Biomedical subjects

D A Husmann

Publications and source records attributed to D A Husmann.

At least 73 records · Page 4Linked to original sources

PubMed1993

Hypertension following primary bladder closure for vesical exstrophy.

Since the initiation of staged reconstruction for bladder exstrophy, hypertension has been a known complication of the procedure. The etiology of the elevation in blood pressure was presumably secondary to ureteral dysfunction caused by edema at the ureterovesical junction and secondary renal obstruction. This report details the clinical course of three patients who developed significant hypertension following primary bladder closure with posterior iliac osteotomies and bony immobilization by skin traction. None of the patients had urinary obstruction and all had their hypertension alleviated by removal of the traction. The presumed etiology of the elevated blood pressure within these patients is similar to that experimentally produce by inappropriately applied traction resulting in tension on the sciatic nerve and reflex induced vasoconstriction. The need to maintain appropriately applied traction and the necessity of monitoring the postoperative blood pressure is stressed.

Antihypertensive Agents↗

PubMed1993

Ureteropelvic junction disruption following blunt abdominal trauma.

Disruptions of the ureteropelvic junction following blunt abdominal trauma are rare. Our recent management of 8 cases (7 patients) revealed that an immediate diagnosis of this entity was made in less than 50% of the patients. The majority of delayed diagnoses occurred when the patients experienced absence of hematuria associated with nonresponsive hypovolemic shock. The clinical instability of the patients required emergency celiotomy for stabilization and precluded our obtaining appropriate contrast enhanced radiographic studies. Retroperitoneal findings at operation failed to reveal evidence of a perinephric hematoma. The kidneys were palpably normal and, therefore, they were not directly examined. Despite these negative retroperitoneal findings the patients sustained disruption of the ureteropelvic junction. Therefore, we stress that a negative exploratory laparotomy without direct visualization of the kidney should not exclude radiographic evaluations for retroperitoneal injuries.

Abdominal Injuries↗

PubMed1993

Management of low velocity gunshot wounds to the anterior urethra: the role of primary repair versus urinary diversion alone.

The management of partial transection of the anterior urethra following penetrating penile injuries is controversial. Optional therapeutic techniques range from a primary sutured reapproximation to urinary diversion alone. We recently managed 17 low velocity gunshot wounds to the external genitalia in which the missile traversed the penile corpus cavernosum, and was associated with less than 40% transection of the corpus spongiosum and anterior urethra. Nine patients were managed with suprapubic diversion, skin débridement and corporeal closure along with placement of a urethral catheter. Eight patients were managed by suprapubic diversion, débridement, closure of the corporeal bodies and a primary sutured reapproximation of the anterior urethra. Urethral strictures developed in 7 patients (78%) managed by a suprapubic tube and urethral stenting during an average followup of 20 months (range 18 to 24). In contrast, 1 patient (12%) managed by a sutured urethral approximation had a urethral stricture during an average followup of 20 months (range 18 to 30, p < 0.01). Our data support a significantly better prognosis for partial transection of the anterior urethra secondary to low velocity gunshot wounds if managed by aggressive wound débridement, corporeal repair, placement of a suprapubic catheter and primary repair of the urethra.

Humans↗

PubMed1993

A comparison of the bioeffects of four different modes of stone therapy on renal function and morphology.

A variety of therapeutic options exists for removal of symptomatic renal calculi, including extracorporeal shock wave lithotripsy, percutaneous nephrostolithotomy and open pyelolithotomy or nephrolithotomy. Although lithotripsy offers the advantage of reduced patient morbidity, the relative alterations in renal function and morphology for each of the respective treatment modalities have not been completely assessed. We evaluated 17 pigs (40 to 50 lb.) for evidence of histologic and functional renal changes after a pyelotomy (N = 3) or nephrotomy (N = 4), piezoelectric lithotripsy (N = 5), or placement of a percutaneous nephrostomy tube with balloon dilation (N = 5). Pathologic evaluation one month after treatment revealed no renal scarring in the animals that underwent a pyelotomy and minimal parenchymal fibrosis in the nephrotomy and lithotripsy groups (0.014 +/- 0.001% and 0.015 +/- 0.002%, respectively). In contrast, the percutaneous nephrostomy group demonstrated 1.53 +/- 0.4% of the treated kidney to be involved by scarring (p < 0.001). Despite the statistically significant increase in renal scarring after percutaneous nephrostomy, neither creatinine and PAH clearances nor renal plasma flows changed significantly among the four treatment groups. Moreover, no change in renal function after treatment was observed when compared with baseline evaluations. All four therapeutic options for renal stone removal appear to result in small amounts of renal parenchymal damage but are not associated with significant alterations in renal function.

