Biomedical subjects

P G Duffy

Publications and source records attributed to P G Duffy.

18 recordsLinked to original sources

PubMed1992

Cadaveric renal transplantation in children under 5 years of age.

From March 1987 to August 1990 23 cadaveric renal transplants were performed in 19 children under the age of 5 years at the time of transplantation. The mean age of the recipients was 3.3 years (range 1.3-4.7) and the mean weight 13.0 kg (range 9.3-19.2). The mean donor age was 7.8 years (range 1.5-25). All children received triple immunosuppression with prednisolone, cyclosporin A and azathioprine, and 4 who had 2 grafts during this period also received antithymocyte globulin at the time of the second transplant. Patient survival is 100%. Actuarial first cadaveric graft survival was 57% at 1 year and remains unchanged at 3 years. There were 10 graft losses, 4 were associated with renal venous thrombosis without apparent rejection. Two were lost due to acute vascular rejection with associated renal venous thrombosis, and the remaining 4 losses followed cellular or chronic vascular rejection. The mean glomerular filtration rate +/- SD was 51.4 +/- 23.6 ml/min per 1.73 m2 (n = 11) at 1 year and 43.5 +/- 25.3 at 2 years (n = 6). The mean height standard deviation score improved from -2.2 +/- 1.1 at the time of transplantation to -1.3 +/- 1.0 1 year post transplant (n = 11). The immunosuppression was well tolerated with a low incidence of side effects. Cadaveric renal transplantation remains a difficult but rewarding undertaking in children under 5 years of age.

Age Factors↗

PubMed1992

Lower urinary tract function after exstrophy closure.

Twenty-eight children with bladder exstrophy, prior to surgery for continence, underwent a urodynamic evaluation, cystogram, ultrasound and dimercaptosuccinic acid scan, to define parameters of lower urinary tract function that are a risk for upper tract damage and/or impair development of bladder capacity. The bladders in 7 of 28 demonstrated no storage function [leak pressure)LP) = 0]; but storage parameters could be measured in the other 21. Their LP was 10-35 cm H2O; 17 of 21 revealed involuntary contractions and 7 of 21 had an end-fill pressure greater than 10 cm H2O. Bladder capacity was better in those with a higher LP and those with no involuntary contractions. The 4 patients with bilateral hydronephrosis (3 of whom also had bilateral multiple scars) were among the 6 with LP greater than 30 cm H2O. Of the 7 with an end-fill pressure greater than 10 cm H2O, 5 had upper tract damage. Involuntary contractions may impair development of capacity. A LP of greater than 30 cm H2O is a risk factor for upper tract damage and an end-fill pressure greater than 10 cm H2O may also be a factor.

Bladder Exstrophy↗

PubMed1992

Delayed linear growth in children with enterocystoplasties.

A series of 60 children whose urine was stored in pouches formed in whole or in part from bowel were reviewed to establish the effect on growth in height and weight. The mean age at operation was 7.8 years (range 0.9-14.1). Patients were included only if there were at least 2 measurements of both parameters pre-operatively and 2 post-operatively over a minimum follow-up of 2.5 years. Delayed growth in height alone occurred in 12 children (20%), with a mean loss of 25 percentile points (range 10-50). Delayed growth in height and weight occurred in 4. Accelerated growth in height alone, weight alone and in both occurred in 2, 7 and 7 respectively. There was no difference in a wide range of laboratory data between any of these groups. Although changes in growth rate (for better or worse) may occur for a variety of reasons after major surgery, delayed linear growth in isolation is an unusual and worrying finding that suggests a major alteration in bone development.

Body Height↗

PubMed1992

Endoscopic reappraisal of the morphology of congenital obstruction of the posterior urethra.

Congenital obstruction of the posterior urethra was first systematically classified by Young in 1919. Since then, no-one has seriously challenged the presence of both Type I and Type III "valves", although the presence of Type II lesions has often been disputed. A review of Young's papers and more recent anatomical studies, together with endoscopic findings in our own patients, indicates that most congenital posterior urethral obstructions are anatomically similar. Consequently, Young's classification now seems redundant.

Endoscopy↗

PubMed1991

Bladder function and dysfunction in exstrophy and epispadias.

Bladder exstrophy and epispadias are congenital abnormalities of the urinary bladder. Evaluation of bladder function before and after bladder-neck reconstruction has not been done in patients with these conditions. We report the preliminary results of a prospective study of lower-urinary-tract function in 36 children (10 girls, 26 boys; age range 1.5-16 years) with bladder exstrophy and epispadias. Children's bladder function was measured by cystometry and cystography, and their upper urinary tracts were examined by ultrasound imaging. Normal bladder function was seen in children with primary epispadias but this was severely impaired in children who had had conventional bladder-neck surgery for continence, implying that this may not be the optimal treatment. Contrary to current assumption, children with closed exstrophy bladders are not capable of normal function, and the abnormalities we identified may be a major cause of upper-urinary-tract damage and may impair development of bladder capacity. Although unrecognised in the past, involuntary bladder contractions are a primary cause of urine leakage persisting in children with exstrophy and epispadias after continence surgery. Detailed functional testing should become a routine part of the evaluation of children with exstrophy and epispadias.

