PubMed Health⌕ Search

Biomedical subjects

J Steiger

Publications and source records attributed to J Steiger.

At least 19 recordsLinked to original sources

Prevalence and risk factors of non-adherence with immunosuppressive medication in kidney transplant patients.

Non-adherence with immunosuppressive regimen is a major risk factor for poor outcome after kidney transplantation. Identifying patients at risk for non-adherence requires understanding the risk factors for non-adherence. This prospective study included a convenience sample of 249 adult kidney transplant patients >1 year post-transplant. Non-adherence was monitored electronically using MEMS(R). Selected socio-economic, therapy-, patient-, condition- and healthcare team-related risk factors for non-adherence were assessed. Period prevalences were expressed as the percent of prescribed doses taken (taking adherence), the percent of correctly dosed days (dosing adherence), the percentage of inter-dose intervals not exceeding 25% of the prescribed interval (timing adherence), and the number of drug holidays per 100 days (no intake for > 48 h if once daily or for > 24 h if twice daily intake). Testing occurred by simple mixed logistic regression analysis. Factors significant after correction for multiple testing were entered into a multiple logistic regression model. Mean taking, dosing, timing adherence, and drug holidays were 98%, 96%, 93%, and 1.1 days, respectively. Non-adherence was associated with lower self-efficacy, higher self-reported non-adherence, no pillbox usage, and male gender. Adherence declined between Monday and Sunday. This study provides a framework for identifying patients at risk for non-adherence and for developing adherence-enhancing interventions.

Adult↗

Morphology and nrITS phylogeny of the genus Pinguicula L. (Lentibulariaceae), with special attention to embryo evolution.

The genus Pinguicula (Lentibulariaceae) is unusual within the dicot order Lamiales because of the occurrence of both embryos with two cotyledons and those with just one cotyledon. In order to elucidate the infrageneric relationships and the evolutionary history of the embryo, we analysed (1) the internal transcribed spacers ITS1 and ITS2 of the nuclear ribosomal DNA (nrITS) of 29 Old and New World taxa of Pinguicula, and (2) the morphological and anatomical characters of the seeds. We suggest that the cotyledon number and spermoderm structure were quite unstable in the evolution of Pinguicula. Although basal nodes of the nrITS tree are sensitive to taxon sampling, all tree topologies found in this study imply homoplasy in the cotyledon number.

Biological Evolution↗

Duplex sonography after living donor kidney transplantation: new insights in the early postoperative phase.

AIM: Vascular complications of kidney transplantation, including transplant vein thrombosis, are relevant causes for graft loss in the early postoperative phase. However, duplex flow characteristics after living renal transplantation are widely unknown. Aim of the study was to assess renal perfusion in the postoperative period with special emphasis on the renal vein. METHODS: 22 consecutive kidney graft recipients and their donors were included and prospectively followed up for three months. The following Doppler parameters were collected: in the donor before operation: the intrarenal resistive index (RI), in the recipient after transplantation and at one and three months: the intrarenal RI, peak flow velocities and area under the curve in the renal vein, as well as peak systolic velocities of the iliac and renal artery. RESULTS: None of the 22 transplants failed due to vascular complications. Highest median venous (92 cm/s [range 22-211]) and arterial peak velocities (271.5 cm/s [141.5-458]) were observed close to the anastomosis immediately after transplantation. During follow-up, flow parameters significantly decreased at three months (44.3 cm/s [13.3-156.9] and 186.8 cm/s [105.5-267.5]). The RI decreased from donor to recipient at the day of operation due to tachycardia (0.65 to 0.60; P = 0.06). After correction for heart rate, the RI was stable during follow-up. CONCLUSIONS: Initial high peak velocities in conjunction with stable resistive indices in a cohort, free of vascular graft complications, suggest a postoperative physiologic adaptation process rather than a relevant stenosis requiring medical intervention.

Adolescent↗

The fate of C4d positive kidney allografts lacking histological signs of acute rejection.