Animals↗

PubMed1993

Major renal lacerations with a devitalized fragment following blunt abdominal trauma: a comparison between nonoperative (expectant) versus surgical management.

Of 43 patients who sustained blunt trauma resulting in a major renal laceration with a devitalized fragment 27 had coexisting intraperitoneal and renal injuries for which emergency celiotomy and repair of the nonurological trauma were done. Management of the renal injuries consisted of simultaneous renal exploration with 23% urological morbidity in 13 cases or expectant management with 85% urological morbidity in 14 cases. In this latter patient population infected urinomas and perinephric abscesses seeded from coexisting enteric or pancreatic injuries were the most common complication (57%). The remaining 16 of the 43 patients sustained renal lacerations without associated intraperitoneal injuries and all were managed expectantly with 38% urological morbidity. These findings suggest that renal exploration and surgical repair significantly improve the prognosis only in patients with simultaneous intraperitoneal and renal injuries (p < 0.01).

Abdominal Injuries↗

PubMed1992

Postpubertal genitourinary function following posterior urethral disruptions in children.

A total of 24 boys sustaining a simultaneous pelvic fracture and posterior urethral disruption was observed from the time of injury through puberty. Average length of followup was 6 years. In contrast to the adult, in whom the urethra is invariably injured at the prostatomembranous junction, the posterior urethral disruptions in the prepubertal patient were at 3 distinct locations: 1) supraprostatic in 4 patients, 2) transprostatic in 4 and 3) prostatomembranous in 16. Prolonged followup through puberty in these children revealed that the frequency of complications was significantly higher for urethral injuries proximal to the prostatomembranous region compared to those at this latter site: impotence 75% versus 31%, intractable strictures following repairs 75% versus 12% and urinary incontinence 25% versus 0%. In summary, the prognosis of children who sustain a posterior urethral disruption should be based on the location of the injury and must remain guarded until the individual attains a postpubertal status.

Adolescent↗

PubMed1992

Urethral injuries in female subjects following pelvic fractures.

Pelvic fractures resulting from high speed motor vehicle and/or pedestrian-motor vehicle accidents commonly coexist with urethral injuries in the male patient. A review of 130 female patients with pelvic fractures managed at our institution revealed coexisting urethral injuries in 6 (4.6%). Partial urethral disruptions accounted for the majority of morbidity with early removal of the Foley catheter resulting in urinary extravasation, voiding difficulties and vulvar edema. In 3 patients the injury was misdiagnosed, 2 of whom had life-threatening sepsis with necrotizing fascitis as a consequence. Blood at the vaginal introitus was noted in more than 80% of our patients. However, only half of them had a careful vaginal inspection. If this pertinent portion of the physical examination had been performed more than two-thirds of our patients could have been correctly diagnosed. The need for meticulous vaginal examination when blood is located at the vaginal introitus, and the need for careful cystoscopic and/or radiographic evaluations in the female patient with voiding difficulties and/or vulvar edema in the acute post-traumatic phase are stressed.

Accidents, Traffic↗

PubMed1992

Exstrophy of the bladder: primary closure after iliac osteotomies without external or internal fixation.

A total of 6 consecutive infants with exstrophy of the bladder underwent iliac osteotomy in association with primary closure of the bladder without internal or external fixation of the bony pelvis. Hospitalization time was short and there were no resulting problems with healing, bony deformities or subsequent ambulation. Fixation of the bony pelvis after iliac osteotomy does not appear to be necessary in nonambulatory patients undergoing primary closure for bladder exstrophy.

Bladder Exstrophy↗

PubMed1992

Reversal of flutamide-induced cryptorchidism by prenatal time-specific androgens.

The recent discovery of time-specific antiandrogens (flutamide) to induce undescent of the testes has provided us the ability to study androgen therapy for cryptorchidism in the first specific antiandrogen animal model for testicular descent. Postpartal administration of pharmacological doses of testosterone, dihydrotestosterone, or human chorionic gonadotropin failed to reverse antiandrogen-induced cryptorchidism. Reduction in the frequency of testicular undescent occurred only when these agents were administered before parturition. Indeed, statistically significant reductions in the incidence of undescended testes occurred only when androgens were administered simultaneously with the antiandrogens on gestational days 16-17. However, the successful ability of prenatal dihydrotestosterone or testosterone to prevent cryptorchidism was associated with significant complications of prenatal androgen therapy. Specifically, 100% (46 of 46) of the animals that had inhibition of flutamide-induced cryptorchidism manifested findings of hypogonadotropic hypogonadism. The findings of descended diminutive testes and epididymis in these latter animals did, however, substantiate that testicular weight does not play a significant role in descent of this organ. In summary, these studies delineate a narrow window of time in which androgens act to effect testicular descent that is independent of testicular size.

