Elijah O. Kehinde

Mutations in 12 known dominant disease-causing genes clarify many congenital anomalies of the kidney and urinary tract

Congenital anomalies of the kidney and urinary tract (CAKUT) account for approximately half of children with chronic kidney disease. CAKUT can be caused by monogenic mutations, however, data are lacking on their frequency. Genetic diagnosis has been hampered by genetic heterogeneity and lack of genotype-phenotype correlation. To determine the percentage of cases with CAKUT that can be explained by mutations in known CAKUT genes, we analyzed the coding exons of the 17 known dominant CAKUT-causing genes in a cohort of 749 individuals from 650 families with CAKUT. The most common phenotypes in this CAKUT cohort were 288 with vesicoureteral reflux, 120 with renal hypodysplasia and 90 with unilateral renal agenesis. We identified 37 different heterozygous mutations (33 novel) in 12 of the 17 known genes in 47 patients from 41 of the 650 families (6.3%). These mutations include (number of families): BMP7 (1), CDC5L (1), CHD1L (5), EYA1 (3), GATA3 (2), HNF1B (6), PAX2 (5), RET (3), ROBO2 (4), SALL1 (9), SIX2 (1), and SIX5 (1). Furthermore, several mutations previously reported to be disease-causing are most likely benign variants. Thus, in a large cohort over 6% of families with isolated CAKUT are caused by a mutation in 12 of 17 dominant CAKUT genes. Our report represents one of the most in-depth diagnostic studies of monogenic causes of isolated CAKUT in children.

Indications of the mechanisms involved in improved sperm parameters by zinc therapy.

Objective: To determine possible indications of the mechanisms involved in improved sperm parameters by zinc therapy in asthenozoospermic men. Subjects and Methods: Forty-five men with asthenozoospermia (≧40% immotile sperm) were randomized into four therapy groups: zinc only: n = 11; zinc + vitamin E: n = 12 and zinc + vitamins E + C: n = 14 for 3 months, and non-therapy control group: n = 8. Semen analysis was done according to WHO guidelines. Malone dialdehyde, tumour necrosis factor-α (TNF-α), total antioxidant capacity, superoxide dismutase (SOD) and glutathione peroxidase were determined in the semen and serum. Antisperm antibodies IgG, IgM and IgA were evaluated by immunobeads. Sperm chromatin integrity was determined by acid denaturation by acridine orange and sperm apoptosis by light and electron microscopy. The effect of zinc on in vitro induced sperm oxidative stress by NADH was evaluated. Results: Asthenozoospermia was significantly associated with oxidative stress with higher seminal malone dialdehyde (8.8 vs. 1.8 mmol/l, p < 0.001) and TNF-α (60 vs. 12 pg/l, p < 0.001), and low total antioxidant capacity (1.8 vs. 8.4, p < 0.01), SOD (0.8 vs. 3.1, p < 0.01) and glutathione peroxidase (1.6 vs. 4.2, p < 0.05), compared to normozoospermia. Zinc therapy alone, in combination with vitamin E or with vitamin E + C were associated with comparably improved sperm parameters with less oxidative stress, sperm apoptosis and sperm DNA fragmentation index (DFI). On the whole, there was no difference in the outcome measures between zinc only and zinc with vitamin E and combination of vitamins E + C. In the in vitro experiment zinc supplementation resulted in significantly lower DFI (14–29%, p < 0.05) compared to zinc deficiency. Conclusion: Zinc therapy reduces asthenozoospermia through several mechanisms such as prevention of oxidative stress, apoptosis and sperm DNA fragmentation.

Identification of two novel CAKUT-causing genes by massively parallel exon resequencing of candidate genes in patients with unilateral renal agenesis

Congenital abnormalities of the kidney and urinary tract (CAKUT) are the most frequent cause of chronic kidney disease in children, accounting for about half of all cases. Although many forms of CAKUT are likely caused by single-gene defects, mutations in only a few genes have been identified. In order to detect new contributing genes we pooled DNA from 20 individuals to amplify all 313 exons of 30 CAKUT candidate genes by PCR analysis and massively parallel exon resequencing. Mutation carriers were identified by Sanger sequencing. We repeated the analysis with 20 new patients to give a total of 29 with unilateral renal agenesis and 11 with other CAKUT phenotypes. Five heterozygous missense mutations were detected in 2 candidate genes (4 mutations in FRAS1 and 1 in FREM2) not previously implicated in non-syndromic CAKUT in humans. All of these mutations were absent from 96 healthy control individuals and had a PolyPhen score over 1.4, predicting possible damaging effects of the mutation on protein function. Recessive truncating mutations in FRAS1 and FREM2 were known to cause Fraser syndrome in humans and mice; however, a phenotype in heterozygous carriers has not been described. Thus, heterozygous missense mutations in FRAS1 and FREM2 cause non-syndromic CAKUT in humans.