BACKGROUND: C4d deposits in renal transplants are known to be an independent risk factor of graft failure. The current analysis evaluates the impact of C4d deposits on graft function and survival in renal transplants without morphological signs of rejection. METHODS: We retrospectively analyzed diagnostic transplant biopsies performed due to allograft dysfunction from June 1994 to June 2001 at the University Hospital in Basel. STUDY GROUP: Grafts/patients with focal or diffuse positivity of C4d along peritubular capillaries; absence of morphological signs of acute cellular and/or humoral rejection; up to 3 year follow-up analysis post index biopsy. Patients treated with anti-rejection therapy or an increase in maintenance immunosuppression post biopsy (intervention group = IG) were compared to patients with unaltered immunosuppression (standard group = SG). RESULTS: Study group: 22 biopsies/patients out of 400 biopsies (5%) were included into the study, 17 in the SG and 5 in the IG. Patient survival (1-/3-years): SG: 100/94%, IG: 80/80%; graft survival censored for death (1-/3-years): SG: 82.5/68.8%, IG: 100/100%; serum creatinine (micromol/l) at index biopsy/1-year/3-years: SG: 221 +/- 70/231 +/- 103/245 +/- 124, IG: 217 +/- 100/143 +/- 28/177 +/- 55; acute rejection episodes within 1 year post index biopsy: SG: 4 (4 patients), IG: 1 (1 patient); all differences not significant. Lowest serum creatinine within 4 weeks post index biopsy (IG vs. SG): 108 +/- 25 vs. 181 +/- 61, p = 0.02. CONCLUSIONS: C4d positivity in kidney transplants lacking histological evidence of acute rejection is not associated with rapid functional graft deterioration, even in untreated cases. However, anti-rejection therapy results in the improvement of kidney function. Thus, even in grafts with normal histology, the detection of C4d in diagnostic biopsies can be interpreted as a sign of "smoldering" rejection that benefits from therapy.

Acute Disease↗

No indication for activation of exogenous retroviruses in patients with renal allograft rejection.

AIM: Reactivation of latent BK virus in kidney-transplanted patients results in severe graft dysfunction. The role of retroviruses infecting also latently target cells is not investigated so far in this setting. We determined the presence or induction of retroviruses in sera of immunosuppressed patients with renal allografts at the timepoint of organ rejection or ongoing polyomavirus nephropathy. PATIENTS AND METHODS: Sera of patients with acute kidney rejection or polyomavirus nephropathy (n=25) and controls (n=8) were tested for reverse transcriptase activity by the ultrasensitive product enhanced reverse transcriptase (PERT) assay. In parallel, kidney biopsies were investigated for histological signs of kidney rejection or polyomavirus nephropathy confirmed by either immunofluorescence or immunohistochemistry. RESULTS: None of the investigated sera, specifically those of patients with ongoing BK virus nephropathy, indicated reverse transcriptase activity. CONCLUSION: Our results do not support the idea of the induction of known or unknown retroviruses in patients with kidney transplantation, even under highly immunosuppressive therapies.

Adult↗

Retroperitoneoscopic living donor nephrectomy: a comparison with the open approach in respect of early postoperative pain management.

INTRODUCTION: We retrospectively compared perioperative donor outcomes and early postoperative pain control after retroperitoneoscopic (RLDN) and standard open (OLDN) living donor nephrectomy. METHODS: One hundred donors included fifty after RLDN (37 women/13 men) and 50 after OLDN (35 women/15 men) were retrospectively analyzed for basic analgesics, for opioid consumption, and for visual analog scale (VAS) to verify the experienced pain. The donors were questioned in the morning and evening of the first through fifth postoperative days. RESULTS: The mean age of both groups was equal. The mean operating time was 149.7 +/- 48.2 minutes (60 to 270) for RLDN and 164.1 +/- 30.3 minutes (60 to 240) for OLDN (P = NS). The mean warm ischemia time was 120 +/- 36 seconds (50 to 240) and 114 +/- 31 seconds (60 to 190) for the RLDN and OLDN groups, respectively (P = NS). The mean evening VAS for RLDN versus OLDN on postoperative days 1 to 5 was: 2.1 versus 2.2 (P = NS), 0.9 versus 1.8 (P = .009), 0.5 versus 1.3 (P = .016), 0.1 versus 0.7 (P = .013), and 0.1 versus 0.7 (P = .013), respectively. In both groups there was a tendency toward a higher VAS score in the morning than in the evening. RLDN donors showed significantly earlier period free of pain (VAS = 0) than those after OLDN. There was a significant difference of being free from any opiate between both groups after surgery. CONCLUSIONS: After RLDN donors experienced less postoperative pain than after OLDN over the early postoperative days. Therefore, postoperative regional anesthesia is not necessary for donors operated by a retroperitoneoscopic approach.

Adult↗

[Lupus nephritis].

