PubMed Health⌕ Search

Biomedical subjects

M W Burns

Publications and source records attributed to M W Burns.

At least 19 recordsLinked to original sources

Kidney transplantation in children with urinary diversion or bladder augmentation.

PURPOSE: Urinary tract anomalies or dysfunction leaves the bladder unsuitable for urine drainage in a significant proportion of children presenting for kidney transplantation. We reviewed a multi-institutional experience to determine the ramifications of kidney transplantation in children with bladder augmentation or urinary diversion. MATERIALS AND METHODS: During a 28-year period 18 boys and 12 girls 1.7 to 18 years old (mean age 12.1) received 31 kidney transplants. Cause of end stage renal disease was renal dysplasia in 8 cases, posterior urethral valves in 5, obstructive uropathy in 5, neurogenic bladder/chronic pyelonephritis in 4, spina bifida/chronic pyelonephritis in 3, prune belly syndrome in 3 and reflux in 2. RESULTS: Of the patients 17 had augmented bladder (ileum 9, ureter 5, sigmoid 2 and stomach 1), 12 had incontinent urinary conduits (8 ileum, 6 colon) and 1 had a continent urinary reservoir. Surgical complications included 1 case each of stomal stenosis, stomal prolapse, renal artery stenosis, urine leak, enterovesical fistula and wound dehiscence. Medical complications included urinary tract infection in 21 cases and metabolic acidosis in 5. A bladder stone developed in 1 patient. There was no correlation between the incidence of symptomatic urinary tract infections and type of urinary drainage. Acidosis was more common in patients with augmented bladder (4 of 17 versus 1 of 14) but there was no correlation between the bowel segment used and the occurrence of acidosis. Graft survival was 90% at 1 year, 78% at 5 years and 60% at 10 years. Etiology of graft loss included chronic rejection in 6 cases, noncompliance in 4 and acute rejection in 1. There were no deaths. CONCLUSIONS: Drainage of transplanted kidneys into an augmented bladder or urinary conduit is an appropriate management strategy when the native bladder is unsuitable or absent. Patients with kidney transplants drained into augmented bladder or urinary conduit are at increased risk for urine infection. Graft survival is not adversely affected compared to historical controls when a kidney transplant is drained into a urinary conduit or augmented bladder.

Adolescent↗

Voiding dysfunction after bilateral extravesical ureteral reimplantation.

PURPOSE: Voiding dysfunction has been reported after bilateral extravesical ureteral reimplantation. We evaluate the incidence and duration of voiding dysfunction, and the effects of minimizing surgical dissection in a cohort of children after bilateral extravesical reimplantation. MATERIALS AND METHODS: A retrospective chart review was performed on 33 consecutive children who underwent bilateral extravesical ureteral reimplantation for reflux. Preoperative and postoperative radiological studies, and postoperative post-void residuals were reviewed. Of the 33 patients 11 underwent ureteroneocystostomy using a modified Lich-Gregoir technique with ureteral advancement and 22 underwent a modified procedure in which the detrusor dissection was minimized and the obliterated umbilical artery was preserved. Both groups had similar preoperative characteristics. Postoperative surgical success and signs of voiding dysfunction were evaluated and compared between groups. RESULTS: The average length of time until patients were able to void at least half of the bladder volume was 5.9 +/- 3.1 days. The average length of time until successful postoperative Foley catheter or suprapubic tube removal was 7.4 +/- 4.2 days. All children were able to void adequately eventually. Postoperative voiding cystourethrogram demonstrated that reflux was cured in 97% of the ureters. There was no postoperative vesicoureteral obstruction. There was no significant difference in length of time necessary to void, the duration of catheterization or operative success between the children who underwent standard versus limited detrusor dissection procedures. CONCLUSIONS: Extravesical ureteral reimplantation is an effective method for repairing reflux without ureteral obstruction but it can also result in a high rate of transient postoperative urinary retention even when detrusor dissection is minimized.

Adolescent↗

Lower urinary tract changes after early valve ablation in neonates and infants: is early diversion warranted?