The prevalence and predictors of erectile dysfunction in men with newly diagnosed with type 2 diabetes mellitus

To determine the prevalence of and risk factors for erectile dysfunction (ED) in men newly diagnosed with type 2 diabetes mellitus (DM).

Combined Ciprofloxacin and Amikacin Prophylaxis in the Prevention of Septicemia After Transrectal Ultrasound Guided Biopsy of the Prostate

PURPOSE A steady increase in the incidence of septicemia after prostate biopsy in our unit between 2001 and 2005 prompted us to review our prophylactic antibiotic regimen. We compared the incidence of septicemia in patients undergoing prostate biopsy between 2001 and 2005 when only oral ciprofloxacin was used prophylactically (group 1) to the incidence among patients undergoing biopsy between 2006 and 2010 when a single dose of intravenous amikacin was added to ciprofloxacin (group 2). MATERIALS AND METHODS In group 1 the 300 patients were given 500 mg oral ciprofloxacin twice daily 1 day before and for 2 days after the biopsy while in group 2 the 897 patients, in addition to the ciprofloxacin previously mentioned, received 500 mg intravenous amikacin 30 minutes before the biopsy. Patients admitted to the hospital with septicemia after prostate biopsy had urine and blood culture and sensitivity tests. The number of patients in whom septicemia developed in each group after prostate biopsy and the microorganisms isolated from the urine and blood of such patients were compared using the chi-square test. RESULTS Septicemia was seen in 24 of 300 (8%) and 15 of 897 (1.7%) patients in groups 1 and 2, respectively (p <0.001). In group 1 the rate of septicemia after prostate biopsy was 2.1% and 13% in 2001 and 2005, respectively (p <0.001). In group 2 the rate of septicemia was 1.5% in 2006 and 1.6% in 2010 (p <0.25). Escherichia coli resistant to quinolones was responsible for 33 of 39 (84.6%) septicemic cases. CONCLUSIONS The addition of amikacin to ciprofloxacin prophylaxis significantly reduces the incidence of septicemia after prostate biopsy.

Factors predisposing to urinary tract infection after J ureteral stent insertion

PURPOSE We determined the group of patients most likely to have bacterial infection or colonization of J stents inserted to relieve ureteral obstruction. MATERIALS AND METHODS Midstream urine from 250 consecutive patients who required indwelling J stent insertion obtained before stent insertion and on the day of stent removal was analyzed by microbiological testing. At stent removal 3 to 5 cm. of the stent tip located inside the bladder was also sent for culture. Patient sex, duration of stent insertion and systemic disease, such as diabetes mellitus, chronic renal failure or diabetic nephropathy, were recorded. Patients without systemic disease were classified as normal. The rates of bacteriuria, stent colonization and symptomatic urinary tract infection were compared in patients with and without systemic disease. RESULTS Of the 250 patients studied 180 (72%) were men and 70 (28%) were women, while 152 (60.8%) had no systemic disease, 27 (10.8%) had diabetes mellitus, 53 (21.1%) had chronic renal failure and 18 (7.2%) had diabetic nephropathy. The bacteriuria rate was 4.2% for stents removed within 30 days and 34% for stents removed after 90 days (p <0.001). Overall the bacteriuria rate in women was 24.3% compared with 13.9% in men (p <0.06). The rate of bacteriuria in normal patients was significantly lower (3.3%) than in patients with diabetes mellitus, chronic renal failure and diabetic nephropathy (33.3%, 39.6% and 44.4%, respectively, p <0.001). The colonization rate of the tip of the stent was higher in women (64.3%) than in men (34.7%). The stent was removed prematurely in 9 of the 250 patients (3.6%) because of septicemia, including 7 women (77.8%) with systemic disease. CONCLUSIONS The risk of bacteriuria and colonization of the J stent tip is significantly enhanced by the duration of stent retention, patient sex and the systemic disease, such as diabetes mellitus, chronic renal failure and diabetic nephropathy. These categories of patients should undergo shorter stent retention, antimicrobial prophylaxis and careful followup to minimize infectious complications.

