Impact of Early Rejection Treatment on Infection Development in Kidney Transplant Recipients: A Propensity Analysis.

Introduction: The impact of renal allograft rejection treatment on infection development has not been formally defined in the literature. Methods: We conducted a retrospective cohort study of 185 rejection (case) and 185 nonrejection (control) kidney transplant patients treated at our institution from 2014 to 2020 to understand the impact of rejection on infection development. Propensity scoring was used to match cohorts. We collected data for infections within 6 months of rejection for the cases and 18 months posttransplant for controls. Results: In 370 patients, we identified 466 infections, 297 in the controls, and 169 in the cases. Urinary tract infections (38.9%) and cytomegalovirus viremia (13.7%) were most common. Cumulative incidence of infection between the case and controls was 2.17 (CI 1.54-3.05); p < 0.001. There was no difference in overall survival (HR 0.90, CI 0.49-1.66) or graft survival (HR 1.27, CI 0.74-2.20) between the groups. There was a significant difference in overall survival (HR 2.28, CI 1.14-4.55; p = 0.019) and graft survival (HR 1.98, CI 1.10-3.56; p = 0.023) when patients with infection were compared to those without. Conclusions: As previously understood, rejection treatment is a risk factor for subsequent infection development. Our data have defined this relationship more clearly. This study is unique, however, in that we found that infections, but not rejection, negatively impacted both overall patient survival and allograft survival, likely due to our institution's robust post-rejection protocols. Clinicians should monitor patients closely for infections in the post-rejection period and have a low threshold to treat these infections while also restarting appropriate prophylaxis.

Meteorological and environmental factors that impact pollen counts, allergenicity, and thresholds: A scoping review.

Background: Pollen is a key source of aeroallergens responsible for allergic rhinitis, conjunctivitis, and asthma. Objective: The goal of this scoping review was to summarize current available literature on the factors that affect pollen counts, allergenicity, and thresholds that induce symptoms in individuals who were sensitized. Methods: Several databases showed no published articles with a similar scope as of January 2022. A search of these data bases yielded 373 articles for assessment. These were then reviewed for relevance, and articles were selected to demonstrate the breadth of available data on pollen counts, allergenicity, and thresholds that induce symptoms in individuals who were sensitized. Additional articles were identified through examination of bibliographies of search-identified articles. Results: Several environmental factors have shown a correlation with pollen counts and allergen load, including the distance from the source, wind characteristics, pollen size, terrain, urban environments, air composition (particulate matter, CO2 levels, ozone, NO2), and weather conditions (humidity, thunderstorms, precipitation). Pollen thresholds at which symptoms were induced varied by study, pollen type, symptom, disease, and location. In addition, there was heterogeneity in study designs, threshold definition, and outcome measures. Conclusion: This scoping review demonstrates the plethora of variables that influence the relationship between pollen and the symptoms of allergic diseases. Analysis of the available data sheds light on the complex interaction between environmental and biologic factors that affect pollen's role in allergic diseases and provides guidance on multiple areas for further investigation.

Infections following rejection therapies in kidney and liver transplant recipients.

INTRODUCTION: Infections are known complications of solid-organ transplant. Treatment for rejection may increase risk of infection. We aimed to study frequency of infection and identify the risk factors for infections in solid organ transplant (SOT) (liver and kidney) recipients treated for rejection. METHODS: This is a retrospective chart review of all liver and kidney transplant recipients treated for rejection at our institution from 2014 to 2020. We collected information on episodes of acute rejection in the first year of transplant and infections within 6 months following rejection treatment. RESULTS: We identified 257 transplant patients treated for rejection. One hundred twelve (43.6%) developed infections, with a total of 226 infections. Urinary tracts infections were the most common, 72 (31.9%), followed by cytomegalovirus viremia in 37 (16.4%), bacteremia in 24 (10.6%), and BK virus in 14 (6.2%). Female sex (p = .047), elevated neutrophil count at rejection (p = .002), and increased number of rejection episodes (p = .022) were predictors of infection in kidney and simultaneous liver-kidney recipients. No specific type of induction or rejection therapy was identified as a risk factor for infection, likely due to the prophylaxis protocols at our institution. Infection post rejection treatment was associated with higher graft loss (p = .021) and mortality (p = .031) in kidney transplant recipients. CONCLUSIONS: Infections are common complications after treatment of SOT rejection. Female gender, higher neutrophil at time of rejection, and increased numbers of rejection episodes were predictors of infections after rejection in simultaneous liver-kidney and kidney transplant patients. Infections were predictors of graft loss at 6 months and mortality at any point in follow-up in kidney transplant patients.