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Dive into the research topics where George F. Steinhardt is active.

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Featured researches published by George F. Steinhardt.


The Journal of Urology | 1997

New renal scars in children with urinary tract infections, vesicoureteral reflux and voiding dysfunction : A prospective evaluation

Shahida R. Naseer; George F. Steinhardt

PURPOSE Established renal scarring represents areas of the kidney that imaging reveals to be damaged at presentation for medical management of urinary tract infection. New renal scarring represents new renal damage in parts of the kidney that imaging reveals to be normal at presentation. We attempted to characterize patients in whom new renal scars developed while they were under our care. MATERIALS AND METHODS In 1988 a data base was started to identify patients with new renal scarring. All patients presenting with urinary tract infections were enrolled. Our data base has 250 possible fields per event with multiple events per patient. More than 2,100 patients have been enrolled to date. All patients with pyelonephritis, defined as a febrile urinary tract infection with flank pain and tenderness, and all with reflux underwent dimercapto-succinic acid (DMSA) scan at least 4 months after presenting with infection to assess established renal scars. New renal scars were identified when new renal defects were demonstrated on a second DMSA scan. RESULTS In our data base there are 1,426 patients with urinary tract infections, 685 (46%) with pyelonephritis and 1,062 (74.5%) with vesicoureteral reflux, including 558 found to have bilateral vesicoureteral reflux and 504 diagnosed with unilateral reflux. A history of daytime urinary incontinence was noted in 538 patients (37.7%), 192 (13.5%) had established scars at initial presentation and in 31 (2.1%) new renal scars developed while they were under our care, including 30 with established scars as well. Of the 25 patients in whom new renal scars developed while on medical therapy 11 underwent surgery. In 6 patients with dysfunctional voiding who were receiving medical treatment renal scars developed postoperatively. Surgery was performed in 17 of the 31 patients and 24 (77%) with new renal scars had a history of dysfunctional voiding. CONCLUSIONS Previous characterizations of patients with new renal scars have relied on excretory urography for assessing renal architecture and ignored voiding patterns of the children affected. Using the DMSA scan we identified 31 children with reflux, urinary tract infection and dysfunctional voiding in whom new renal scars developed while they were under our care.


The Journal of Urology | 2001

Cessation of prophylactic antibiotics for managing persistent vesicoureteral reflux.

R. Houston Thompson; John J. Chen; Jeff Pugach; Shahida Naseer; George F. Steinhardt

PURPOSE We reviewed our experience with patients with vesicoureteral reflux treated off prophylactic antibiotics. MATERIALS AND METHODS We retrospectively reviewed the records of patients with vesicoureteral reflux treated off prophylactic antibiotics, noting the intervals on and off antibiotics, urinary tract infection, signs and symptoms associated with urinary tract infection, and renal ultrasound and dimercapto-succinic acid scan findings. RESULTS We identified 196 patients with vesicoureteral reflux treated off prophylactic antibiotics, including 122 who were infection-free while on and 124 who had no urinary tract infection while off prophylactic antibiotics. The infection rate on and off prophylactics was 0.29 and 0.24 urinary tract infections per patient per year, respectively. New scars were identified in 5 patients while on prophylactics and in 7 after antibiotics were discontinued. Comparing different subgroups off prophylactic antibiotics showed that children who presented with scarring had statistically fewer new scars than those with normal initial dimercapto-succinic acid imaging (p <0.043). Girls had significantly more urinary tract infections than boys while off prophylactics (p <0.01) despite the older age at antibiotic cessation. However, after infection occurred while off prophylactic antibiotics, new renal scars developed at about the same rate in boys and girls. Because most patients did not have a urinary tract infection while off prophylactic antibiotics, new renal scars developed in only 2.2% of all boys and 4% of all girls. CONCLUSIONS Our findings imply that discontinuing antibiotics is reasonable and safe in patients in whom vesicoureteral reflux fails to resolve.


The Journal of Urology | 1993

Testicular torsion: pitfalls of color Doppler sonography.

