Paediatric porto-sinusoidal vascular disease: Two different clinical phenotypes with subtle histological differences.

BACKGROUND AND AIMS: In paediatrics, porto-sinusoidal vascular disease (PSVD) is relatively unknown and probably underdiagnosed. We aimed to describe clinical phenotypes, histology and outcome of children diagnosed with PSVD. METHODS: Retrospective multicentre study of children diagnosed with PSVD. Diagnosis of PSVD was based on histopathology reports; liver specimens were re-evaluated by two expert liver pathologists. RESULTS: Sixty two children diagnosed with PSVD (M/F = 36/26, median age 6.6 years, range 3.3-10.6), from 7 centres, were included. Thirty-six presented with non-cirrhotic portal hypertension, PH, (PH-PSVD Group = 58%) while 26 had a liver biopsy because of chronic elevation of transaminases without PH (noPH-PSVD Group = 42%). On histology review, the two groups differed for the prevalence of obliterative portal venopathy (more prevalent in PH-PSVD, p = 0.005), and hypervascularised portal tracts (more common in noPH-PSVD, p = 0.039), the other histological changes were equally distributed. At multivariate analysis, platelet count ≤185 000/mm3 was the only independent determinant of PH (p < 0.001). After a median follow-up of 7 years (range 3.0-11.2), in PH-PSVD group 3/36 (8%) required TIPS placement, 5/36 (14%) developed pulmonary vascular complications of PH, and 7/36 (19%) required liver transplantation. In noPH-PSVD none progressed to PH nor had complications. CONCLUSIONS: Paediatric patients with PSVD present with two different clinical phenotypes, one characterised by PH and one by chronic elevation of transaminases without PH. PSVD should be included among the conditions causing isolated hypertransaminasaemia. On histology, the differences between the two groups are subtle. Medium-term outcome is favourable in patients without PH; progression of the disease is observed in those with PH.

Energy dissipation during expiration and ventilator-induced lung injury: an experimental animal study.

The amount of energy delivered to the respiratory system is recognized as a cause of ventilator-induced lung injury (VILI). How energy dissipation within the lung parenchyma causes damage is still a matter of debate. Expiratory flow control has been proposed as a strategy to reduce the energy dissipated into the respiratory system during expiration and, possibly, VILI. We studied 22 healthy pigs (29 ± 2 kg), which were randomized into a control (n = 11) and a valve group (n = 11), where the expiratory flow was controlled through a variable resistor. Both groups were ventilated with the same tidal volume, positive end-expiratory pressure (PEEP), and inspiratory flow. Electric impedance tomography was continuously acquired. At completion, lung weight, wet-to-dry ratios, and histology were evaluated. The total mechanical power was similar in the control and valve groups (8.54 ± 0.83 J·min-1 and 8.42 ± 0.54 J·min-1, respectively, P = 0.552). The total energy dissipated within the whole system (circuit + respiratory system) was remarkably different (4.34 ± 0.66 vs. 2.62 ± 0.31 J/min, P < 0.001). However, most of this energy was dissipated across the endotracheal tube (2.87 ± 0.3 vs. 1.88 ± 0.2 J/min, P < 0.001). The amount dissipated into the respiratory system averaged 1.45 ± 0.5 in controls versus 0.73 ± 0.16 J·min-1 in the valve group, P < 0.001. Although respiratory mechanics, gas exchange, hemodynamics, wet-to-dry ratios, and histology were similar in the two groups, the decrease of end-expiratory lung impedance was significantly greater in the control group (P = 0.02). We conclude that with our experimental conditions, the reduction of energy dissipated in the respiratory system did not lead to appreciable differences in VILI.NEW & NOTEWORTHY Energy dissipation within the respiratory system is a factor promoting ventilator-induced lung injury (VILI). In this animal study, we modulated the expiratory flow, reducing the energy dissipated in the system. However, this reduction happened mostly across the endotracheal tube, and only partly in the respiratory system. Therefore, in healthy lungs, the advantage in energy dissipation does not reduce VILI, but the advantages might be more relevant in diseased lungs under injurious ventilation.

