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Chronic Immunosuppression (chronic + immunosuppression)
Selected AbstractsAngiosarcoma developing in a non-functioning arteriovenous fistula post-renal transplantJOURNAL OF SURGICAL ONCOLOGY, Issue 6 2010Yassar A. Qureshi MBBS Abstract Background Angiosarcomas comprise less than 1% of all sarcomas, arising from endothelial cells of blood or lymph vessels. Chronic immunosuppression increases the risk of many malignancies and an association between the development of angiosarcoma with an immunosuppressed state is established. A few cases have been reported of angiosarcomas arising in the post-renal transplant patient. Specifically, there have been six cases of an angiosarcoma arising in arteriovenous (AV) fistulae in this patient population. We describe a further case and review the relevant literature with specific emphasis on a possible mechanism for the development of angiosarcoma in the post-transplant patient. Case Presentation We report the case of a 48-year-old male who developed an angiosarcoma in a ligated native AV fistula. The lesion arose on the background of immunosuppression following a successful ABO-incompatible renal transplant for chronic renal failure. Conclusion Angiosarcomas are extremely rare tumours but should be considered as a differential diagnosis for an evolving mass near the site of an AV fistula. Diagnosis relies on an index of suspicion and obtaining a definitive histological diagnosis. Both clinicians and patients should be aware that an evolving mass within or around an AV fistula should prompt urgent biopsy. J. Surg. Oncol. 2010; 101:520,523. © 2010 Wiley-Liss, Inc. [source] Abnormal Pap smears in inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 8 2008Sunanda Kane MD Abstract Inflammatory bowel disease (IBD) is a chronic inflammatory condition that is frequently treated with immunomodulators. Previous work has demonstrated an increased risk for abnormal cervical cytology in women treated with chronic immunosuppression, due mainly to human papillomavirus. This review summarizes the data known for this relationship in women with IBD, and management strategies for patients found to have abnormal cervical cytology. (Inflamm Bowel Dis 2008) [source] The mechanisms underlying MMR deficiency in immunodeficiency-related non-Hodgkin lymphomas are different from those in other sporadic microsatellite instable neoplasmsINTERNATIONAL JOURNAL OF CANCER, Issue 10 2009Claire Borie Abstract The spectrum of tumors showing microsatellite instability (MSI) has recently been enlarged to sporadic neoplasms whose incidence is favored in the context of chronic immunosuppression. We investigated the biological, therapeutic and clinical features associated with MSI in immunodeficiency-related non-Hodgkin lymphomas (ID-RL). MSI screening was performed in 275 ID-RL. MSI ID-RL were further analyzed for MMR gene expression and for BRAF/KRAS mutations since these genes are frequently altered in MSI cancers. We also assessed the expression of O6 -methylguanine-DNA methyltransferase (MGMT), an enzyme whose inactivation has been reported in lymphomas and may help in the selection of MMR deficient clones. Unlike other sporadic MSI neoplasms, MSI ID-RL (N = 17) presented with heterogeneous MMR defects and no MLH1 promoter methylation. About one third of these tumors presented with normal expression of MLH1, MSH2, MSH6 and PMS2. They accumulated BRAF activating mutations (33%). Unlike other ID-RL, MSI ID-RL were primarily EBV-negative NHL of T-cell origin, and arose after long-term immunosuppression in patients who received azathioprine as part of their immunosuppressive regimen (p = 0.05) and/or who exhibited methylation-induced loss of expression of MGMT in tumor cells (p= 0.02). Overall, these results highlight that, in the context of deficient immune status, some MSI neoplasms arise through alternative mechanism when compared to other sporadic MSI neoplasms. They give the exact way how to make the diagnosis of MSI in these tumors and may help to define biological and clinicalrisk factors associated with their emergence in such a clinicalcontext. © 2009 UICC [source] New Devices for Chronic Ventricular SupportJOURNAL OF CARDIAC SURGERY, Issue 3 2001F.A.C.S., F.C.C.P., Kenneth L. Franco M.D. Congestive heart failure affects 5 million people in the United States with 500,000 new cases diagnosed each year. Medical and surgical therapy have helped many patients but when these options fail, heart transplantation remains the only other treatment available to help improve their condition. Heart transplantation suffers from the lack of a sufficient number of suitable donor organs, the complications of chronic immunosuppression, and many patients die while on the waiting list. A number of pulsatile and nonpulsatile cardiac assist devices are being developed to provide chronic support for patients with heart failure and to be an alternative to heart transplantation. It is estimated that as many as 60,000 patients with heart failure could be helped by mechanical devices used for chronic support. For these devices to be effective they must provide sufficient cardiac output to allow patients to perform their daily activities, have a low risk of thromboemboli, be fully implantable thereby reducing the risk of infection, and have a low incidence of device malfunction requiring part or all of the device to be replaced. In this article, we will review several new devices which have been developed over the past 5 years or so and will be in human clinical trials in the United States soon, either as a bridge or as an alternative to heart transplantation. [source] Detection of chimerism following vascularized bone allotransplantation by polymerase chain reaction using a Y-chromosome specific primerJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2003Keiichi Muramatsu Abstract Chimerism following allogeneic organ transplantation is a phenomenon known to occur and be associated with development of immunologic tolerance in allotransplantation. However, little is known about graft cell migration following vascularized bone allografting. In this study, chimerism was assessed following vascularized tibia transplantation from male DA or PVG donors to female PVG rat recipients using a semi-quantitative polymerase chain reaction for the Y-chromosome. FK-506 (Tacrolimus) was administered after transplantation for immunosuppression. All immunosuppresssed PVG rat recipients of PVG bone grafts showed a high level of chimerism (1%) in the thymus, spleen, liver and cervical lymph nodes at 18 weeks post-transplant. Donor cells were also detected in the contralateral