PURPOSE: Severe hydronephrosis, high grade reflux and/or renal insufficiency often leads to proximal urinary tract diversion in male infants with posterior urethral valves. Even with this treatment progressive loss of renal function often occurs. Unfortunately with early diversion the bladder, already damaged by in utero obstruction, is also defunctionalized. Alternative treatment with valve ablation in the newborn period and without diversion may facilitate recovery of normal bladder function. MATERIALS AND METHODS: We retrospectively reviewed the records of infants treated for posterior urethral valves before age 1 year at our institution in the last 8 years. Treatment comprised primary valve ablation in 23 patients and urinary diversion in 8. Preoperative and serial postoperative voiding cystourethrograms were scored for degree of trabeculation, bladder neck hypertrophy and prostatic urethral dilatation in all patients undergoing primary valve ablation. Recovery of bladder and renal function after primary valve ablation was compared to that of patients treated with urinary diversion. RESULTS: All patients treated with primary valve ablation demonstrated marked improvement or resolution of bladder abnormalities on voiding cystourethrography by 1 year postoperatively. Bladder compliance and volume were statistically better than in patients treated with primary diversion. Upper tract diversion failed to halt progressive renal failure in 5 of the 6 patients who underwent diversion. Similarly primary valve ablation did not stop progressive renal failure in a matched group of patients. CONCLUSIONS: Early ablation of posterior urethral valves results in the recovery of normal bladder appearance and function when performed in the first months of life. Severe renal insufficiency tends to progress even with upper tract diversion. Furthermore, this treatment prevents normal bladder cycling, which may inhibit bladder recovery in the patient with posterior urethral valves.

Humans↗

Interstitial cystitis in children.

PURPOSE: Interstitial cystitis has been rarely reported in children. We present our experience with 16 children in whom clinical symptomatology and cystoscopic findings were consistent with the diagnosis of interstitial cystitis. MATERIALS AND METHODS: We retrospectively reviewed the charts of 20 children referred for chronic sensory urgency, frequency and bladder pain who underwent cystoscopy and hydrodistension. Four patients were excluded from study because of infection identified at cystoscopy or lack of cystoscopic changes with hydro-distension. RESULTS: Patient age at onset of first symptoms ranged from 2 to 11 years (median 4.5) and age at diagnosis ranged from 3 to 16 years (mean 8.2). Of the 16 children 14 (88%) presented with symptoms of urinary frequency and sensory urgency, and in 13 (81%) lower abdominal pain was relieved by voiding. None of the children had motor urgency. Urodynamic evaluation in 8 cases revealed early bladder sensation with no evidence of involuntary bladder contractions. Diffuse glomerulations and terminal hematuria were demonstrated in all patients after hydro-distension. Followup was available for 14 patients. Relief of symptoms occurred after hydro-distension in all children except 1. Seven children (50%) required repeat hydro-distension. CONCLUSIONS: Children with symptoms of bladder pain, urinary frequency and sensory urgency have bladder changes on cystoscopy consistent with interstitial cystitis. Although rare, this condition is recognizable and it should not be confused with dysfunctional voiding in which complaints are secondary to involuntary bladder contractions.

Adolescent↗

Chronic cough. Diagnostic and management options.

Chronic cough is divided into productive and non-productive presentations. The various causes of each are reviewed and a management approach offered. It is emphasized that a cough lasting more than a few weeks merits investigation. The article concludes with a summary of the appropriate investigations available to assist in diagnosing the cause of this troublesome and difficult problem.

Anti-Bacterial Agents↗

Pseudoureterocele: potential for misdiagnosis of an ectopic ureter as a ureterocele.

OBJECTIVE: To present several case reports of children with 'pseudoureteroceles'. Familiarization with this entity should help to avoid an error in diagnosis and possible improper therapy. PATIENTS AND METHODS: Three girls with ectopic ureters entering mesonephric duct cysts are presented for review. RESULTS: Misdiagnosis of the pseudoureterocele as an ectopic ureter was made in two children. The 'pseudoureterocele' may lie dormant for many years and often presents with acute urinary incontinence and/or onset of urinary tract infections. Resection of the dysplastic kidney and ipsilateral ureter, marsupialization of the cyst into the vagina, and closure of the vesical fistula is the preferred treatment. CONCLUSION: An ectopic ureter draining into a Gartner's duct cyst can be confused with an ectopic ureterocele. Correct diagnosis is vital to ensure proper treatment.

Adolescent↗

Renal transplantation into the dysfunctional bladder: the role of adjunctive bladder reconstruction.

A retrospective review of pediatric renal transplantation at 3 centers identified 9 patients who had undergone major bladder reconstruction. Seven patients underwent bladder augmentation (5 gastric, 1 colonic, 1 ureteral) and 2 received gastric neobladders. Six patients required Mitrofanoff neourethras. Patient survival was 100% with initial graft survival of 56% during a mean followup of 29.4 months. Eight patients (89%) are presently dialysis-free with functioning allografts and all 9 (100%) are continent of urine. We conclude that renal transplantation and reconstruction to ensure continence are justifiable in even the most anatomically compromised children with end stage renal disease. It is essential that the pediatric urologist should have an integral role in the management of such cases.

