression modeling was utilized in creating multivariate models for determining factors associated with the primary outcome. RESULTS: The fluid volume received in the first 24 h after hospital admission was associated with initiation of renal replacement therapy in two different multivariate logistic regression models. An odds ratio of 1.42 (95% confidence interval 1.01-1.99) was observed when adjusting for age, heart failure, obesity, creatinine, bicarbonate, and total fluid volume. An odds ratio of 1.45 (95% confidence interval 1.02-2.05) was observed when variables significant in univariate analysis were adjusted for. CONCLUSIONS: Each liter of intravenous fluid administered to patients with COVID-19 in the first 24 h of presentation was independently associated with an increased risk for initiation of renal replacement therapy, supporting judicious fluid administration in patients with this disease.

Characteristics of COVID-19 patients with bacterial coinfection admitted to the hospital from the emergency department in a large regional healthcare system.

INTRODUCTION: The rate of bacterial coinfection with SARS-CoV-2 is poorly defined. The decision to administer antibiotics early in the course of SARS-CoV-2 infection depends on the likelihood of bacterial coinfection. METHODS: We performed a retrospective chart review of all patients admitted through the emergency department with confirmed SARS-CoV-2 infection over a 6-week period in a large healthcare system in the United States. Blood and respiratory culture results were abstracted and adjudicated by multiple authors. The primary outcome was the rate of bacteremia. We secondarily looked to define clinical or laboratory features associated with bacteremia. RESULTS: There were 542 patients admitted with confirmed SARS-CoV-2 infection, with an average age of 62.8 years. Of these, 395 had blood cultures performed upon admission, with six true positive results (1.1% of the total population). An additional 14 patients had positive respiratory cultures treated as true pathogens in the first 72 h. Low blood pressure and elevated white blood cell count, neutrophil count, blood urea nitrogen, and lactate were statistically significantly associated with bacteremia. Clinical outcomes were not statistically significantly different between patients with and without bacteremia. CONCLUSIONS: We found a low rate of bacteremia in patients admitted with confirmed SARS-CoV-2 infection. In hemodynamically stable patients, routine antibiotics may not be warranted in this population.

Risk factors associated with hospital admission in COVID-19 patients initially admitted to an observation unit.

BACKGROUND: No set guidelines to guide disposition decisions from the emergency department (ED) in patients with COVID-19 exist. Our goal was to determine characteristics that identify patients at high risk for adverse outcomes who may need admission to the hospital instead of an observation unit. METHODS: We retrospectively enrolled 116 adult patients with COVID-19 admitted to an ED observation unit. We included patients with bilateral infiltrates on chest imaging, COVID-19 testing performed, and/or COVID-19 suspected as the primary diagnosis. The primary outcome was hospital admission. We assessed risk factors associated with this outcome using univariate and multivariable logistic regression. RESULTS: Of 116 patients, 33 or 28% (95% confidence interval [CI] 20-37%) required admission from the observation unit. On multivariable logistic regression analysis, we found that hypoxia defined as room-air oxygen saturation < 95% (OR 3.11, CI 1.23-7.88) and bilateral infiltrates on chest radiography (OR 5.57, CI 1.66-18.96) were independently associated with hospital admission, after adjusting for age. Two three-factor composite predictor models, age > 48 years, bilateral infiltrates, hypoxia, and Hispanic race, bilateral infiltrates, hypoxia yield an OR for admission of 4.99 (CI 1.50-16.65) with an AUC of 0.59 (CI 0.51-0.67) and 6.78 (CI 2.11-21.85) with an AUC of 0.62 (CI 0.54-0.71), respectively. CONCLUSIONS: Over 1/4 of suspected COVID-19 patients admitted to an ED observation unit ultimately required admission to the hospital. Risk factors associated with admission include hypoxia, bilateral infiltrates on chest radiography, or the combination of these two factors plus either age > 48 years or Hispanic race.

First-time Diabetic Ketoacidosis in Type 2 Diabetics With Covid-19 Infection: A Novel Case Series.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 is a novel coronavirus first diagnosed in U.S. hospitals in January 2020. Typical presenting symptoms include fever, dry cough, dyspnea, and hypoxia. However, several other symptoms have been reported, including fatigue, weakness, diarrhea, and abdominal pain. We have identified a series of patients with diabetic ketoacidosis (DKA) likely precipitated by coronavirus disease 2019 (COVID-19). CASE SERIES: We describe 5 patients with previously known type 2 diabetes and no history of DKA, who presented to the emergency department with new-onset DKA and COVID-19. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Diabetes mellitus is a known risk factor for poor outcomes in viral respiratory illnesses, including COVID-19. Infection may precipitate DKA in patients with type 2 diabetes. Aggressive management of these patients is recommended; however, management guidelines have not yet been put forth for this unique subset of patients.