Mild Recessive Mutations in Six Fraser Syndrome–Related Genes Cause Isolated Congenital Anomalies of the Kidney and Urinary Tract

Congenital anomalies of the kidney and urinary tract (CAKUT) account for approximately 40% of children with ESRD in the United States. Hitherto, mutations in 23 genes have been described as causing autosomal dominant isolated CAKUT in humans. However, >90% of cases of isolated CAKUT still remain without a molecular diagnosis. Here, we hypothesized that genes mutated in recessive mouse models with the specific CAKUT phenotype of unilateral renal agenesis may also be mutated in humans with isolated CAKUT. We applied next-generation sequencing technology for targeted exon sequencing of 12 recessive murine candidate genes in 574 individuals with isolated CAKUT from 590 families. In 15 of 590 families, we identified recessive mutations in the genes FRAS1, FREM2, GRIP1, FREM1, ITGA8, and GREM1, all of which function in the interaction of the ureteric bud and the metanephric mesenchyme. We show that isolated CAKUT may be caused partially by mutations in recessive genes. Our results also indicate that biallelic missense mutations in the Fraser/MOTA/BNAR spectrum genes cause isolated CAKUT, whereas truncating mutations are found in the multiorgan form of Fraser syndrome. The newly identified recessive biallelic mutations in these six genes represent the molecular cause of isolated CAKUT in 2.5% of the 590 affected families in this study.

Outcome of Endoscopic Treatment for Vesicoureteral Reflux in Children Using Polydimethylsiloxane

PURPOSE We reviewed the outcome of subureteral injection of polydimethylsiloxane as a bulking agent for endoscopic treatment for vesicoureteral reflux in patients younger than 12 years. MATERIALS AND METHODS A total of 40 children (59 ureters) with primary grades II to IV vesicoureteral reflux were treated with a single subureteral injection from 1997 to 2001 and followed an average of 26 months (range 4 to 45). Results in 38 patients (55 ureteral units) were available for review. Each child underwent preoperative voiding cystourethrography, renal ultrasound, dimercapto-succinic acid scan and urine culture. Treatment was done on an outpatient basis. With the patient general anesthesia polydimethylsiloxane implant was injected transurethrally below the ureteral opening of the affected renal unit. Renal ultrasound at 1 week and voiding cystourethrography at 2 months were done to rule out obstruction at the injection site and/or persistent reflux, respectively. Cure was defined as absent vesicoureteral reflux on voiding cystourethrography 2 months after injection. RESULTS After a single injection polydimethylsiloxane cured vesicoureteral reflux in 45 ureteral units (81.8%), while in 5 (9.1%) the condition was improved. The remaining 5 ureteral units (9.1%) showed no change in reflux grade. In 1 patient (1.9%) with unilateral grade IV vesicoureteral reflux contralateral reflux developed. None of the cured patients had recurrent reflux during followup. In 1 patient ureteral obstruction was successfully treated with ureteral reimplantation. CONCLUSIONS Endoscopic subureteral injection of polydimethylsiloxane implant in children with primary grades II to IV vesicoureteral reflux appears to be an effective, safe and minimally invasive technique.

Severe emphysematous pyelonephritis in diabetic patients: diagnosis and aspects of surgical management.

Purpose: Emphysematous pyelonephritis (EPN) is a rare, severe gas-forming infection of renal parenchyma and surrounding tissues seen mostly in diabetic patients. Diagnosis and adequate therapeutic regimen are controversial. We reviewed the clinical presentation, diagnosis and aspects of surgical management of patients presenting with severe EPN. Patients and Methods: Patients with EPN managed in our unit between 1996 and 2004 were reviewed. Diagnosis was confirmed by CT scan appearance of gas in the renal or perirenal area in a very ill patient. We compared the outcome of immediate nephrectomy with drainage of perinephric abscesses in patients presenting with severe EPN. Results: Seven patients were managed in our unit during the 8-year period. All patients were diabetic and women outnumbered men (6:1). Renogram in all 7 patients showed renal function of affected kidney to be less than 15% in 6 patients. Escherichia coli was isolated in all patients from either urine, blood or perinephric pus. Management consisted of intensive resuscitation, control of blood glucose and use of intravenous antibiotics. Emergency nephrectomy was performed in 3 patients, delayed nephrectomy after an initial period of percutaneous drainage in 2 patients, incision and drainage in one patient and immediate percutaneous drainage was performed in one patient. One patient died 5 days post-nephrectomy of myocardial infarction. Patients who had immediate nephrectomy recovered quicker (18–21 days) and had no postoperative complications. Patients who had incision and drainage, or percutaneous drainage presented with recurrent discharging sinuses or perinephric abscesses requiring further surgical interventions and spent longer time in hospital (28–37 days). Conclusion: Patients with severe EPN often present in extremis and require intensive medical treatment. The diagnosis must be entertained in diabetic women presenting with flank pain and septicemia. The function of the affected kidney is often very poor and early nephrectomy offers the best outcome. Percutaneous drainage or incision and drainage of the abscess may be performed in patients too ill for immediate formal nephrectomy.

Allopurinol provides long-term protection for experimentally induced testicular torsion in a rabbit model

To assess the effect of five antioxidants on exocrine function of rabbit testes retained in situ for 24 h and 3 months after experimental torsion.