Adult↗

Aggressive surgical and medical management of autosomal recessive polycystic kidney disease.

The treatment of autosomal recessive polycystic kidney disease (ARPKD) is evolving. Overall prognosis is difficult to determine, but most neonates without severe pulmonary hypoplasia will survive. It is difficult to predict which neonates with ARPKD requiring immediate ventilatory support have pulmonary hypoplasia incompatible with survival. Massively enlarged kidneys restricting diaphragmatic excursion can cause respiratory distress in addition to pulmonary hypoplasia. Three infants with ARPKD underwent bilateral nephrectomies and institution of peritoneal dialysis in an attempt to improve ventilatory status and assess long-term pulmonary function. Two children are alive at twelve and thirty months postoperatively and awaiting renal transplantation. One infant died of acute cardiorespiratory complications.

Child, Preschool↗

The syndrome of dysuria and hematuria in pediatric urinary reconstruction with stomach.

Between July 1989 and March 1992 at a single institution 27 male and 30 female patients underwent lower urinary reconstruction with stomach. Mean patient age was 9.9 years (range 1.5 to 28 years). The diagnoses were epispadias/exstrophy complex (19 patients), myelodysplasia (11), cloacal exstrophy (6), posterior urethral valves (6), Hinman syndrome (4), sacral agenesis (3) and other (8). Indications for surgery were urinary incontinence, upper tract deterioration or undiversion. A total of 54 patients underwent augmentation gastrocystoplasty and 3 had total bladder replacement. Mean followup time was 23.2 months (range 12 to 39 months). The syndrome of dysuria and hematuria is defined as 1 or a combination of the following symptoms: bladder spasm or suprapubic, penile or periurethral pain, coffee brown or bright red hematuria without infections, skin irritation or excoriation and dysuria without infections. Telephone and clinic interviews identified 21 patients (36%) with symptoms of the dysuria and hematuria syndrome. The most common symptoms were hematuria (71%) and bladder or suprapubic pain (76%). Of the patients 18 (86%) ranked the severity of symptoms as mild to moderate and 3 (14%) ranked them as severe. No medications were required to control the symptoms in 13 patients (62%) and 3 other patients only required medications on an as needed basis. Overall patients who required no medications had lower symptom scores than those who required medications. Patients with decreased renal function may be more at risk for the dysuria and hematuria syndrome than those with normal renal function. Patients who were wet were more prone to have the dysuria and hematuria syndrome than those who were totally dry. The pathophysiology of the dysuria and hematuria syndrome is currently unknown. Patients who require urinary reconstruction with stomach tissue need to be made aware of the potential of the dysuria and hematuria syndrome.

Adolescent↗

The use of the AMS800 artificial urinary sphincter in combination with the gastric tube for continence in the canine model.

An experimental canine model was designed to examine the potential use of the artificial urinary sphincter around a gastric tube. The artificial urinary sphincter was placed around a tubularized gastric flap as part of a continent gastric reservoir in 4 dogs and in 2 additional dogs the gastric tube was anastomosed to the native bladder. Two dogs underwent placement of the artificial urinary sphincter around the gastric tube 4 weeks postoperatively and the remainder had the sphincter placed simultaneously with creation of the gastric tube. All dogs with the gastric reservoir underwent urodynamics before and after activation of the sphincter. Only 61 to 70 cm. water pressure balloons were used. All dogs were continent postoperatively on clean intermittent catheterization every 8 hours. There were no erosions or problems with catheterization. Urodynamics confirmed a complaint system and an average increase of capacity of 410% after artificial urinary sphincter activation (4 dogs). There was no leakage at capacity. Histology of the artificial urinary sphincter and neighboring (control) regions, and of the reservoir at 1 (2 dogs), 3 (3 dogs) and 6 months (1 dog) was obtained. Microscopic examination of the cuff site showed mild serosal hyperplasia and fibrosis, a well preserved muscularis and mild to moderate focal mucosal atrophy. These changes were slightly more evident at 6 months. Mucosal folds were well preserved with normal submucosa and lamina propria. In the control region histology was well preserved and similar to native stomach. We conclude that the artificial urinary sphincter around a gastric tube can provide urinary continence. The minimal changes in histology under the cuff are encouraging and support the potential for use of the gastric tube with the artificial urinary sphincter, although longer term effects are unknown.

Animals↗

The Mitrofanoff principle in urinary reconstruction.

