The usefulness of immunohistochemical staining of bile tracts in biliary atresia.

AIM OF THE STUDY: To assess ductular proliferation (DP) and ductal plate malformation (DPM) in biliary atresia (BA) by means of immunohistochemical staining using cytokeratins CK7 and CK19 and neural cell adhesion molecule (NCAM) antibody CD56. MATERIAL AND METHODS: In 10 cases of BA, liver surgical biopsies obtained at the time of hepatoportoenterostomy were stained with H&E, PAS, Gomori and Azan methods. Immunohistochemical technique was used to outline bile ducts, ductular reaction, reactive bile duct/ductules and DPM by CK7, CK19 and NCAM antibody CD56. RESULTS: We found fibrosis, bile stasis and mild inflammation in all cases. In the routine staining DP was not seen in 3 cases. The immunohistochemical staining by means of CK19 was helpful in the detection of DP, and allowed it to be demonstrated in all cases. The biliary epithelial cell markers for CD56, CK7, CK19 were used for demonstration of bile duct cell but not hepatocyte alterations in the structure of intrahepatic biliary ducts and different stages of maturation. CD56 as a marker of immature bile ducts was expressed on biliary epithelium of bile ducts and bizarre forms of DPM in 6 cases. The positive expression of CD56 corresponded to the co-localization of CK19 of DPM, but not CK7, to the ductular reaction at the limiting plate of portal tracts. CD7, considered as a marker of DP, also stained ductal hepatocytes and multipotential oval cells, and was a marker of DPM in 3 cases. CONCLUSIONS: Use of CK7, CK19 and CD56 is helpful in BA diagnosis and allows differentiation of the stage of developing bile duct cells according to the expression pattern.

Changing treatment and outcome of children with hepatoblastoma: analysis of a single center experience over the last 20 years.

BACKGROUND/PURPOSE: The aim of the study was to analyze changing management and survival of children with hepatoblastoma (HBL) treated in one center. MATERIALS AND METHODS: Over the last 20 years, 51 children with HBL were treated. Surgery was performed in 48 children (94.1%), conventional liver resection in 38 (of those, 2 received a rescue liver transplantation [LTx] for relapse), and total hepatectomy and primary LTx in 10 patients. The remaining 3 patients received only palliative treatment. Patient data were analyzed for survival with respect to PRETreatment EXTent of disease (PRETEXT), metastases, histopathology, conventional resection, and LTx. RESULTS: Survival of children with HBL treated with liver resection is 71% and 80% for primary LTx. Favorable prognostic factors for patient survival was tumor histology as epithelial-fetal subtype and mixed epithelial and mesenchymal type, without teratoid features, and good response to chemotherapy (necrosis, fibrosis). Unfavorable prognostic factors were small cells undifferentiated, transitional liver cell tumor, α-fetoprotein level above 1,000,000 IU/mL and below 100 IU/mL at diagnosis, lung metastases, and local recurrence after initial resection. Survival was related to PRETEXT stage. However, among patients with PRETEXT III and IV, LTx resulted in better survival. CONCLUSION: Liver transplantation is a good option for children with advanced HBL. Early referral of children with potentially unresectable tumors to centers where combined treatment (chemotherapy, surgery including LTx) is available is crucial.

Amoxicillin/clavulanic acid-induced cholestatic liver injury after pediatric liver transplantation.

BACKGROUND: Amoxicillin/clavulanic acid-induced liver injury is a well recognized complication. Presentation and outcome may vary, which is related to individual liver maturity, genetic predisposition, enzyme heterogeneity, intensity of treatment, and drug interactions. In most cases withdrawing the drug is sufficient treatment; however, cases of progressive liver damage leading to liver transplantation have been reported. CASE REPORT: We present the case of an 8-year-old patient after liver transplantation who developed drug induced liver injury (DILI) after amoxicillin/clavulanic acid treatment for upper respiratory tract infection. Jaundice appeared 2 days after cessation of treatment. Clinical presentation and liver biopsy were consistent with DILI. Because of rapidly increasing bilirubin levels, we used 3 boluses of methylprednisolone and ursodeoxycholic acid. The treatment reversed progression of the cholestasis and full recovery was achieved in 3 months. CONCLUSIONS: In most cases of DILI, withdrawing the toxic drug is sufficient treatment, but we must be aware of a possible fatal outcome in case of progressive cholestasis. Corticosteroids may have beneficial effects in these patients.

