PubMed Health⌕ Search

Biomedical subjects

M A Koyle

Publications and source records attributed to M A Koyle.

At least 37 records · Page 2Linked to original sources
PubMed1993

Laparoscopic nephrectomy in the first year of life.

A child was found antenatally to have a cystic right kidney on maternal ultrasound. This was evaluated in the immediate postnatal period with imaging studies and confirmed to be a multicystic, dysplastic kidney. Expectant management was followed; however, the kidney was found to be unchanged in size on a 6-month ultrasound and the parents elected surgical removal rather than continued medical surveillance. A nephrectomy was performed using laparoscopic techniques rather than standard open surgery. Operating time was less than 1 hour. The patient's recovery was unremarkable.

Humans↗
PubMed1993

Ventral preputial onlay island flap and proximal flip-flap technique for the repair of epispadias: a case report.

Use of the ventral preputial island flap technique for repair of epispadias has yielded satisfying functional and cosmetic results. We report a modification of this technique in a patient with proximal penile epispadias without exstrophy. We used the Duckett modification of the onlay island flap using ventral preputial skin and coupled it with a proximal flip-flap of perimeatal skin without division of the urethral plate. This achieved an excellent result.

Epispadias↗
PubMed1992

Endopyelotomy associated ureteral necrosis: complete ureteral replacement using the Boari flap.

A case of an adolescent who sustained necrosis of the entire ureter after attempted endopyelotomy for congenital ureteropelvic junction obstruction is presented. Successful reconstruction of a neoureter was performed easily with the Boari bladder flap coupled with nephropexy and a psoas hitch. Although repair of upper ureteral injuries with the Boari flap has been described in the literature, to our knowledge its use in the pediatric population has not. Our case exemplifies how the Boari flap repair is particularly suitable in children for bridging significant segments of injured ureters, not just the lower third.

Adolescent↗
PubMed1992

Extrarenal angiomyolipomas of the perinephric space.

We describe 2 cases of extrarenal angiomyolipoma of the perinephric space. All other cases of extrarenal angiomyolipoma of the retroperitoneum are reviewed and the clinical relevance of this unusual pathological entity is discussed.

Adult↗
PubMed1991

Nephrogenic rests in Wilms tumor patients with the Drash syndrome.

The histological specimens from 12 patients with the Drash syndrome were identified from the National Wilms Tumor Study Group and reviewed for the presence of nephrogenic rests. Of 7 patients with the complete Drash syndrome 6 were evaluable for nephrogenic rests, including 5 (83%) who demonstrated intralobar nephrogenic rests. Of 5 (80%) partial Drash syndrome cases 4 (80%) were also intralobar nephrogenic rest positive. Neither group had perilobar nephrogenic rests identified. In a control population of Wilms tumor patients without the Drash syndrome only 39 of 274 (14%) with unilateral tumor had intralobar nephrogenic rests identified, whereas 26 of 92 (28%) bilateral cases had intralobar nephrogenic rests. There was a significantly higher rate of intralobar nephrogenic rests in complete and partial Drash syndrome cases than in the general Wilms tumor population (p less than 0.001). Wilms tumor patients with intralobar nephrogenic rests and the Drash syndrome present at a younger age and have a higher rate of bilaterality than rest negative Wilms tumor patients. The strong association of intralobar nephrogenic rests in the Drash syndrome approaches that found in the aniridia complex. However, in other syndromes associated with Wilms tumor, such as the Beckwith-Wiedemann syndrome and hemihypertrophy, there is a high prevalence of perilobar nephrogenic rests. In view of the high incidence of intralobar nephrogenic rests in complete and partial Drash syndrome patients, it is probable that events leading to Wilms tumor in patients with the Drash syndrome occur at an early stage in nephrogenesis.

Disorders of Sex Development↗
PubMed1991

The beneficial effect of blood transfusion and the DR 1 gene dose on renal transplant outcome in blacks.

We performed a retrospective analysis of the factors determining renal allograft survival in 70 black recipients from a single center and 1212 black recipients from multicenter registry data. One and two-year graft survival in single-center blacks was comparable to the result achieved in the general population (81% and 77%, respectively). Two-year graft survival in multicenter blacks was significantly worse than nonblacks (73% versus 55%, respectively; P less than 0.01). Graft survival in untransfused blacks receiving cyclosporine was no better than the result achieved during the azathioprine era. A beneficial effect upon graft survival was seen in blacks transplanted at the centers that have consistently displayed the best overall allograft survival over the years. Matching for HLA antigens was consistently poorer in blacks compared with whites and did not confer additive benefit over cyclosporine and blood transfusion. Our data indicate that cyclosporine immunosuppression, blood transfusion, and individual center expertise contribute significantly toward optimal transplant outcome in the higher-risk black end-stage renal disease population.

Age Factors↗
PubMed1990

The necessity of contralateral surgical exploration in Wilms tumor with modern noninvasive imaging technique: a reassessment.

