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Biomedical subjects

J Schubert

Publications and source records attributed to J Schubert.

At least 19 recordsLinked to original sources
PubMed2001

The human GPI1 gene is required for efficient glycosylphosphatidylinositol biosynthesis.

The first step in glycosylphosphatidylinositol (GPI) membrane anchor biosynthesis that is defective in paroxysmal nocturnal haemoglobinuria is mediated by an N-acetylglucosaminyl transferase expressed in the endoplasmic reticulum. Six human genes encode subunits of this enzyme, namely PIG-A, PIG-C, PIG-H, PIG-P, GPI1, and DPM2. Here, the human GPI1 gene is characterised. This gene is organised into eleven exons. The locus was mapped to chromosome 16p13.3 near the haemoglobin alpha chain locus. GPI1 is expressed ubiquitously in human cells and tissues. Expression levels are markedly elevated in haematopoietic tissues (bone marrow, foetal liver). To determine whether human GPI1 is essential for human GPI biosynthesis, antisense RNA was expressed in HEK293 cells. Transfectants exhibited a marked but incomplete decrease in the expression of a GPI-linked reporter protein, confirming that GPI1 is required for efficient GPI biosynthesis. In contrast, expression of GPI-linked proteins is normal in lymphatic cell lines from individuals with the alpha thalassaemia/mental retardation syndrome, which is characterised by large deletions from chromosome 16p removing one of the two GPI1 alleles along with the haemoglobin alpha locus. In conclusion, GPI1 plays an important role in the biosynthesis of GPI intermediates. Due to its autosomal localisation, the heterozygous deletion of GPI1 does not lead to an overt defect in the expression of GPI-linked proteins.

Cell Line, Transformed↗
PubMed2001

Preceding infections, immune factors, and outcome in Guillain-Barré syndrome.

OBJECTIVE: To test the hypothesis that different preceding infections influence the neurophysiologic classification and clinical features of Guillain-Barré syndrome (GBS). METHODS: We tested pretreatment sera, 7 +/- 3 (mean +/- SD) days from onset, from 229 patients with GBS in a multicenter trial of plasma exchange and immunoglobulin, for serological markers of infection, adhesion molecules, and cytokine receptors, and compared these with neurophysiologic and clinical features. RESULTS: Recent infection by Campylobacter jejuni was found in 53 patients (23%), cytomegalovirus in 19 (8%), and Epstein-Barr virus in four (2%). Patients with C. jejuni infection were more likely than others to have neurophysiologic criteria of axonal neuropathy or inexcitable nerves, antiganglioside GM(1) antibodies, pure motor GBS, lower CSF protein, and worse outcome. Patients with cytomegalovirus infection were younger and more likely than others to have raised serum concentrations of molecules important in T lymphocyte activation and migration, soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble leukocyte selectin, and soluble interleukin-2 receptor (sIL-2R). Concentrations of sICAM-1 and soluble tumor necrosis factor receptor were higher in patients with inexcitable nerves than those with demyelinating neurophysiology. Logistic regression analysis showed death or inability to walk unaided at 48 weeks were associated with diarrhea, inexcitable nerves, severe arm weakness, age over 50, raised sIL-2R concentration and absence of immunoglobulin (Ig) M antiganglioside GM(1) antibodies. CONCLUSIONS: Subtypes of GBS defined by preceding infections were only approximately associated with different patterns of clinical, neurophysiologic, and immunologic features. A single infectious agent caused more than one type of pathology in GBS, implying interaction with additional host factors. Most patients had no identified infection.

Antibodies↗
PubMed2001

The male chronic pelvic pain syndrome.

Suffering chronic pain is a common and debilitating problem that significantly impairs the quality of life of affected patients. Because we continue to struggle with chronic pelvic pain disorders both diagnostically and therapeutically, a neuro-behavioral perspective should be used in an attempt to explain pathways and neurophysiological mechanisms, and to improve diagnostics and treatment of male pelvic pain. First, however, malignant and acute/chronic bacterial disease has to be excluded as a cause of chronic pain in every single case. Then diagnostic approaches should screen for lower urinary tract dysfunction, pelvic floor functional disorders, and disturbed reflex integrity within the pelvic area. Treatment approaches for the male chronic pelvic pain syndrome could be divided into causal and symptomatic. Causal treatment approaches try to influence basic mechanisms generating and supporting chronic pain. In most cases a symptomatic approach is needed to relieve pain immediately. Because generally accepted treatment protocols and studies are missing, the following approach in the individual patient is recommended: (1) symptomatic treatment for immediate pain relief, (2) diagnostic work-up, (3) causal treatment trial.