Lupus nephritis is a serious complication of systemic lupus erythematodes. It is important to establish the correct diagnosis in order to initiate the optimal treatment for a specific patient. Early therapy will prevent organ damage which otherwise can dramatically increase morbidity and mortality. This article provides information about pathogenesis, manifestations, laboratory investigations, histopathology and treatment of lupus nephritis. Besides the indication for treatment the various immunosuppressive protocols are discussed. Moreover, a specific treatment option is proposed and the follow up is described.

Clinical Trials as Topic↗

[Transplantation].

Explore the source record for details and available documents.

Cell Transplantation↗

[Manually-assisted laparoscopic donor nephrectomy].

The number of patients suffering from terminal renal failure awaiting kidney transplantation has continued to increase. Since the number of available cadaver donor kidneys has largely remained unchanged, a special publicity campaign achieved that almost one-half of the kidneys transplanted in Basle come from live donors. We performed a laparoscopic live donor nephrectomy in 14 patients between March 1998 and August 1999. Despite good experience regarding transplant function and patient satisfaction, the hand-assisted technique was introduced in 1999 because of the long average operating time of 230 min (200-270) and warm ischemia time of 7.5 min (4-9). In the 33 operations performed up to now, the average operating time and warm ischemia time could be significantly reduced to 185 min (135-240) and 2.4 min (1.5-4), respectively. Most recently, the technique of retroperitoneoscopic live donor nephrectomy was successfully employed in 4 patients and could possibly represent the method of choice for the future.

Adult↗

[Renal biopsy: standard procedure of modern nephrology].

For more than 50 years, renal biopsy has been an important diagnostic procedure in modern nephrology. Increasing perfection of the biopsy technique has made the procedure very safe, with rare complications and few contraindications. Improved histological diagnostics and broader therapeutic possibilities have significantly expanded the indications. The most important indications are acute renal failure, proteinuria > 1 g/d (or 3 g/d) and nephritic urinary sediment. Complications with renal grafts provide additional indications for a renal biopsy. In addition, diabetes and monosymptomatic urinfindings (isolated haematuria) as well as pregnancy induced nephropathy are indications for a renal biopsy. The procedure is performed ambulatory or during a short hospital stay and the patient can usually be discharged after a monitoring period of eight hours.

Acute Kidney Injury↗

Cytomegalovirus infection and graft rejection in renal transplantation.

BACKGROUND: Cytomegalovirus (CMV) infection and CMV disease have been associated with acute and chronic graft rejection. The introduction of the sensitive CMV antigenemia pp65 assay for detection of CMV infection allowed us to study the time course of CMV infection and acute rejection and the long-term outcome in renal transplant recipients with and without a CMV risk constellation. METHODS: Prospective single center study including 48 renal transplant recipients at risk for CMV infection (donor and/or recipient CMV seropositive) and a control group of 36 CMV seronegative recipients of CMV seronegative kidney donors. Evidence of CMV infection was monitored by the CMV antigenemia pp65 assay every 1 to 2 weeks and compared with the occurrence of acute rejection in the posttransplant period and graft function at 5 years. RESULTS: CMV infection developed in 83% (40/48) of patients of the CMV risk group within 4 months posttransplant. A total of 18 of patients experienced an acute rejection episode (control group 16/36; P=0.65). In 12/18 CMV infection followed rejection and in three patients antigenemia preceded the diagnosis of rejection. In three patients CMV antigenemia remained negative. Five-year follow up: Patient survival (44/48 vs. 31/36; P=0.48), graft survival (38/48 vs. 27/36; P=0.79), number of patients with at least one acute rejection episode: CMV risk group: 42.1%, control group 51% (P=0.46), serum creatinine: CMV risk group:130 +/- 66 micromol/iter, control group: 126 +/- 37 micromol/ liter (P=0.56), proteinuria: CMV risk group: 0.02 +/- 0.02 g/mmol creatinine, control group: 0.02 +/- 0.02 g/mmol creatinine (P=1.0). CONCLUSION: CMV infection within 4 months posttransplant, as defined by a positive antigenemia assay was not found to be a risk factor for acute graft rejection or chronic graft dysfunction at 5 years.

Adult↗

Evidence for highly charged ion Coulomb crystallization in multicomponent strongly coupled plasmas.

