Background In 2019, SARS‐CoV‐2 causing COVID‐19 emerged. Severe COVID‐19 symptoms may evolve by virtue of hyperactivation of the immune system. Equally, immunocompromised patients may be at increased risk to develop COVID‐19. However, treatment guidelines for children following liver transplantation are elusive. Methods As a liver transplantation center, we diagnosed and followed up 10 children (male/female: 8/2) with a median age of 8.5 years (IQR: 5.2–11.0), with COVID‐19 post‐liver transplant between March 2019 and December 2020. COVID‐19 diagnosis was based on PCR test and or florid X‐ray findings compatible with COVID‐19 in the absence of other cause. We retrospectively collected clinical and laboratory data from electronic patient records following written consent from patients/parents. Results Nine patients were diagnosed as definitive (PCR positive) with one patient being diagnosed as probable COVID‐19. Seven patients recovered without any support whereas three were admitted for non‐invasive oxygenation. Lymphopenia and/or high levels of serum IL‐6 were detected in four patients. Six patients mounted anti‐SARS‐CoV‐2 antibodies at median 30 days (IQR: 26.5–119.0) following COVID‐19 diagnosis. Antibiotic therapy, favipiravir, anakinra, and IVIG were used as treatment in 4,1,1 and 2 patients, respectively. Furthermore, we kept the tacrolimus with or without everolimus but stopped MMF in 2 patients. Importantly, liver allograft function was retained in all patients. Conclusions We found that being immunocompromised did not affect disease severity nor survival. Stopping MMF yet continuing with tacrolimus was an apt treatment modality in these patients.

Objectives: Liver biopsy is the standard in diagnosing liver diseases. Yet, it provides little space to perform comprehensive immune profiling of the liver. Hence, we explored whether fine needle aspirates (FNAs) could be used to elucidate the hepatic immunity in children. Methods: We enrolled 74 children undergoing diagnostic (n ¼ 17) or protocol biopsy (n ¼ 57) following liver transplantation (LT). Matched blood and FNAs were obtained. Additionally, explant liver tissue was collected from children (n ¼ 14) undergoing LT. Immune cells were isolated from peripheral blood, FNAs and explanted livers. Immunephenotypical profiling was done by flow cytometry. Results: Biopsied patients (58% female) were at a median age of 46 months (interquartile range [IQR]: 12-118) and LT patients (71% female) were 48 months (IQR: 21-134, P ¼ 0.78) old. CD69 þ , a hallmark of tissueresident immune cells was expressed in 1.3% of CD3 þ T cells from blood being higher in FNA (20%) and tissue (49%, P < 0.001). CD4 þ T-cell frequencies in tissue (13%) and FNAs (20%) were lower compared to blood (35%, P < 0.001) whereas CD8 þ T cells in tissue (33.5%) and FNA (32%) were higher than in blood (25%, P < 0.01). Mucosal associated invariant T cells were enriched in liver tissue (8.8%) and in the FNA (4.4%) compared to blood (1.7%, P < 0.001).Whereas the percentage of total Tregs (CD4 þ CD25 þ FOXP3 þ CD127 low/À ) decreased, the proportion of activated Tregs (CD4 þ CD45RA-FOXP3 high ) increased in FNA and explant. Breg (CD19 þ CD20 þ CD24 high CD38 high ) frequencies were similar in all groups. Conclusion: FNA is a practical method to sample the liver immune system collecting even small cell subsets such as regulatory T/B cells.

Background The delivery of healthcare services by telemedicine decreases costs of traveling for patients, is less time‐consuming, and most importantly permits the connection between highly skilled specialists and patients. However, whether the use of telemedicine (text messaging) for LT patients was affected by the COVID‐19 pandemic is unknown. Methods We collected data (following consent from patients and parents) from 57 patients (33 male/24 female) with a median age of 47 (IQR: 9–91) months, whom we followed up with text messaging between September 2019 and September 2020, spanning the 6 months prior to COVID‐19 and during this period. Results In total, 723 text message mediated consultations occurred during this period, henceforth simply referred to as “messages.” Three hundred and twenty‐eight (45%) messages occurred during the 6 months up to the start of the pandemic. Following the COVID‐19 outbreak, the number of messages increased to 395 (55%). The three most common reasons of messaging were post‐liver‐LT follow‐up messages ( n = 215/723, 29.7%), consultations for drug use ( n = 157/723, 21.7%), and medication prescriptions ( n = 113/723, 15.6%). Protocol biopsy discussions ( n = 33/723, 4.6%) and fever ( n = 27/723, 3.7%) were among others (vaccination, rash, diarrhea, cough, fatigue, acne). During the COVID‐19 outbreak, only post‐LT follow‐up messages increased significantly to 132/395 (33%) from 83/328 (25%) ( p ‐value: .02). Conclusions We found that the pandemic resulted in an increase in the total number of text message mediated consultations and specifically for the use of post‐LT follow‐up. Messaging was effective for post‐LT follow‐ups and all patients were at least satisfied.

VD plays an important role in health and many diseases notably by affecting the regulation of cell growth, inflammation, and the immune system. 1 VD stimulates innate immune cells such as macrophages to secrete anti-microbial peptides. 2 VD also controls adaptive immunity as the expression of >100 genes in T cells is altered by the interaction of VD and VD receptors in T cells. [3][4][5][6][7] For instance, VD increases IL-10 and FOXP3 expressing regulatory T cells, regulating both innate and adaptive immunity. 8 Observational studies have demonstrated that >50% of pediatric populations, that are healthy, had VD insufficiency, and only a minority was taking VD supplements. As low VD status is linked with several diseases, sustaining optimal VD levels by VD supplementation

Gastrointestinal bleeding is a rare but potentially life-threatening manifestation of eosinophilic gastrointestinal disorders (EGIDs). Here, we describe a case series comprising 5 pediatric patients between 7 and 12 years of age, who presented to the emergency department with hematemesis and were subsequently diagnosed with EGID. Accompanying allergic history, peripheral eosinophilia, and total IgE elevation were common. Despite a more severe presentation, response to medical and dietary therapy was favorable. A comprehensive review of the literature revealed 26 other cases with similar findings that reinforced the importance of prompt recognition and early dietary and immunomodulating therapy in the control of this disease.