A Novel Technique for Ice Water Immersion in Severe Drug-Induced Hyperthermia in the Emergency Department.

BACKGROUND: Methamphetamine can cause life-threatening hyperthermia and treatment must be aggressive and rapid. There are multiple methods of cooling, with cold-water immersion being one of the most effective treatment options. However, this method is technically difficult to institute in the emergency department setting. CASE REPORT: We report 2 patients who presented with life-threatening hyperthermia from methamphetamine and were treated in the emergency department with a novel technique of using a body bag filled with ice water to perform rapid cooling. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This method of cooling is a safe, rapid, and efficacious method for emergency physicians to perform cold water immersion in the department.

A Combined Intervention of Zinc, Multiple Micronutrients, and Albendazole Does Not Ameliorate Environmental Enteric Dysfunction or Stunting in Rural Malawian Children in a Double-Blind Randomized Controlled Trial.

BACKGROUND: Environmental enteric dysfunction (EED) and linear growth stunting affect many rural agrarian children in the developing world and contribute to the persistently high rates of stunting that are observed worldwide. Effective interventions to consistently ameliorate EED are lacking. OBJECTIVE: We tested whether a bundle of safe and affordable interventions would decrease EED and stunting over 12-24 wk in a cohort of rural Malawian children 12-35 mo old. METHODS: This was a randomized, double-blind, placebo-controlled clinical trial in which the intervention group received a single dose of albendazole and 14 d of zinc at enrollment and after 20 wk. The intervention group also received a daily multiple micronutrient powder throughout the 24 wk of study. The primary outcomes were improvements in EED, as measured by the urinary lactulose-to-mannitol ratio (L:M ratio) from dual-sugar absorption testing, and linear growth. Urinary L:M ratios and anthropometric measurements were evaluated after 12 and 24 wk of intervention and compared with a placebo group that did not receive any of these interventions. RESULTS: A total of 254 children were enrolled at a mean age of 24 mo; 55% were female. Their mean weight-for-age z score was -1.5, and their mean length-for-age z score was -0.9. After 12 and 24 wk of study, increases in the L:M ratio did not differ between the intervention group (0.071 and 0.088 units, respectively) and the placebo group (0.073 and 0.080 units, respectively) (P = 0.87 and 0.19, respectively). Relative changes in length and weight also did not differ significantly between groups at any time point. CONCLUSION: The combined usage of albendazole, zinc, and a daily multiple micronutrient powder did not decrease EED or stunting in this population of agrarian children 12-35 mo old in rural Malawi. Alternative interventions to improve these diseases should be investigated. This trial was registered at clinicaltrials.gov as NCT02253095.

Efficacy of Benzodiazepines or Antihistamines for Patients With Acute Vertigo: A Systematic Review and Meta-analysis.

Importance: Acute vertigo can be disabling. Antihistamines and benzodiazepines are frequently prescribed as "vestibular suppressants," but their efficacy is unclear. Objective: To assess the efficacy of antihistamines and benzodiazepines in the treatment of acute vertigo from any underlying cause. Data Sources: We searched the PubMed, CENTRAL, EMBASE, CINAHL, Scopus, and ClinicalTrials.gov databases from inception to January 14, 2019, without language restrictions. Bibliographies of the included studies and relevant reviews were also screened. Study Selection: We included randomized clinical trials (RCTs) comparing antihistamine or benzodiazepine use with another comparator, placebo, or no intervention for patients with a duration of acute vertigo for 2 weeks or less. Studies of healthy volunteers, prophylactic treatment, or induced vertigo were excluded, as were studies that compared 2 medications from the same class. Data Extraction and Synthesis: Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, data were extracted and risk of bias was assessed by 2 authors independently for each study. Data were pooled using a random-effects model. Main Outcomes and Measures: The predefined primary outcome was change in 10- or 100-point vertigo or dizziness visual analog scale (VAS) scores at 2 hours after treatment. Secondary outcomes included change in nausea VAS scores at 2 hours, use of rescue medication at 2 hours, and improvement or resolution of vertigo at 1 week or 1 month. Results: Of the 27 trials identified in the systematic review, 17 contributed to the quantitative meta-analysis and involved a total of 1586 participants. Seven trials with a total of 802 participants evaluated the primary outcome of interest: single-dose antihistamines resulted in significantly more improvement on 100-point VAS scores compared with benzodiazepines (difference, 16.1 [95% CI, 7.2 to 25.0]) but not compared with other active comparators (difference, 2.7 [95% CI, -6.1 to 11.5]). At 1 week and 1 month, neither daily benzodiazepines nor antihistamines were reported to be superior to placebo. RCTs comparing the immediate effects of medications (at 2 hours) after a single dose generally had a low risk of bias, but those evaluating 1-week and 1-month outcomes had a high risk of bias. Conclusions and Relevance: Moderately strong evidence suggests that single-dose antihistamines provide greater vertigo relief at 2 hours than single-dose benzodiazepines. Furthermore, the available evidence did not support an association of benzodiazepine use with improvement in any outcomes for acute vertigo. Other evidence suggested that daily antihistamine use may not benefit patients with acute vertigo. Larger randomized trials comparing both antihistamines and benzodiazepines with placebo could better clarify the relative efficacy of these medications.

