Expression of parathyroid hormone/parathyroid hormone-related peptide receptor 1 in normal and diseased bladder detrusor muscles: a clinico-pathological study.

BACKGROUND: To investigate the expression of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor 1 (PTH1R) in clinical specimens of normal and diseased bladders. PTHrP is a unique stretch-induced endogenous detrusor relaxant that functions via PTH1R. We hypothesized that suppression of this axis could be involved in the pathogenesis of bladder disease. METHODS: PTH1R expression in clinical samples was examined by immunohistochemistry. Normal kidney tissue from a patient with renal cancer and bladder specimens from patients undergoing ureteral reimplantation for vesicoureteral reflux or partial cystectomy for urachal cyst were examined as normal control organs. These were compared with 13 diseased bladder specimens from patients undergoing bladder augmentation. The augmentation patients ranged from 8 to 31 years old (median 15 years), including 9 males and 4 females. Seven patients had spinal disorders, 3 had posterior urethral valves and 3 non-neurogenic neurogenic bladders (Hinman syndrome). RESULTS: Renal tubules, detrusor muscle and blood vessels in normal control bladders stained positive for PTH1R. According to preoperative urodynamic studies of augmentation patients, the median percent bladder capacity compared with the age-standard was 43.6% (range 1.5-86.6%), median intravesical pressure at maximal capacity was 30 cmH2O (range 10-107 cmH2O), and median compliance was 3.93 ml/cmH2O (range 0.05-30.3 ml/cmH2O). Detrusor overactivity was observed in five cases (38.5%). All augmented bladders showed negative stainings in PTH1R expression in the detrusor tissue, but positive staining of blood vessels in majority of the cases. CONCLUSIONS: Downregulation of PTH1R may be involved in the pathogenesis of human end-stage bladder disease requiring augmentation.

Team-based learning, a learning strategy for clinical reasoning, in students with problem-based learning tutorial experiences.

Acquiring clinical reasoning skills in lectures may be difficult, but it can be learnt through problem-solving in the context of clinical practice. Problem finding and solving are skills required for clinical reasoning; however, students who underwent problem-based learning (PBL) still have difficulty in acquiring clinical reasoning skills. We hypothesized that team-based learning (TBL), a learning strategy that provides the opportunity to solve problems by repeatedly taking tests, can enhance the clinical reasoning ability in medical students with PBL experiences during the pre-clinical years. TBL courses were designed for 4(th) year students in a 6-year program in 2008, 2009, and 2010. TBL individual scores, consisting of a combination of individual and group tests, were compared with scores of several examinations including computer-based testing (CBT), an original examination assessing clinical reasoning ability (problem-solving ability test; P-SAT), term examinations, and Objective Structured Clinical Examination (OSCE). CBT, OSCE and P-SAT scores were compared with those of students who learned clinical reasoning only through PBL tutorials in 2005, 2006, and 2007 (non-TBL students). Individual TBL scores of students did not correlate with scores of any other examination. Assessments on clinical reasoning ability, such as CBT, OSCE, and P-SAT scores, were significantly higher in TBL students compared with non-TBL students. Students found TBL to be effective, particularly in areas of problem solving by both individuals and teams, and feedback from specialists. In conclusion, TBL for clinical reasoning is useful in improving clinical reasoning ability in students with PBL experiences with limited clinical exposure.

[Case report of rhabdoid tumor of the kidney occurring in own kidney following kidney transplantation from the living relative].

The patient was a 30-year-old man who had undergone living-donor kidney transplantation for renal failure caused by IgA nephropathy at age 29. On post-transplantation day 83, he visited our department with a chief complaint of asymptomatic hematuria. CT performed on post-transplantation day 95 revealed a tumor (size, 4 cm) in the right native kidney that had not been observed at the time of transplantation. CT performed on post-transplantation day 153 showed that the tumor had enlarged to 6 cm, while retrograde pyelogram performed on post-transplantation day 171 was negative for renal pelvic tumor. On post-transplantation day 193, radical right nephrectomy was performed. The tumor had directly invaded the diaphragm and the lower surface of the liver, and was histopathologically diagnosed as rhabdoid tumor of the kidney. As the pathological tissue was extremely malignant, hepatic posterior segmentectomy, right adrenalectomy, and lymph node dissection were further performed for metastases on post-transplantation day 200. On the 23rd day after radical right nephrectomy (post-transplantation day 216), the patient developed dyspnea. Chest CT showed pleural effusion, hemothorax in right lung and metastases in both lungs. The patient's general status gradually worsened thereafter, and he died on the 53rd day after radical right nephrectomy (post-transplantation day 246). Rhabdoid tumor of the kidney is a rare renal tumor that affects children, and only four adult cases have been reported to date. We report our experience with this rare case.