Dysregulation of the Scribble/YAP/ß-catenin axis sustains the fibroinflammatory response in a PKHD1-/- mouse model of congenital hepatic fibrosis.

Congenital hepatic fibrosis (CHF), a genetic cholangiopathy characterized by fibropolycystic changes in the biliary tree, is caused by mutations in the PKHD1 gene, leading to defective fibrocystin (FPC), changes in planar cell polarity (PCP) and increased ß-catenin-dependent chemokine secretion. In this study, we aimed at understanding the role of Scribble (a protein involved in PCP), Yes-associated protein (YAP), and ß-catenin in the regulation of the fibroinflammatory phenotype of FPC-defective cholangiocytes. Immunohistochemistry showed that compared with wild type (WT) mice, in FPC-defective (Pkhd1del4/del4 ) mice nuclear expression of YAP/TAZ in cystic cholangiocytes, significantly increased and correlated with connective tissue growth factor (CTGF) expression and pericystic fibrosis, while Scribble expression on biliary cyst cells was markedly decreased. Cholangiocytes isolated from WT mice showed intense Scribble immunoreactivity at the membrane, but minimal nuclear expression of YAP, which conversely increased, together with CTGF, after small interfering RNA (siRNA) silencing of Scribble. In FPC-defective cholangiocytes, inhibition of YAP nuclear import reduced ß-catenin nuclear expression, and CTGF, integrin ß6, CXCL1, and CXCL10 mRNA levels, whereas inhibition of ß-catenin signaling did not affect nuclear translocation of YAP. Notably, siRNA silencing of Scribble and YAP in WT cholangiocytes mimics the fibroinflammatory changes of FPC-defective cholangiocytes. Conditional deletion of ß-catenin in Pkhd1del4/del4  mice reduced cyst growth, inflammation and fibrosis, without affecting YAP nuclear expression. In conclusion, the defective anchor of Scribble to the membrane facilitates the nuclear translocation of YAP and ß-catenin with gain of a fibroinflammatory phenotype. The Scribble/YAP/ß-catenin axis is a critical factor in the sequence of events linking the genetic defect to fibrocystic trait of cholangiocytes in CHF.

Acute Neurological Involvement after Donor Lymphocyte Infusion for Post-Transplant Viral Infection: The Same Pattern of Novel Cancer Immunotherapy-Related CNS Toxicity?

Early post-transplant is the critical phase for the success of hematopoietic stem cell transplantation (HSCT). New viral infections and the reactivations associated with complete ablation of the recipient's T-cell immunity and inefficient reconstitution of the donor-derived system represent the main risks of HSCT. To date, the pharmacological treatments for post-HSCT viral infection-related complications have many limitations. Adoptive cell therapy (ACT) represents a new pharmacological strategy, allowing us to reconstitute the immune response to infectious agents in the post-HSC period. To demonstrate the potential advantage of this novel immunotherapy strategy, we report three cases of pediatric patients and the respective central nervous system complications after donor lymphocyte infusion.

Pathological characteristics of liver sinusoidal thrombosis in COVID-19 patients: A series of 43 cases.