Immediate complications and pain relief associated with 296 fluoroscopically guided thoracic foraminal nerve blocks.

OBJECTIVE: The goal of this work is to review the thoracic foraminal nerve blocks and foraminal epidurals performed at a single institution to determine the incidence and types of immediate complications and pain relief associated with thoracic foraminal nerve blocks. MATERIALS AND METHODS: This retrospective study entailed a comprehensive review of the radiographs and reports of 296 injections performed in 225 examinations on 153 patients (60 men and 93 women). The overall mean age was 51.93 years (mean age for men, 50.71 years [range, 22-85 years]; mean age for women, 53.09 years [range, 18-84 years]). The data were later analyzed with contingency tables and chi-square tests. RESULTS: The overall complication rate was 4.1% (12/296). Complication rates at the different needle tip positions measured on frontal and lateral fluoroscopic views did not approach statistical significance (p = 0.15). Complications were higher with cephalocaudal flow outside local flow (p = 0.02). No serious complications occurred except for one pneumothorax, which could have been avoided. Immediate partial or complete pain relief was obtained in 88.5% (262/296) of the injections and 88.4% (199/225) of the examinations. CONCLUSION: Fluoroscopically guided thoracic foraminal nerve blocks are safe procedures and provide immediate partial or complete pain relief in a high percentage of patients.

Can we predict which COVID-19 patients will need transfer to intensive care within 24 hours of floor admission?

BACKGROUND: Patients with COVID-19 can present to the emergency department (ED) at any point during the spectrum of illness, making it difficult to predict what level of care the patient will ultimately require. Admission to a ward bed, which is subsequently upgraded within hours to an intensive care unit (ICU) bed, represents an inability to appropriately predict the patient's course of illness. Predicting which patients will require ICU care within 24 hours would allow admissions to be managed more appropriately. METHODS: This was a retrospective study of adults admitted to a large health care system, including 14 hospitals across the state of Indiana. Included patients were aged ≥ 18 years, were admitted to the hospital from the ED, and had a positive polymerase chain reaction (PCR) test for COVID-19. Patients directly admitted to the ICU or in whom the PCR test was obtained > 3 days after hospital admission were excluded. Extracted data points included demographics, comorbidities, ED vital signs, laboratory values, chest imaging results, and level of care on admission. The primary outcome was a combination of either death or transfer to ICU within 24 hours of admission to the hospital. Data analysis was performed by logistic regression modeling to determine a multivariable model of variables that could predict the primary outcome. RESULTS: Of the 542 included patients, 46 (10%) required transfer to ICU within 24 hours of admission. The final composite model, adjusted for age and admission location, included history of heart failure and initial oxygen saturation of <93% plus either white blood cell count > 6.4 or glomerular filtration rate < 46. The odds ratio (OR) for decompensation within 24 hours was 5.17 (95% confidence interval [CI] = 2.17 to 12.31) when all criteria were present. For patients without the above criteria, the OR for ICU transfer was 0.20 (95% CI = 0.09 to 0.45). CONCLUSIONS: Although our model did not perform well enough to stand alone as a decision guide, it highlights certain clinical features that are associated with increased risk of decompensation.