Androgens↗

PubMed1991

Continence in bladder exstrophy: determinants of success.

We evaluated 19 female and 18 male patients with bladder exstrophy, who had completed staged reconstruction, had required no further surgery and underwent urodynamic studies. Of the male population 61% were continent based on a significantly higher urethral continence length (25.8 +/- 6.4 mm., mean plus or minus standard error) and a higher urethral closing pressure (69.4 +/- 5.8 cm. water) compared to the incontinent male population (11.4 +/- 3.1 mm. and 43.4 +/- 4.6 cm. water). No significant difference was noted in the bladder capacity of these 2 groups. Of the female population 57.9% were continent. They also demonstrated a higher urethral continence length (21.1 +/- 4.4 mm.) and a higher urethral closing pressure (62.7 +/- 10.2 cm. water) compared to the incontinent female subjects (8.4 +/- 2.5 mm. and 32.7 +/- 6.9 cm. water). Moreover, those who were continent had a significantly higher bladder capacity (201.2 +/- 39.5 ml.) compared to those who were incontinent (84.3 +/- 23.6 ml.). These findings support a multifactorial mechanism in achieving continence but they suggest that of all the factors urethral length may be the most important.

Bladder Exstrophy↗

PubMed1991

A comparison of renal damage induced by varying modes of shock wave generation.

To evaluate for the possible differences in the extent of pathologic injury occurring following treatment with various lithotripsy modalities, we subjected rabbits to treatment on either an electrohydraulic, electromechanical, or piezoelectric lithotripter. Functional evaluations by enzymuria failed to reveal any difference in the extent of damage between the lithotripters. Pathologic evaluation of the kidneys revealed that both electrohydraulic and electromechanical lithotripsy resulted in an increased instance of acute subcapsular hematoma and fibrosis when compared to piezoelectric treated kidneys (p less than 0.001). Despite the definitive differences noted in the acute animals, there was no significant variation in the area of permanent renal damage that occurred between the various lithotripters.

Acetylglucosaminidase↗

PubMed1991

Temporal effects of shock wave lithotripsy.

Previous studies have demonstrated that renal parenchymal injury following extracorporeal shock wave lithotripsy is dependent upon shock wave power as well as the total number of shock waves administered. In order to determine the deleterious effects of temporal versus cumulative doses of shock wave administration, adult female rabbits were divided into five groups receiving either: 1000 shock waves in one session; 2000 shock waves in one session; 2000 shock waves in two sessions, one week apart; unilateral nephrectomy without lithotripsy; or anesthesia only as control population. One month following lithotripsy, renal functional studies for gamma glutamyl transferase and N-acetyl-beta-glucosaminidase revealed persistent enzymuria in the animals treated with 2000 shocks in one session. Pathologic studies in these animals confirmed an increased area of periglomerular and intratubular fibrosis when compared to animals managed by either 1000 shocks or 2000 shocks in divided doses (p less than 0.01). These findings suggest the importance of avoiding single treatments with large doses of shock waves and favor the administration of multiple small-doses of shock waves to minimize renal damage during the treatment of patients with hard or large calculi.

Acetylglucosaminidase↗

PubMed1991

Resolution of vesicoureteral reflux in completely duplicated systems: fact or fiction?

A total of 60 patients (71 renal units) with grade 2/5 vesicoureteral reflux into the lower pole moiety of a completely duplicated system was managed by medical surveillance and is compared to an identically managed age, race and sex matched control population with a similar degree of reflux into a single collecting system. During a median 2-year observation period reflux ceased spontaneously in 10% of the patients with duplication compared to 35% of the control population (p less than 0.01). Comparisons between the 2 study groups failed to reveal a difference in the incidence of break-through urinary tract infections, advancing degrees of reflux and/or the development or progression of renal scarring (p greater than 0.5). Despite the fact that the resolution rate in duplex systems is significantly lower than that of a single system, it is apparent that cessation of grade 2/5 reflux into a duplicated ureter will occur and that a trial of medical management is an appropriate initial method of therapy.

Actuarial Analysis↗

PubMed1991

Cloacal anomalies and other urorectal septal defects in female patients: a spectrum of anatomical abnormalities.