AIM: Coronavirus disease (COVID-19) is characterized by pneumonia with secondary damage to multiple organs including the liver. Liver injury (elevated alanine aminotransferase [ALT] and aspartate aminotransferase [AST]) often correlates with disease severity in COVID-19 patients. The aim of this study is to identify pathological microthrombi in COVID-19 patient livers by correlating their morphology with liver injury, and examine hyperfibrinogenemia and von Willebrand factor (vWF) as mechanisms of their formation. METHODS: Forty-three post-mortem liver biopsy samples from COVID-19 patients were obtained from Papa Giovanni XXIII Hospital in Bergamo, Italy. Three morphological features of microthrombosis (sinusoidal erythrocyte aggregation [SEA], platelet microthrombi [PMT], and fibrous thrombi) were evaluated. RESULTS: We found liver sinusoidal microthrombosis in 23 COVID-19 patients (53%) was associated with a higher serum ALT and AST level compared to those without (ALT: 10-fold, p = 0.04; AST: 11-fold, p = 0.08). Of 43 livers, PMT and SEA were observed in 14 (33%) and 19 (44%) cases, respectively. Fibrous thrombi were not observed. Platelet microthrombi were associated with increased ALT (p < 0.01), whereas SEA was not (p = 0.73). In COVID-19 livers, strong vWF staining in liver sinusoidal endothelial cells was associated with significantly increased platelet adhesion (1.7-fold, p = 0.0016), compared to those with weak sinusoidal vWF (2-fold, p < 0.0001). Sinusoidal erythrocyte aggregation in 19 (83%) liver samples was mainly seen in zone 2. Livers with SEA had significantly higher fibrinogen (1.6-fold, p = 0.031) compared to those without SEA in COVID-19 patients. CONCLUSIONS: Liver PMT is a pathologically important thrombosis associated with liver injury in COVID-19, while SEA is a unique morphological feature of COVID-19 patient livers. Sinusoidal vWF and hyperfibrinogenemia could contribute to PMT and SEA formation.

Liver injury in COVID-19 and IL-6 trans-signaling-induced endotheliopathy.

BACKGROUND AND AIMS: COVID-19 is associated with liver injury and elevated interleukin-6 (IL-6). We hypothesized that IL-6 trans-signaling in liver sinusoidal endothelial cells (LSECs) leads to endotheliopathy (a proinflammatory and procoagulant state) and liver injury in COVID-19. METHODS: Coagulopathy, endotheliopathy, and alanine aminotransferase (ALT) were retrospectively analyzed in a subset (n = 68), followed by a larger cohort (n = 3,780) of patients with COVID-19. Liver histology from 43 patients with COVID-19 was analyzed for endotheliopathy and its relationship to liver injury. Primary human LSECs were used to establish the IL-6 trans-signaling mechanism. RESULTS: Factor VIII, fibrinogen, D-dimer, von Willebrand factor (vWF) activity/antigen (biomarkers of coagulopathy/endotheliopathy) were significantly elevated in patients with COVID-19 and liver injury (elevated ALT). IL-6 positively correlated with vWF antigen (p = 0.02), factor VIII activity (p = 0.02), and D-dimer (p <0.0001). On liver histology, patients with COVID-19 and elevated ALT had significantly increased vWF and platelet staining, supporting a link between liver injury, coagulopathy, and endotheliopathy. Intralobular neutrophils positively correlated with platelet (p <0.0001) and vWF (p <0.01) staining, and IL-6 levels positively correlated with vWF staining (p <0.01). IL-6 trans-signaling leads to increased expression of procoagulant (factor VIII, vWF) and proinflammatory factors, increased cell surface vWF (p <0.01), and increased platelet attachment in LSECs. These effects were blocked by soluble glycoprotein 130 (IL-6 trans-signaling inhibitor), the JAK inhibitor ruxolitinib, and STAT1/3 small-interfering RNA knockdown. Hepatocyte fibrinogen expression was increased by the supernatant of LSECs subjected to IL-6 trans-signaling. CONCLUSION: IL-6 trans-signaling drives the coagulopathy and hepatic endotheliopathy associated with COVID-19 and could be a possible mechanism behind liver injury in these patients. LAY SUMMARY: Patients with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection often have liver injury, but why this occurs remains unknown. High levels of interleukin-6 (IL-6) and its circulating receptor, which form a complex to induce inflammatory signals, have been observed in patients with COVID-19. This paper demonstrates that the IL-6 signaling complex causes harmful changes to liver sinusoidal endothelial cells and may promote blood clotting and contribute to liver injury.

Hepatic hemangioendothelioma of infancy: clinical features of a large cohort of patients and proposed management.