Biofeedback, Psychology↗
PubMed2001

Evaluation of a pan-reactive hantavirus enzyme immunoassay and of a hantavirus immunoblot for the diagnosis of nephropathia epidemica.

BACKGROUND: Nephropathia epidemica (NE) caused by the hantavirus serotype Puumala (PUUV) is endemic in large parts of Europe. The prognosis of this disease is usually good. However, a rapid serological diagnosis is important to differentiate NE from potentially more severe renal conditions. OBJECTIVE: To evaluate the diagnostic usefulness of a novel pan-reactive hantavirus enzyme immunoassay (EIA) and of a novel hantavirus immunoblot (IB). STUDY DESIGN: Three groups of serum samples were tested with both assays: 79 samples from 43 patients with acute NE, 27 samples from healthy adults, and 29 tricky samples from patients with autoantibodies, with acute Epstein-Barr virus (EBV) or cytomegalovirus (CMV) infections, and from pregnant women. RESULTS: With the EIA, all but two of the early samples of the NE patients and all of the follow-up samples were positive for hantavirus IgG. All control samples were negative. The IgM EIA was positive in 42 of the 43 primary NE samples. Weak IgM EIA reactions were observed for some of the serum samples from patients with acute EBV and CMV infections. Optimal sensitivity and specificity values for the EIA were achieved when both the IgG and the IgM results were considered for the diagnosis of acute NE. All of the early NE samples reacted with the hantavirus nucleocapsid proteins in the IgG IB and all but one of these samples in the IgM IB. Cross reactions between the PUUV and the Hantaan antigens were very common. Several of the control samples did show borderline or positive bands, but these were mostly bands against only one hantavirus antigen in either the IgG or the IgM IB. The presence of at least three hantavirus bands (PUUV or HTNV) in the IgG and IgM assays was highly predictive of acute NE. CONCLUSION: Both assays were highly sensitive for the diagnosis of acute NE. However, the specificity of the IB IgM was only 76%. The specificity of both the IB and the EIA can be increased by modifications of the result interpretation.

Acute Disease↗
PubMed2001

Dissection of RNA-mediated ryegrass mosaic virus resistance in fertile transgenic perennial ryegrass (Lolium perenne L.).

Ryegrass mosaic virus (RgMV) frequently reduces yield and persistence of perennial ryegrass. We introduced an untranslatable RgMV coat protein (RgMV-CP) gene into perennial ryegrass using particle bombardment to explore the potential of RNA-mediated virus resistance. Nine months after inoculation with the RgMV-Bulgaria strain, the most resistant transgenic line showed no immuno-detectable RgMV-CP in all replications of the primary transformant and a sexual progeny. A significant influence of the transgenic line, virus strain and the period after inoculation on the RgMV level was observed. Typical examples of recovery resistance from initially susceptible plants were not identified. Molecular analysis revealed RgMV resistance operates by targeted RNA degradation resulting in post-transcriptional transgene silencing (PTGS) along with inhibition of virus RNA replication and was not associated with a threshold of transgene expression. Suppression of PTGS by RgMV differed significantly in two progenies with identical RgMV-CP transgene integration and a similar RgMV-CP transgene methylation pattern, suggesting the presence of quantitative components controlling the stability of PTGS in perennial ryegrass. This study extends RNA-mediated virus resistance, post transcriptional gene silencing and crop improvement by genetic engineering to an agronomically important perennial monocot.

Capsid↗
PubMed2001

Computerized contrast angiosonography: a new diagnostic tool for the urologist?

OBJECTIVES: To evaluate the diagnostic potential of echo-enhanced ultrasonography (US) for depicting the vascularization pattern of renal cell carcinoma (RCC), and calculating the first-pass effect using harmonic imaging, against that obtained by triphasic helical computed tomography (CT). PATIENTS AND METHODS: Sixty patients with surgically confirmed RCC underwent US using B-mode and power Doppler methods with or without an intravenous microbubble echo-enhancing agent. After depicting and defining the tumour extent by B-mode US, the first-pass effect/enhancement by the echo-enhancing agent within the lesion, and that of a reference area of unaffected renal cortex, were recorded on-line by calculating the mean pixel intensity. Time-intensity curves, i.e. the rise time and gradient of both the suspected tumour and reference areas, were constructed. RESULTS: Using B-mode US, the extent of all tumours was delineated (mean tumour size 3.8 cm, SD 0.6). After applying the microbubble agent all tumours were enhanced, whereas the perfusion was decreased (in 48%), increased (in 16%) or similar (in 36%) compared with the cortical reference area. Using the Hounsfield classification, these results correlated well with the hypo/hypervascularity shown on CT. CONCLUSION: Ultrasonography has considerable potential in diagnosing RCC, if combined with echo-enhancing methods, harmonic imaging and computer-based calculation of tumour vascularization. Dynamic US studies should provide a diagnostic yield similar to that of CT.