Adolescent↗

PubMed1991

The use of the Mitrofanoff principle in achieving clean intermittent catheterisation and urinary continence in children.

The Mitrofanoff principle has been used to achieve clean intermittent catheterisation (CIC) and urinary continence in 28 children. The mean age at operation was 10.1 years (range, 1 to 19 years). A catheterisable conduit was created using the appendix (19), ureter (8), or vas deferens (1). CIC was commenced 10 to 28 days postoperatively (median, 15 days). After a mean follow-up of 13 months (range, 2 to 45 months), 24 children (86%) have achieved successful CIC and urinary continence. Use of the Mitrofanoff principle is a valuable adjunct to the treatment of urinary incontinence in children and may allow successful CIC in patients who are unable to catheterise urethrally.

Adolescent↗

PubMed1991

Risks and benefits of percutaneous biopsy and primary chemotherapy in advanced Wilms' tumour.

Between 1982 and 1988, 36 children with advanced Wilms' tumour underwent percutaneous trucut needle biopsy followed by chemotherapy before definitive surgery. Nephrectomy was performed after a median of 14 weeks of chemotherapy. Substantial reduction in tumour bulk was achieved in 94% of patients. Biopsy morbidity was low and complete concordance between the histological assessment of the tumour in the biopsy specimen and at subsequent nephrectomy was confirmed in 26 of 28 (93%) patients. The overall clinical value of trucut biopsy was 83% (30/36 patients). Survival rates in this high-risk group were comparable to those of children with less advanced disease. Chemotherapy may be the primary treatment of choice for patients with Wilms' tumour. Percutaneous biopsy allows definition of histology in most patients without increasing morbidity.

Adolescent↗

PubMed1991

Duplex reflux: a study of 105 children.

A series of 105 children with vesicoureteral reflux into completely duplicated collecting systems was studied retrospectively. Of the children 64% were treated surgically, with two-thirds undergoing an ablative procedure and one-third undergoing common sheath ureteral reimplantation. The remaining 36% of the children were managed nonoperatively and followed for up to 11 years. Among these cases 89% of the kidneys had reflux into the lower pole moiety only and 11% had reflux into the upper and lower pole moieties. The spontaneous rates of reflux resolution were 85% for grades I and II, and 36% for grade III reflux during a median observation period of 40 months. These figures suggest that the spontaneous resolution of mild to moderate reflux into completely duplicated collecting systems is similar to that of identical degrees of single system reflux during a comparable observational period.

Abnormalities, Multiple↗

PubMed1991

Pedicle patch urethroplasty.

The pedicle patch urethroplasty provides an alternative single-stage vascularised graft procedure for the repair of moderately severe hypospadias. Over a 7-year period, 38 primary hypospadias repairs were performed employing this technique. The fistula rate was 18% in the 34 patients reviewed, but there were few other significant complications. The operation is recommended when the urethral plate can be preserved and the penis straightened in boys who are unsuitable for a meatal-based flap.

Age Factors↗

PubMed1991

Blood and urine analysis in patients with intestinal bladders.

A group of 183 patients whose urine was stored in pouches formed either wholly or partly from bowel was reviewed to establish abnormal biochemical and haematological factors and to assess the risk of infection. Minimum follow-up was 1 year (range 1-28.5, mean 3 years 8 months) and the mean age of the patients at follow-up was 16.5 years (range 4-43). Pouches were augmentation and substitution cystoplasties and complete reconstructions with bowel. Bowel segments were ileum (55 patients), colon (100) and mixed (28). Anaemia was found in 15 patients, folate deficiency in 2 and folate excess in 2. Definite hyperchloraemic acidosis was found in 25 patients and borderline results in 40. Most of these patients had colon in the pouch but 5 definite and 13 borderline cases had ileum only. Troublesome urinary infections occurred in 27.9% of patients; 3 developed renal stones and 22 developed pouch/bladder stones. Stones were usually associated with infection and/or staples. Delayed linear growth occurred in 20% of children in spite of a normal increase in weight; there was no difference in any of the measurements between those who grew and those who did not.

Adolescent↗

PubMed1991

Hypospadias: Duckett pedicle tube urethroplasty.

The Duckett transverse tube pedicle urethroplasty was used to repair the primary hypospadias of 190 boys over an 11-year period. The fistula rate was 34.4%. The majority of boys have obtained a satisfactory cosmetic and functional result with a single operation.

Adolescent↗

PubMed1990

The functional sequelae of sacrococcygeal teratoma.