PURPOSE: The management of hepatic hemangioendothelioma (HHE) may be challenging. We aimed to review a large cohort of children who presented to our centers with symptomatic HHE in the last 16 years. METHODS: We collected age at presentation, clinical features, histology, diagnostic process, management and outcome. RESULTS: Twenty seven patients (male/female 5/22), median age 13 days (1-1530) presented with hepatomegaly (24/27), cardiac failure (10/27), cutaneous hemangiomas (8/27), fever and anemia (6/27 each), vomiting (5/27), splenomegaly (4/27). The lesion was focal, multifocal, or diffuse in 9 patients of each group. The management included medical treatment (8/27), embolization (8/27), resection (3/27), observation (6/27), transplantation (2/27). After 16 months' follow-up (30 days-11 years), 23/27 (85%) were alive. Diffuse lesions (4/4), cardiac failure (4/4), type II histology (4/4), age older than 6 months at diagnosis (3/4) predicted mortality (all p < 0.01). Histology showed type 1 lesion in 3/8, type 2 in 3/8, and type 3 in 2/8 with foci of angiosarcoma. CONCLUSION: Most patients with symptomatic HHE can be managed successfully with a combination of medical, radiological and surgical treatments. Patients with diffuse lesions, late presentation, cardiac failure and type II histology have a poor outcome. LEVEL OF EVIDENCE: Diagnostic level IV. Therapeutic level IV.

Use of oral vancomycin in children with autoimmune liver disease: A single centre experience.

BACKGROUND: Previous reports showed some beneficial effect of oral vancomycin treatment (OVT) in children with primary sclerosing cholangitis; conversely, the experience in patients with other autoimmune liver diseases (AILD), including autoimmune hepatitis (AIH) and autoimmune sclerosing cholangitis (ASC), is scant. AIM: To assess the response to immunosuppressive treatment (IS) and to OVT in children diagnosed with AILD. METHODS: Retrospective study of children diagnosed with AIH (normal biliary tree at cholangiography) and ASC (abnormal biliary tree at cholangiography) in the last 10 years. All underwent standard immunosuppressive therapy (IS), but non-responders received also OVT. Biochemical remission [normal aspartate aminotransferase (AST)] and immunological remission (normal IgG and negative autoantibodies) rates and Sclerosing Cholangitis Outcomes in Pediatrics (SCOPE) index were assessed and compared during the follow up. RESULTS: 75 children were included [69% female, median age 10.5 years (5.6-13.4 years), AIH = 54, ASC= 21]. Sixty-three patients (84%, AIH = 52, ASC = 11) were treated with standard IS and 61 achieved biochemical remission, whereas 12 not responding to IS [16%, F = 75%, median age 13.5 years, (12.2-15.7), 10 with ASC] required OVT and 8 achieved biochemical remission. Overall OVT increased the biochemical remission rate of the whole group of AILD patients from 81% (61/75) to 92% (69/75). Median values of AST, alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) decreased significantly after OVT start (P < 0.05). Complete normalization of livers enzymes (AST, ALT and GGT) was observed in 6/12 patients (50%). Decrease in SCOPE index score was reported in 5/12 patients (42%). At last follow up (median of 4.4 years, range 0.6-13.8 years) all 75 patients are alive, 6 (8%, 1 with ASC) successfully discontinued medications, 1 (with ASC) required liver transplantation. CONCLUSION: Children with AIH and ASC respond well to IS treatment. OVT may represent a valuable treatment option to achieve biochemical remission in patients not responding to standard IS. These promising preliminary results suggest that a prospective study is indicated to define the efficacy of OVT in AILD.

Subclinical biliary strictures as a cause of long-term allograft dysfunction in children who underwent liver transplantation.

We aimed to evaluate the role of liver biopsy to predict subclinical biliary strictures (BS) and assess the impact of BS on long-term allograft dysfunction following liver transplantation in children (LT). We reviewed all liver biopsies performed from 2012-2018. Percutaneous transhepatic cholangiography (PTC) was performed in patients presenting cholangiolar proliferation on cytokeratin-7 stained sections. We performed 271 biopsies in 161 children (86% with a left lateral segment); 44/161 (27%) presented with diffuse or multifocal cholangiolar proliferation. Among them, a tight BS was confirmed in 38/44 (86%, 24% of total) and it was managed by balloon dilatation. Cholangiolar proliferation showed a positive predictive value (PPV) for BS of 86.4%. Levels of alkaline phosphatase >325 IU/L predicted BS (P = .007). Dilatation of intrahepatic bile ducts on ultrasound was found only in 44% of patients with BS. Following a median follow-up of 9.2 years, only 15/38 (39%) patients resolved the BS. In conclusion subclinical BS is very common and probably underdiagnosed in these patients. Histological evidence of cholangiolar proliferation detectable by cytokeratin-7 immunostain should be preferred to liver function tests and ultrasound to suspect BS. BS in this setting should be regarded as a main cause of long-term allograft dysfunction.

