Results of Two Cases of Pig-to-Human Kidney Xenotransplantation.

BACKGROUND: Xenografts from genetically modified pigs have become one of the most promising solutions to the dearth of human organs available for transplantation. The challenge in this model has been hyperacute rejection. To avoid this, pigs have been bred with a knockout of the alpha-1,3-galactosyltransferase gene and with subcapsular autologous thymic tissue. METHODS: We transplanted kidneys from these genetically modified pigs into two brain-dead human recipients whose circulatory and respiratory activity was maintained on ventilators for the duration of the study. We performed serial biopsies and monitored the urine output and kinetic estimated glomerular filtration rate (eGFR) to assess renal function and xenograft rejection. RESULTS: The xenograft in both recipients began to make urine within moments after reperfusion. Over the 54-hour study, the kinetic eGFR increased from 23 ml per minute per 1.73 m2 of body-surface area before transplantation to 62 ml per minute per 1.73 m2 after transplantation in Recipient 1 and from 55 to 109 ml per minute per 1.73 m2 in Recipient 2. In both recipients, the creatinine level, which had been at a steady state, decreased after implantation of the xenograft, from 1.97 to 0.82 mg per deciliter in Recipient 1 and from 1.10 to 0.57 mg per deciliter in Recipient 2. The transplanted kidneys remained pink and well-perfused, continuing to make urine throughout the study. Biopsies that were performed at 6, 24, 48, and 54 hours revealed no signs of hyperacute or antibody-mediated rejection. Hourly urine output with the xenograft was more than double the output with the native kidneys. CONCLUSIONS: Genetically modified kidney xenografts from pigs remained viable and functioning in brain-dead human recipients for 54 hours, without signs of hyperacute rejection. (Funded by Lung Biotechnology.).

The Child Opportunity Index and Disparities in Pediatric Asthma Hospitalizations Across One Ohio Metropolitan Area, 2011-2013.

OBJECTIVES: To determine whether the Child Opportunity Index (COI), a nationally available measure of relative educational, health/environmental, and social/economic opportunity across census tracts within metropolitan areas, is associated with population- and patient-level asthma morbidity. STUDY DESIGN: This population-based retrospective cohort study was conducted between 2011 and 2013 in a southwest Ohio county. Participants included all children aged 1-16 years with hospitalizations or emergency department visits for asthma or wheezing at a major pediatric hospital. Patients were identified using discharge diagnosis codes and geocoded to their home census tract. The primary population-level outcome was census tract asthma hospitalization rate. The primary patient-level outcome was rehospitalization within 12 months of the index hospitalization. Census tract opportunity was characterized using the COI and its educational, health/environmental, and social/economic domains. RESULTS: Across 222 in-county census tracts, there were 2539 geocoded hospitalizations. The median asthma-related hospitalization rate was 5.0 per 1000 children per year (IQR, 1.9-8.9). Median hospitalization rates in very low, low, moderate, high, and very high opportunity tracts were 9.1, 7.6, 4.6, 2.1, and 1.8 per 1000, respectively (P < .0001). The social/economic domain had the most variables significantly associated with the outcome at the population level. The adjusted patient-level analyses showed that the COI was not significantly associated with a patient's risk of rehospitalization within 12 months. CONCLUSIONS: The COI was associated with population-level asthma morbidity. The details provided by the COI may inform interventions aimed at increasing opportunity and reducing morbidity across regions.

Failure to Thrive, Metabolic Acidosis, and Diarrhea in a 7-Week-Old Infant.

A 7-week-old infant presented to the emergency department with fussiness, decreased oral intake, loose stool, and respiratory distress for 2 days. The patient was born full-term with an uncomplicated birth history but had a history of slow weight gain. He was alert, but toxic-appearing at presentation, hypothermic with signs of dehydration, and with respiratory failure. He was found to have severe anion gap metabolic acidosis, hypokalemia, elevated lactate, and hyperammonemia. He responded well to initial resuscitation and was admitted to the ICU for intravenous electrolyte replacement, bowel rest, and respiratory support. A workup was pursued for failure to thrive with severe malnutrition, hyperammonemia, hyperlactatemia, anemia, vitamin D deficiency, and electrolyte abnormalities. After stabilization, he was restarted on enteral feeds and had a recurrence of loose stool and severe electrolyte abnormalities, which were refractory to enteral supplementations and required readmission to the ICU. His hospital course extended several weeks, included several subspecialty consultations, and ended with a surprising diagnosis of exclusion based on his clinical response to therapy.

Pig-to-human heart xenotransplantation in two recently deceased human recipients.

