Molecular Pathways of Vulnerable Carotid Plaques at Risk of Ischemic Stroke: A Narrative Review.

The concept of vulnerable carotid plaques is pivotal in understanding the pathophysiology of ischemic stroke secondary to large-artery atherosclerosis. In macroscopic evaluation, vulnerable plaques are characterized by one or more of the following features: microcalcification; neovascularization; lipid-rich necrotic cores (LRNCs); intraplaque hemorrhage (IPH); thin fibrous caps; plaque surface ulceration; huge dimensions, suggesting stenosis; and plaque rupture. Recognizing these macroscopic characteristics is crucial for estimating the risk of cerebrovascular events, also in the case of non-significant (less than 50%) stenosis. Inflammatory biomarkers, such as cytokines and adhesion molecules, lipid-related markers like oxidized low-density lipoprotein (LDL), and proteolytic enzymes capable of degrading extracellular matrix components are among the key molecules that are scrutinized for their associative roles in plaque instability. Through their quantification and evaluation, these biomarkers reveal intricate molecular cross-talk governing plaque inflammation, rupture potential, and thrombogenicity. The current evidence demonstrates that plaque vulnerability phenotypes are multiple and heterogeneous and are associated with many highly complex molecular pathways that determine the activation of an immune-mediated cascade that culminates in thromboinflammation. This narrative review provides a comprehensive analysis of the current knowledge on molecular biomarkers expressed by symptomatic carotid plaques. It explores the association of these biomarkers with the structural and compositional attributes that characterize vulnerable plaques.

Allograft Fibrosis After Pediatric Liver Transplantation: Incidence, Risk Factors, and Evolution.

Allograft fibrosis (AF) after pediatric liver transplantation (pLT) is frequent, but its dynamics are unclear. Our aim was to assess the evolution and risk factors of AF after pLT. A retrospective single-center analysis of pLT patients with a follow-up of ≥5 years who underwent protocol liver biopsies at 6 months, 1 year, 2 years, 5 years, and 10 years was performed. Fibrosis was assessed using the METAVIR and Ishak systems and the liver allograft fibrosis score (LAFs). Of 219 pLTs performed from 2008 to 2018, 80 (36.5%) pLTs were included, and 320 biopsies were reviewed. At 6 months after pLT, fibrosis was found in 54 (67.5%) patients by the METAVIR/Ishak systems and in 59 (73.8%) by the LAFs (P = 0.65). By 5 years, AF was detected in 67 (83.8%), 69 (86.3%), and 72 (90%) specimens using the METAVIR, Ishak, and LAFs systems, respectively (P = 0.54); mild (METAVIR, 51 [63.8%]; Ishak, 60 [75%]; LAFs, 65 [81.2%]) and moderate (METAVIR, 16 [20%]; Ishak, 9 [11.9%]; LAFs, 7 [8.8%]) stages were detected, but severe fibrosis was not found (P = 0.09). In the LAFs, fibrosis involved the portal (85%), sinusoidal (15%), and centrolobular (12%) areas. Of 18 patients with 10-year protocol biopsies, AF was present in 16 (90%), including 1 (5.5%) with severe fibrosis. In all systems, 36.3% of patients showed fibrosis progression from 2 years to 5 years after LT, but they remained stable at the 10-year biopsies without clinical implications. In multivariate analysis, only donor age >40 years was a risk factor for moderate AF at 5 years after LT (odds ratio, 8.3; 95% confidence interval, 1.6-42.1, P = 0.01). Cold ischemia time (CIT) >8 hours was associated with portal (P < 0.001)/sinusoidal fibrosis (P = 0.04), donor age >40 years was associated with sinusoidal (P = 0.01)/centrilobular (P = 0.04) fibrosis, and low tacrolimus trough level within 1 year after LT was associated with centrilobular fibrosis (P = 0.02). AF has a high incidence after pLT, occurring early after transplantation. In most cases, AF is mild or moderate and remains stable in the long run without clinical implications. Donor selection, short CIT, and immunosuppression adherence are crucial to reducing the risk of advanced AF.

Five-Year Inpatient Management of Teenagers With Anorexia Nervosa: Focus on Nutritional Issues.

