RNA-sequencing-based detection of human viral pathogens in cerebrospinal fluid and serum samples from children with meningitis and encephalitis.

Encephalitis and meningitis are notable global public health concerns, especially among infants or children. Metagenomic next-generation sequencing (mNGS) has greatly advanced our understanding of the viruses responsible for these diseases. However, the detection rate of the aetiology remains low. We conducted RNA sequencing and virome analysis on cerebrospinal fluid (CSF) and serum samples commonly used in the clinical diagnosis to detect viral pathogens. In total, 226 paired CSF and serum samples from 113 children with encephalitis and meningitis were enrolled. The results showed that the diversity of viruses was higher in CSF, with a total of 12 viral taxa detected, including one case each of herpesvirus, coronavirus and enterovirus, and six cases of adenovirus related to human diseases. In contrast, the Anelloviridae was the most abundant viral family detected in serum, and only a few samples contained human viral pathogens, including one case of enterovirus and two cases of adenovirus. The detection rate for human viral pathogens increases to 10.6 %(12/113) when both types of samples are used simultaneously, compared to CSF along 7.9 % (9/113) or serum alone 2.6 % (3/113). However, we did not detect these viruses simultaneously in paired samples from the same case. These results suggest that CSF samples still have irreplaceable advantages for using mNGS to detect viruses in patients with meningitis and encephalitis, and serum can supplement to improve the detection rate of viral encephalitis and meningitis. The findings of this study could help improve the etiological diagnosis, clinical management and prognosis of patients with meningitis and encephalitis in children.

Integrin α4ß1/VCAM-1 Interaction Evokes Dynamic Cell Aggregation Between Immune Cells and Human Lung Microvascular Endothelial Cells at Infectious Hemolysis.

Bacterial and viral infection is a common cause of pneumonia, respiratory failure, and even acute respiratory distress syndrome. Increasing evidence indicates that red blood cells (RBCs) may contribute to immune response and inflammation. However, the precise molecular mechanisms that link RBC and hemolysis to the development and progression of inflammatory pathologies are not entirely understood. In this study, we used bacterial endotoxin, lipopolysaccharide (LPS), to mimic an infectious hemolysis and found that RBCs dynamically regulated cell aggregation between immune cells and human lung microvascular endothelial cells (HLMVEC). When RBCs were treated with LPS, integrin α4ß1 was increased and was accompanied by cytokines and chemokines release (TNF-α, IL-1ß, IL-6, IL-8, IFN-γ, CXCL12, CCL5, CCL7 and CCL4). Upon α4ß1 elevation, RBCs not only facilitated mature monocyte derived dendritic cell (mo-DCs) adhesion but also promoted HLMVEC aggregation. Furthermore, co-culture of the supernatant of LPS pre-treated RBCs with mo-DCs could promote naïve CD4 T cell proliferation. Notably, the filtered culture from LPS-lysed RBCs further promoted mo-DCs migration in a concentration dependent manner. From a therapeutic perspective, cyclic peptide inhibitor of integrin α4ß1 combined with methylprednisolone (α4ß1/Methrol) remarkably blocked RBCs aggregation to mo-DCs, HLMVEC, or mo-DCs and HLMVEC mixture. Moreover, α4ß1/Methrol dramatically reduced mo-DCs migration up-regulated glucocorticoid-induced leucine zipper in mo-DCs, and ultimately reversed immune cell dysfunction induced by hemolysis. Taken together, these results indicate that integrin α4ß1 on RBCs could mediate cell-cell interaction for adaptive immunity through influencing cell adhesion, migration, and T cell proliferation.

Penicilliosis marneffei in HIV negative children: three case reports.