Endothelial injury and thrombotic microangiopathy in COVID-19: Treatment with the lectin-pathway inhibitor narsoplimab.

In COVID-19, acute respiratory distress syndrome (ARDS) and thrombotic events are frequent, life-threatening complications. Autopsies commonly show arterial thrombosis and severe endothelial damage. Endothelial damage, which can play an early and central pathogenic role in ARDS and thrombosis, activates the lectin pathway of complement. Mannan-binding lectin-associated serine protease-2 (MASP-2), the lectin pathway's effector enzyme, binds the nucleocapsid protein of severe acute respiratory syndrome-associated coronavirus-2 (SARS-CoV-2), resulting in complement activation and lung injury. Narsoplimab, a fully human immunoglobulin gamma 4 (IgG4) monoclonal antibody against MASP-2, inhibits lectin pathway activation and has anticoagulant effects. In this study, the first time a lectin-pathway inhibitor was used to treat COVID-19, six COVID-19 patients with ARDS requiring continuous positive airway pressure (CPAP) or intubation received narsoplimab under compassionate use. At baseline and during treatment, circulating endothelial cell (CEC) counts and serum levels of interleukin-6 (IL-6), interleukin-8 (IL-8), C-reactive protein (CRP) and lactate dehydrogenase (LDH) were assessed. Narsoplimab treatment was associated with rapid and sustained reduction of CEC and concurrent reduction of serum IL-6, IL-8, CRP and LDH. Narsoplimab was well tolerated; no adverse drug reactions were reported. Two control groups were used for retrospective comparison, both showing significantly higher mortality than the narsoplimab-treated group. All narsoplimab-treated patients recovered and survived. Narsoplimab may be an effective treatment for COVID-19 by reducing COVID-19-related endothelial cell damage and the resultant inflammation and thrombotic risk.

Successful fenofibrate therapy for severe and persistent hypertriglyceridemia in a boy with cirrhosis and glycerol-3-phosphate dehydrogenase 1 deficiency.

Glycerol-3-phosphate dehydrogenase 1 deficiency is a rare autosomal recessive disorder caused by mutations in the GPD1 gene (GPD1; OMIM*138420). Very few cases are reported in literature. It usually manifests in early infancy with transient hypertriglyceridemia, hepatomegaly, steatosis, and fibrosis. We report the case of a 16-year-old boy followed since the age of 1 year for hepatomegaly, elevated liver enzymes, and persistent hypertriglyceridemia. Abdominal ultrasound showed diffuse liver echogenicity and liver biopsy disclosed cirrhosis with micro and macrovesicular steatosis. Next-generation sequencing for metabolic and genetic liver diseases was conducted with the identification of the homozygous mutation c.895G>A in GPD1 gene resulting in the aminocidic substitution p.G299R. Considering the persistent and progressive increase of plasma triglycerides, fenofibrate treatment was started at 15 years of age allowing triglyceride level reduction in the following 1-year follow-up.

Liver histopathology in severe COVID 19 respiratory failure is suggestive of vascular alterations.