OBJECTIVES: In patients with Anorexia Nervosa (AN) malnutrition can lead to life-long nutritional treatments. The refeeding process can combine natural feeding (NF) with specific nutritional strategies, including oral nutritional supplements (ONS) and nasogastric feeding (NGF). Aims of the present study were to assess the efficacy of hospital protocol and identify the most effective inpatient nutritional strategies for weight restoration. METHODS: All patients hospitalized from April 2015 to April 2020 were enrolled. According to hospital protocol, NF was proposed to all patients; ONS were combined with NF if caloric intake was <70% of the requirements and NGF was added if caloric intake did not reach 30% in the first week from admission. RESULTS: Overall, 186 patients [M = 20; median age 14 (interquartile range 1316)] were included. Nutritional issues were the main indication to admission (56.6%). A significant effect of combination treatment, with a shorter duration of hospitalization when using ONS with NGF in addition to NF was found (ß: -20.28 [95% confidence interval -34.92:-5.65], P  < 0.001). Only one patient showed a significant but limited increase of liver enzymes. CONCLUSIONS: We provide a safe and effective standardized protocol to treat the malnutrition of teenagers with AN in an inpatient setting. Malnutrition was the most important cause of admission, and more than half of the patients admitted were severely malnourished. The combination of NF, ONS, and NGF was the most effective strategy to achieve the weight restoration; however, this result should be validated on larger series of patients treated with NGF and NF.

The Role of the Coagulation System in Peripheral Arterial Disease: Interactions with the Arterial Wall and Its Vascular Microenvironment and Implications for Rational Therapies.

Peripheral artery disease (PAD) is a clinical manifestation of atherosclerotic disease with a large-scale impact on the economy and global health. Despite the role played by platelets in the process of atherogenesis being well recognized, evidence has been increasing on the contribution of the coagulation system to the atherosclerosis formation and PAD development, with important repercussions for the therapeutic approach. Histopathological analysis and some clinical studies conducted on atherosclerotic plaques testify to the existence of different types of plaques. Likely, the role of coagulation in each specific type of plaque can be an important determinant in the histopathological composition of atherosclerosis and in its future stability. In this review, we analyze the molecular contribution of inflammation and the coagulation system on PAD pathogenesis, focusing on molecular similarities and differences between atherogenesis in PAD and coronary artery disease (CAD) and discussing the possible implications for current therapeutic strategies and future perspectives accounting for molecular inflammatory and coagulation targets. Understanding the role of cross-talking between coagulation and inflammation in atherosclerosis genesis and progression could help in choosing the right patients for future dual pathway inhibition strategies, where an antiplatelet agent is combined with an anticoagulant, whose role, despite pathophysiological premises and trials' results, is still under debate.

Diagnosis and management of cerebral venous sinus thrombosis in children: a single-center retrospective analysis.

PURPOSE: Cerebral venous thrombosis (CVT) is a rare disease in children, characterized by partial or total occlusion of blood flow in the cerebral venous system. The aim of this study is to describe clinical presentation, neuroimaging features, therapeutic management, and outcome of children with CVT. METHODS: We retrospectively analyzed the data, including clinical manifestations, laboratory data, neurological findings, and treatment of children with radiologically confirmed CVT, admitted between January 2010 and March 2020 to our hospital. Cases of CVT complicating brain surgery were excluded. RESULTS: We enrolled 24 children with CVT. Infection was the main etiology (58.3%), followed by trauma in 16.7% of cases. In the remaining 25% of cases, the cause was identified only in one patient presenting a thrombophilic factor. The most frequent site of thrombosis was the superficial venous system (86.8%), with multiple localizations disclosed in 79% of patients. All children received anticoagulant therapy with low molecular weight heparin (LMWH). One patient died for systemic complications of an underlying disease. No patient developed hemorrhagic events during the therapy, lasting from 35 to 360 days (mean 86 days). In all but one surviving patients (22 out of 24), recanalization of the sinus was observed at AngioMRI performed during follow-up. No neurological complications of CVT were recorded (mean follow-up: 1.5 year). CONCLUSIONS: CVT may present with subtle and unspecific clinical manifestations in children. High level of suspicion should be kept in trauma and sinusitis. Anticoagulation treatment is safe and effective and should be promptly started to improve outcome.