Carcinoma, Renal Cell↗
PubMed2001

[10 years experience with extracorporeal membrane oxygenation].

OBJECTIVE: Extracorporeal membrane oxygenation (ECMO) is a supportive therapy used for severe acute respiratory distress syndrome (ARDS). We present outcome, clinical parameters, and complications in a cohort of 245 ARDS patients of whom 62 were treated with ECMO. METHODS: Data of all ARDS patients were prospectively collected between 1991 and 1999. Outcome and clinical parameters of patients treated with and without ECMO were evaluated. RESULTS: Hundred-thirty-eight patients were referred from other hospitals, 107 were primarily located in our hospital. About one fourth of these patients was treated with ECMO. The survival rate was 55% in ECMO patients and 61% in non-ECMO patients. ECMO resulted in very few complications, one of them was fatal. No parameter before or during ECMO could be used to predict the individual prognosis. CONCLUSION: ECMO is a therapeutic option for patients with severe ARDS, likely to increase survival. However, a randomized controlled study proving its benefit is still awaited. Until the development of a causal or otherwise superior therapy ECMO should be used in selected patients.

Adult↗
PubMed2001

Volume-dependent compliance and ventilation-perfusion mismatch in surfactant-depleted isolated rabbit lungs.

OBJECTIVE: Volume-dependent alterations of lung compliance are usually studied over a very large volume range. However, the course of compliance within the comparably small tidal volume (intratidal compliance-volume curve) may also provide relevant information about the impact of mechanical ventilation on pulmonary gas exchange. Consequently, we determined the association of the distribution of ventilation and perfusion with the intratidal compliance-volume curve after modification of positive end-expiratory pressure (PEEP). DESIGN: Repeated measurements in randomized order. SETTING: An animal laboratory. SUBJECTS: Isolated perfused rabbit lungs (n = 14). INTERVENTIONS: Surfactant was removed by bronchoalveolar lavage. The lungs were ventilated thereafter with a constant tidal volume (10 mL/kg body weight). Five levels of PEEP (0-4 cm H2O) were applied in random order for 20 mins each. MEASUREMENTS AND MAIN RESULTS: The intratidal compliance-volume curve was determined with the slice method for each PEEP level. Concurrently, pulmonary gas exchange was assessed by the multiple inert gas elimination technique. At a PEEP of 0-1 cm H2O, the intratidal compliance-volume curve was formed a bow with downward concavity. At a PEEP of 2 cm H2O, concavity was minimal or compliance was almost constant, whereas higher PEEP levels (3-4 cm H2O) resulted in a decrease of compliance within tidal inflation. Pulmonary gas exchange did not differ between PEEP levels of of 0, 1, and 2 cm H2O. Pulmonary shunt was lowest and perfusion of alveoli with a normal ventilation-perfusion was highest at a PEEP of 3-4 cm H2O. Deadspace ventilation did not change significantly but tended to increase with PEEP. CONCLUSIONS: An increase of compliance at the very beginning of tidal inflation was associated with impaired pulmonary gas exchange, indicating insufficient alveolar recruitment by the PEEP level. Consequently, the lowest PEEP level preventing alveolar atelectasis could be detected by analyzing the course of compliance within tidal volume without the need for total lung inflation.

Animals↗
PubMed2001

Renal cell carcinoma in renal graft recipients and donors: incidence and consequence.