Genetically modified xenografts are one of the most promising solutions to the discrepancy between the numbers of available human organs for transplantation and potential recipients. To date, a porcine heart has been implanted into only one human recipient. Here, using 10-gene-edited pigs, we transplanted porcine hearts into two brain-dead human recipients and monitored xenograft function, hemodynamics and systemic responses over the course of 66 hours. Although both xenografts demonstrated excellent cardiac function immediately after transplantation and continued to function for the duration of the study, cardiac function declined postoperatively in one case, attributed to a size mismatch between the donor pig and the recipient. For both hearts, we confirmed transgene expression and found no evidence of cellular or antibody-mediated rejection, as assessed using histology, flow cytometry and a cytotoxic crossmatch assay. Moreover, we found no evidence of zoonotic transmission from the donor pigs to the human recipients. While substantial additional work will be needed to advance this technology to human trials, these results indicate that pig-to-human heart xenotransplantation can be performed successfully without hyperacute rejection or zoonosis.

Association of Social Determinants of Health With Rapid Response Events: A Retrospective Cohort Trial in a Large Pediatric Academic Hospital System.

Background: Social determinants of health (SDH) are known to impact hospital and intensive care unit (ICU) outcomes. Little is known about the association between SDH and pediatric rapid response (RR) events and understanding this impact will help guide future interventions aimed to eliminate health disparities in the inpatient setting. Objectives: The primary objective of this study is to describe the association between SDH and RR utilization (number of RR events, time to RR event, shift of event and caller). The secondary objective is to determine if SDH can predict hospital length of stay (LOS), ICU transfer, critical deterioration (CD), and mortality. Methods: A retrospective cohort study was conducted. We reviewed all RR events from 2016 to 2019 at a large, academic, pediatric hospital system including a level 1 trauma center and two satellite community campuses. All hospitalized patients up to age 25 who had a RR event during their index hospitalization were included. Exposure variables included age, gender, race/ethnicity, language, income, insurance status, chronic disease status, and repeat RR event. The primary outcome variables were hospital LOS, ICU transfer, CD, and mortality. The odds of mortality, CD events and ICU transfer were assessed using unadjusted and multivariable logistic regression. Associations with hospital LOS were assessed with unadjusted and multivariable quantile regression. Results: Four thousand five hundred and sixty-eight RR events occurred from 3,690 unique admissions and 3301 unique patients, and the cohort was reduced to the index admission. The cohort was largely representative of the population served by the hospital system and varied according to race and ethnicity. There was no variation by race/ethnicity in the number of RR events or the shift in which RR events occurred. Attending physicians initiated RR calls more for event for non-Hispanic patients of mixed or other race (31.6% of events), and fellows and residents were more likely to be the callers for Hispanic patients (29.7% of events, p = 0.002). Families who are non-English speaking are also less likely to activate the RR system (12% of total RR events, p = 0.048). LOS was longest for patients speaking languages other than Spanish or English and CD was more common in patients with government insurance. In adjusted logistic regression, Hispanic patients had 2.5 times the odds of mortality (95% CI: 1.43-4.53, p = 0.002) compared with non-Hispanic white patients. Conclusion: Disparities exist in access to and within the inpatient management of pediatric patients. Our results suggest that interventions to address disparities should focus on Hispanic patients and non-English speaking patients to improve inpatient health equity. More research is needed to understand and address the mortality outcomes in Hispanic children compared to other groups.

Successful A2 to B Deceased Donor Kidney Transplant after Desensitization for High-Strength Non-HLA Antibody Made Possible by Utilizing a Hepatitis C Positive Donor.

Desensitization using plasma exchange can remove harmful antibodies prior to transplantation and mitigate risks for hyperacute and severe early acute antibody-mediated rejection. Traditionally, the use of plasma exchange requires a living donor so that the timing of treatments relative to transplant can be planned. Non-HLA antibody is increasingly recognized as capable of causing antibody-mediated renal allograft rejection and has been associated with decreased graft longevity. Our patient had high-strength non-HLA antibody deemed prohibitive to transplantation without desensitization, but no living donors. As the patient was eligible to receive an A2 ABO blood group organ and was willing to accept a hepatitis C positive donor kidney, this afforded a high probability of receiving an offer within a short enough time frame to attempt empiric desensitization in anticipation of a deceased donor transplant. Fifteen plasma exchange treatments were performed before the patient received an organ offer, and the patient was successfully transplanted. Hepatitis C infection was treated posttransplant. No episodes of rejection were observed. At one-year posttransplant, the patient maintains good graft function. In this case, willingness to consider nontraditional donor organs enabled us to mimic living donor desensitization using a deceased donor.

The Impact of Infant Well-Child Care Compliance and Social Risks on Emergency Department Utilization.

Deployment of medical and social services at well-child visits promotes child health. A retrospective review of the electronic health record was conducted for infants presenting for their "newborn" visit over a 2-year period at an urban, academic primary care center. Primary outcomes were time to first emergency department (ED) visit, number of ED visits (emergent or nonemergent), and number of nonemergent ED visits by 2 years of life. Records from 212 consecutive newborns were evaluated-59.9% were black/African American and 84.4% publicly insured. A total of 72.6% visited the ED by 2 years of life. Sixty percent received ≥5 well-child visits by 14 months; 25.9% reported ≥1 social risk. There were no statistically significant associations between number of completed well-child visits, or reported social risks, and ED utilization. Renewed focus on preventive care delivery and content and its effect on ED utilization, and other patient outcomes, is warranted.