No abstract

Passive immunization with hepatitis B surface antibody (anti-HBs) is important to prevent hepatitis B virus (HBV) recurrence after orthotopic liver transplantation for chronic HBV cirrhosis. Hepatitis B immune globulin (HBIG) dosing regimens have been poorly defined, utilize numerous routes of administration, and result in a high rate of HBV relapse and mortality. Twenty-five of 27 (93%) patients transplanted (four retransplants) for chronic HBV cirrhosis show no evidence of recurrent HBV (range, 2-55 months). Anti-HBs titers necessary to minimize the risk of hepatitis B surface antigen detectability were >500 IU/L for days 0 to 7, >250 IU/L for days 8 to 90, and >100 IU/L thereafter. Pretransplant HBV E antigen (HBeAG)-positive patients required more HBIG to achieve these goals than HBeAG-negative individuals. The elimination of anti-HBs changed continually for the initial 3 posttransplant months. The anti-HBs half-life increased from 0.7 days to 14.1 days. Anti-HBs elimination was significantly different in HBeAG+ and HBeAG- patients for the first week, but was subsequently indistinguishable after week 1. After 3 months, the half-life was statistically less for HBeAG+ patients, but the difference did not influence the clinical treatment regimens. Quantitative hepatitis B DNA levels did not predict the amount of HBIG required. HBV recurrence after orthotopic liver transplantation can be reduced by aggressive passive immunization. Pharmacokinetic analysis of anti-Hbs elimination can improve immunoglobulin therapy and prevent recurrence of clinical hepatitis.

Key Points Developed a targeted sequencing platform covering 63 genes linked to heritable bleeding, thrombotic, and platelet disorders. The ThromboGenomics platform provides a sensitive genetic test to obtain molecular diagnoses in patients with a suspected etiology.

Corneal avascularity is necessary for the preservation of optimal vision. The cornea maintains a dynamic balance between pro- and antiangiogenic factors that allows it to remain avascular under normal homeostatic conditions; however, corneal avascularity can be compromised by pathologic conditions that negate the cornea’s “angiogenic privilege.” The clinical relevance of corneal neovascularization has long been recognized, but management of this condition has been hindered by a lack of safe and effective therapeutic modalities. Herein, the etiology, epidemiology, pathogenesis, and treatment of corneal neovascularization are reviewed. Additionally, the authors’ recent findings regarding the clinical utility of topical ranibizumab (Lucentis®) and bevacizumab (Avastin®) in the treatment of corneal neovascularization are summarized. These findings clearly indicate that ranibizumab and bevacizumab are safe and effective treatments for corneal neovascularization when appropriate precautions are observed. Although direct comparisons are not conclusive, the results suggest that ranibizumab may be modestly superior to bevacizumab in terms of both onset of action and degree of efficacy. In order to justify the increased cost of ranibizumab, it will be necessary to demonstrate meaningful treatment superiority in a prospective, randomized, head-to-head comparison study.

Hepatitis C viral recurrence after orthotopic liver transplantation is almost universal. Hepatitis C induced graft failure may occur, but the clinical and histologic profiles are not well defined. The aim of this study was to describe the pattern of early graft failure in patients with recurrent hepatitis C after liver transplantation. Thirty patients with hepatitis C underwent liver transplantation from October 1989 through September 1994. Four patients were excluded because of death (2 patients), graft failure unrelated to hepatitis C (1 patient), and lost to follow-up (1 patient). Hepatitis C recurred in 24 of the 26 remaining patients. In 4 patients with hepatitis C virus recurrence and cholestasis, graft failure developed at 5.25, 11.0, 11.0, and 18.5 months. The medical records and liver biopsies were reviewed. In all 4 patients, a histologic pattern characterized by centrilobular ballooning degeneration developed and progressed to involve more than two-thirds of the lobules. Moderate to severe cholestasis and bridging fibrosis were present in all grafts at explant. Two patients had portal inflammation on 3-month biopsies consistent with viral hepatitis. All patients had mild macrovesicular steatosis, but only 1 patient had significant lymphoid aggregates. No patient had evidence of hepatic artery thrombosis. One patient had potential drug-induced cholestasis. One patient had 3 episodes of rejection that were not believed to contribute to graft loss. All 4 patients developed clinical features of hepatic failure and were retransplanted. Two patients had early recurrence of graft failure. We conclude that a pattern of progressive centrilobular ballooning degeneration, bridging fibrosis, and cholestasis occurs in some patients with hepatitis with early graft failure, similar to fibrosing cholestatic hepatitis seen in some transplant patients with recurrent hepatitis B.

No abstract

Ten patients with primary malignant tumors of the biliary tract, duodenum, or stomach and with secondary involvement of the liver underwent removal of most or all of the stomach, liver, pancreas, spleen, duodenum, proximal jejunum, terminal ileum, and ascending and transverse colon. The void in the upper abdomen was filled with an organ cluster graft consisting of the liver, pancreas, duodenum, and variable segments of proximal jejunum. Eight of the ten patients are alive after 3 to 9 months, all with good liver and pancreas function, and most with satisfactory function of the gastrointestinal tract. One of the surviving patients was in the hospital for 4 months because of multiple enteric fistulas and infections; the other seven survivors were discharged after an average of 43 ± 17.61 (SD) days. Recurrent tumor has not been proved in any of the surviving recipients and is suspected in only one. The study of such cases should provide insight and guidelines applicable to other visceral transplantation procedures that may be attempted in the future.

CD4+CD25+Foxp3+ Regulatory T cells (Tregs) play a critical role in immune tolerance. The plasticity and functional adaptability of Tregs in an inflammatory microenvironment has been demonstrated in autoimmunity. Here, using a double transgenic mouse model that permits Foxp3 lineage tracing, we investigated the phenotypic plasticity of Foxp3+ Tregs in a well-characterized murine model of corneal transplantation. In order to subvert the normal immune privilege of the cornea and foster an inflammatory milieu, host mice were exposed to desiccating stress prior to transplantation. Treg frequencies and function were decreased following desiccating stress, and this corresponded to decreased graft survival. A fraction of Tregs converted to IL-17+ or IFNγ+ ‘exFoxp3’ T cells that were phenotypically indistinguishable from effector Th17 or Th1 cells, respectively. We investigated how Foxp3 expression is modulated in different Treg subsets, demonstrating that neuropilin-1− peripherally-derived Tregs are particularly susceptible to conversion to IL-17+/IFNγ+ exFoxp3 cells in response to cues from their microenvironment. Finally, we show that IL-6 and IL-23 are implicated in the conversion of Tregs to exFoxp3 cells. This report demonstrates that the pathological conversion of Tregs contributes to the loss of corneal immune privilege.