tibia and humerus. In non-immunosuppressed PVG rat recipients of DA bone grafts, donor cells were detected in the spleen in three of five rats within 2 weeks post-transplant. In these animals the bone grafts were severely rejected. In immunosuppressed PVG rat recipients of DA bone grafts, two of five, four of eight and eight of 10 rats showed low level chimerism (0.1%) in peripheral blood at 1, 12, and 18 weeks post-transplant. Six rats showed a high level of chimerism in the spleen and thymus. Histological studies revealed no rejection findings through 18 weeks post-transplant. Our results indicate that chimerism, or the presence of graft cells in host tissue, may occur in the face of acute rejection and be demonstrable following vascularized isograft and allograft living bone transplantation when chronic immunosuppression is maintained. Graft vascular patency during the short-term likely allows cellular migration, even in the face of acute rejection. Long-term survival and proliferation of graft marrow elements in host tissue may be possible with adequate immunosuppression. © 2003 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Survival of ovarian allografts in an experimental animal modelPEDIATRIC TRANSPLANTATION, Issue 6 2007Roger G. Gosden Abstract: Transplantation of ovarian tissue is a promising strategy for fertility preservation in young cancer patients with premature ovarian failure if they have cryopreserved their own tissue before undergoing gonadotoxic treatment. However, extension of ovary donation to children and adults seeking treatment for hypogonadism is controversial unless the tissue does not provoke an immune reaction or specific tolerance can be safely and effectively achieved. The survival of heterotopic ovarian allografts was tested in a mouse model. Isografts were placed under the kidney capsule of ovariectomized animals differing at the H-2 haplotype (H-2d or H-2k). Within three wk, and in contrast to isografts, the allografts were rejected, although their survival was extended when donor and host strains shared the same haplotype (H-2k). Allograft survival was not improved if the tissue was implanted orthotopically. When monoclonal antibodies to CD4 antigens were administered at doses exceeding those effective for long-term tolerance to cardiac allografts, graft survival was prolonged in one of two strain combinations, but they failed to restore fertility. These results indicate that the ovary is not an immunologically privileged organ, as the older literature suggested, and chronic immunosuppression is likely to be required for ovarian allografts in clinical settings. [source] Disseminated Histoplasmosis Associated with Hemophagocytic Lymphohistiocytosis in Kidney Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2010M. M. Lo Transplant patients are susceptible to infectious complications due to chronic immunosuppression. We present two cases of persistent fever, weight loss and pancytopenia in kidney transplant recipients (originally concerning for posttransplant lymphoproliferative disease) that were later diagnosed with disseminated histoplasmosis on bone marrow and lymph node biopsy. In both patients, pancytopenia was due to hemophagocytic lymphohistiocytosis (HLH) which has rarely been described in association with histoplasmosis and not previously reported in kidney transplant recipients with this fungal infection. The diagnosis of histoplasmosis can be complex due to nonspecific symptomatology, delays in isolating histoplasma by fungal culture and false-negative antibody titers in immunocompromised patients. A review of the literature including the clinical features of histoplasmosis in immunosuppressed patients (prevalence, current diagnostic testing and treatment options) as well as the association of HLH in immunocompromised states are discussed. [source] Entrapment of dispersed pancreatic islet cells in CultiSpher-S macroporous gelatin microcarriers: Preparation, in vitro characterization, and microencapsulationBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2001S. Del Guerra Abstract Immunoprotection of pancreatic islets for successful allo- or xenotransplantation without chronic immunosuppression is an attractive, but still elusive, approach for curing type 1 diabetes. It was recently shown that, even in the absence of fibrotic overgrowth, other factors, mainly insufficient nutrition to the core of the islets, represent a major barrier for long-term survival of intraperitoneal microencapsulated islet grafts. The use of dispersed cells might contribute to solve this problem due to the conceivably easier nutritional support to the cells. In the present study, purified bovine islets, prepared by collagenase digestion and density gradient purification, and dispersed bovine islet cells, obtained by trypsin and DNAsi (viability > 90%), were entrapped into either 2% (w/v) sodium alginate (commonly used for encapsulation purposes) or (dispersed islet cells only) macroporous gelatin microcarriers (CulthiSpher-S, commonly used for the production of biologicals by animal cells). Insulin release studies in response to glucose were performed within 1 week and after 1 month from preparation of the varying systems and showed no capability of dispersed bovine islet cells within sodium alginate microcapsules to sense glucose concentration changes. On the contrary, bovine islet cells entrapped in CulthiSpher-S microcarriers showed maintained capacity of increasing insulin secretion upon enhanced glucose concentration challenge. In this case, insulin release was approximately 60% of that from intact bovine islets within sodium alginate microcapsules. MTT and hematoxylineosin staining of islet cell-containing microcarriers showed the presence of viable and metabolically active cells throughout the study period. This encouraging functional data prompted us to test whether the microcarriers could be immunoisolated for potential use in transplantation. The microcarriers were embedded within 3% sodium alginate, which was then covered with a poly-L-lysine layer and a final outer alginate layer. Maintained insulin secretion function of this system was observed, which raises the possibility of using microencapsulated CulthiSpher-S microcarriers, containing dispersed pancreatic islet cells, in experimental transplantation studies. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 741,744, 2001. [source] Cytomegaloviral retinitis from chronic immunosuppression following solid organ transplant surgeryCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 4 2010Navjit K Sanghera OD No abstract is available for this article. [source] | ||||||||||||||||||||||