Browsing by Author "Kamar, Nassim"

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A Monocentric Observational Study of Darbepoetin Alfa in Anemic Hepatitis-C-Virus Transplant Patients Treated With Ribavirin
(Başkent Üniversitesi, 2008-12) Kamar, Nassim; Rostaing, Lionel; Esposito, Laure; Ribes, David; Guitard, Joëlle
Objectives: Darbepoetin alfa is used to treat renal anemia; however, little information is available concerning its use during the posttransplant period, especially in HCV-positive patients treated with ribavirin for active hepatitis C. Materials and Methods: This study investigated the efficacy and safety of using darbepoetin alfa in this population during a 6-month treatment period. All anemic patients were HCV/RNA-positive, treated with ribavirin, and had impaired renal function. Patients (n=7) who had not been treated previously with recombinant human erythropoietin (rHuEPO) were placed in “group no rHuEPO.” Patients previously with recombinant human erythropoietin (n=16; “group rHuEPO”) were switched to darbepoetin alfa according to the European summary of product characteristics. Results: Seventy-three percent of the patients were men. The mean creatinine clearance at baseline was 58.7 ± 21.5 mL/min. All patients received an immunosuppressive treatment. Although mean hemoglobin levels remained stable in group no rHuEPO and increased in group rHuEPO, the difference was not statistically significant. Also, the median darbepoetin-alfa–weighted dose in group no rHuEPO increased while it remained stable in group rHuEPO, as did the median daily dosage of ribavirin; however, these differences were not statistically significant. Creatinine levels and creatinine clearance levels remained stable throughout the study. No significant medical events related to the treatment were reported during the study. Conclusions: Darbepoetin alfa was found to be efficient and well tolerated in correcting renal anemia in transplant recipients treated with ribavirin for active hepatitis C.
Alteration of Direct and Indirect Effects of Cytomegalovirus
(Başkent Üniversitesi, 2007-12) Kamar, Nassim; Rostaing, Lionel; Mengelle, Catherine
For recipients of a solid organ transplant, cytomegalovirus infection causes many pathological conditions including direct and indirect effects, most notably owing to the potency of the immunosuppressive medications used. Effects attributed to cytomegalovirus infection include graft rejection, decreased graft and patient survival rates, predisposition to other opportunistic infections, virally mediated malignancies, and various injuries specific to the transplanted organs (eg, accelerated coronary atherosclerosis following heart transplant, bronchiolitis obliterans syndrome in lung transplants, and vanishing bile-duct syndrome in liver allografts). Other indirect effects include posttransplant lymphoproliferative disorders, posttransplant new onset diabetes, and recurrence of hepatitis C virus infection. Direct effects are related to viral burden, whereas indirect effects may be observed even in the presence of low levels of cytomegalovirus replication. Being a function of the interaction between the virus and the host’s immune and inflammatory responses, the underlying indirect effects of viral infection are not completely understood. Whereas it has been shown that cytomegalovirus prophylaxis can decrease the direct and indirect effects of the virus, recent data indicate that pre-emptive therapy has no long-term impact upon the indirect effects. Prevention of cytomegalovirus-related indirect effects might be achieved only with prophylaxis.