This study aimed to report the clinical characteristics of penicilliosis marneffei (PSM) in three children negative to HIV. Three children were diagnosed with PSM in the Department of Emergency Medicine, Hunan Children's Hospital between February 2016 to July 2020. The clinical characteristics, laboratory findings, and concomitant diseases were recorded, and the related literatures were reviewed. The clinical characteristics and treatment of PSM were reported according to our experience and literature review. The initial symptom was right lower limb mass in 1 child (first) who developed fever and cough about 1 month later and then was misdiagnosed with tuberculosis. The other child (second) had a fever, reductions in red blood cells, white blood cells and platelets, hepatosplenomegaly and lymphadenectasis. The third child had fever, jaundice, multiple organ dysfunction syndrome (MODS), hepatosplenomegaly and lymphadenectasis. The first child (Case 1) had STAT1 gene mutation on genetic examination, and the second child (Case 2) had history of onychomycosis and oral ulcer, the third child (Case 3) had STAT3 gene mutation on genetic examination, diagnosed with Hyperimmunoglobulin E syndromes (HIES). PSM was confirmed in all cases by the culture bone marrow. All three cases were diagnosed through medulloculture. Case 1 and Case 2 also had lymph node biopsy. Case 3 had sputum culture and bronchoalveolar lavage fluid (BALF). The first child was intravenously administered with voriconazole and amphotericin B liposomes, and orally administered with itraconazole for maintenance therapy, which was discontinued 1 year later. The second child was administered with voriconazole intravenously and thereafter orally for a total of 7 months. Recurrence was not observed. The third child was given amphotericin B for 2 days (discontinued due to liver dysfunction), and intravenous voriconazole for 4 days. The patient gave up therapy finally. In conclusion, HIV negative children can also develop PSM, and may be related to the STAT1/STAT3 gene mutation. For children having no response to antibiotic or antiviral therapy, bacterial/fungal culture or biopsy should be performed as soon as possible to confirm the diagnosis, and physicians should actively identify the underlying diseases of PSM patients, which is beneficial for the early diagnosis, early treatment and improvement of prognosis.

Kikuchi's disease with hemophagocytic lymphohistiocytosis: A case report and literature review.

INTRODUCTION: Kikuchi's disease (KD) is a rare form of necrotizing lymphadenitis that rarely occurs in association with hemophagocytic lymphohistiocytosis (HLH) in children. PATIENT CONCERNS: We report the case of a 4-year-5-month-old boy who suffered from fever, cervical lymphadenopathy, pancytopenia, hypertriglyceridemia, splenomegaly, low NK cell activity. DIAGNOSES: A diagnosis of KD with HLH was made based on the results of biopsy of cervical lymph node and HLH-2004 trial guidelines. INTERVENTIONS: The patient was treated with corticosteroids, cyclosporine, etoposide, continuous hemodiafiltration (HDF), and plasma exchange (PE). OUTCOMES: He showed a complete response to therapy, and his condition gradually improved. He was discharged on day 45 after admission due to his good recovery status. CONCLUSION: HLH can be associated with KD, especially in childhood, and may have an aggressive clinical course. Continuous HDF and PE and chemotherapy should be reserved for those patients who fail to respond to IVIG and corticosteroids.

[Diagnostic value of high mobility group box 1 for acute appendicitis in children].

OBJECTIVE: To evaluate the value of high mobility group box 1(HMGB1) in the diagnosis of pediatric acute appendicitis. METHODS: The children with acute abdomen who had a diagnosis of suspected acute appendicitis between January and July 2013 and 25 healthy children were enrolled in this study. Serum HMGB1 levels were measured using ELISA on admission. The patients were classified into 2 groups according to surgery confirmation or pathological results: appendicitis (n=28) and non-appendicitis (n=35). RESULTS: Serum HMGB1 levels and WBC in the appendicitis and non-appendicitis groups were significantly higher than in the healthy children group (P<0.01). The appendicitis group showed more increased serum HMGB1 levels compared with the non-appendicitis group (median: 32.9 ng/mL vs 22.0 ng/mL; P<0.01). For a diagnosis of acute appendicitis, the sensitivity and specificity of serum HMGB1 was 71.4% and 82.9% respectively at the best cutoff of 28.0 ng/mL, with the accuracy of 77.8% and the area under the curve of 0.765 (95%CI 0.638-0.893). CONCLUSIONS: HMGB1 may play a role in the diagnosis of pediatric acute appendicitis.