Screening of vesicoureteral reflux in pediatric patients with kidney transplantation showing non-specific interstitial fibrosis and tubular atrophy with interstitial Tamm-Horsfall protein deposits in protocol allograft biopsy.

Interstitial fibrosis and tubular atrophy (IF/TA) in kidney allografts are induced by multiple factors, and although much effort has been devoted on the classification of IF/TA, clarification of the causes of non-specific IF/TA is equally important for appropriate therapy. Tamm-Horsfall protein (THP) in renal tissue can be a useful marker for the histological expression of urine backflow and suspected vesicoureteral reflux (VUR). Here, we examined the presence of VUR in pediatric recipients with interstitial THP deposits in kidney allografts to clarify the cause of non-specific IF/TA. Ten pediatric patients showing interstitial THP deposits with non-specific IF/TA were enrolled and voiding cystourethrography was performed. Major histological findings of these patients were interstitial mononuclear cell infiltration and fibrosis associated with interstitial THP deposits. The semiquantitative grading scores of IF/TA were as follows: (i) mild IF/TA (n = 3); (ii) moderate IF/TA (n = 3); and (iii) severe IF/TA (n = 4). In the severe grade, diffuse interstitial mononuclear cell infiltrates were prominent with the appearance of thyroidization classically observed in chronic pyelonephritis. Eight of ten patients (80%) had VUR into the graft. Although symptomatic pyelonephritis was not observed in any of the patients, asymptomatic bacteriuria was detected in 40.0% of the patients. There was no significant correlation between VUR grade and IF/TA histological score. The patients without VUR also showed mild or severe IF/TA. Therefore, VUR and urinary flow stasis accompanied by asymptomatic urinary tract infection appear to be the causes of interstitial mononuclear cell infiltration and fibrosis associated with interstitial THP deposits in kidney allografts.

Impact of arterial occlusion during partial nephrectomy on residual renal function: an evaluation with (99m)technetium-dimercaptosuccinic acid scintigraphy.

BACKGROUND: Partial nephrectomy (PNx) has been performed with temporary renal arterial occlusion and in situ renal hypothermia (conventional PNx). However, the impact of temporary renal arterial occlusion on residual renal function has not been well assessed. To address this question, we performed renal scintigraphy with (99m)technetium-dimercaptosuccinic acid (DMSA) for the quantitative measurement of postoperative residual renal function after conventional PNx and partial nephrectomy without arterial occlusion (non-clamping PNx). METHODS: Thirty-four patients underwent postoperative DMSA scintigraphy after PNx for renal cell carcinoma. No obvious difference in preoperative renal function between the diseased kidney and the contralateral kidney was found in any of the patients. Of these patients, 24 underwent conventional PNx, and 10 underwent non-clamping PNx. Residual renal function was evaluated using the relative DMSA uptake of the operated kidney. RESULTS: The relative DMSA uptake of the operated kidney was 39.9 +/- 7.3% (25.1-58.8) after conventional PNx compared to 34.8 +/- 8.9% (13.5-45.5) after non-clamping PNx. This difference was not statistically significant (P = 0.15). Total ischemic time during conventional PNx had no adverse influence on the residual renal function. In the analysis of the other determinant factors influencing residual renal function, tumor size was the only significant factor that inversely correlated with the relative DMSA uptake. CONCLUSION: Our results showed that arterial clamping during PNx has no negative impact on the functional residual capacity as long as insitu renal hypothermia is adequately performed.