Clinical prediction rule for SARS-CoV-2 infection from 116 U.S. emergency departments 2-22-2021.

OBJECTIVES: Accurate and reliable criteria to rapidly estimate the probability of infection with the novel coronavirus-2 that causes the severe acute respiratory syndrome (SARS-CoV-2) and associated disease (COVID-19) remain an urgent unmet need, especially in emergency care. The objective was to derive and validate a clinical prediction score for SARS-CoV-2 infection that uses simple criteria widely available at the point of care. METHODS: Data came from the registry data from the national REgistry of suspected COVID-19 in EmeRgency care (RECOVER network) comprising 116 hospitals from 25 states in the US. Clinical variables and 30-day outcomes were abstracted from medical records of 19,850 emergency department (ED) patients tested for SARS-CoV-2. The criterion standard for diagnosis of SARS-CoV-2 required a positive molecular test from a swabbed sample or positive antibody testing within 30 days. The prediction score was derived from a 50% random sample (n = 9,925) using unadjusted analysis of 107 candidate variables as a screening step, followed by stepwise forward logistic regression on 72 variables. RESULTS: Multivariable regression yielded a 13-variable score, which was simplified to a 13-point score: +1 point each for age>50 years, measured temperature>37.5°C, oxygen saturation<95%, Black race, Hispanic or Latino ethnicity, household contact with known or suspected COVID-19, patient reported history of dry cough, anosmia/dysgeusia, myalgias or fever; and -1 point each for White race, no direct contact with infected person, or smoking. In the validation sample (n = 9,975), the probability from logistic regression score produced an area under the receiver operating characteristic curve of 0.80 (95% CI: 0.79-0.81), and this level of accuracy was retained across patients enrolled from the early spring to summer of 2020. In the simplified score, a score of zero produced a sensitivity of 95.6% (94.8-96.3%), specificity of 20.0% (19.0-21.0%), negative likelihood ratio of 0.22 (0.19-0.26). Increasing points on the simplified score predicted higher probability of infection (e.g., >75% probability with +5 or more points). CONCLUSION: Criteria that are available at the point of care can accurately predict the probability of SARS-CoV-2 infection. These criteria could assist with decisions about isolation and testing at high throughput checkpoints.

Establishing a Low-Resource Simulation Emergency Medicine Curriculum in Nepal.

Introduction: High-fidelity medical simulation is widely used in emergency medicine training because it mirrors the fast-paced environment of the emergency department (ED). However, simulation is not common in emergency medicine training programs in lower-resourced countries as cost, availability of resources, and faculty experience are potential limitations. We initiated a simulation curriculum in a low-resource environment. Methods: We created a simulation lab for medical officers and students on their emergency medicine rotation at a teaching hospital in Patan, Nepal, with 48,000 ED patient visits per year. We set up a simulation lab consisting of a room with one manikin, an intubation trainer, and a projector displaying a simulation cardiac monitor. In this environment, we ran a total of eight cases over 4 simulation days. Debriefing was done at the end of each case. At the end of the curriculum, an electronic survey was delivered to the medical officers to seek improvement for future cases. Results: All eight cases were well received, and learners appreciated the safe learning space and teamwork. Of note, the first simulation case that was run (the airway lab) was more difficult for learners due to lack of experience. Survey feedback included improving the debriefing content and adding further procedural skills training. Discussion: Simulation is a valuable experience for learners in any environment. Although resources may be limited abroad, a sustainable simulation lab can be constructed and potentially play a supportive role in developing an emergency medicine curriculum.

Troponin Testing and Coronary Syndrome in Geriatric Patients With Nonspecific Complaints: Are We Overtesting?