We report the use of the Mitrofanoff principle to achieve urinary continence in 47 patients. A catheterizable channel can be used as the primary continence mechanism, or as an adjunct to ensure complete bladder emptying if urethral catheterization or voiding is inadequate. Appendico-vesicostomy was performed in 25 of 47 patients (55%). Satisfactory continence was achieved in 45 patients (96%). Bladder emptying by clean intermittent catheterization was performed in all patients. Early complications included peristomal abscess (1 patient) and small bowel obstruction (1). Late complications included difficulty with catheterization (5 patients), stomal stenosis (9) and persistent incontinence (2). Our results support use of the appendix as the catheterizable segment of choice. We describe the technique and discuss the management of complications.

Appendix↗

Lower urinary tract reconstruction using stomach and the artificial sphincter.

We implanted the artificial urinary sphincter at gastrocystoplasty in 13 male and 5 female patients. The diagnoses were classical bladder exstrophy (8 patients), myelodysplasia (8), cloacal exstrophy (1) and bilateral ectopic ureters (1). Mean patient age was 14.3 years (range 7 to 32.5). Six patients (5 with bladder exstrophy and 1 with clocal exstrophy) had failed bladder neck continence procedures, 3 myelodysplastic patients had failed artificial urinary sphincter placement, and 1 exstrophy patient had failed a Young-Dees bladder neck repair and artificial urinary sphincter placement. The sphincter cuff was placed around the reconstructed bladder neck in these patients, while in the remainder the artificial urinary sphincter was placed around the intact bladder neck. Mean followup was 20.3 months (range 1 to 5). Of the patients 16 (88%) are continent day and night, while 2 are wet. A total of 11 patients (61%) use Valsalva's maneuver alone for voiding and the remainder use Valsalva's maneuver and/or clean intermittent catheterization for bladder evacuation. Complications related to the artificial urinary sphincter were recurrent pump erosion requiring conversion to a Mitrofanoff continent stoma in 1 patient, and mechanical dysfunction requiring pump cuff and reservoir replacement in 3. There were no complications due to infection. Our report demonstrates that the combination of augmentation gastrocystoplasty and an artificial urinary sphincter leads to urinary continence and can allow for spontaneous urination. The rate of infectious complications is not increased when the 2 procedures are combined simultaneously.

Adolescent↗

Treatment of bladder dysfunction in children with end-stage renal disease.

The appropriate management of the urinary bladder in patients requiring a renal transplant is significantly different in children than in adults. The etiology of end-stage renal disease (ESRD) in 13 of 50 children (26%) transplanted since 1985 was obstructive uropathy/dysplasia. Five of these children had small-capacity, poorly compliant bladders. Our current approach is to restore bladder compliance, improve emptying, and transplant into the restored bladder rather than divert. Pretransplant gastrocystoplasty was performed in three children and the donor ureter was implanted into the augmented bladder. One child awaits transplantation following his bladder augmentation. Bladder function is followed postoperatively by voiding cystourethrography (VCUG) and urodynamics. All of the children who have received transplants into augmented bladders are infection-free, voiding per urethra, and have functioning allografts. We recommend: (1) an initial VCUG in all children; (2) complete urodynamics, if appropriate; (3) urological reconstruction to include augmentation prior to transplantation; (4) transplantation into the reconstructed bladder; and (5) comprehensive follow-up including regular urodynamic assessment.

Adolescent↗

Glomerular cell proliferation and PDGF expression precede glomerulosclerosis in the remnant kidney model.

Increasing evidence supports a role of glomerular cell proliferation in the development of focal or diffuse glomerulosclerosis. This study investigates the chronology and sequence of cellular events that precede glomerulosclerosis in 5/6 nephrectomized rats. Within three days of renal ablation, a phenotypic switch occurred in which some mesangial cells expressed alpha-smooth muscle actin. This was followed by proliferation of mesangial cells, and to a lesser degree endothelial cells from day 5 to week 4 as detected by immunostaining for the proliferating cell nuclear antigen (PCNA). Glomerular cell proliferation was accompanied by increased immunohistochemical expression of PDGF B-chain. In situ hybridization showed no glomerular PDGF B-chain mRNA expression at the induction of proliferation (day 5), and a marked increase between week 1 and 4 in operated rats. In parallel, increased expression of PDGF receptor beta-subunit protein and mRNA was demonstrated by immunohistochemistry and Northern analysis of total glomerular RNA. The onset of glomerular cell proliferation was also associated with mild glomerular platelet accumulation (as defined by 111In-labelled platelet studies) as well as with fibrinogen deposition. Proteinuria, glomerular sclerotic changes, and leukocyte infiltration all followed cell proliferation. The glomerular leukocyte infiltrate consisted of monocytes/macrophages and increased markedly at week 10 in rats with renal ablation. Thus, our results suggest that in the remnant kidney model: 1) proliferation of intrinsic glomerular cells precedes glomerulosclerosis; 2) proliferation may be initiated by degranulating platelets and sustained by PDGF released from intrinsic glomerular cells; and 3) glomerular monocyte/macrophage infiltration occurs after the proliferation, and may possibly contribute to the development of glomerular sclerotic changes.