INTRODUCTION AND OBJECTIVES: Numerous studies have reported an increasing incidence of small renal cell carcinoma (RCC). De novo RCC in a renal allograft is a rare event and has special implications in renal transplant recipients. The objective of this study was to retrospectively evaluate the incidence of RCC in renal graft recipients and donors and to determine a procedure in cases with newly detected small renal tumors at the time of kidney preparation before transplantation. MATERIAL AND METHODS: We mailed a questionnaire to 38 German transplant clinics and received answers from 27 centers. A total of 10,997 renal graft recipients were included in the period of 1990-1998. RESULTS: In 30 kidneys (0.273%) RCC was detected at the time of preparation before transplantation. There were 23 male and 3 female donors. No bilateral RCC was described. The mean age of the donors with RCC was 50.9 years (range 37-72 years). The tumors had a mean size of 2.2 cm (range 0.4-6 cm). 67% of the patients had a renal tumor smaller than 20 mm. In 26/27 centers the decision to transplant relies on the result of the immediate section for microscopic examination. 16 patients (0.145%) developed RCC 3-12 years after renal transplantation (mean 7.4 years). The mean tumor size was 2.5 cm (range 2-2.8 cm). In 50% a grade 1 and in the other 50% a grade 2 carcinoma was found. CONCLUSIONS: Because of the RCC incidence in donor candidates we recommend an ultrasound screening of the native kidneys before renal explantation and an immediate preparation of the kidney surface especially in donors older than 45 years. In cases with small renal lesions we recommend an immediate section for microscopic examination before transplantation to prevent tumor implantation into an otherwise healthy patient. The frequency of RCCs after renal transplantation necessitates careful clinical and instrumental examinations in organ-transplanted recipients both before and at regular intervals after transplantation, including the patient's kidneys.

Adult↗
PubMed2001

Endocrine alteration in the adrenal gland in kidney transplant patients.

INTRODUCTION: Endocrine alterations associated with chronic renal failure have been reviewed recently. Some of these alterations are of clinical relevance. The aim of this study was to investigate the effect of renal transplantation on the endocrine system of the adrenal gland of the transplant recipients. METHODS: The serum angiotensin-converting enzyme (SACE), plasma renin (PR) and plasma aldosterone (PA) were examined in 30 patients before and after renal allotransplantation. Additionally measured parameters were blood pressure, serum creatinine, potassium, sodium, the duration of dialysis and immunosuppressive medication. RESULTS: Six weeks after renal transplantation, serum creatinine decreased from 820.07 +/- 172.01 to 138.12 +/- 67.54 micromol/l. In the same period, serum potassium decreased from 5.42 +/- 0.89 to 4.17 +/- 0.42 mmol/l. PA and PR decreased from 1,150.84 +/- 976.06 to 233.52 +/- 217.07 micromol/l, and from 121.07 +/- 100.12 to 26.16 +/- 10.86 microU/ml, respectively. SACE decreased from 0.21 +/- 0.21 to 0.13 +/- 0.11 micromol/l. No significant correlation was seen with blood pressure, serum sodium, the duration of dialysis and immunosuppressive drugs. Additionally, 2 patients with acute renal graft dysfunction showed significant increases in PR and PA. After successful treatment both levels declined very quickly to prerejection levels. Patients after binephrectomy show no elevation in PR (5-47 microU/ml) or PA (21-416 micromol/l) neither before nor after renal transplantation. CONCLUSIONS: We conclude that renal transplantation has profound effects on the recipient's renin-angiotensin-aldosterone system. Because of the rapid depression after renal transplantation, it does not appear to be involved in the pathogenesis of post transplantation hypertension but may reflect a role for repair processes after renal allotransplantation.

Adrenal Gland Diseases↗
PubMed2001

Interferon-alpha suppresses the antiapoptotic effect of NF-kB and sensitizes renal cell carcinoma cells in vitro to chemotherapeutic drugs.

