Live virus vaccination following pediatric liver transplantation: Outcomes from two academic children's hospitals.

Pediatric liver transplant (LT) recipients are often transplanted at a young age, precluding them from receiving live virus vaccinations (LVV) such as varicella (VZV) vaccine and measles, mumps and rubella. This places them at profound risk for vaccine preventable illness. We sought to detail safety of vaccination. This was a retrospective cohort study of pediatric LT recipients at two children's hospitals. Among 204 LT recipients included in the study, 97 received at least one LVV after LT. Six patients who did not receive LVV after transplant had evidence of vaccine-preventable infection following vaccination (one disseminated VZV disease, five VZV-related rash), while one patient who received LVV after transplant developed a diffuse VZV-related rash. Rejection rates were the same between those that did and did not receive a live virus vaccine post-transplant. There were no serious adverse events caused by vaccination post-transplant. LVV following LT was safe at our two institutions, although there exist limitations in our study due to its retrospective study design. Larger scale studies should be performed to evaluate the effectiveness of LVV in relation to immunosuppression.

The Epidemiology of Severe Acute Respiratory Syndrome Coronavirus 2 in a Pediatric Healthcare Network in the United States.

BACKGROUND: Understanding the prevalence and clinical presentation of coronavirus disease 2019 in pediatric patients can help healthcare providers and systems prepare and respond to this emerging pandemic. METHODS: This was a retrospective case series of patients tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) across a pediatric healthcare network, including clinical features and outcomes of those with positive test results. RESULTS: Of 7256 unique children tested for SARS-CoV-2, 424 (5.8%) tested positive. Patients aged 18-21 years had the highest test positive rate (11.2%), while those aged 1-5 years had the lowest (3.9%). By race, 10.6% (226/2132) of black children tested positive vs 3.3% (117/3592) of white children. By indication for testing, 21.1% (371/1756) of patients with reported exposures or clinical symptoms tested positive vs 3.8% (53/1410) of those undergoing preprocedural or preadmission testing. Of 424 patients who tested positive for SARS-CoV-2, 182 (42.9%) had no comorbidities, 87 (20.5%) had asthma, and 55 (13.0%) were obese. Overall, 52.1% had cough, 51.2% fever, and 14.6% shortness of breath. Seventy-seven (18.2%) SARS-CoV-2-positive patients were hospitalized, of whom 24 (31.2%) required respiratory support. SARS-CoV-2-targeted antiviral therapy was given to 9 patients, and immunomodulatory therapy to 18 patients. Twelve (2.8%) SARS-CoV-2-positive patients required mechanical ventilation, and 2 patients required extracorporeal membrane oxygenation. Two patients died. CONCLUSIONS: In this large cohort of pediatric patients tested for SARS-CoV-2, the rate of infection was low but varied by testing indication. The majority of cases were mild and few children had critical illness.

Multipurpose care solution-induced corneal surface disruption and Pseudomonas aeruginosa internalization in the rabbit corneal epithelium.

PURPOSE: To evaluate the effects of a chemically preserved multipurpose contact lens care solution (MPS) on the corneal epithelial surface and Pseudomonas aeruginosa (PA) internalization in the rabbit corneal epithelium. METHODS: Rabbits were fit in one eye with a silicone hydrogel lens (balafilcon A) soaked overnight in a borate-buffered MPS (BioTrue). The contralateral eye was fit with a lens removed directly from the blister pack containing borate-buffered saline (control). Lenses were worn for 2 hours. Upon lens removal, corneas were challenged ex vivo with invasive PA strain 6487 and assessed for PA internalization. Ultrastructural changes were assessed using scanning electron (SEM) and transmission electron microscopy (TEM). RESULTS: Scanning electron microscopy showed frank loss of surface epithelium in MPS-exposed eyes, while control eyes exhibited occasional loss of surface membranes but retention of intact junctional borders. Transmission electron microscopy data supported and extended SEM findings, demonstrating the presence of epithelial edema in MPS-treated eyes. There was a 12-fold increase in PA uptake into the corneal epithelium following wear of the MPS-treated lens compared to control (P = 0.008). CONCLUSIONS: These data demonstrate that corneal exposure to MPS during lens wear damages the surface epithelium and are consistent with our previous clinical data showing an increase in bacterial binding to exfoliated epithelial cells following MPS use with resultant increased risk for lens-mediated infection. These findings also demonstrate that the PA invasion assay may provide a highly sensitive quantitative metric for assessing the physiological impact of lens-solution biocompatibility on the corneal epithelium.