BACKGROUND: Elderly patients presenting to the emergency department (ED) with nonspecific complaints (NSCs) often undergo troponin testing to assess for atypical acute coronary syndrome (ACS). However, the rate of ACS and utility of troponin testing in this population is unknown. We sought to determine the rate of ACS and diagnostic yield of troponin testing in elderly patients with NSCs. METHODS: We retrospectively identified all patients aged ≥ 65 years triaged in the ED with NSCs from January 1, 2017, to June 30, 2017. NSCs were defined a priori and included complaints such as weakness, dizziness, or fatigue. NSCs were verified in ED provider notes by trained abstractors blind to testing results. Exclusions were focal chief complaint in provider notes, fever, and no troponin ordered. ACS was strictly defined and independently adjudicated by two trained physician researchers blind to the study hypothesis. We calculated the proportion of patients with ACS within 30 days and the test characteristics of troponin to diagnose ACS. RESULTS: Screening identified 1,146 encounters, and 552 were excluded for fever or focal chief complaints in the provider notes. Of the remaining 594 patients, troponin was ordered in 412 (69%), comprising the study cohort. The mean (±SD) age was 78.7 (±8.3) years, with 58% female and 75% admitted. Troponin elevation occurred in 81 patients (20%). ACS occurred in 5 of 412 (1.2%). Troponin was 100% sensitive (95% confidence interval [CI] = 48% to 100%) and 81% specific (95% CI = 77% to 85%) for ACS. Of patients with elevated troponin, 93.8% were false positives (no ACS). All patients with troponin elevation were admitted, but only one underwent angiography and no patients received reperfusion therapy. CONCLUSIONS: While consideration for ACS is prudent in selected elderly patients with NSCs, ACS was rare and no patients received reperfusion therapy. Given the false-positive rate in our study, our results may not support routine troponin testing for ACS in this population.

MetaCyc: a multiorganism database of metabolic pathways and enzymes.

The MetaCyc database (see URL http://MetaCyc.org) is a collection of metabolic pathways and enzymes from a wide variety of organisms, primarily microorganisms and plants. The goal of MetaCyc is to contain a representative sample of each experimentally elucidated pathway, and thereby to catalog the universe of metabolism. MetaCyc also describes reactions, chemical compounds and genes. Many of the pathways and enzymes in MetaCyc contain extensive information, including comments and literature citations. SRI's Pathway Tools software supports querying, visualization and curation of MetaCyc. With its wide breadth and depth of metabolic information, MetaCyc is a valuable resource for a variety of applications. MetaCyc is the reference database of pathways and enzymes that is used in conjunction with SRI's metabolic pathway prediction program to create Pathway/Genome Databases that can be augmented with curation from the scientific literature and published on the world wide web. MetaCyc also serves as a readily accessible comprehensive resource on microbial and plant pathways for genome analysis, basic research, education, metabolic engineering and systems biology. In the past 2 years the data content and the Pathway Tools software used to query, visualize and edit MetaCyc have been expanded significantly. These enhancements are described in this paper.

Common beans and cowpeas as complementary foods to reduce environmental enteric dysfunction and stunting in Malawian children: study protocol for two randomized controlled trials.

BACKGROUND: Interventions to decrease the burden of childhood malnutrition are urgently needed, as millions of children die annually owing to undernutrition and hundreds of millions more are left cognitively and physically stunted. Environmental enteric dysfunction (EED), a pervasive chronic subclinical inflammatory condition among children that develops when complementary foods are introduced, places them at high risk of stunting, malabsorption, and poor oral vaccine efficacy. Improved interventions to reduce the burden of EED and stunting are expected to markedly improve the nutritional status and survival of children throughout resource-limited settings. METHODS/DESIGN: We will conduct, in parallel, two prospective randomized controlled clinical trials to determine whether common beans or cowpeas improve growth, ameliorate EED, and alter the intestinal microbiome during a high-risk period in the lives of rural Malawian children. Study 1 will enroll children at 6 months of age and randomize them to receive common beans, cowpeas, or a standard complementary food for 6 months. Anthropometry will be compared among the three groups; EED will be assessed using a dual-sugar absorption test and by quantifying human intestinal mRNA for inflammatory messages; and the intestinal microbiota will be characterized by deep sequencing of fecal DNA, to enumerate host microbial populations and their metabolic capacity. Study 2 will enroll children 12-23 months old and follow them for 12 months, with similar interventions and assessments as Study 1. DISCUSSION: By amalgamating the power of rigorous clinical trials and advanced biological analysis, we aim to elucidate the potential of two grain legumes to reduce stunting and EED in a high-risk population. Legumes have potential as an affordable and effective complementary food intervention, given their cultural acceptability, nutritional content, and agricultural feasibility in sub-Saharan Africa. TRIAL REGISTRATION: Clinicaltrials.gov NCT02472262 and NCT02472301 .

Extending the short and long wavelength limits of bacteriochlorin near-infrared absorption via dioxo- and bisimide-functionalization.