Effects of Intraoperative versus Postoperative Administration of Rabbit Antithymocyte Antibodies on 1-Year Renal Function in Renal Transplant Patie
(Başkent Üniversitesi, 2006-06) Kamar, Nassim; Esposito, Laure; Ribes, David; Tkaczuk, Jean; Cointault, Olivier; Lavayssiere, Laurence; Abbal, Michel; Durand, Dominique; Rostaing, Lionel
Objectives: The aim of our study was to prospectively assess 1-year allograft outcomes and the evolution of lymphocyte subsets in a group of renal transplant patients who had received intraoperative rabbit antithymocyte antibodies (RATG). Materials and Methods: We compared 1-year allograft transplant outcomes in renal transplant recipients who had received intraoperative RATG (group 1, n = 53) with the outcomes observed in patients in a historical control group who had received postoperative RATG (group 2, n = 49). RATG were given at the same dosage (1 mg/kg) during the first 3 days, and then the dosage was adapted according to CD2 count, until calcineurin inhibitors were started. Results: The overall dosage of RATG administered was significantly lower in group 1. At day 4, CD2, CD3, and CD19 T-cell subset counts were significantly higher in patients in group 1. From 3 months after transplantation, CD4/CD8 ratios were significantly lower in patients in group 1 because of a rapid regeneration of CD8 T cells. One-year total lymphocyte counts were significantly higher in patients in group 1. There were fewer severe infectious complications in patients in group 1. One-year renal function was better in patients in group 2. Donor age was the only independent factor associated with renal function at both 1 month and 1 year after transplantation. Conclusions: When RATG are infused intraoperatively, a lower total amount of RATG is required to prevent acute rejection as compared with postoperative RATG infusion. Consequently, fewer serious lymphopenia-associated complications are observed during the first year after transplantation
Impact of Mycophenolic Acid Dose Modifications on Renal Function After Kidney Transplantation
(Başkent Üniversitesi, 2006-12) Kamar, Nassim; Oufroukhi, Loubna; Sallusto, Federico; Cointault, Olivier; Lavayssière, Laurence; Mouzin, Marc; Guitard, Joelle; Durand, Dominique; Rostaing, Lionel
Objective: Mycophenolic acid dose modifications after renal transplantation seem to adversely affect renal allograft outcome. The aim of this retrospective study was to examine the effect of mycophenolic acid dose modifications on renal function 1 year after transplantation and to determine the factors predictive of those dose modifications within the first year after renal transplantation. Patients and Methods: All 130 patients at our institution who were treated de novo between January 2002 and April 2003 with either a mycophenolate mofetil-based or an enteric-coated mycophenolate sodium-based therapy and who had a functioning renal allograft 1 month after transplantation were included in this study. Results: Fifty-seven patients (43.8%) underwent a dose modification during the first year after transplantation. One, 3, 6, and 12 months after transplantation, renal function was significantly improved in the patients who did not receive a dose modification. A mycophenolic acid dose that 1 year after transplantation was less than the initial dose received just after transplantation was an independent factor associated with deteriorating renal function. Sirolimus immunosuppression, Cytomegalovirus infection, and pretransplant lymphocyte counts were independent factors associated with mycophenolic acid dose modifications within the first year after kidney transplantation. Conclusions: Modification of the mycophenolic acid dose may adversely affect renal function 1 year after transplantation.
Monitoring Human Cytomegalovirus (HCMV) in HCMV-Seropositive Orthotopic Liver-transplant Recipients by Means of Quantitative Real-time Polymerase Chain Reaction
(Başkent Üniversitesi, 2006-12) Mengelle, Catherine; Abravanel-Legrand, Florence; Kamar, Nassim; Alain, Sophie; Basse, Grégoire; Pillet, Adèle; Lavayssière, Laurence; Suc, Bertrand; Izopet, Jacques; Rostaing, Lionel
Objective: Human Cytomegalovirus can be reactivated after orthotopic liver transplantation in patients who are seropositive for cytomegalovirus. Whether those cytomegalovirus-seropositive patients require immediate posttransplant (anti)cytomegalovirus prophylactic therapy or preemptive treatment as opposed to deferred treatment remains controversial. The aims of our study were to evaluate the relevance of cytomegalovirus monitoring with quantitative real-time polymerase chain reaction in whole blood and to analyze the factors that determine the treatment of the first episode of cytomegalovirus infection with intravenous ganciclovir in seropositive liver-transplant patients. Patients and Methods: Forty-two cytomegalovirus-seropositive liver-transplant patients were assessed for cytomegalovirus DNAemia every 2 weeks until posttransplant day 90 and every 3 to 4 weeks until day 180. Biochemical and hematologic parameters were also prospectively monitored. Results: Cytomegalovirus DNAemia was detected at least once in 27 patients (64%). Treatment was initiated in 12 patients (group 1) but not in 15 others (group 2). Median HCMV viral loads of the first positive and the highest DNAemia were statistically higher in group 1 than in group 2 (P = 0.01). Univariate analysis of DNAemia showed that alkaline phosphatase levels were significantly higher in group 1 than in group 2 (P = .0011) and that hemoglobin levels were significantly lower in group 1 than in group 2 (P = .0443). The results of multivariate analysis showed that the only factor that predicted the treatment of the first episode of HCMV DNAemia was a level of alkaline phosphatase greater than 150 IU/L [odds ratio, 20; range, 1.97-203.32; P = .01]. Conclusions: A combination of criteria, including viral-load kinetics, clinical factors, alkaline phosphatase levels (in particular), and the patient’s immune condition, is required to efficiently monitor patients who are seropositive for cytomegalovirus after orthotopic liver transplantation.
