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Featured researches published by Per Pfeffer.


Journal of The American Academy of Dermatology | 1999

Skin cancer in kidney and heart transplant recipients and different long-term immunosuppressive therapy regimens

Petter Jensen; Svein Hansen; Bjørn Møller; Torbjørn Leivestad; Per Pfeffer; Odd Geiran; Per Fauchald; Svein Simonsen

Abstract Background: Nonmelanoma skin cancer occurs frequently in organ transplant recipients, but the relative importance of different immunosuppressive therapy regimens is unclear. Objective: We studied the risk of skin cancer in the complete, single-center Norwegian cohort of kidney and heart transplant recipients (n = 2561). Methods: We determined cancer risk estimation by means of standardized incidence ratios and multivariate Cox regression. Results: Transplant recipients had an increased risk of cutaneous squamous cell carcinoma (SCC) (65-fold), malignant melanoma (3-fold), and Kaposis sarcoma (84-fold), and of lip SCC (20-fold), compared with the general population. After adjustment for age, kidney transplant recipients receiving cyclosporine, azathioprine, and prednisolone had a significantly (2.8 times) higher risk of cutaneous SCC relative to those receiving azathioprine and prednisolone. After adjustment for age and type of immunosuppressive regimen, heart transplant recipients had a significantly (2.9 times) higher risk than kidney transplant recipients. Conclusion: The risk of cutaneous SCC, malignant melanoma, Kaposis sarcoma, and lip SCC is increased in kidney and heart transplant recipients. The risk of posttransplant cutaneous SCC is related to the degree of immunosuppression caused by long-term immunosuppressive therapy. (J Am Acad Dermatol 1999;40:177-86.)


Kidney International | 2014

Long-term risks for kidney donors

Geir Mjøen; Stein Hallan; Anders Hartmann; Aksel Foss; Karsten Midtvedt; Ole Øyen; Anna Varberg Reisæter; Per Pfeffer; Trond Jenssen; Torbjørn Leivestad; Pål-Dag Line; Magnus Øvrehus; Dag Olav Dale; Hege Pihlstrøm; Ingar Holme; Friedo W. Dekker; Hallvard Holdaas

Previous studies have suggested that living kidney donors maintain long-term renal function and experience no increase in cardiovascular or all-cause mortality. However, most analyses have included control groups less healthy than the living donor population and have had relatively short follow-up periods. Here we compared long-term renal function and cardiovascular and all-cause mortality in living kidney donors compared with a control group of individuals who would have been eligible for donation. All-cause mortality, cardiovascular mortality, and end-stage renal disease (ESRD) was identified in 1901 individuals who donated a kidney during 1963 through 2007 with a median follow-up of 15.1 years. A control group of 32,621 potentially eligible kidney donors was selected, with a median follow-up of 24.9 years. Hazard ratio for all-cause death was significantly increased to 1.30 (95% confidence interval 1.11-1.52) for donors compared with controls. There was a significant corresponding increase in cardiovascular death to 1.40 (1.03-1.91), while the risk of ESRD was greatly and significantly increased to 11.38 (4.37-29.6). The overall incidence of ESRD among donors was 302 cases per million and might have been influenced by hereditary factors. Immunological renal disease was the cause of ESRD in the donors. Thus, kidney donors are at increased long-term risk for ESRD, cardiovascular, and all-cause mortality compared with a control group of non-donors who would have been eligible for donation.


Transplantation | 2003

Clinical outcomes during the first three months posttransplant in renal allograft recipients managed by C2 monitoring of cyclosporine microemulsion.

Eric Thervet; Per Pfeffer; Maria Piera Scolari; Lorenzo Toselli; Luis M. Pallard; Steven J. Chadban; Helen Pilmore; John Connolly; M. Buchler; Francesco Paolo Schena; Raymond Dandavino; Edward Cole