Surgical exploration of the contralateral kidney in unilateral Wilms tumor has been the standard of surgical practice. During the last decade advances in noninvasive imaging techniques (ultrasound, computerized tomography and magnetic resonance imaging) have led to more accurate definition of intrarenal pathological conditions. The intuitive question presently is whether contralateral exploration remains mandatory in Wilms tumor patients. We reviewed the records of 52 consecutive children at our institutions who underwent radiological and operative staging of the Wilms tumor from 1979 to 1988. All 48 evaluable patients underwent either preoperative computerized tomography, ultrasound and/or magnetic resonance imaging. Five bilateral Wilms tumors were diagnosed preoperatively and confirmed surgically, whereas extensive operative exploration of the contralateral kidney in the other 43 cases of radiologically diagnosed unilateral disease failed to reveal any contralateral abnormality. Thus, in all patients preoperative radiological investigation was accurate to stage the disease regarding bilaterality. With modern imaging techniques and effective chemotherapy, extensive contralateral renal exploration may no longer be mandatory to manage Wilms tumor.

Child, Preschool↗
PubMed1990

Penile agenesis: a fatal variation of an uncommon lesion.

Two male neonates (46XY karyotype) were born with a triad of penile agenesis associated with imperforate anus and complete absence of the median raphe. Both patients died of renal dysplasia and secondary pulmonary hypoplasia shortly after birth. This triad appears to be secondary to a lack of caudal mesoderm migration during month 1 of gestation, leading to severe developmental defects in the caudal axis. In all reported cases to date this triad of findings has been incompatible with extrauterine life.

Abnormalities, Multiple↗
PubMed1990

The effect of hypoprolactinemia alone and in combination with cyclosporine on allograft rejection.

Recent evidence suggests that prolactin has a role in regulating immune function. Hypophysectomy or administration of bromocriptine results in suppression of the immune response, which is reversed by the administration of prolactin. Hypoprolactinemia has been shown to augment the immunosuppressive effect of cyclosporine. We studied the effect of hypoprolactinemia induced by a new drug, CQP 201-403, on the survival of heterotopic cardiac allografts in the rat and the ability of peripheral blood lymphocytes to respond in vitro to plant mitogens. CQP treatment alone produced a small increase in graft survival but no change in lymphocyte in vitro proliferation (P less than 0.05). CQP treatment greatly enhanced the immunosuppressive effect of cyclosporine on graft rejection and in vitro lymphocyte function (P less than 0.02). We conclude that modulation of prolactin may be a useful adjunct to cyclosporine immunosuppression.

Animals↗
PubMed1989

Serum erythropoietin levels after renal transplantation.

We measured serum erythropoietin levels serially in 31 renal-transplant recipients treated with cyclosporine, using the recently developed recombinant human erythropoietin-based radioimmunoassay. The mean (+/- SEM) serum erythropoietin concentration in these patients before transplantation (14 +/- 2 U per liter) was similar to that in normal subjects who did not have anemia. A transient postoperative 9-fold increase (range, 0- to 74-fold) in the serum erythropoietin levels was followed by a smaller (3-fold) and sustained (28 +/- 3 days) second elevation. The initial increase occurred in the absence of graft function and was not accompanied by an erythropoietic response, whereas the second increase was associated with graft recovery and the complete resolution of the anemia. Serum erythropoietin levels returned to normal as the hematocrit rose above 0.32. Thereafter, the hematocrit continued to rise toward normal, while the serum erythropoietin levels remained normal. The patients in whom erythrocytosis or iron-deficiency anemia developed had persistently elevated serum erythropoietin levels. We conclude that in patients who have undergone renal transplantation, slight increases in endogenous erythropoietin levels induce erythropoiesis to the same extent as do large doses of exogenous erythropoietin in patients with uremia. Moreover, once initiated, erythropoiesis in renal-transplant recipients may be sustained by normal serum erythropoietin levels. These results suggest that the restoration of renal function improves the erythropoietic response to erythropoietin.

Adult↗
PubMed1989

Complications of bladder mucosal graft.

A bladder mucosal graft for urethral reconstruction was performed on 79 patients who had complicated conditions in which local penile or preputial skin was not available. The major and minor complication rates for this procedure were 15.2 and 43 per cent, respectively, the latter representing mucosal glanular protrusion obviated by a technical alteration. Given the difficulty of these cases these complication rates are deemed acceptable in such patients.

Humans↗
PubMed1989

Erythropoietin in renal transplant recipients: studies based on recombinant human erythropoietin radioimmunoassay.

In posttransplant patients, modest increases in endogenous EPO induce erythropoiesis similar to that observed in uremic patients who are given large doses of exogenous rHuEPO that generate vastly higher circulating EPO levels. Moreover, once it is initiated, erythropoiesis may be sustained by normal levels of EPO. These observations raise the possibility that the restoration of renal function may alter the EPO-erythropoiesis response pattern. It is also possible that the resolution of uremic anemia is dependent on factors in addition to the level of circulating EPO.

Biomarkers↗
PubMed1988

Declining incidence of wound infection in cadaveric renal transplant recipient.

Over a five-year period 100 cadaveric renal transplants were performed. In 91 of these recipients, a prophylactic parenteral antibiotic (cefoperazone) was administered and closed wound drainage was used. Of these 91 patients, 33 received azathioprine/prednisone immunosuppression, whereas cyclosporine/prednisone with or without azathioprine was used in the remaining 58. The incidence of wound infections was significantly reduced from 12 per cent (4/33) in the azathioprine group to 1.7 per cent (1/58) in the cyclosporine group (p less than 0.01). When conventional immunosuppression (azathioprine/prednisone) is employed in renal transplantation, triple antibiotic prophylaxis that includes an aminoglycoside is most effective in preventing wound infections. A single non-nephrotoxic antibiotic, cefoperazone, offers similar protection in the cyclosporine/prednisone-treated renal transplant recipient.

Cadaver↗