Twenty-seven patients with sacrococcygeal teratoma were followed for a mean period of 5 years (range, 2 to 12 years). Eleven (41%) had some form of functional impairment. Fecal and/or urinary incontinence was present in nine children and two had weakness of the lower limbs secondary to sciatic nerve palsy. Tumors with large intrapelvic extensions requiring an abdominoperineal approach for resection were associated with a higher incidence of functional sequelae (67%). It is recommended that patients with sacrococcygeal teratoma (particularly those with a presacral extension) be closely monitored for functional deficits so that early treatment can be instituted.

Fecal Incontinence↗

PubMed1990

The postnatal management of hydronephrosis diagnosed by prenatal ultrasound.

A total of 112 patients (142 kidneys) presented with hydronephrosis consistent with ureteropelvic junction obstruction that had been diagnosed by prenatal ultrasound. The kidneys were classified as having poor, moderate or good function based on isotope imaging at 3 months after birth. Of 9 kidneys that showed poor function 3 recovered sufficient function on pigtail drainage to justify preservation and these patients underwent pyeloplasty. Of 27 kidneys with moderate function 23 also underwent pyeloplasty and 14 of these demonstrated improvement in function postoperatively. Of the 100 kidneys in the good function group that were followed conservatively 23 underwent pyeloplasty during followup primarily because of an observed decrease in function. We propose that there is no indication for immediate pyeloplasty in infants with prenatally diagnosed hydronephrosis who demonstrate good function postnatally.

Fetal Diseases↗

PubMed1990

Buried penis. A novel approach.

Buried penis is a congenital abnormality in which the phallus is concealed within the subcutaneous tissue. The corporal bodies and glans have developed normally. A deficiency of penile shaft skin in association with abnormal mobility of the skin gives rise to the phenotypic appearance. The skin defect may be related to an abnormal attachment of dartos muscle during embryogenesis. Correction of this condition requires separation of these abnormal muscular attachments and provision of skin coverage of the penile shaft. It is imperative not to circumcise the patient as this will worsen the skin deficiency. We describe a novel technique for correcting buried penis performed on 12 patients at the Great Ormond Street Hospital for Sick Children. A satisfactory cosmetic result was obtained in all patients.

Humans↗

PubMed1989

Congenital mesoblastic nephroma, renin production, and hypertension.

Between 1964 and 1987, 12 patients with mesoblastic nephroma were treated. The BP was measured preoperatively in five patients, four of whom were hypertensive. Following nephrectomy, the BP returned to normal. Plasma renin levels were measured in one patient; they were markedly elevated pre-operatively, but returned to normal following tumour excision. Immunoreactive renin staining, using a polyclonal antibody to human renin, was performed in the 12 patients. Staining was positive in ten patients. The most intense staining was noted in the areas of cortex entrapped within the tumour, and in perivascular spaces not associated with entrapped cortex. These findings suggest that hypertension secondary to increased tumour associated renin production is a feature of congenital mesoblastic nephroma.

Child, Preschool↗

PubMed1989

Priorities in urinary diversion following pyeloplasty.

Debate continues regarding optimal drainage following pyeloplasty. We reviewed the method of drainage in 100 consecutive dismembered pyeloplasties performed from 1983 to 1987. Of the children 20 per cent underwent pyeloplasty with placement of a nephrostomy tube and transanastomotic stent (group 1), while 80 per cent underwent pyeloplasty performed in a nonintubated fashion (group 2). A urethral bladder catheter was used in 20 per cent of the patients in group 1 and in 90 per cent in group 2. While the over-all complication rates and long-term results were similar for both groups, the nature of complications for each group differed. The intubated group had a 10.5 per cent incidence of urinary tract infection, while the nonintubated group demonstrated an 8.6 per cent incidence of postoperative anastomotic leakage. A nephrostomy tube and stent appear to be unnecessary in the routine pyeloplasty and may prolong hospitalization. Selective use of upper tract drainage may help to decrease the incidence of postoperative leakage in specific cases.

Child↗

PubMed1989

Urinary tract obstruction secondary to presacral teratoma: a missed diagnosis.

We describe 2 neonates with bladder outlet obstruction secondary to presacral teratoma. The clinical course and investigations are discussed to illustrate the errors made and difficulties experienced in making this diagnosis. The value of routine rectal examination in all neonates who present with lower urinary tract obstruction is stressed.

Diagnostic Errors↗

PubMed1988

Combined free autologous bladder mucosa/skin tube for urethral reconstruction: an update.

A combined free autologous bladder mucosa/skin graft was used to reconstruct the urethra in 23 patients. Although the complication rate remains high (61%), the results represent a significant improvement over the use of complete mucosal tubes to the tip of the penis. The technique is recommended for those patients with failed hypospadias surgery, where sufficient skin is not available for urethral reconstruction.

Adolescent↗