BACKGROUND: Immunochemotherapy (ICT) with interleukin-2 (IL-2) and interferon-alpha (IFNalpha) with a secondary effector (5-fluorouracil, 5 FU) is the only promising treatment for advanced renal cell carcinoma (RCC). With IFNalpha, besides the activation mechanisms of the immunosystem, a direct antitumor effect on tumor cells is expected. MATERIALS AND METHODS: NF-kB activity in three permanent cell lines (Hep2, HepG2, HT29) and in primary RCC cell lines was measured after incubation with tumor necrosis factor-alpha (TNFalpha), IFNalpha, IFN-gamma, TNFalpha+IFNalpha, and IFNgamma+TNFalpha, respectively. NF-kB activity and induction of apoptosis by chemotherapeutic drugs (5FU and doxorubicin) were determined in cells transfected with a constitutively active NF-kB p65 or a dominant negative IkB. RESULTS: NF-kB signaling induced by TNFalpha is suppressed by IFNalpha and IFNgamma in the permanent cell lines and in the primary RCC tumor cell cultures. In an in vitro ICT model we show that pretreatment of RCC with IL-2 and IFNalpha leads to a diminished NF-kB response to TNFalpha. In certain tumors, this correlates with increased susceptibility to investigated chemotherapeutic drugs as shown by annexin stain and cell elimination. Modulation of the cellular NF-kB state by a constitutively active p65 or a dominant negative IkB mimics this effect. The IkB construct leads to the same effects as IL-2/IFNalpha pretreatment as shown by predominant elimination of the transfected cells from the overall population, while introduction of p65 leads to a partial rescue from the effect of IL-2 and IFNalpha. The described effect, however, applies only to a selection of primary cell cultures. CONCLUSIONS: Besides the immunomodulation effects, treatment of RCC with IL-2/IFNalpha leads to a proapoptotic state in certain tumors. The relevant mediator seems to be IFNalpha by suppression of the antiapoptotic effect of NF-kB. These data can provide an experimental base for correlation with real patient outcome after ICT.

Antineoplastic Agents↗
PubMed2001

Differential expression of cytokines and cytokine receptors in renal cell carcinoma.

Modulation of immunomechanisms by tumor cells can be caused by secretion of cytokines. In vitro data are usually gained in culture systems. It is debatable whether these systems are representative of the conditions inside the respective tumor tissues. Immunohistochemical studies of tumor tissue cryostats were compared with those in matched primary renal cell carcinoma tumor cell cultures. Results were correlated with histopathological characteristics and the in vitro cytotoxic effect of autologous tumor infiltrating lymphocytes (TILs). Expression of all studied cytokines and cytokine receptors could be shown in cryostats and cell cultures, but the detection pattern varied individually. The immunohistochemical results in cryostats were in good accordance with those in cell cultures. Expression of TGFbeta1 both in cryostats and cell cultures significantly correlated with the lack of cytotoxic activity of autologous TILs. Representative data can be obtained in tumor culture systems of primary renal cell carcinoma. TGFbeta1 secretion could play an important role in the interactions between tumor and cytotoxic cells.

Carcinoma, Renal Cell↗
PubMed2000

Central nervous system neurons labeled following the injection of pseudorabies virus into the rat prostate gland.

BACKGROUND: The human prostate gland plays an important role in male fertility and is involved in different functional pathologies of the male lower urinary tract (LUT). The role of the prostate in these medical disorders is mainly unknown. Traditional surgical therapeutic attempts often fail to help these patients. For years, the clinical sciences have been stagnating due to a lack of basic science knowledge. Investigations into neuroanatomy and neurophysiology are urgently needed. Therefore, the neuroanatomy of the prostate gland in an experimental setup was explored. Recent progress in neuroscience methodology allows a transneuronal tracing by using a self-amplifying virus tracer, pseudorabies virus (PRV). METHODS: Sixty-two individual adult male Sprague-Dawley rats were used for retrograde transneuronal mapping of the spinal cord and brain stem after PRV-injection and control experiments. A PRV-tracer (5 microl, 1 x 10(8) pfu/ml) was injected into the prostate gland. After a survival time of 72, 96, or 120 hr, the animals were sacrificed. Brain and spinal cord were harvested via a dorsal laminectomy. After cutting on a freezing microtome, the tissue was immunostained for PRV. RESULTS: PRV-positive cells were found within the sacral (S1-S2) and the thoracolumbar (T13-L2) spinal cord. At the supraspinal level, positive cells were found within the following regions: nucleus raphe, lateral reticular formation, nucleus gigantocellularis, A5 noradrenergic cell region, locus coeruleus, pontine micturition center, hypothalamus, medial preoptic region, and periaquaductal gray. CONCLUSIONS: This is the first investigation on the central innervation of the prostate gland showing a broad central representation of neurons involved in the control of the prostate gland. It is obvious, comparing data from the literature, that there is a broad overlap in the innervation of pelvic visceral organs (bladder, rectum, and urethra). The appreciation of these neuroanatomical circumstances allows a growing understanding of common urological pathologies within the pelvis (pelvic pain, lower urinary tract, and bowel dysfunction).

Animals↗
PubMed2000

[Basaliomas].