SARS2-CoV-2 breakout in Italy caused a huge number of severely ill patients with a serious increase in mortality. Although lungs seem to be the main target of the infection, very few information are available about liver involvement, possibly evocating a systemic disease. Post-mortem wedge liver biopsies from 48 patients died from severe pulmonary COVID-19 disease with respiratory failure were collected from two main hospitals in northern Italy. No patient had clinical symptoms of liver disease or signs of liver failure before and during hospitalization; for each of them liver function tests were available. All liver samples showed minimal inflammation features. Histological pictures compatible with vascular alterations were observed, characterized by increase in number of portal vein branches associated with lumen massive dilatation, partial or complete luminal thrombosis of portal and sinusoidal vessels, fibrosis of portal tract, focally markedly enlarged and fibrotic. SARS-CoV-2 was found in 15 of 22 samples tested by in situ hybridization method. Our preliminary results confirm the clinical impression that liver failure is not a main concern and this organ is not the target of significant inflammatory damage. Histopathological findings are highly suggestive for marked derangement of intrahepatic blood vessel network secondary to systemic changes induced by virus that could target not only lung parenchyma but also cardiovascular system, coagulation cascade and endothelial layer of blood vessels. It still remains unclear if the mentioned changes are directly related to virus infection or if SARS-CoV-2 triggers a series of reactions leading to striking vascular alterations.

Pulmonary post-mortem findings in a series of COVID-19 cases from northern Italy: a two-centre descriptive study.

BACKGROUND: COVID-19 is characterised by respiratory symptoms, which deteriorate into respiratory failure in a substantial proportion of cases, requiring intensive care in up to a third of patients admitted to hospital. Analysis of the pathological features in the lung tissues of patients who have died with COVID-19 could help us to understand the disease pathogenesis and clinical outcomes. METHODS: We systematically analysed lung tissue samples from 38 patients who died from COVID-19 in two hospitals in northern Italy between Feb 29 and March 24, 2020. The most representative areas identified at macroscopic examination were selected, and tissue blocks (median seven, range five to nine) were taken from each lung and fixed in 10% buffered formalin for at least 48 h. Tissues were assessed with use of haematoxylin and eosin staining, immunohistochemical staining for inflammatory infiltrate and cellular components (including staining with antibodies against CD68, CD3, CD45, CD61, TTF1, p40, and Ki-67), and electron microscopy to identify virion localisation. FINDINGS: All cases showed features of the exudative and proliferative phases of diffuse alveolar damage, which included capillary congestion (in all cases), necrosis of pneumocytes (in all cases), hyaline membranes (in 33 cases), interstitial and intra-alveolar oedema (in 37 cases), type 2 pneumocyte hyperplasia (in all cases), squamous metaplasia with atypia (in 21 cases), and platelet-fibrin thrombi (in 33 cases). The inflammatory infiltrate, observed in all cases, was largely composed of macrophages in the alveolar lumina (in 24 cases) and lymphocytes in the interstitium (in 31 cases). Electron microscopy revealed that viral particles were predominantly located in the pneumocytes. INTERPRETATION: The predominant pattern of lung lesions in patients with COVID-19 patients is diffuse alveolar damage, as described in patients infected with severe acute respiratory syndrome and Middle East respiratory syndrome coronaviruses. Hyaline membrane formation and pneumocyte atypical hyperplasia are frequent. Importantly, the presence of platelet-fibrin thrombi in small arterial vessels is consistent with coagulopathy, which appears to be common in patients with COVID-19 and should be one of the main targets of therapy. FUNDING: None.

Treatment of hepatitis C in two paediatric patients using sofosbuvir during haematopoietic stem cell transplantation.

We report the first two paediatric cases of sofosbuvir treatment during high-intensity myeloablative conditioning and engraftment phases of haematopoietic stem cell transplantation. These reports highlight the safety of sofosbuvir during all phases of transplantation and the lack of interaction between sofosbuvir and alkylating or immunosuppressive agents.

What is known about deferasirox chelation therapy in pediatric HSCT recipients: two case reports of metabolic acidosis.