Establishment of a Seronegative Occult Infection With an Active Hepatitis B Virus Reservoir Enriched of Vaccine Escape Mutations in a Vaccinated Infant After Liver Transplantation.

We describe the establishment of a seronegative occult hepatitis B virus (HBV) infection (OBI) in a successfully vaccinated infant who underwent liver transplantation from an donor positive for antibody to hepatitis B core antigen (anti-HBc). The use of highly sensitive droplet digital polymerase chain reaction assays revealed a not negligible and transcriptionally active intrahepatic HBV reservoir (circular covalently closed DNA, relaxed circular DNA, and pregenomic RNA: 5.6, 2.4, and 1.1 copies/1000 cells, respectively), capable to sustain ongoing viral production and initial liver damage. Next-generation sequencing revealed a peculiar enrichment of hepatitis B surface antigen vaccine-escape mutations that could have played a crucial role in OBI transmission. This clinical case highlights the pathobiological complexity and the diagnostic challenges underlying OBI.

Congenital Hypopigmentary Disorders with Multiorgan Impairment: A Case Report and an Overview on Gray Hair Syndromes.

The term congenital hypopigmentary disorders refers to a wide group of heterogeneous hereditary diseases, clinically characterized by inborn pigmentary defects of the iris, hair, and/or skin. They include Gray Hair Syndromes (GHSs), a rare group of autosomal recessive genodermatosis hallmarked by inborn silvery gray hair. GHSs encompass Griscelli, Chediak⁻Higashi, Elejalde, and Cross syndromes, which are all characterized by a broad spectrum of severe multisystem disorders, including neurological, ocular, skeletal, and immune system impairment. In this manuscript, we describe in detail the clinical, trichoscopic, and genetic features of a rare case of Griscelli syndrome; moreover, we provide an overview of all the GHSs known to date. Our report highlights how an accurate clinical examination with noninvasive methods, like trichoscopy, may play a crucial rule in diagnosis of rare and potentially lethal genetic syndromes such as Griscelli syndrome, in which timely diagnosis and therapy may modify the clinical course, quality of life, and likelihood of survival.

Liver Transplantation and Gut Microbiota Profiling in a Child Colonized by a Multi-Drug Resistant Klebsiella pneumoniae: A New Approach to Move from Antibiotic to "Eubiotic" Control of Microbial Resistance.

The increase of microorganisms multi-drug resistant (MDR) to antibiotics (ATBs) is becoming a global emergency, especially in frail subjects. In chronic liver disease (LD) with indications for liver transplantation (LT), MDR colonization can significantly affect the LT outcome. However, no clear guidelines for microbial management are available. A novel approach toward MDR-colonized patients undergoing LT was developed at our Center refraining from ATBs use during the transplant waiting list, and use of an intensive perioperative prophylaxis cycle. This study aimed to couple clinical evaluation with monitoring of gut microbiota in a pediatric LD patient colonized with MDR Klebsiella pneumoniae (KP) who underwent LT. No peri-transplant complications were reported, and a decontamination from the MDR bacteria occurred during follow-up. Significant changes in gut microbiota, especially during ATB treatment, were reported by microbiota profiling. Patterns of Klebsiella predominance and microbiota diversity revealed opposite temporal trends, with Klebsiella ecological microbiota niches linked to ATB-driven selection. Our infection control program appeared to control complications following LT in an MDR-KP-colonized patient. The perioperative ATB regimen, acting as LT prophylaxis, triggered MDR-KP overgrowth and gut dysbiosis, but buffered infectious processes. Mechanisms modulating the gut ecosystem should be taken into account in MDR colonization clinical management.

Autoimmune liver diseases and inflammatory bowel diseases in children: current issues and future perspectives.