Background. MO2ART (monitoring of 2-hr absorption in renal transplantation) is the first prospective, multicenter trial of cyclosporine (CsA) blood level 2 hr postdose (C2) monitoring in de novo kidney recipients receiving CsA microemulsion (ME) (Neoral; Novartis, Basel, Switzerland). Efficacy and safety results from the first 3 months are presented here. Methods. MO2ART is a 12-month, open-label, randomized study involving 296 patients. In all patients, the dose of CsA-ME was adjusted to achieve protocol-defined C2 targets of 1.6 to 2.0 &mgr;g/mL for the first month, with subsequent tapering. Randomization into two target groups occurred at 3 months. All patients received steroids and mycophenolate mofetil (89%) or azathioprine. For patients with delayed graft function, the protocol permitted reduced C2 targets and prophylactic administration of antibodies. Results. At 3 months, overall incidence of biopsy-proven acute rejection was 11.5%. Median serum creatinine was 132 &mgr;mol/L. Patient and graft survival were 96.6% and 91.2%, respectively. C2 levels greater than 1.6 &mgr;g/mL were achieved within 5 days by 60.6% of patients with immediate graft function and 19.5% of patients with delayed graft function. Prophylactic antibodies were used in 15% of the total population. Twenty-four patients (8.1%) experienced serious adverse events with a suspected relation to CsA, and 26 patients (8.8%) discontinued the study because of adverse events (n=15) or after a switch in immunosuppression after rejection episodes (n=11). Conclusions. Patient management by C2 monitoring resulted in a low incidence of biopsy-proven acute rejection in standard risk de novo kidney recipients, 85% of whom did not receive prophylactic antibodies. CsA-ME with C2 monitoring provides excellent short-term efficacy and safety among de novo renal transplant patients.


Transplantation | 2008

Declining intracellular T-lymphocyte concentration of cyclosporine a precedes acute rejection in kidney transplant recipients.

Pål Falck; Anders Åsberg; Heidi Guldseth; Sara Bremer; Fatemeh Akhlaghi; Jan Leo Egge Reubsaet; Per Pfeffer; Anders Hartmann; Karsten Midtvedt

Background. We investigated cyclosporine A (CsA) concentrations at the site of action, inside T-lymphocytes, to evaluate its applicability as a new supplementary therapeutic drug monitoring method after renal transplantation. Method. In this prospective single-center study, 20 kidney transplant recipients, mean age 54 (range 21–74) years, on CsA-based immunosuppression were included within 2 weeks posttransplant and followed for 3 months. Nine patients also had one full 12-hour pharmacokinetic profile performed. T-lymphocytes were isolated from 7 ml whole blood using Prepacyte and intracellular CsA concentrations were determined using a validated liquid chromatography double mass spectrometry method. Results. Seven patients (35%) experienced acute rejections (all biopsy verified) during the first three months posttransplantation. Intracellular CsA concentrations tended to decline 1 week prior to acute rejection and the decrease was significant (−27.1±14.6%, P=0.014) three days before the rejection episodes were recognized clinically. In addition, the intracellular CsA area under the curve 0–12 measured during stable phase was 182% higher in the rejection-free patients (P=0.004). There was no difference between patients experiencing rejection and the rejection-free patients with respect to CsA C2-levels, dose (mg/kg), human leukocyte antigen mismatch, donor age, recipient age, or ABCB1 genotyping. Conclusion. Intracellular CsA T-lymphocyte concentrations declined significantly 3 days prior to a rejection episode and there was a general lower intracellular exposure of CsA in recipients experiencing rejection. Intracellular measurement of CsA therefore seems to have a potential to further improve individualization of therapeutic drug monitoring. Larger studies are needed to elucidate the role for intracellular T-lymphocyte measurements in ordinary clinical care, for both CsA and other immunosuppressive drugs.


American Journal of Transplantation | 2006

Calcineurin inhibitor-free immunosuppression in renal allograft recipients with thrombotic microangiopathy/hemolytic uremic syndrome

Ole Øyen; E. H. Strøm; Karsten Midtvedt; Ø. Bentdal; Anders Hartmann; Stein Bergan; Per Pfeffer; I. B. Brekke

Thrombotic microangiopathy (TMA) and hemolytic uremic syndrome (HUS) represent serious threats to kidney allograft recipients.


Transplantation | 1998

Unrelated living donors in 141 kidney transplantations: a one-center study.