Multicomponent non-neutral ion plasmas in a Penning trap consisting of Be(+) and highly charged Xe ions, having different mass-to-charge ratios than Be(+), are cooled to form strongly coupled plasmas by applying a laser-based collisional cooling scheme. The temperature of the plasma was determined from a Doppler broadened transition in Be(+). For the Xe ions, which are centrifugally separated from the Be, the Coulomb coupling parameter was estimated to be approximately 1000. Molecular dynamics simulations of the ion mixture show ordered structures, indicating crystallization of the Xe.

Journal Article↗

Diagnostic yield of bronchoalveolar lavage following renal transplantation.

Organ transplant recipients are at high risk of infectious pulmonary complications. In this retrospective study, the diagnostic yield of bronchoalveolar lavage (BAL) was evaluated in renal transplant recipients. The results were analysed in special regard to the clinical presentation of pulmonary infections and the possible impact of new immunosuppressive agents. Over a 5-year period 91 BAL were performed in 71 renal transplant recipients. Microorganisms were isolated from 69% of BAL (63/91): bacteria 32%; cytomegalovirus (CMV) 27%; Pneumocystis carinii (PC) 22%; other viruses 9% (HSV; EBV, RSV, adenovirus, HHV8); Aspergillus fumigatus 1%. Total cell counts and neutrophil counts in BAL were significantly elevated in bacterial infection, whereas BAL positive for PC showed eosinophilia (P<0.05). There was no association between clinical symptoms and the radiological pattern of infiltrates and the type of infection. Immunosuppression containing tacrolimus or mycophenolate mofetil was associated with a significantly higher percentage of PC and CMV infections compared to cyclosporin-based immunosuppression (65% vs. 30%, P<0.005). A considerable number of PC and CMV infections occurred beyond 6 months after transplantation. In conclusion, BAL has a high diagnostic yield in renal transplant recipients. Infection with CMV and PC should also be considered beyond 6 months after transplantation, and prophylaxis for opportunistic infections should be given if the immunosuppression is intensified.

Adult↗

Polyomavirus BK nephropathy in a kidney transplant recipient: critical issues of diagnosis and management.

Diagnosis of polyomavirus BK nephropathy and treatment by low-dose immunosuppression may be optimized by using surrogate markers, such as the detection of viral inclusion bearing cells in the urine and polyomavirus BK DNA in plasma by polymerase chain reaction. These markers were used prospectively in the management of a 44-year-old woman and led to the diagnosis of polyomavirus BK nephropathy at an early stage. The management was complicated by the concurrence of acute allograft rejection. Two treatment steps were initiated: antirejection therapy consisting of methylprednisolone for 3 days followed by lowering of the maintenance immunosuppression. This treatment resulted in a return of the serum creatinine concentration to the baseline of 1.6 mg/L, clearance of polyomavirus BK from plasma, and disappearance of viral inclusion bearing cells from the urine. After 2 months of stable allograft function, a control biopsy confirmed the resolution of polyomavirus BK nephropathy. Histologic signs of acute interstitial rejection were found and preemptively treated by methylprednisolone without altering the baseline regimen. Allograft function remained stable without evidence of recurrent polyomavirus BK nephropathy. This case shows the value of surrogate markers used in a prospective fashion for diagnosis and management of polyomavirus BK nephropathy with concurrent rejection.

Adult↗

Evolution and etiology of cardiovascular diseases in renal transplant recipients.

The mortality rates for CVDs in transplant recipients are greater than those in the general population (13). CVDs are a major cause of both patient and graft loss in renal transplant recipients, and improving cardiovascular health may help to extend both patient and graft survival. A complication of chronic renal failure, CVDs are frequently present in patients being considered for transplantation. Pretransplant screening, based on risk stratification, may detect pre-existing disease and identify patients likely to benefit from therapeutic strategies designed to reduce CVDs prevalence. Further studies are needed to better define the risk factors for CVDs in the renal transplant population and to evaluate the effectiveness of risk modification on the related morbidity and mortality. Risk-factor management initiated early in the course of chronic renal failure might reduce the burden of CVDs in both dialysis and transplant populations.

Adult↗

[Hematuria and proteinuria--old names, new horizons].

Gradually advanced diagnostic standards for the analysis of urine specimens during the last years led to improved clinical arguments providing important clues. Unnecessary diagnostic procedures like IVP or cytoscopy in suspected glomerular hematuria may for instance be prevented, the patients comfort enhanced and costs reduced. A possible diagnostic algorithm in a case with suspected urologic pathology is shown.

Algorithms↗