Actins↗

Glomerular cells, extracellular matrix accumulation, and the development of glomerulosclerosis in the remnant kidney model.

Expansion of the mesangial extracellular matrix (ECM) with subsequent glomerular sclerosis is a prominent finding in most progressive renal diseases. To investigate the chronology of accumulation of ECM components as it relates to previously described cellular events, biopsies were obtained from rats at various times following 5/6-nephrectomy as well as from sham-operated controls. The biopsies were stained with PAS as well as immunostained for PCNA (a cell proliferation marker), monocytes/macrophages, types I and IV collagen, laminin, s-laminin, fibronectin, heparan sulfate proteoglycan and entactin/nidogen. Immunostaining of biopsies obtained from 5/6 nephrectomized rats demonstrated an early glomerular cell proliferation, peaking at week 2. Expansion of the glomerular tuft area with rare glomeruli demonstrating focal sclerosis were also seen at week 2. Glomerular macrophage influx correlated with later ECM expansion and glomerulosclerosis. A progressive accumulation of all ECM proteins investigated was noted in the pathological mesangial matrix at week 2 and later time points. Northern analysis of total glomerular RNA at weeks 2 and 6 after 5/6 nephrectomy showed de novo expression type I collagen mRNA as well as small increases of glomerular mRNA levels for type IV collagen (1.2- and 1.4-fold over control RNA) and laminin (1.3- and 1.5-fold) but not s-laminin (1.1- and 0.9-fold). We conclude that cellular events including glomerular cell proliferation and macrophage influx are associated with increased gene and protein expression by ECM proteins in the remnant kidney model and may contribute to the development of sclerosis.

Animals↗

Intraoperative cardiovascular collapse secondary to latex allergy.

An apparent allergic reaction has been noted in children undergoing open urological surgery. This condition is characterized by precipitous hypotension, tachycardia and upper body flushing, and it often causes termination of the procedure. Latex allergy has been identified as the possible inciting event. Contact of latex rubber gloves with intra-abdominal structures (handling bowel) appears to be the most dramatic trigger mechanism for this reaction. We report on 10 patients with latex allergy, 6 of whom have myelomeningocele, who have undergone reconstructive surgery. Severe anaphylactic shock developed intraoperatively in 5 patients and during a barium enema performed with a latex catheter in 1 patient. These 6 patients had previous allergic reactions to latex material, which was not detected preoperatively. In the remaining 4 patients latex allergy was diagnosed preoperatively. A total of 6 patients agreed to a skin prick test to liquid latex. Three patients reacted with a wheal size greater than or equal to a histamine control at a dilution of 1:1,000 and 3 patients at 1:100. In contrast, none of the 5 normal controls reacted to any of the concentrations including full strength latex. A history of exposure to latex products (balloons, surgical gloves, catheters, condoms and so forth) with allergic reactions should heighten surgeon awareness of a potentially severe intraoperative reaction. Furthermore, a skin prick test may be used to screen high risk patients such as those with myelomeningocele. A protocol involving preoperative corticosteroid and antihistamine therapy is recommended.

Adolescent↗

Glomerular subendothelial and subepithelial immune complexes, containing the same antigen, are removed at different rates.

To examine the persistence of immune deposits in the subendothelial and subepithelial areas of the glomerular basement membrane in rats, immune deposits were formed by injection of radiolabelled, cationized human serum albumin (HSA) as antigen, followed by rabbit antibodies to HSA. The disappearance of the radiolabelled antigen from immune deposits in glomeruli was described by a curve consisting of two exponential components. By electron microscopy, subendothelial and subepithelial immune deposits were initially present in glomeruli. At later time-points, only subepithelial immune deposits were present. The fast component of disappearance, attributed to subendothelial deposits, had a half-life of 3.89 +/- 0.32 h. The slow component of disappearance from glomeruli, attributed to subepithelial deposits, had a half-life of 85.5 +/- 3.1 h. Since some of the injected, radiolabelled antigen was sequestered in other compartments of the body, the possibility was raised that antigen from these sites might be released and contribute to the persistence of deposits in glomeruli. This possibility, however, was excluded when transplantation of kidneys with immune deposits to untreated recipients revealed no difference in the amount of antigen persisting in nontransplanted and transplanted kidneys.

Animals↗