Successful sirolimus rescue in tacrolimus-induced thrombotic microangiopathy after living-related liver transplantation.

TMA is a rare complication of tacrolimus. Disruption of endothelial cells, platelet aggregation, and intravascular mechanical fragmentation of red cells are core mechanisms of injury; however, exact pathways of toxicity are not clear. The clinical presentation may vary but TMA is a potentially life-threatening condition usually demanding aggressive treatment. We present the case of TMA in a child after living-related liver transplantation (LRLTx) on tacrolimus-based immunosuppressive regiment successfully converted to sirolimus.

HLA-B35 upregulates endothelin-1 and downregulates endothelial nitric oxide synthase via endoplasmic reticulum stress response in endothelial cells.

The presence of the HLA-B35 allele has emerged as an important risk factor for the development of isolated pulmonary hypertension in patients with scleroderma, however the mechanisms underlying this association have not been fully elucidated. The goal of our study was to determine the molecular mechanisms that mediate the biological effects of HLA-B35 in endothelial cells (ECs). Our data demonstrate that HLA-B35 expression at physiological levels via adenoviral vector resulted in significantly increased endothelin-1 (ET-1) and a significantly decreased endothelial NO synthase (eNOS), mRNA, and protein levels. Furthermore, HLA-B35 greatly upregulated expression of chaperones, including heat shock proteins (HSPs) HSP70 (HSPA1A and HSPA1B) and HSP40 (DNAJB1 and DNAJB9), suggesting that HLA-B35 induces the endoplasmic reticulum (ER) stress and unfolded protein response in ECs. Examination of selected mediators of the unfolded protein response, including H chain binding protein (BiP; GRP78), C/Ebp homologous protein (CHOP; GADD153), endoplasmic reticulum oxidase, and protein disulfide isomerase has revealed a consistent increase of BiP expression levels. Accordingly, thapsigargin, a known ER stress inducer, stimulated ET-1 mRNA and protein levels in ECs. This study suggests that HLA-B35 could contribute to EC dysfunction via ER stress-mediated induction of ET-1 in patients with pulmonary hypertension.

Reversal of tacrolimus-related hypertrophic cardiomyopathy after conversion to rapamycin in a pediatric liver transplant recipient.

Tacrolimus (Tac)-related hypertrophic cardiomyopathy (HCM) has been reported to be an unusual but serious complication affecting pediatric patients after solid organ transplantation. Herein, we present a case of young liver transplant recipient with Tac-induced HCM, treated by discontinuation of Tac followed by conversion to rapamycin (Rap). Our case report points out the potential but rather low risk of HCM during Tac immunosuppression in pediatric liver transplants and demonstrates that replacement of calcineurin inhibitors with mammalian target of Rap (mTOR) inhibitors may be an efficacious therapeutic tool to effect regression of established cardiac hypertrophy.

Recombinant activated factor VII in an unselected series of cases with upper gastrointestinal bleeding.