Inflammatory bowel diseases (IBDs) represent a group of intestinal disorders with a chronic and relapsing inflammation of the gut, and with a potential risk of systemic involvement of other organs and systems. Over the pediatric age, an incidence higher than 20% of developing extraintestinal manifestation during follow-up has been reported. The liver and the biliary system are frequently involved, and primary sclerosing cholangitis (PSC) is the most predominant entity with an incidence rate of 6.4-7.8% in children. PSC recognizes a multifactorial pathogenesis, and so far a not fully known mechanism for this association. The peculiar phenotype and the distinct clinical course of patients with IBD and PSC-associated make this 'linkage' an attractive study model to better understand mechanisms underlying these diseases. Approaching to these patients is complex and multidisciplinary, and a unique therapeutic strategy has not been standardized yet. New medications are being studied; however, further studies are needed to fully understand the pathogenesis and to improve the care of these patients. The aim of this paper is to review the recent literature regarding hepatobiliary involvement in IBD patients, with particular attention to PSC, and to provide the latest information for a correct diagnosis and appropriate management.

Anthracycline-induced cardiotoxicity in patients with paediatric bone sarcoma and soft tissue sarcoma.

OBJECTIVES: Anthracycline cardiotoxicity is an important side-effect in long-term childhood cancer survivors. We evaluated the incidence of and factors associated with anthracycline cardiotoxicity in a population of patients diagnosed with bone or soft tissue sarcoma. Materials and methods We retrospectively enrolled patients diagnosed with bone or soft tissue sarcoma, from 1995 to 2011, treated with anthracycline chemotherapy at our Centre and with a follow-up echocardiography carried out ⩾3 years from cardiotoxic therapy completion. Cardiac toxicity was graded using Common Terminology Criteria for Adverse Events version 4.0. RESULTS: A total of 82 patients were eligible. The median age at treatment was 11.9 years (1.44-18). We evaluated the median cumulative anthracycline dose, age at treatment, sex, thoracic radiotherapy, hematopoietic stem cell transplantation, and high-dose cyclophosphamide treatment as possible risk factors for cardiotoxicity. The median cumulative anthracycline dose was 390.75 mg/m2 (80-580). Of the 82 patients, 12 (14.6%) developed cardiotoxicity with grade ⩾2 ejection fraction decline: four patients were asymptomatic and did not receive any treatment; six patients were treated with pharmacological heart failure therapy; one patient with severe cardiomyopathy underwent heart transplantation and did not need any further treatment; and one patient died while waiting for heart transplantation. The median time at cardiac toxicity, from the end of anthracycline frontline chemotherapy, was 4.2 years (0.05-9.6). Cumulative anthracycline dose ⩾300 mg/m2 (p 0.04) was the only risk factor for cardiotoxicity on statistical analyses. CONCLUSIONS: In our population, the cumulative incidence of cardiotoxicity is comparable to rates in the literature. This underlines the need for primary prevention and lifelong cardiac toxicity surveillance programmes in long-term childhood cancer survivors.

Prospective study of hepatitis B virus reactivation in patients with hematological malignancies.

BACKGROUND AND AIM: The best strategy for managing patients with resolved hepatitis B virus infection (HBsAg negative, anti-HBc antibodies positive with or without anti-HBs antibodies) and hematological malignancies under immunosuppressive therapies has not been defined. The aim of this study was to prospectively analyze the risk of hepatitis B virus reactivation in these patients. MATERIAL AND METHODS: Twenty-three patients (20 positive for anti-HBs) were enrolled. Eleven patients underwent hematopoietic stem cell transplantation (autologous in 7 cases, allogeneic in 4 cases) while the remaining 12 were treated with immunosuppressive regimens (including rituximab in 9 cases). RESULTS: During the study no patient presented acute hepatitis. However, three anti-HBc/anti-HBs positive patients who were treated with allogeneic hematopoietic stem cell transplantation demonstrated hepatitis B virus reactivation within 12 months from transplant. No one of the remaining patients showed hepatitis B virus reverse seroconversion. CONCLUSIONS: Allogeneic hematopoietic stem cell transplantation is a high risk condition for late hepatitis B virus reactivation in patients with resolved infection. Reverse seroconversion seems to be a rare event in anti-HBc/anti-HBs positive patients submitted to autologous hematopoietic stem cell transplantation or systemic chemotherapy with or without rituximab.

Digital radiography for determination of primary tooth length: in vivo and ex vivo studies.

