Role of anti-vimentin antibodies in renal transplantation.

BACKGROUND: The role of non-HLA antibodies in rejection is not clear. We investigate whether antibodies to vimentin are made after renal transplantation and if production is associated with interstitial fibrosis and tubular atrophy (IFTA). METHODS: In this retrospective study, sera from 70 recipients of renal allografts (40 controls, 30 IFTA) were studied. The biopsy diagnosis of interstitial fibrosis and tubular atrophy (IFTA) was based on random, cause-indicating biopsies. Sera were collected pretransplant and at 3 monthly intervals up to 5 years posttransplant or diagnosis of IFTA and assayed by ELISA for IgM and IgG anti-vimentin antibodies (AVA) and HLA antibodies. RESULTS: Mean titers of IgM AVA were higher at every year after transplantation compared with pretransplant for both IFTA and controls groups (P<0.001). There was no difference in the mean level of IgM AVA achieved by IFTA and control groups. The mean pretransplant levels of IgG AVA in the IFTA and control group were 18.2±11.7 and 11.0±8.1, respectively (P=0.001). There was a significant increase between the pretransplant mean levels of IgG AVA and the levels at years 1 to 4 in the IFTA group (years 1-3, P<0.0001, year 4 P=0.003) but not in the controls. There was no significant difference between the numbers of IFTA or control patients achieving a positive value (mean+2SD of pretransplant antibody titers) of IgM AVA (50% versus 37.5%, respectively) or IgG AVA (26.6% versus 12.5%, respectively). There was no association between production of HLA and AVA antibodies. CONCLUSION: Posttransplant production of IgM AVA is not associated with IFTA. The production of IgG AVA by a minority of IFTA patients suggests that in some individuals, IgG AVA may be involved in the pathology of IFTA.

Congenital anterior urethral diverticulum in a male teenager: a case report and review of the literature.

We present the case of a 13-year-old boy with a congenital anterior urethral diverticulum. This is a rare condition in males which can lead to obstructive lower urinary tract symptoms and urosepsis. Diagnosis is by urethroscopy and radiological imaging. Surgical treatment can be open or endoscopic. Long-term followup is required to check for reoccurrence of the obstruction.

Urological malignancy after renal transplantation.

Immunosuppression in solid-organ recipients is associated with a greater risk of de novo malignancy after transplantation; herein we report the UK transplant registry (UKTR) database of urological cancer after renal transplantation in the UK transplant population. From September 1999 to January 2006 there were 10,847 kidney recipients with at least one period of follow-up reported after a kidney transplant (mean age at transplantation 42.4 years, sd 15.5; 6685 male, 61.6%, and 4162 female, 38.3%). The recipients represent a homogenous group who received different immunosuppression regimens. Skin cancer was excluded from the study. Unfortunately, the UKTR does not collect information about the presence or absence of cancer, either at registration onto the transplant waiting list or at transplantation. In all, 214 (1.9%) patients were reported to have a subsequent urological malignancy diagnosed among the 10,847 recipients. The UKTR was used to identify patients who developed urological malignancies after renal transplantation, which is a challenging event after solid-organ transplantation. Regular surveillance to diagnose early occurrence and adjustment of immunosuppression might be beneficial. In the presence of metastatic disease, chemotherapy treatment with adjustment or cessation of immunosuppressive therapy is required.

The influence of changes in extracellular and intracellular sodium concentration on detrusor contractility.

OBJECTIVE: To determine the role of Na+-Ca2+ exchange in the regulation of isolated detrusor smooth muscle contractility. MATERIALS AND METHODS: Isolated guinea-pig detrusor strips were used to record isometric tension generated by; (a) electrical-field stimulation to elicit nerve-mediated responses; and (b) adding carbachol or superfusing with a high-K+ solution. The [Na+] gradient between extracellular and intracellular compartments was altered by: (i) reducing superfusate [Na+] in stages from 140.2 to 10.2 mm; (ii) addition of the cardiac glycoside strophanthidin (200 microm). RESULTS Reducing extracellular [Na+] reversibly reduced the magnitude of nerve-mediated contractions but increased the resting tension and magnitude of carbachol-induced contracture. The mean (sd) [Na+] required for a half-maximum effect on attenuating contractions, at 85.9 (6.2) mm, and developing contracture, at 59.1 (14.3) mm, were significantly different. The time constants of changes to nerve-mediated contractions and carbachol contracture were also significantly different, at 147 (5) vs 1207 (386) s, respectively. These differences suggest that separate mechanisms influence nerve-mediated contraction and contracture in low-Na+ solutions. Exposure to the cardiac glycoside strophanthidin produced a similar effect to low-Na+ solutions for carbachol contracture. Low-Na+ solutions had no significant effect on contractures induced by high extracellular [K+]. CONCLUSION Reducing the transmembrane [Na+] difference increases intracellular [Ca2+]. This increase is largely accommodated in intracellular stores, that can be released by exogenous carbachol. The results are consistent with the presence of a functional Na+-Ca2+ exchanger in the surface membrane. The lack of effect of low-Na+ solutions on contractures evoked by membrane depolarization is consistent with this conclusion. The reduction of the nerve-mediated contraction by low-Na+ solution might result from blockade of the nerve action potential.

Bladder neck contracture after radical retropubic prostatectomy.

OBJECTIVE: To examine the incidence, management and outcome of vesico-urethral anastomotic strictures after bladder-neck sparing radical retropubic prostatectomy (RRP). PATIENTS AND METHODS: We assessed the incidence, management and outcome of anastomotic strictures in 510 consecutive patients (mean age 61 years, range 45-76) who had open RRP by one surgeon between 1994 and 2003. RESULTS: The mean (range) follow-up was 30 (2-89) months; 48 patients (9.4%) developed an anastomotic stricture. Dilatation of the stricture was an effective treatment, with few patients requiring further treatment. CONCLUSION: Stricture of the vesico-urethral anastomosis after bladder-neck sparing RRP is relatively frequent but can usually be successfully managed with one graduated dilatation under light sedation.