Basal cell carcinoma is the most frequent skin tumor in humans. It is mostly located in the face and its incidence is steadily rising. The tumor develops from basal, undifferentiated epithelial cells of the skin and its appendices and shows locally destroying growth, but generally without metastatic outspread typical of carcinomas of other origin. The tumor does not occur on the vermilion border of the lips and in the mucosa. Surgery is the most widespread and accepted treatment of basaliomas. It gives the possibility of histologic diagnosis of the whole specimen including margins of resection and allows immediate closure of the defect by means of plastic surgical methods. Regarding aesthetic and functional demands of the region, maxillofacial surgeons have the best prerequisites for this treatment. Recent research results clearly demonstrate the role of UVB light in the etiology, which is modified or promoted by genetic factors. Because of its typical malignant properties, such as progressive growth and infiltration, the term "basalioma", which is mostly used in German, should be replaced by "basal cell carcinoma" as it is known in the international literature.

Basal Cell Carcinoma↗
PubMed2000

Ex vivo stimulation of renal tubular p-aminohippurate transport by dexamethasone and triiodothyronine in human renal cell carcinoma.

This paper is the third of a long-term planned series of papers dealing with ex vivo investigations of drug transport in human kidney. The aims of this study are (a) to investigate whether or not human renal cell carcinoma (RCC) can actively accumulate p-aminohippurate (PAH) and (b) to test the response of RCC on dexamethasone or triiodothyronine (T3) using tissue slices ex vivo. By this approach, the accumulation capacity of RCC should be stimulated as a prerequisite for an increased uptake of anti-tumour drugs. Tissue slices of RCC samples of 30 patients were incubated for 24 h in Williams medium E containing 0.01-50 microM dexamethasone or T3. Thereafter, slices were placed in PAH-containing Cross-Taggart medium, and PAH uptake into kidney tissue was measured for 2h under standardised conditions as described previously. In intact human renal cortical slices, PAH uptake capacity, expressed as slice to medium ratio (QS/M), was about 2.8 +/- 0.16 after 24 h of incubation and increased significantly in dexamethasone-containing medium in a concentration-dependent manner, up to approximately 150%, whereas T3 did not influence PAH accumulation. On the other hand, in RCC the PAH accumulation capacity was completely abolished (QsM approximately 1). However, after administration of dexamethasone, the accumulated amount of PAH increased significantly in RCC tissue in a concentration-dependent manner, up to approximately 190%. T3 was without effect in RCC, too. Surprisingly, the dexamethasone-mediated stimulation could be differentiated into responders and non-responders, with maximal effects at different concentrations for each patient. Nevertheless, the maximal transport rates remained low in RCC, even under hormone influence. In conclusion, a moderate stimulation of tubular transport capacity can be shown ex vivo in human RCC. This phenomenon is only of a relatively low degree compared with intact renal tissue. However, in principle, the response of RCC on dexamethasone could form a basis for further therapeutic strategies to overcome multi-drug resistance in RCC patients. For this purpose, additional experiments analysing the expression of transporters of the ABC cassette-type are in progress.

ATP-Binding Cassette Transporters↗
PubMed2000

Imaging in ureteral complications of renal transplantation: value of static fluid MR urography.

Ureteral obstruction is an infrequent complication after renal transplantation that may cause rapid loss of transplant function. We tested static fluid MR urography for determining the cause of graft hydronephrosis. Magnetic resonance urography was performed in nine transplants with dilated collecting systems on ultrasound. A heavily T2-weighted 3D turbo spin-echo sequence on a 1.5-T scanner was used and maximum intensity projections were obtained. The patients also underwent excretory urography (n = 1), renal scintigraphy (n = 1), antegrade pyelography (n = 3), voiding cystourethrography (n = 4), and non-enhanced CT (n = 2). Six patients had pathologic conditions including ureteral stricture, compression by lymphoceles, implantation stenosis, vesicoureteral reflux, and late-occurring transitional cell carcinoma at the implantation site. Static MRU was able to diagnose or exclude a dilation of the graft collecting system. It visualized the course of the ureters and localized the obstruction site in four of five obstructed transplants. In one case the ureter was obscured by lymphoceles, which were demonstrated by hydrographic MRU as well. The definite cause for obstruction was provided in only 2 of 5 cases. Dilation due to vesicoureteral reflux could not be differentiated. The current multimodality approach to renal transplant imaging already provides comprehensive assessment of graft hydronephrosis. Static MRU may be useful in some cases since complications associated with intravenous iodinated contrast or antegrade pyelography can be avoided. Its main drawback, the lack of functional information, may be overcome by combining it with contrast-enhanced MRU.

Adult↗