BACKGROUND: Methods for determining the root canal length of the primary tooth should yield accurate and reproducible results. In vitro studies show some limitations, which do not allow their findings to be directly transferred to a clinical situation. AIM: To compare the accuracy of radiographic tooth length obtained from in vivo digital radiograph with that obtained from ex vivo digital radiograph. METHOD: Direct digital radiographs of 20 upper primary incisors were performed in teeth (2/3 radicular resorption) that were radiographed by an intraoral sensor, according to the long-cone technique. Teeth were extracted, measured, and mounted in a resin block, and then radiographic template was used to standardise the sensor-target distance (30 cm). The apparent tooth length (APTL) was obtained from the computer screen by means of an electronic ruler accompanying the digital radiography software (CDR 2.0), whereas the actual tooth length (ACTL) was obtained by means of a digital calliper following extraction. Data were compared to the ACTL by variance analysis and Pearson's correlation test. RESULTS: The values for APTL obtained from in vivo radiography were slightly underestimated, whereas those values obtained from ex vivo were slightly overestimated. No significance was observed (P ≤ 0.48) between APTL and ACTL. CONCLUSION: The length of primary teeth estimated by in vivo and ex vivo comparisons using digital radiography was found to be similar to the actual tooth length.

End-of-life care in pediatric neuro-oncology.

BACKGROUND: The management of children with cancer during the end-of-life (EOL) period is often difficult and requires skilled medical professionals. Patients with tumors of the central nervous system (CNS) with relapse or disease progression might have additional needs because of the presence of unique issues, such as neurological impairment and altered consciousness. Very few reports specifically concerning the EOL period in pediatric neuro-oncology are available. PROCEDURE: Among all patients followed at our center during the EOL, we retrospectively analyzed data from 39 children and adolescents with brain tumors, in order to point out on their peculiar needs. RESULTS: Patients were followed-up for a median time of 20.1 months. Eighty-two percent were receiving only palliative therapy before death. Almost half the patients (44%) died at home, while 56% died in a hospital. Palliative sedation with midazolam was performed in 58% of cases; morphine was administered in 51.6% of cases. No patient had uncontrolled pain. CONCLUSIONS: The EOL in children with advanced CNS cancer is a period of active medical care. Patients may develop complex neurological symptoms and often require long hospitalization. We organized a network-based collaboration among the reference pediatric oncology center, other pediatric hospitals and domiciliary care personnel, with the aim to ameliorate the quality of care during the EOL period. In our cohort, palliative sedation was widely used while no patients died with uncontrolled pain. A precise process of data collection and a better sharing of knowledge are necessary in order to improve the management of such patients.

Diffuse intrinsic pontine glioma in children and adolescents: a single-center experience.

BACKGROUND: Patients with diffuse intrinsic pontine glioma (DIPG) have a very poor prognosis. Only radiotherapy (XRT) has proven to be effective in delaying the disease progression. Several chemotherapy schedules have been applied so far, but none demonstrated significant improvements in progression and survival. METHODS: We retrospectively analyzed the clinical data of children diagnosed with DIPG at our center (Pediatric Hospital "Regina Margherita," Turin, Italy) between 1999 and 2013. Progression-free survival (PFS) and overall survival (OS) were used to describe the outcomes. RESULTS: Twenty-four children were included in our report. Patients diagnosed before March 2003 (n = 12) were treated with XRT and vincristine (VCR); the remaining 12 patients received XRT and temozolomide (TMZ). Progression-free survival was 18.8 % at 1 year (SE = 7.6 %), while overall survival was 44.1 % at 1 year (SE = 9.9 %). Median PFS was 8.1 months, whereas median OS was 11.2 months. No statistically significant difference in PFS or OS was evidenced between the two treatment groups. CONCLUSION: Radiotherapy followed by VCR or TMZ allows obtaining results that are in line with previous reports, with no advantages over other similar treatment schedules. DIPGs are challenging tumors with a dismal outcome. Further research and newer therapies are urgently needed in order to achieve improvements in survival.

Paraneoplastic Cerebellar Degeneration Associated with Breast Cancer: A Case Report and a Narrative Review.