Six new bacteriochlorins expanding the range of the strong near-infrared (NIR) absorption (Qy band) to both shorter and longer wavelengths (∼690 to ∼900 nm) have been synthesized and characterized. The architectures include bacteriochlorin-bisimides that have six-membered imide rings spanning the 3,5- and 13,15-macrocycle positions or five-membered imide rings spanning the ß-pyrrolic 2,3- and 12,13-positions. Both bisimide types absorb at significantly longer wavelength than the bacteriochlorin precursors (no fused rings), whereas oxo-groups at the 7- or 7,17-positions shift the Qy band to a new short wavelength limit. Surprisingly, bacteriochlorin-bisimides with five-membered ß-pyrrolic-centered imide rings have a Qy band closer to that of six-membered bacteriochlorin-monoimides. However, the five-membered bisimides (versus the six-membered bacteriochlorin-monoimides) have significantly enhanced absorption intensity that is paralleled by an ∼2-fold higher fluorescence yield (∼0.16 vs ∼0.07) and longer singlet excited-state lifetime (∼4 ns vs ∼2 ns). The photophysical enhancements derive in part from mixing of the lowest unoccupied frontier molecular orbitals of the five-membered imide ring with those of the bacteriochlorin framework. In general, all of the new bacteriochlorins have excited-state lifetimes (1-4 ns) that are sufficiently long for use in molecular-based systems for photochemical applications.

Comparison of adenoviral and adeno-associated viral vectors for pancreatic gene delivery in vivo.

Although effective gene therapy vectors have been developed for organ systems such as the liver, an effective delivery vector to the pancreas in vivo has remained elusive. Of the currently available viral vectors, adenovirus and adeno-associated virus (AAV) are two of the most efficient at transducing nondividing cells. We have constructed recombinant adenovirus (AdVLacZ), adeno-associated virus serotype 2 (AAV2LacZ), and pseudotyped adeno-associated virus serotype 5 and 8 (AAV5LacZ, AAV8LacZ) carrying the LacZ reporter, and compared the transduction efficiency of these four vectors in the pancreas of mice in vivo. We showed that adenovirus, AAV2, and AAV8 are capable of transducing the pancreas in vivo, but with different expression kinetics, efficiencies of transduction, and persistence. AdVLacZ-transduced pancreas exhibited maximum LacZ expression at 1 week postdelivery, with greater than 90% of expression lost at 4 weeks. AAV2LacZ-transduced pancreas displayed peak LacZ levels at 4 weeks postdelivery, with no significant decrease in expression for up to 8 weeks. AAV8LacZ was at least 10-fold more efficient than AAV2LacZ in transducing the pancreas in vivo, with significant levels of expression detectable at 1 week, whereas AAV5LacZ did not result in any detectable transgene expression at all tested time points. All three vectors primarily transduced pancreatic acinar cell types, with limited transduction of pancreatic endocrine cells. AdVLacZ elicited a significant leukocyte infiltration early after delivery into the pancreas, whereas none of the AAV vectors elicited a significant leukocyte response. None of the tested vectors caused significant changes in serum amylase or blood glucose levels, suggesting that they do not significantly alter pancreatic function. These vectors will be useful for studying novel gene delivery based treatments in animal models for diabetes and other pancreatic disorders.

Adenovirus transduction is required for the correction of diabetes using Pdx-1 or Neurogenin-3 in the liver.

The regeneration of insulin-producing cells in vivo has emerged as a promising method for treating type I diabetes. Pancreatic duodenal homeobox-1 (Pdx-1), NeuroD, and Neurogenin-3 (Ngn3) are pancreatic transcription factors important for the development of insulin-producing cells in the liver. Other groups have demonstrated that adenoviral-mediated transgene expression of these transcription factors in the liver can reverse hyperglycemia in diabetic mice. We delivered Pdx-1 and Ngn3 to the livers of diabetic mice using adeno-associated virus (AAV) serotype 8, a vector that has been shown to result in non-toxic, persistent, high level expression of the transgene. We were unable to correct hyperglycemia in mice with streptozotocin-induced diabetes using AAV vectors expressing Pdx-1 and Ngn3. However, when we co-delivered these transcription factor expression cassettes in non-viral vectors with an irrelevant adenoviral vector, we were able to correct hyperglycemia in diabetic animals. Further studies demonstrated that an antigen-dependent immune response elicited by the adenoviral capsid together with the expression of a pancreatic transcription factor was required for restoration of serum insulin levels by the liver. Our results suggest that a host response to adenovirus in combination with expression of a pro-endocrine pancreas transcription factor is sufficient to induce insulin production in the livers of diabetic mice.