The anatomy and management of 16 female patients with urorectal septal defects have been reviewed. The diagnosis was often confused by the anomalous appearance of the external genitalia, and the internal arrangements of the urinary tract, genital tract and lower intestinal tract were frequently bizarre and unpredictable. Because of the potential of these patients for secondary infection and sepsis, a prompt and thorough anatomical evaluation in such cases is essential. Initial treatment should be directed toward decompression of the involved organ systems and definitive reconstruction should be deferred until the child is older, at which time the emphasis should be upon a simultaneous multisystem repair performed, whenever possible, in 1 stage.

Abnormalities, Multiple↗

PubMed1991

Localization of the androgen receptor in the developing rat gubernaculum.

The distribution of androgen receptor expression within the developing rat gubernaculum was examined at different times during fetal and neonatal development using polyclonal antibodies directed at the amino-terminus (amino acids 1-21) and the carboxy-terminus (amino acids 898-917) of the androgen receptor. These studies reveal a high level expression of androgen receptor in the undifferentiated cells that comprise the mesenchymal core of the gubernaculum in early development. However, during the morphological alterations of the gubernaculum into a muscular structure, the level of androgen receptor detected in these cells declines, with minimal immunoreactivity present 2 weeks postpartum. Whether the loss of staining of the mesenchyme is related to decreases in androgen receptor expression, death of the mesenchymal cells, or differentiation of these cells into myoblasts remains to be determined.

Aging↗

PubMed1991

Androgen receptor expression in the developing rat prostate is not altered by castration, flutamide, or suppression of the adrenal axis.

Mesenchymal epithelial interactions are believed to be important to the growth and development of the neonatal prostate. Prior studies in the rat ventral prostate, using autoradiography and tritiated dihydrotestosterone, indicate that androgen receptors are present in the prostatic stroma on day 3 and are detected in the epithelium by the tenth postnatal day. These findings suggested that androgen stimulation of the prostatic mesenchyme is a crucial step in the growth and development of the prostate. We have examined this developmental program directly using polyclonal antibodies that recognize specific epitopes of the androgen receptor to examine the pattern of androgen receptor expression in intact and neonatally castrate animals. In keeping with previous studies, androgen receptors are present in the prostate stroma at birth and subsequently appear in the prostatic epithelium by the 10th postnatal day. Development of androgen receptor expression in the epithelium was not changed when the animals were castrated at birth, castrated and blocked by flutamide, or castrated and given hydrocortisone to suppress the production of adrenal androgens. These findings suggest that the appearance of androgen receptors in the prostatic epithelium is programmed by androgens before birth or that factors other than testicular or adrenal androgens control the development of epithelial androgen receptors.

Adrenal Glands↗

PubMed1991

Androgen receptor levels in the rat penis are controlled differently in distinctive cell types.

The rat phallus grows during sexual maturation as serum androgen concentrations rise to adult levels, and growth ceases when sexual maturity is attained despite the continued presence of adult serum androgen levels. This cessation of growth is correlated temporally with a diminution in the levels of androgen receptor, as detected by assays of ligand binding. To determine whether the change in androgen receptor content occurs in all cells in the tissue, immunohistochemical studies of the penile androgen receptor were performed in rats of different ages. In immature animals and animals castrated prepubertally, the androgen receptor is detected in virtually all cell types, including the corpus cavernosum penis, the small lateral cavernous bodies, the corpus cavernosum urethra, skin, urethra, and os penis. By contrast, in the mature rat penis minimal androgen receptor is evident within the corporal tissue and os, although immunoreactivity remains detectable in the penile skin and urethra. It is concluded that the cessation of androgen-mediated growth correlates with a decrease in androgen receptor levels in the body of the penis.

Aging↗

PubMed1991

Time-specific androgen blockade with flutamide inhibits testicular descent in the rat.

Inhibition of androgen action by flutamide, a nonsteroidal antiandrogen, blocked testicular descent in 40% of the testes exposed to this agent continuously from gestational day 13 through postpartal day 28. By contrast, only 11% of the testes failed to descend when blocked by 5 alpha-reductase inhibitors during the same period. Flutamide administration over narrower time intervals (gestational day 13-15, 16-17, or 18-19) revealed maximal interference with testicular descent after androgen inhibition during gestational days 16-17. No significant differences in testicular or epididymal weights were evident between descended and undescended testes; furthermore, no correlation was detected between the presence of epididymal abnormalities and testicular descent. These findings indicate that androgen inhibition during a brief period of embryonic development can block testicular descent. The mechanism through which this inhibition occurs remains to be elucidated.

5-alpha Reductase Inhibitors↗