To date, in pediatric field, various hematological malignancies are increasingly treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Iron overload and systemic siderosis often occur in this particular cohort of patients and are associated with poor prognosis. We describe herein the case of two allo-HSCT patients, on treatment with deferasirox; they showed histopathological elements compatible with venoocclusive disease or vanishing bile duct syndrome in ductopenic evolution before deferasirox started. The first patient developed drug-induced liver damage with metabolic acidosis and the second one a liver impairment with Fanconi syndrome. After withdrawing deferasirox treatment, both patients showed improvement. Measurements of drug plasma concentrations were performed by HPLC assay. The reduction and consequent disappearance of symptoms after the suspension of deferasirox substantiate its role in inducing hepatic damage, probably enabling the diagnosis of drug-induced liver damage. But the difficulties in diagnosing drug-related toxicity must be underlined, especially in compromised subjects. For these reasons, in patients requiring iron-chelating therapy, close and careful drug therapeutic monitoring is strongly recommended.

Vanishing Bile Ducts in the Long Term after Pediatric Hematopoietic Stem Cell Transplantation.

There are no structured studies on liver histology after hematopoietic stem cell transplantation (HSCT). We aimed to prospectively describe the clinicopathologic features of liver disease in the long term after HSCT in an observational, longitudinal study of liver histology in a consecutive cohort of children undergoing allogeneic HSCT. First liver biopsy was performed in presence of abnormal liver function tests and repeated per protocol thereafter. A previously reported semiquantitative score evaluating inflammation, cholestasis, and ductopenia (bile ducts-to-portal tracts ratio ≤ .5) was adopted. Graft-versus-host disease (GVHD) was diagnosed according to standard criteria. We evaluated 131 biopsies taken in 50 HSCTs performed in 47 children (mean age, 9.7 ± 5.2 years). Pre-HSCT chemotherapy was administered in 36 of 50 (72%). GVHD was diagnosed in 17 of 50 (34%). Over time the overall score decreased from a mean of 6 ± 2.7 to 3.25 ± .96 (P < .01), inflammation from 1.22 ± 1.19 to 1 ± 0 (not significant), and cholestasis from 3.9 ± 2.08 to 1.5 ± .58 (P < .01). Ductopenia, found in 113 of 131 biopsies (93%), worsened from .63 ± .35 to .16 ± .14 (P < .01). On multivariate analysis severe ductopenia (ratio ≤ .2) was associated with previous chemotherapy (P = .04), in particular with thiotepa, but not with history of GVHD. Vanishing bile duct syndrome after HSCT may be due to drug-induced liver disease. Longer follow-up will reveal whether these patients are prone to late liver-related morbidity and mortality.

Total body irradiation and iron chelation treatment are associated with pancreatic injury following pediatric hematopoietic stem cell transplantation.

Whereas many studies have addressed the risk of organ dysfunction following hematopoietic stem cell transplantation (HSCT), little is known about pancreatic susceptibility in this setting. We aimed to investigate the effect of iron overload (IO) and total body irradiation (TBI) on pancreatic function of children undergoing HSCT. We retrospectively evaluated children admitted between 2012-2016 fulfilling the following criteria: normal pancreatic iron concentration (PIC), regular pancreatic function before HSCT, availability of abdominal magnetic resonance imaging with gradient-recalled-echo sequences and a full set of biochemical markers of IO and pancreatic function performed before HSCT and at discharge. We divided the patients according to the use of TBI or myeloablative chemotherapy (MCHT) in the conditioning regimen. All patients with severe IO or moderate IO with a high risk of engraftment delay or transplantation-related complications underwent chelation therapy with deferoxamine (DFO) from the first day of conditioning to discharge. 63 patients had a HSCT in the study period, 13 did not fulfill the inclusion criteria; 50 (25 in each group) are included in the analysis, and did not show differences at baseline evaluation. At follow up testing the TBI group showed a significantly higher PIC (107,8±100,3 µmol/g vs 28,4±37,9 in MCHT group, p<0,0001). In the TBI group the patients who had DFO treatment had higher PIC (223,2±48,8 µmol/g vs 55,7±10,5 without DFO treatment, p<0,0001), and all patients having PIC >100 µmol/g at follow up had DFO-based chelation therapy, versus 26% of those with lower PIC (p<0,0001). The number of patients presenting exocrine pancreatic dysfunctions one month after transplantation was significantly higher in the TBI group (48% vs 4%; p<0.0001). The mean pancreatic volume reduction was significantly greater in the TBI group (39,1% vs 0,9% in the MCHT group; p<0,05), and was significantly worse on those who received DFO therapy. Based on our data, we suggest that TBI is detrimental for pancreatic functions, and speculate that DFO may contribute to the rapid pancreatic IO observed in these patients.