INTRODUCTION: The mortality rate associated with UGI bleeding remains high at 7-14%. Pharmacologic and endoscopic interventions are the current standard treatment, but there are few alternative options should these fail. This study aimed to assess the efficacy and safety of recombinant activated factor VII (rFVIIa) in the rescue treatment of severe upper gastrointestinal (UGI) bleeding. METHOD: Eleven patients (age: 8-64 years) were treated with rFVIIa at 15.0-90 microg/kg to control UGI bleeds. All three pediatric/adolescent cases and four of the eight adults had UGI hemorrhage associated with liver disease; the origins of the bleeds for remaining adults were trauma (n=1), peptic duodenal ulcer (n=1), hemorrhagic gastritis with sepsis (n=1) and pancreatitis (n=1). RESULTS: Bleeding stopped in seven patients and was markedly reduced in two patients, while there was no change in two patients. Coagulation parameters displayed a tendency to improve, and transfusion requirements were reduced in most patients. In total, five patients died within 2 weeks of rFVIIa treatment. In each case, fatality was judged unrelated to rFVIIa treatment. No thromboembolic events occurred. CONCLUSIONS: These results suggest that, even if our data are optimistic, the use of rFVIIa in the treatment of severe UGI bleeding warrants further investigation in prospective, randomized trials.

Single pretransplant bolus of recombinant activated factor VII ameliorates influence of risk factors for blood loss during orthotopic liver transplantation.

Large blood loss and transfusions during liver transplantation (LTx) may lead to serious complications and have a negative impact on post-transplant mortality and morbidity. In the retrospective study we compared two groups of recipients of primary cadaveric liver transplantation: group I (study group), consisted of 28 patients with preoperative risk of high intraoperative blood loss, including severe uncorrected coagulopathy. This group was given a bolus of recombinant activated factor VII (rFVIIa) just before LTx. Group II (control group) included 61 patients without a particular risk for increased intraoperative blood loss. These patients were not given rFVIIa. We analyzed both groups for: coagulation parameters before, during and after surgery (INR, APTT, factor VII activity), blood and FFP transfusions, operative time, postoperative complications (vascular thrombosis, reoperation for bleeding), postoperative ICU stay, post-transplant hospitalization time and mortality. Patients from the study group (I) had significantly worse coagulation parameters than patients in the control group (II) at the start of the surgical procedure; however, after administration of a bolus of rFVIIa there was immediate correction of coagulation in all recipients. No significant differences in intraoperative blood transfusions were observed between study and control groups (1980 +/- 311.4 mL vs. 1527 +/- 154.2 mL, respectively), operating time (8.7 h vs. 8.9 h) or ICU and hospital stay (7.03 days vs. 6.15 days and 40.89 days vs. 41.1 days). Re-exploration because of bleeding was performed in three patients from group I (10.7%) and in seven patients (11.5%) from group II. No single case of vascular thrombosis was observed in the study group, while in the control group there were three hepatic artery thromboses, two portal vein thromboses and one hepatic vein thrombosis. We conclude that rFVIIa given preoperatively to liver transplant recipients with several risk factors for high intraoperative bleeding adjusts these patients to a normal risk group, without an increased risk for thrombotic complications.

TGF-beta and CTGF have overlapping and distinct fibrogenic effects on human renal cells.

Transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) are ubiquitously expressed in various forms of tissue fibrosis, including fibrotic diseases of the kidney. To clarify the common and divergent roles of these growth factors in the cells responsible for pathological extracellular matrix (ECM) deposition in renal fibrosis, the effects of TGF-beta and CTGF on ECM expression in primary human mesangial (HMCs) and human proximal tubule epithelial cells (HTECs) were studied. Both TGF-beta and CTGF significantly induced collagen protein expression with similar potency in HMCs. Additionally, alpha(2)(I)-collagen promoter activity and mRNA levels were similarly induced by TGF-beta and CTGF in HMCs. However, only TGF-beta stimulated collagenous protein synthesis in HTECs. HTEC expression of tenascin-C (TN-C) was increased by TGF-beta and CTGF, although TGF-beta was the more potent inducer. Thus both growth factors elicit similar profibrogenic effects on ECM production in HMCs, while promoting divergent effects in HTECs. CTGF induction of TN-C, a marker of epithelial-mesenchymal transdifferentiation (EMT), with no significant induction of collagenous protein synthesis in HTECs, may suggest a more predominant role for CTGF in EMT rather than induction of excessive collagen deposition by HTECs during renal fibrosis.