Paraneoplastic neurological syndromes (PNSs) are an uncommon complication of cancer, affecting nearby 1/10,000 subjects with a tumour. PNSs can involve all the central and peripheral nervous systems, the muscular system, and the neuromuscular junction, causing extremely variable symptomatology. The diagnosis of the paraneoplastic disease usually precedes the clinical manifestations of cancer, making an immediate recognition of the pathology crucial to obtain a better prognosis. PNSs are autoimmune diseases caused by the expression of common antigens by the tumour and the nervous system. Specific antibodies can help clinicians diagnose them, but unfortunately, they are not always detectable. Immunosuppressive therapy and the treatment of cancer are the cornerstones of therapy for PNSs. This paper reports a case of PNSs associated with breast tumours and focuses on the most common paraneoplastic neurological syndromes. We report a case of a young female with a clinical syndrome of the occurrence of rigidity in the right lower limb with postural instability with walking supported and diplopia, with a final diagnosis of paraneoplastic cerebellar degeneration and seronegative rigid human syndrome associated with infiltrating ductal carcinoma of the breast.

Safety and effectiveness of oral anticoagulants in patients with atrial fibrillation and stage 4 chronic kidney disease: a real-world experience.

It is still uncertain whether direct oral anticoagulants (DOACs) perform better than vitamin K antagonists (VKAs) in subjects with non-valvular atrial fibrillation (NVAF) and advanced chronic kidney disease (CKD). The aim of the study was to compare safety and effectiveness of DOACs and VKAs in patients with NVAF and stage 4 CKD (creatinine clearance 15-29 mL/min). We searched the hospital databases of two academic centers to retrospectively identify patients with stage 4 CKD who were on treatment with DOACs or VKAs for NVAF. Safety was the primary outcome of the study and was assessed in terms of incidence of major bleeding (MB). Secondary outcomes were clinically relevant non-major bleeding (CRNMB) and death for any cause. A total of 176 patients (102 on DOACs and 74 on VKAs) were found and included in the analysis. The incidence rate of MB was not statistically different between groups (8.6 per 100 patients-year in the DOAC group and 5.6 per 100 patients-year in the VKA group). Rates of IS/SSE and CRNMB were statistically similar in the two treatment groups, as well. There were less deaths for any cause in the DOAC group than in the VKA group (8.6 and 15.8 per 100 patients-year, respectively), but the difference was not statistically significant. This study found no difference in terms of safety and effectiveness between patients with NVAF and stage 4 CKD treated with DOACs and VKAs. Larger prospective or randomized studies are needed to confirm these findings.

An integrated multi-tool analysis contributes elements to interpreting unclassified factor IX missense variants associated with haemophilia B.

BACKGROUND: Dissection of genotype-phenotype relationships in haemophilia B (HB) is particularly relevant for challenging (mild HB) or for HB-associated but unclassified factor IX (FIX) missense variants. Here, the identification of a FIX missense variant associated with mild HB, reported but unclassified, prompted a multiple-level approach to contribute elements to interpret unclassified HB-associated FIX missense variants. METHODS: Molecular modelling of wild-type (WT) and V92A FIX variants, expression studies in HEK293 cells with evaluation of protein (ELISA, Western blotting) and activity (aPTT-based/chromogenic assays) levels after recombinant expression, and multiple prediction tools. RESULTS: The F9(NM_000133.4):c.275T>C (p.V92A) variant was found in a mild HB patient (antigen, 45.4 U/dl; coagulant activity, 23.6 IU/dl; specific activity, 0.52). Newly generated molecular models showed alterations in Gla/EGF1-EGF2 domain conformation impacting on Ca++ affinity and protein-protein interactions with FXIa. Multi-tool analysis indicated a moderate impact on protein structure/function of the valine-to-alanine substitution, in accordance with patient's and modelling data. Expression studies on the V92A variant showed a specific activity (0.49±0.07; WT, 1.0±0.1) recapitulating that of the natural variant, and pointed toward a moderate activation impairment as the main determinant underlying the p.V92A defect. The validated multi-tool approach, integrated with evidence-based data, was challenged on a panel (n=9) of unclassified FIX missense variants, which resulted in inferred protein (secretion/function) outputs and HB severity. CONCLUSIONS: The rational integration of multi-tool and multi-parameter analyses contributed elements to interpret genotype/phenotype relationships of unclassified FIX missense variants, with implications for diagnosis, management and treatment of HB patients, and potentially translatable into other human disorders.

Acute Hepatitis of Unknown Origin in Children: Analysis of 17 Cases Admitted to the Bambino Gesù Children's Hospital in Rome.