α1-Antitrypsin Polymerizes in Alveolar Macrophages of Smokers With and Without α1-Antitrypsin Deficiency.

BACKGROUND: The deficiency of α1-antitrypsin (AAT) is secondary to misfolding and polymerization of the abnormal Z-AAT in liver cells and is associated with lung emphysema. Alveolar macrophages (AMs) produce AAT; however, it is not known whether Z-AAT can polymerize in AMs, further decreasing lung AAT and promoting lung inflammation. Our intention was to investigate whether AAT polymerizes in human AMs and to study the possible relation between polymerization and degree of lung inflammation. METHODS: Immunohistochemical analysis with 2C1 monoclonal antibody specific for polymerized AAT was performed in sections of the following: nine lungs from individuals with AAT deficiency (AATD) and severe COPD; 35 smokers with normal AAT levels, of whom 24 had severe COPD and 11 did not have COPD; and 13 nonsmokers. AMs positive for AAT polymers were counted and expressed as the percentage of total AMs in the lungs. RESULTS: AAT polymerization was detected in 27% (4%-67%) of AMs from individuals with AATD but also in AMs from smokers with normal AAT with (24% [0%-70%]) and without (24% [0%-60%]) COPD, but not in AMs from nonsmokers (0% [0%-1.5%]) (P < .0001). The percentage of AMs with polymerized AAT correlated with pack-years smoked (r = 0.53, P = .0001), FEV1/FVC (r = -0.41, P = .005), small airways disease (r = 0.44, P = .004), and number of CD8+ T cells and neutrophils in alveolar walls (r = 0.51, P = .002; r = 0.31, P = .05, respectively). CONCLUSIONS: Polymerization of AAT in alveolar macrophages occurs in the lungs of individuals with AATD but also in smokers with normal AAT levels with or without COPD. Our findings highlight the similarities in the pathophysiology of COPD in individuals with and without AATD, adding a potentially important step to the mechanism of COPD.

Celiac Disease Diagnosis Without Biopsy: Is a 10× ULN Antitransglutaminase Result Suitable for a Chemiluminescence Method?

OBJECTIVES: 2012 European Society of Pediatric Gastroenterology, Hepatology and Nutrition guidelines allow to establish a celiac disease diagnosis without duodenal biopsy in symptomatic pediatric patients with antitissue transglutaminase (anti-tTG) titers >10 times the upper limit of normal. For some years now, new chemiluminescence immunoassays have been made available: it is important to establish the clinical performance of anti-tTG and to determine the cut-off best suited to predict Marsh ≥2 to avoid gastrointestinal endoscopy not only in children, but also in the adult population. METHODS: A total of 2565 patients performed duodenal biopsy from July 2012 to September 2016; we selected all the patients who had undergone QUANTA Flash anti-tTG immunoglobulin A (IgA) within -3 months of duodenal biopsy and before the start of gluten-free diet. A total of 827 patients fulfilled the criteria for selection. RESULTS: Using a cut-off of 20 chemiluminescent unit (CU; area under the curve: 0.995), sensitivity, specificity, positive, and negative predictive value were 98.2%, 98.4%, 97.9%, and 98.6%, respectively. For the correlation with Marsh ≥2, in the pediatric population, positive predictive values (PPV) were 92.1%, 99%, and 100% at 200 CU (10×), 560 CU (28×), and 1000 CU (50×), respectively. In the adult population PPV was 94.2%, 98.2%, and 100% at 200 CU (10×), 350 CU (15×), and 400 CU (20×). CONCLUSIONS: Sensitivity, specificity, positive, and negative predictive value of QUANTA Flash h-tTG IgA were excellent. The cut-off providing an optimized PPV for histological lesions compatible for celiac disease (Marsh ≥2) for the QUANTA Flash h-tTG IgA is 350 CU (15×) in adult and 560 CU (28×) in children.