not-yet-known not-yet-known not-yet-known unknown Background: Pediatric immunocompromised patients are at an increased risk of severe respiratory syncytial virus (RSV) infection. Here, we aimed to describe the clinical course and outcomes of RSV infection in immunocompromised children. Methods: This single-center study was conducted at St. Jude Children’s Research Hospital in immunocompromised children ≤21 years old, who had a positive RSV clinical test in the clinic or hospital from 2007 to 2019. Demographic and clinical characteristics, laboratory values, delays in the treatment of patients’ underlying conditions, and outcomes were extracted from the patients’ electronic medical records. Multivariate models were constructed to identify risk factors predictive of severe RSV LRTI. Results: In total, 391 patients were included. Most children (86%) were > 2 years of age, with a median age of 5 years. Acute lymphoblastic leukemia (ALL) was the most common underlying disease. Most patients presented with upper respiratory tract infections (n = 335; 85.7%). Approximately 6% of patients progressed to lower respiratory tract infections. More than half (58.8%) of the patients were hospitalized, and therapy for the underlying disease was modified or delayed due to RSV infection in one-third of the patients. Severe RSV infections were observed in 62 patients (15.9%). All-cause mortality was reported in 10 patients (2.6%), with three RSV-related deaths (0.7%). Conclusions: A high proportion of immunocompromised children with RSV infection require hospitalization. Hospitalization was observed in those aged >2 years, and an overall treatment delay for the underlying disease occurred in one-third of the patients. The burden associated with RSV in immunocompromised children is high irrespective of age and has direct and indirect consequences on their cancer treatment plans.

Novel human astrovirus (HAstV) strains have been recently shown to cause fatal encephalitis in immunocompromised patients. We report two cases from our institution. A 2-year old female undergoing treatment for acute lymphoblastic leukemia and a 9-year old male with refractory acute myeloid leukemia. Both were found to have HAstV-VA1 in the cerebrospinal fluid (CSF) by metagenomics next generation sequencing (m-NGS) after the initial evaluation did not reveal any etiology. Patient 1 remains alive, in remission, showing gradual neurological improvement after treatment with steroids, intravenous immunoglobulin, ribavirin, nitazoxanide and Peg-INF-alpha 2b. Patient 2 died 7 weeks later while receiving palliative care.

Objective: To assess the utility of a test-based approach to shorten isolation of healthcare workers with COVID-19 in the setting of the highly transmissible omicron variant Methods: Between December 24th, 2021, to January 5th, 2022 HCWs who tested positive for SARS-CoV-2 were re-tested at least five days since onset of symptoms. Results: 46 sequential fully COVID-19 vaccinated HCWs who had tested positive for SARS-CoV-2 underwent follow up testing. All the isolates were confirmed as omicron variants and only 4 (8.7%) were negative 5 days or more since onset of symptoms., Conclusions: Implementation of a test-based strategy is logistically challenging, increases costs and did not lead to shorter isolation in our institution.

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked enzyme disorder associated with hemolytic anemia after exposure to certain medications or foods. Activity testing is the gold standard for detecting G6PD deficiency; however, this test is affected by various hematologic parameters. Clinical G6PD genotyping is included in pharmacogenetic arrays and clinical sequencing and may be reconciled with activity results. Methods: Patients (n=1,391) enrolled on an institutional pharmacogenetic testing protocol underwent clinical G6PD genotyping for 164 G6PD variants. For the 446 patients with G6PD activity results, algorithms were designed to assign G6PD status, accounting for known interferences with the activity assay and for G6PD genotype results. We developed clinical decision support alerts to inform prescribers when high-risk medications were prescribed, warning of gene-drug interactions and recommending therapy alteration. Results: Of 1,391 patients with genotype, 1,334 (95.9%) patients were predicted to have normal G6PD activity, 30 (2.1%) were predicted to have variable G6PD activity, and 27 (2%) were predicted to have deficient G6PD activity. Of the 417 patients with a normal genotype and an activity result, 415 (99.5%) had a concordant normal G6PD phenotype. Of the 21 patients with a deficient genotype and an activity result, 18 (85.7%) had a concordant deficient activity result. Genotyping reassigned phenotype in 5 patients with discordant genotype and activity results: 3 switched from normal to deficient, and 2 switched from deficient to normal. Conclusion: G6PD activity and genotyping are two independent testing methods which can be used in conjunction to assign a more informed G6PD phenotype.