This study described 17 cases of children admitted to the Bambino Gesù Children's Hospital with acute hepatitis of unknown origin between mid-April and November 2022. Following the World Health Organization's working case definition of probable cases, 17 children, with a median age of 2.1 years (interquartile range: 1.0-7.1), presenting with acute hepatitis non-AE, with serum transaminase >500 IU/L, were included in the study. A pre-specified set of microbiological tests was performed on different biological specimens for all pediatric patients. All patients resulted negative for the common hepatotropic viruses. The most common pathogen detected in blood specimens was human-herpes-virus-7 (52.9%). Adenovirus was detected more frequently in stool specimens (62.5%) than in respiratory (20.0%) or blood samples (17.6%). Regarding Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, one child tested positive two days after admission, while antibodies against spike and nucleoprotein were present in 82.3% of patients. A co-pathogen detection was observed in 94.1% of children. Overall, 16 children recovered without clinical complications, while one patient required liver transplantation. In these cases of acute hepatitis of unknown origin, adenovirus was mainly detected in stool samples. A co-pathogen detection was also frequently observed, suggesting that the etiology of this acute hepatitis is most probably multifactorial.

Congenital prothrombin deficiency: an update.

Prothrombin (factor II [FII]) deficiency is a rare inherited coagulation disorder, having a prevalence of approximately 1 in 2,000,000. Two phenotypes can be distinguished: (1) true hypoprothrombinemia (type I deficiency), characterized by concomitantly low levels of the zymogen antigen; and (2) dysprothrombinemia (type II deficiency), characterized by the normal or near-normal synthesis of a dysfunctional protein. In the latter case, recent studies showed that particular mutations in the catalytic domain of active thrombin can even impair the enzyme interaction with antithrombin, favoring thromboembolic diseases. In some cases, hypoprothrombinemia associated with dysprothrombinemia was also described in compound heterozygous defects. Prothrombin is essential for the development of mammalian organisms. No living patient with undetectable plasma prothrombin has been reported to date. Prothrombin is encoded by a ≈21 kb gene located on chromosome 11 and containing 14 exons. Thirty-nine different mutations have been identified and characterized in prothrombin deficiency. Many of these are present in the catalytic site, whereas some involve regulatory domains, such as the anion-binding exosite I, the Na+-binding loop, and the light A-chain. Most hypoprothrombinemia-associated mutations are missense, but nonsense mutations leading to stop codons and one single nucleotide deletion have also been identified. Finally, recent developments in the therapy of congenital prothrombin deficiency are presented and discussed.

Transient elastography is a useful noninvasive tool for the evaluation of fibrosis in paediatric chronic liver disease.

BACKGROUND: Outcome of liver disease in children is mainly determined by severity and progression of liver fibrosis. Liver biopsy is the accepted standard for evaluating fibrosis but is limited by the need for sedation in children, sampling error, and risks including bleeding. The aim of the present study was to compare tools for noninvasive assessment of liver fibrosis in a paediatric cohort. METHODS: Children undergoing liver biopsy for chronic liver disease were recruited and underwent transient elastography (TE). Liver biopsies were scored by a hepatohistopathologist from F0 (no fibrosis) to F4 (cirrhosis). TE was compared with biopsy score. RESULTS: During the study period, 104 children (62 boys) were enrolled (median age 13.6 years). Diagnosis was autoimmune liver disease in 27; nonalcoholic fatty liver disease in 37; posttransplant in 16; hepatitis B/C in 8; Wilson disease in 5; and the remainder, miscellaneous. TE was successful in all but 7 patients and was a good discriminator of significant fibrosis (≥ F2) (P < 0.001), severe fibrosis (≥ F3) (P < 0.001), and cirrhosis (F4) (P = 0.003). The area under the receiver operating characteristic curve for the prediction of ≥ F2, ≥ F3, and F4 using TE was 0.78, 0.79, and 0.96, respectively. TE performed best in children with autoimmune liver disease and in those posttransplant. CONCLUSIONS: The present study demonstrates that TE is a reliable tool in distinguishing different stages of liver fibrosis in paediatric patients. Thus, TE may serve as a useful adjunct to liver biopsy for diagnostic purposes providing a reliable method of noninvasively monitoring liver disease progression in children.