Perihepatitis and Perinephric Abscess Due to Mycoplasma hominis in a Kidney Transplant Patient
(Başkent Üniversitesi, 2007-12) Camara, Boubou; Mouzin, Marc; Kamar, Nassim; Rostaing, Lionel; Durand, Dominique; Game, Xavier; Guitard, Joelle; Esposito, Laure; Ribes, David
Mycoplasma hominis has been incriminated in several genital and extragenital infections. Here, we report the first case of perihepatitis associated with a perinephric abscess in a woman who had received a kidney transplant. Four months after the transplant, the patient was admitted for perirenal allograft pain, fever, and elevated inflammatory parameters and liver enzyme levels. A renal ultrasonography found a collection of fluid. Results of blood and urine analyses were within normal limits. Fluid aspiration of the peritoneal cavity was performed, and the results of cultures for bacteria and fungi were negative. The patient was treated by surgical lavage of the peritoneal cavity. Her fever resolved 5 days later. Two months after surgical lavage of the peritoneal cavity, her liver enzyme levels returned to the normal range. Three months after surgical lavage, cultures of the perinephric fluid showed Mycoplasma hominis. We conclude that in patients who present with perinephric fluid suspected of being infected, bacteriologic analysis of the fluid (from surgical lavage of the peritoneal cavity) should be performed. Antibiotics active against intracellular bacteria should be administered.
Prevalence of Cryoglobulinemia and Autoimmune Markers in Liver Transplant Patients
(Başkent Üniversitesi, 2008-09) Garrouste, Cyril; Rostaing, Lionel; Blancher, Antoine; Durand, Dominique; Lavayssière, Laurence; Esposito, Laure; Boulestin, Anne; Kamar, Nassim
Objectives: To examine the prevalence of cryoglobulinemia and autoimmune markers in stable liver transplant recipients and to determine risk factors and clinical impact. Materials and Methods: Ninety-two liver transplant recipients were tested for cryoglobulinemia, hepatitis B and C, complement C3, complement C4, CH50, antinuclear antibodies, anticytoplasmic neutrophil antibodies, anticardiolipid antibodies, rheumatoid factors, and lymphocyte subpopulations. Liver, renal, and hematology tests were done. Immunosuppressive regimens were based on calcineurin inhibitors in 94.6% of the patients. Results: Cryoglobulinemia was present in 18 patients (19.5%) with characteristics of type II in 27.7%, type III in 61.3%, and indeterminate in 11%. Cryoglobulinemia was present in 55.5% of patients with positive hepatitis C virus serology compared with 35.86% of patients with negative hepatitis C virus serology (P = .06). Among those with hepatitis C virus markers, cryoglobulinemia was present in 30%. Anticytoplasmic neutrophil antibodies were positive in 23% of the patients with cryoglobulinemia, but in only 5.4% of the patients without cryoglobulinemia (P = .006). Albuminemia was significantly lower in patients with cryoglobulinemia (38 ± 4.2 g/L) than it was in patients without cryoglobulinemia (40.2 ± 3.4; P = .05). Cryoglobulinemia was symptomatic in 4 patients (22.2% of all patients). Independent factors associated with cryoglobulinemia were presence of anticytoplasmic neutrophil antibodies, more than 4 HLA incompatibilities, alanine aminotransferase level of 0.68 µkat/L or more, and an albuminemia level greater than 38 g/L. Conclusions: Cryoglobulinemia is frequent after liver transplant and is symptomatic in approximately 20% of all patients.