Aksel Foss; Torbjørn Leivestad; Inge B. Brekke; Per Fauchald; Øystein Bentdal; Bjørn Lien; Per Pfeffer; Gunnar Sødal; Dagfinn Albrechtsen; Odd Søreide; Audun Flatmark

BACKGROUND Kidney transplantation is the optimal treatment for the majority of patients with end-stage renal disease. However, the shortage of kidneys for transplantation is a global problem, and any attempt to improve the donor situation would be of benefit to the growing number of patients on transplant waiting lists. PATIENTS AND METHODS Since 1984, we have transplanted 141 kidneys from genetically unrelated living donors. Donors were most often spouses and were accepted regardless of HLA match grade. Preemptive transplantation was performed in 39% of the patients. Standard triple-drug immunosuppression with prednisolone, cyclosporine, and azathioprine was used. The patients were followed from 6 months to 13 years. RESULTS The incidence of acute rejection during the first 3 months after transplantation was higher in recipients of grafts from unrelated donors than in recipients of grafts from related living donors or cadaveric donors. However, unrelated living donor grafts survived significantly better than did cadaveric grafts (P < 0.02) and had a survival rate similar to that of living-related donor grafts mismatched for one or both HLA haplotypes. The perioperative complication rate for the donor was low. CONCLUSION We consider unrelated living donors an excellent source for alleviating the shortage of donor kidneys.


Transplant International | 1993

Aortoiliac reconstruction in preparation for renal transplantation.

Inge B. Brekke; Bjørn Lien; Gunnar Sødal; A. Jakobsen; Øystein Bentdal; Per Pfeffer; Audun Flatmark; P. Fauchald

Aortoliac angiography has always been an integral part of the pretransplantation work-up of renal transplant candidates in Norway. The present study was undertaken to investigate the value of this routine. Based on the angiograms of approximately 1400 patients evaluated for renal transplantation during the 7-year period 1984–1991, 26 were found to have aortic and/or iliac atherosclerosis requiring pretransplant vascular reconstruction. Fifteen of the 26 patients had aneurysm of the abdominal aorta and 11 had extensive aortoiliac occlusive disease. A prosthetic graft was inserted in 25 patients and endarterectomy of the aortic bifurcation was performed in one. The cause of death was coronary heart disease in four of six patients who died before, and in one patient who died after, transplantation. Sixteen patients received a renal transplant while four patients are still on the waiting list. Fifteen of the recipients are alive, 14 with functioning renal transplants. The low yield of patients below 40 years of age requiring vascular reconstruction calls into question the routine use of angiographic investigation of renal transplant candidates below this age. However, we recommend this routine for the higher age groups because it often provides the surgeon performing the transplantation with valuable information. Aortoiliac reconstruction as preparation for renal transplantation is advocated when atherosclerosis of a degree that may preclude transplantation is found. Because of the high risk of myocardial infarction in these patients, one must be especially aware of coronary atherosclerosis when evaluating patients for this procedure.


Transplantation | 2003

C2 monitoring in maintenance renal transplant recipients: Is it worthwhile?

Karsten Midtvedt; Per Fauchald; Stein Bergan; Aud Høieggen; Stein Hallan; Einar Svarstad; Harald Bergrem; Bjoern O. Eriksen; Per Pfeffer; Ingvild Dalen; Torbjoern Leivestad

Presently, there is little knowledge regarding cyclosporine (CsA) concentration at 2 hr post-dose (C2) monitoring in maintenance patients. This study evaluates the actual C2 range in stable renal transplant recipients (who underwent transplantation >12 months ago). In addition, we investigated whether underexposure or overexposure to CsA (assessed by C2) affects graft function (as measured by serum [S]-creatinine). All renal transplant recipients in Norway receiving CsA were asked to participate; 1,447 fulfilled the criteria. Valid C2 and CsA trough concentration (C0) measurements were performed in 1,032 renal transplant recipients (71%) monitored by C0. Target C0 level was 75 to 125 &mgr;mol/L. CsA levels were measured using a Cloned Enzyme Donor Immunoassay method, and all analyses were performed in the same laboratory (overall mean [±standard deviation] CsA C0=112±31 &mgr;g/L, CsA C2=697±211 &mgr;g/L [range 81–1,580 &mgr;g/L], CsA dose [mg/day]=208±61, CsA dose [mg/kg/day]=2.8±1.1, and S-creatinine=141±58 &mgr;mol/L). A univariate analysis of variance showed that patients with C2 levels between 700 and 800 &mgr;g/L (n=203, S-creatinine=136±49 &mgr;mol/L) had significantly lower S-creatinine levels compared with patients with C2 levels greater than 950 &mgr;g/L (n=94, S-creatinine=152±56 &mgr;mol/L) (P <0.02). The same was true for patients with C2 levels less than 450 &mgr;g/L (n=95, S-creatinine 141±72 &mgr;mol/L) (P <0.05) when compared with patients with C2 levels greater than 950 &mgr;g/L. There was no significant difference in S-creatinine between patients in the low and intermediate C2 group; 666 patients had C0 levels in the therapeutic range (75–125 &mgr;mol/L). A linear regression showed a significant relation between S-creatinine and C2 for these patients (P =0.03). The corresponding relation between S-creatinine and C0 was nonsignificant (P =0.3). Monitoring of C2 in maintenance patients is a valuable tool to detect overexposure to CsA. Until results from prospective studies are available, we recommend C0 in the therapeutic range and reduction in CsA in overexposed patients, aiming at a C2 value between 700 and 800 &mgr;g/L.


