Hepatic damage caused by flaviviruses: A systematic review

Clinical Manifestation of Arboviruses in Paediatrics

Arboviral infections in paediatric populations present unique challenges due to distinct pathophysiological mechanisms influenced by developmental and immunological differences. Commonly implicated arboviruses include dengue virus (DENV), Zika virus (ZIKV), chikungunya virus (CHIKV), West Nile virus (WNV), and yellow fever virus (YFV). These viruses exhibit specific tropisms, targeting organs such as the central nervous system (CNS), liver, and vasculature. Immune responses in children, characterised by an underdeveloped adaptive system and enhanced innate immunity, can exacerbate inflammation and increase susceptibility to severe outcomes such as dengue hemorrhagic fever (DHF), congenital Zika syndrome (CZS), and neuroinvasive complications. Maternal antibodies, antibody-dependent enhancement (ADE), and immature barriers, such as the blood-brain barrier, further contribute to disease severity. This review highlights the virological and immunological nuances of arboviral pathophysiology in paediatric patients, emphasising the need for age-specific diagnostic, therapeutic, and preventive strategies to mitigate the burden of these infections.

[Non-alphabetic viral hepatitis]

The liver is the target of various viruses that can cause significant damage, impair function and potentially threaten a patient's life. While the "alphabetic" hepatitis viruses A, B, C, D, and E are well-characterized, and their impact on liver function well-documented, many emerging and re-emerging viruses, some of which are considered by the WHO to be potential pandemic threats, also infect the liver. In this review, we describe the current state of knowledge regarding liver infections caused by major non-alphabetic hepatotropic viruses and their effects on liver functions.

Targeting PI3Kγ Pathway for Treating Dengue virus Infection

Dengue disease is a major problem worldwide, impacting millions of people annually with no specific approved treatments. The pathogenesis of dengue is a complex interplay of viral and host factors, driven in particular by an excessive inflammatory response triggered by the infection. While it has been observed that various viruses can modulate the PI3K/Akt signaling pathway to aid replication and theunderlying mechanisms remainunclear. The study aims to explore the impact of PI3Kγ inhibition during Dengue virus (DENV) infection in vivo. Experiments were performed using both wild-type (WT) and PI3Kγ knockout mice inoculated with DENV. Parameters, including survival rates, hematologic, virologic, histopathologic, and inflammatory analyzes, were evaluated. Additionally, the therapeutic potential of a selective PI3Kγ inhibitor (AS605240) was investigated in DENV-infected A129 mice. PI3Kγ deficiency resulted in lower lethality and provided protection against DENV-induced thrombocytopenia, decreased hemoconcentration, vascular permeability, and liver damage compared to DENV-infected WT littermates. In addition, PI3Kγ deficiency correlated with reduced viral replication in the blood, spleen and liver alongside decreased production of inflammatory mediators in plasma and spleen. Pharmacologic inhibition of PI3Kγ not only ameliorated DENV-induced thrombocytopenia and liver injury, but also reduced DENV replication in target organs. Treatment with AS605240 reduced the concentration of IL-6 in the spleen and plasma.This study sheds light on the significant pro-viral effects of the PI3Kγ signaling pathway during DENV infection and its central role in pathogenesis by curbing excessive DENV-induced inflammation. Inhibition of PI3Kγ shows promising host-directed target for developing novel Dengue disease therapies, offering substantial benefits to hosts.

Vascular dysfunction in hemorrhagic viral fevers: opportunities for organotypic modeling

The hemorrhagic fever viruses (HFVs) cause severe or fatal infections in humans. Named after their common symptom hemorrhage, these viruses induce significant vascular dysfunction by affecting endothelial cells, altering immunity, and disrupting the clotting system. Despite advances in treatments, such as cytokine blocking therapies, disease modifying treatment for this class of pathogen remains elusive. Improved understanding of the pathogenesis of these infections could provide new avenues to treatment. While animal models and traditional 2D cell cultures have contributed insight into the mechanisms by which these pathogens affect the vasculature, these models fall short in replicatingin vivohuman vascular dynamics. The emergence of microphysiological systems (MPSs) offers promising avenues for modeling these complex interactions. These MPS or 'organ-on-chip' models present opportunities to better mimic human vascular responses and thus aid in treatment development. In this review, we explore the impact of HFV on the vasculature by causing endothelial dysfunction, blood clotting irregularities, and immune dysregulation. We highlight how existing MPS have elucidated features of HFV pathogenesis as well as discuss existing knowledge gaps and the challenges in modeling these interactions using MPS. Understanding the intricate mechanisms of vascular dysfunction caused by HFV is crucial in developing therapies not only for these infections, but also for other vasculotropic conditions like sepsis.

The timing of minimally invasive surgery for prenatally diagnosed choledochal cysts

OBJECTIVE

There are no clear evidence-based recommendations concerning when patients with prenatally diagnosed choledochal cysts (CCs) should undergo surgery. This study was primarily designed to explore the proper timing of minimally invasive surgery for prenatally diagnosed CC patients.

METHODS

Seventy-three patients with prenatally diagnosed CC were enrolled in this study and divided into 4 subgroups according to age at surgery (15 patients in the < 1 month group, 27 in the 1-2 months group, 14 in the 2-3 months group and 17 in the > 3 months group). Eighty-five healthy infants were recruited and divided into 4 age groups (29 in the < 1 month group, 20 in the 1-2 month group, 19 in the 2-3 month group and 17 in the > 3 month group). Preoperative data were collected and compared between CC patients and healthy controls in 4 age groups. Additionally, 73 patients were divided into laparoscopic and open groups to compare postoperative recovery indices and the occurrence of complications to determine the safety and feasibility of laparoscopic CC application in neonates and young infants.

RESULTS

Twenty-one of 73 (28.8%) patients who were prenatally diagnosed with CCs experienced various clinical symptoms, and 15 of 21 (71.4%) patients experienced clinical symptoms less than 2 months after birth. No differences were found in alanine transaminase (ALT), aspartate transaminase (AST) or aspartate transaminase (APRI) levels between CC patients and controls at ≤ 1 month or 1-2 months of age (all p > 0.05), while higher levels were found in CC patients at 2-3 months or > 3 months of age (all p < 0.05). ALT, AST and DBIL levels 1 week after surgery were significantly lower than those before surgery in CC patients who underwent laparoscopic CC excision at > 2 months of age, while DBIL levels 1 week after surgery were also significantly lower than those before surgery in patients who underwent CC excision at ≤ 2 months of age. The initial oral feeding time in the laparoscopic surgery group was significantly earlier than that in the open surgery group for both CC patients who underwent CC excision at ≤ 2 months of age and those > 2 months of age (all p < 0.05). No differences were found in the rates of anastomotic leakage or stricture formation between the laparoscopic and open surgery groups at ≤ 2 months or > 2 months of age.

CONCLUSION

Most clinical symptoms attributed to CC occur less than 2 months after birth, while liver function and liver fibrosis may deteriorate after 2 months of age in patients with prenatally diagnosed CC. Laparoscopic surgery for CC in newborns and young infants (either less than or more than 2 months old) is safe and feasible and can shorten the initial oral feeding time without increasing complications such as postoperative anastomotic leakage or stricture. Thus, performing laparoscopic CC excisions within 2 months after birth in patients with prenatally diagnosed CC may be appropriate.