Renal Function and Histology in Kidney Transplant Patients Receiving Tacrolimus and Sirolimus or Mycophenolate Mofetil
(Başkent Üniversitesi, 2006-12) Kamar, Nassim; Van, Tuan Tran; Ribes, David; Modesto, Anne; Cointault, Olivier; Lavayssière, Laurence; Ader, Jean Louis; Durand, Dominique; Rostaing, Lionel
Objective: The aim of this study was to assess the effects of tacrolimus in combination with either sirolimus (n = 10) or mycophenolate mofetil (n = 7) on renal function and renal histopathologic factors 6 and 12 months after kidney transplantation. Materials and Methods: Renal function was assessed by the glomerular filtration rate (as measured by the inulin clearance rate) and by determining renal functional reserve. A renal allograft biopsy was performed at the time of transplantation and 6 and 12 months later. Results: Serum creatinine levels tended to be higher in the sirolimus group 12 months after transplantation. In contrast, inulin clearance and renal functional reserve were similar in both groups 6 and 12 months after transplantation. With respect to histopathologic findings, only mononuclear-cell interstitial inflammation was significantly higher in the sirolimus group than in the mycophenolate mofetil group 12 months after transplantation. However, the progression of tubular atrophy, interstitial fibrosis, and vascular fibrous intimal thickening within the first postoperative year was significantly greater in the sirolimus group. Conclusions: In the long term, the addition of sirolimus to treatment with tacrolimus in de novo renal transplant patients might more adversely affect renal allograft survival than might the addition of mycophenolate mofetil to tacrolimus therapy.
Syphilis-Related Hepatitis in a Liver Transplant Patient
(Başkent Üniversitesi, 2007-12) Camara, Boubou; Rostaing, Lionel; Suc, Bertrand; Danjoux, Marie; Bonafe, Jean-Louis; Kamar, Nassim
We herein describe a case of secondary syphilis hepatitis in a liver transplant patient. This homosexual man presented 15 years after an orthotopic liver transplant with nonsquamous papillomacular rash, mild cytolysis, and anicteric cholestasis. Laboratory tests showed syphilis seroconversion with a VDRL test titer of 1/256, a Treponema pallidum hemagglutination assay of 1/5120, and a positive immunoglobulin M fluorescent Treponemal antibody absorbance. A liver biopsy performed 13 months after the diagnosis showed low-grade hepatitis with a METAVIR score of A1F1; it also showed moderate, nonspecific portal inflammation consisting primarily of neutrophils, with no evidence of cholestasis. The patient was given benzathine-penicillin (2 400 000 IU) with a transient increase in prednisolone dosages. Cytolysis rapidly, and cholestasis progressively, disappeared. Results of an immunoglobulin M fluorescent Treponemal antibody absorbance test became negative, whereas the VDRL test and the Treponema pallidum hemagglutination assay titers decreased slightly over time
Unusual Presentation of Cytomegalovirus Infection in Patients After Organ Transplant
(Başkent Üniversitesi, 2009-03) Guilbeau-Frugier, Céline; Rostaing, Lionel; Tiple, Aurélien; Kamar, Nassim; Esposito, Laure; Mengelle, Catherine; Combelles, Sophie; Otal, Philippe
Objectives: Cytomegalovirus (CMV) infection has an enormous impact in solid-organ transplant patients. In immunocompromised patients, CMV is associated with well-known direct effects. We herein describe 3 unusual patterns occurring in the setting of tissue-invasive CMV associated with high viral load. Materials and Methods: Of our 3 cases, the first patient after kidney transplant presented with cholestasis related to radiological cholangitis; the second patient after heart transplant presented with erythema nodosum with CMV infection as the sole cause; and the third patient after kidney transplant presented with acute renal failure related to mild interstitial nephritis with acute tubular necrosis and tubulitis. Results: The first patient’s cholestasis resolved with antiviral therapy, as did the erythema nodosum and CMV infection of the heart transplant patient. The third patient’s acute renal failure resolved by increased steroid dosage, plasma exchanges, and ganciclovir therapy. Conclusions: These 3 unusual presentations of tissue-invasive CMV had favorable outcomes with antiviral therapy.
Vertigo After Renal Transplantation: A Sign of Paucisymptomatic Cryptococcal Meningitis
(Başkent Üniversitesi, 2006-12) Mehrenberger, Marion; Kamar, Nassim; Borde, Jean-Sébastien; Estève-Fraysse, Marie-Josée; Viguier, Alain; Recco, Paulette; Durand, Dominique; Rostaing, Lionel
We report what is to our knowledge the first case of severe isolated vertigo that developed after renal transplantation and was a manifestation of cryptococcal meningitis. Treatment with antifungal therapy resulted in the complete resolution of vertiginous symptoms. Immunosuppressed patients with an opportunistic infection of the central nervous system can present with extremely tenuous features of infection and atypical neurologic signs.