Clinical Transplantation | 2008

Early, abrupt conversion of de novo renal transplant patients from cyclosporine to everolimus: results of a pilot study

Hallvard Holdaas; Ø. Bentdal; Per Pfeffer; L. Mjørnstedt; D. Solbu; Karsten Midtvedt

Abstract:  In a single‐center study, 20 kidney transplant patients without prior rejection were abruptly converted from cyclosporine to everolimus at seven wk post‐transplant. All patients received basiliximab induction with maintenance enteric‐coated mycophenolate sodium and corticosteroids. Biopsy‐proven acute rejection had occurred in three of 20 patients (15.0%) by the end of week seven post‐conversion. All episodes were mild and reversible, with subsequent recovery of renal function. Calculated glomerular filtration rate (GFR) improved significantly (51 ± 11 mL/min at time of conversion, 58 ± 12 mL/min at week seven post‐conversion, 57 ± 17 mL/min at month six post‐conversion; p = 0.001). No patient developed proteinuria in the nephrotic range. Twenty‐two adverse events were reported in 10 patients, three of which had a suspected relationship to everolimus. Mean leukocyte and platelet count decreased significantly, and triglyceride level increased. This study suggests that kidney transplant patients without prior rejection can be converted abruptly from cyclosporine to everolimus at seven wk post‐transplant, resulting in significantly improved renal function with no apparent increase, in risk of rejection and good tolerability.


BMC Surgery | 2001

Laparoscopic and open surgery for pheochromocytoma

Bjørn Edwin; Airazat M. Kazaryan; Tom Mala; Per Pfeffer; Tor Inge Tønnessen; Erik Fosse

BackroundLaparoscopic adrenalectomy is a promising alternative to open surgery although concerns exist in regard to laparoscopic treatment of pheocromocytoma. This report compares the outcome of laparoscopic and conventional (open) resection for pheocromocytoma particular in regard to intraoperative hemodynamic stability and postoperative patient comfort.MethodsSeven patients laparoscopically treated (1997–2000) and nine patients treated by open resection (1990–1996) at the National Hospital (Rikshospitalet), Oslo. Peroperative hemodynamic stability including need of vasoactive drugs was studied. Postoperative analgesic medication, complications and hospital stay were recorded.ResultsNo laparoscopic resections were converted to open procedure. Patients laparoscopically treated had fewer hypertensive episodes (median 1 vs. 2) and less need of vasoactive drugs peroperatively than patients conventionally operated. There was no difference in operative time between the two groups (median 110 min vs. 125 min for adrenal pheochromocytoma and 235 vs. 210 min for paraganglioma). Postoperative need of analgesic medication (1 vs. 9 patients) and hospital stay (median 3 vs. 6 days) were significantly reduced in patients laparoscopically operated compared to patients treated by the open technique.ConclusionSurgery for pheochromocytoma can be performed laparoscopically with a safety comparable to open resection. However, improved hemodynamic stability peroperatively and less need of postoperative analgesics favour the laparoscopic approach. In experienced hands the laparoscopic technique is concluded to be the method of choice also for pheocromocytoma.

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Ole Øyen

Oslo University Hospital

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Pål-Dag Line

Oslo University Hospital

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Aksel Foss

Oslo University Hospital

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