Akihiro Usui

Nocturnal enuresis and overactive bladder in children: An epidemiological study

Aims:  To investigate the prevalence and characteristics of nocturnal enuresis (NE) and to examine the prevalence of overactive bladder (OAB) symptoms in primary schoolchildren.

Analysis of growth factors in renal cell carcinoma.

Tissue extracts prepared from human renal tissue, renal cell carcinoma and serum-free conditioned media of ACHN cells and A498 cells, cell line originated from human renal cell carcinoma, stimulated DNA synthesis of BALB/c 3T3 cells. The activity (growth factor activity) was significantly higher in renal cell carcinoma than in normal tissues. Radioreceptor assay revealed that the contents of epidermal growth factor and type alpha transforming growth factor in the tissue extracts from renal cell carcinoma and conditioned media from renal cell carcinoma cell lines were below detectable level. Most of growth factor activity of the tissue extracts and conditioned media showed high affinity for heparin-Ultrogel, indicating that the major growth factor activity was due to heparin-binding growth factor(s). In addition, renal cell carcinoma contained growth factor activity for ACHN cells, which did not show specific affinity for heparin-Ultrogel.

Metastatic Renal Cell Carcinoma Arising in a Native Kidney of a Renal Transplant Recipient

We report a case of metastatic renal cell carcinoma arising in the native kidney of a renal transplant recipient. A 39-year-old man, who had undergone living renal transplantation from his mother at age 32, presented with complaints of paraplegia of the leg caused by a pathological fracture of the 3rd lumbar vertebra. The bone tumor was extirpated and pathological examination revealed metastatic adenocarcinoma. Abdominal computerized tomography showed a tumor in the right native kidney. Right nephrectomy and resection of the right 7th rib tumor were performed. Pathological evaluation demonstrated renal cell carcinoma of the right native kidney (pT2bpN0pV0M1, mixed cell type, grade 2). Postoperatively, cyclosporine was discontinued and natural interferon-alpha was given. The remaining bone metastasis had completely resolved with no significant sign of rejection 1 year after surgery.

ENDOSCOPIC SUBURETERAL GLUTARALDEHYDE CROSS-LINKED COLLAGEN INJECTION FOR THE TREATMENT OF SECONDARY VESICOURETERAL REFLUX: COMPARISON WITH PRIMARY VESICOURETERAL REFLUX IN ADULTS

PURPOSE We assessed the effectiveness of endoscopic subureteral glutaraldehyde cross-linked collagen injection for treating vesicoureteral reflux in patients with vesicoureteral disorders. MATERIALS AND METHODS All 51 ureters studied had grade II or greater vesicoureteral reflux. We treated 18 patients (24 refluxing ureters) with secondary and 17 adults (27 refluxing ureters) with primary vesicoureteral reflux. The primary group served as controls to establish normal urination. A total of 14 patients with secondary vesicoureteral reflux had a low compliant autonomous bladder, including 11 with myelodysplasia and 3 after pelvic surgery and radiotherapy. One patient had an unstable bladder due to cerebral palsy and 3 had anatomical abnormalities of the urinary tract. We evaluated the estimated reflux-free rate in the secondary and adult primary vesicoureteral reflux groups. RESULTS Repeat injection was required in 24 ureters because of recurrent reflux. Average injected volume in the secondary and primary groups was 2.72 and 2.88 ml. per refluxing unit, respectively. The estimated reflux-free rate after the initial injection decreased gradually to about 35% in each group, while 12 and 24 months after the last injection it remained constant at 70% in the secondary group but decreased from 84.7% to 62.1% in the primary group. The percent of late recurrence was higher in the primary group. CONCLUSIONS Long-term efficacy of the endoscopic correction of vesicoureteral reflux in the secondary group was similar to that in the primary group. Thus, endoscopic subureteral glutaraldehyde cross-linked collagen injection is useful for treating complicated secondary vesicoureteral reflux as a minimally invasive procedure. It is considered optional treatment of primary vesicoureteral reflux to avoid long-term prophylactic treatment.

Anterior urethral valves in children : A possible association between anterior urethral valves and Cowper's duct cyst

Abstract:  To elucidate the pathophysiology of congenital obstruction of the anterior urethra and to investigate the association between anterior urethral valves and syringocele. Three boys with congenital obstruction of the anterior urethra diagnosed at our department between 1997 and 2004 were analyzed retrospectively. All three boys had congenital obstruction in the bulbar urethra. The presenting symptoms and age of each patient were varied. Whereas continuity between Cowper’s duct and the diverticulum was not demonstrated radiographically in all of the boys, it was speculated endoscopically in all. Our series has suggested a possible association between anterior urethral valves (diverticulum) and syringocele. These congenital anomalies of the anterior urethra should be considered in the differential diagnosis of obstructive lesions of the urinary tract.

EVALUATION OF ANTIBODY CLASS IN RESPONSE TO ENDOSCOPIC SUBURETERAL COLLAGEN INJECTION IN PATIENTS WITH VESICOURETERAL REFLUX

PURPOSE Clinical problems after glutaraldehyde cross-linked collagen injection for vesicoureteral reflux are the appearance of anticollagen antibodies and a decrease in collagen with time. We evaluated whether antibody production affects reflux recurrence and implanted collagen absorption. MATERIALS AND METHODS We treated 27 patients (39 ureters) who had vesicoureteral reflux with endoscopic subureteral glutaraldehyde cross-linked collagen injection. The maximum diameter of the elevated ureteral orifice was measured 3-dimensionally and the numerical value calculated by multiplying each diameter by approximately pi/6 was used as the ultrasound estimate of injected collagen volume. The 1-to-6-month collagen volume ratio was used as an index of the decrease in implant collagen volume. The antibody class against bovine collagen was characterized by indirect enzyme-linked immunosorbent assay. RESULTS Seroconversion in 6 patients was noted a mean 6.8 months after the first injection. In these patients the antibody class was IgG dominant and IgA or IgM was not detected. There was no significant difference in the total injected collagen volume, total number of injections or collagen volume ratio in the seropositive and seronegative groups. Reflux recurred in 4 patients and the curve of the reflux-free rate was similar regardless of antibody appearance. CONCLUSIONS The immune response to bovine collagen injection for vesicoureteral reflux does not depend on injected collagen volume or an increased number of treatments. Antibody production had no effects on absorption of the implanted collagen or reflux recurrence.