Pre-emptive treatment of hepatitis B infection by lamivudine in two Tunisian renal transplant recipients.

Infection with hepatitis B virus has a major implication for transplant recipients due to the risk of reactivation under immunosuppression, progression to chronic liver disease, development of liver cirrhosis and hepatocellular carcinoma. We report two cases of renal transplantation patients who were hepatitis B surface antigen positive before transplantation and were treated by Lamivudine.

Visceral leishmaniasis in a renal transplant recipient treated with allopurinol.

Leishmaniasis is an infection caused by a protozoan parasite belonging to the genus Leishmania and transmitted by the Phlebotomus sandfly. We report a case of visceral leishmaniasis in a 49-year-old male renal transplant recipient, a resident of the western part of Tunisia, which is an endemic zone for the disease. Just before and after the transplantation, the patient resided in Tunis, which is non-endemic for leishmaniasis. Visceral leishmaniasis occurred eight years after renal transplantation, and the clinical picture was characterized by fever and pancytopenia. Leishmaniae were detected by bone marrow aspiration. Pentavalent antimonal was used for 28 days and was substituted by allopurinol (20 mg/kg per day). One year after the infection, the patient remains totally asymptomatic. Our report suggests that visceral leishmaniasis may complicate the clinical course of organ transplantation and can be fatal, particularly when untreated. Relapses may occur after completion of the apparently effective treatment. Allopurinol could be a solution to avoid these relapses.

Cancers after renal transplantation: multicenter experience.

Renal transplant recipients are at higher risk of certain tumors such as lymphomas and skin cancers and than the general and dialysis populations. We retrospectively studied the prevalence of tumors in adult renal transplant recipients in four Tunisian centers of transplantation in Tunis, Monsatir and Sfax from January 1986 to January 2005. The study included 36 patients; 19 men and 17 women with a mean age of 34.6 years (range from 18-54 years). The mean time since dialysis to transplantation was 43 months (6-131months). Maintenance therapy was based on calcineurin inhibitors (CNI) in 86 % of cases, on antimetabolites and corticosteroids in 100 % of cases. Anti-thymoglobulin was administered in a mean course of 12.4 days in 78 % of the patients. Acute rejection occurred in 25 cases and was treated with polyclonal or monoclonal antibodies on 40 % of cases. Incidence of cancer among our population was 7 % and occurred after a mean period of 54 months of transplantation (range from 4-160 months). Eighty three percent of the tumors were solid, and the rest were in the skin. Kaposi sarcoma formed 41.6 % and non-Hodgkin or Hodgkin lymphoma 27.7 % of the solid tumors, while spinocellular carcinoma formed 83% and basocellular carcinoma 17% of the skin tumors. Switching CNI to sirolimus in 8.3% cases was associated with a favorable outcome. Mortality was the outcome in 33.3% of the patients with cancer, while partial or complete regression of cancers was observed in 55.5% cases after decreasing the doses of the immunosuppressive medications. We conclude that post renal transplant cancer is mainly characterized by the predominance of Kaposi sarcoma favored by solar exposure and rigorously induced and maintained immunosuppression. Careful follow-up may results in early intervention and decrease mortality.

Anti CD25 treatment of human dendritic cells modulates both their cytokine synthesis profiles and their capacity to activate allogeneic CD4 T cells: a potential tolerogenic effect.

Recently, attention has been focused on the role for dendritic cells (DCs) in the promotion of peripheral tolerance. It is currently believed that the maturation/activation state of DCs might be a control point for the induction of graft tolerance through modifications of the activation state of T cells. We have observed IL-2, and IL-2 receptor gene expression by reverse transcriptase-polymerase chain reaction (RT-PCR) in human DC lysates following bacterial stimulation. It has been demonstrated in the present study IL-2R alpha (CD25) expression on human DCs upon LPS activation. DCs differentiated from monocytes were exposed to anti CD25 during maturation, anti CD25 treatment affected the abilities of human DCs to induce CD4+ T cell proliferation in response to alloantigens, maintained endocytic capacity, Anti CD25 treated DCs produce low levels of IL-12 and IFN and high level of IL-10. All these characteristics suggest that DCs may be used in cellular therapy either to induce allograft tolerance (anti CD25 treated DCs) or to restore immunity against tumors (IL-2 treated DCs).

[Peripheral arterial disease: where are we in 2006?]. / Arteriopathie obliterante des membres inferieurs: ou en est-on en 2006?

The prevalence of obstructive arterial disease is between 3.5 and 12.1% in 60 aged populations. It's a current disease which has a pernicious influence in quality of life. Management of patients with peripheral arterial occlusive disease has to be planned in the context of natural history, epidemiology, and apparent risk factors that predict deterioration. The purpose of this review is to take stock of the consensus and the controversies about terminology, epidemiology, diagnosis and management of peripheral arterial occlusive disease.

[Chronic-contained ruptured aortic aneurysm: un unusual cause of back pain]. / Rupture chronique cloisonnée d'un anévrysme de l'aorte abdominale: une cause inhabituelle de dorsalgies.

Chronic contained rupture of abdominal aortic aneurysm is a rare event which can cause diagnostic difficulties. It can present as a chronic back pain and the delayed diagnosis and delayed surgical repair may compromise the final results. The outcome of urgent repair of a chronic contained leak is equivalent to that of elective aneurysm repair. We report a case of contained rupture of a small abdominal aortic aneurysm with delayed diagnosis, evaluated by computed tomography showing a beginning erosion of the lumbar vertebral body. The patient was operated on within 24 hours on admission with uneventful surgical outcome.

[The effect of cryopreservation on the structural and functional properties of human vascular allografts]. / Analyse morphologique et fonctionnelle des allogreffes vasculaires humaines: effets des cryoprotecteurs et de la technique de cryoconservation.

OBJECTIVES: To assess the effet of cryopreservation on the structural and functional properties of venous and arterial human allografts. MATERIALS AND METHODS: Segments of arteries and veins harvested from multiorgan donors were divided into 3 groups: fresh-control tested for 24 hours after harvesting, frozen directly at -80 degrees C and frozen gradually (progressive freezing technique) and preserved in liquid nitrogen at -196 degrees C degree. The 2 cryopreserved groups of segments were allowed in two different cryoprotectant solutions (M1 and M2) containing both dimethyl sulphoxide (10%), RPMI 1640 for the first and M 199 for the second. Rapid thawing was done at regular intervals over 4 months and the allografts were processed for biomechanical, ultrastructural, morphological and immunohistochemical analysis. RESULTS: Cell damage was less intense in the specimens conserved in M1 solution and by progressive freezing technique especially for smooth muscle cells and endothelial cells which remained preserved until 12 weeks. CONCLUSION: Cryopreservation in both the solutions employed induce changes in the morphology of arterial wall. Better results were obtained with RPMI 1640 associated with progressive freezing.