George F. Steinhardt; Saul Boyarsky; Richard Mackey

Only 25% of boys with acute scrotal swelling have testicular torsion. A noninvasive test that reliably distinguishes torsed testes from all other acute scrotal conditions would benefit patients presenting with pain and swelling of the scrotum. Recent reports suggest that color Doppler ultrasound may be the long-awaited test that clearly differentiates testes with compromised blood flow from all other conditions. However, we report on 2 patients with positive blood flow on color Doppler ultrasonography who subsequently were found at surgery to have testicular torsion. Inability to distinguish normal testes and normal epididymis on physical examination is still the best indicator to proceed with surgical exploration in pediatric patients with acute scrotal swelling.


Advances in Experimental Medicine and Biology | 2004

Endocrine disruption and hypospadias.

George F. Steinhardt

The complexity of human biology makes it impossible to know for certain if endocrine disruption accounts for human penile deformities. Toxicologists point out that an overall assessment of risk must include other factors in addition to exposure including absorption, metabolism, excretion, bioaccumulation and other chemical interactions (Harrison et al., 1997). Many skeptics observe lack of analytic ability to document contaminant levels during critical windows of exposure (Safe, 2000). Further, the environmental estrogens studied (DDT, PCB and bis-phenol A) are quite weak compared to the well studied potent estrogen DES which did not cause penile deformities (Joffe, 2001). While environmental estrogens may be unlikely in contributing to penile deformities, the antiandrogens (phthalates, vinclozolin and DDE) are more plausible is this regard, as maleness is critically dependent upon androgen action. Observers note that, in general, the environmental concentrations of persistent organochlorine compounds have been decreasing over the past two decades. Some feel that our current levels of exposure are too low and the potency of the anti-androgens too weak to account for any significant developmental genital effect (Williams et al., 2001). Caution and restraint are always reasonable in matters of data intrepretation. Past researchers were reassured that pthtalate esters were quite safe when they first were assessed for possible harmful effects on male fertility. Unfortunately it took different models, analyzing transgenerational effects, before it became crystal clear that these compounds can dramatically affect male genital development following experimental maternal exposure at dosages and concentrations currently present in most women. We can not now be so reassured that our male development is unaffected by any of the over 65,000 manmade organochlorine compounds on the planet. Multiple observations from diverse disciplines provide credible evidence that proliferation of xenobiotic chemicals can cause potentially disastrous unintended consequences for the male gender, and upon reflection, our species.


The Journal of Urology | 1998

Sexual Mutilations: A Human Tragedy

George F. Steinhardt

Come with us to read a new book that is coming recently. Yeah, this is a new coming book that many people really want to read will you be one of them? Of course, you should be. It will not make you feel so hard to enjoy your life. Even some people think that reading is a hard to do, you must be sure that you can do it. Hard will be felt when you have no ideas about what kind of book to read. Or sometimes, your reading material is not interesting enough.


The Journal of Urology | 1997

BOTULINUM TOXIN: NOVEL TREATMENT FOR DRAMATIC URETHRAL DILATATION ASSOCIATED WITH DYSFUNCTIONAL VOIDING

George F. Steinhardt; Shahida Naseer; Oscar A. Cruz

A 7-year-old girl with previously diagnosed fetal alcohol syndrome presented with a 3-year history of lower urinary tract infections and daytime wetting. There was no history of febrile urinary tract infections, constipation or soiling. Renal ultrasound showed normal kidneys with mild bladder wall thickening. Voiding cystourethrography revealed no reflux but dramatic circumferential urethral dilatation and decompensation (part A of figure). Urodynamics demonstrated uninhibited contractions with detrusor-sphincter dyssynergia, which is typical of the pediatric uninhibited bladder. Therapy with behavioral modification, prophylactic antibiotics and anticholinergics was unsuccessful in controlling wetting andor urinary tract infections. Therefore, cystoscopy and periurethral injection of botulinum-A toxin were performed. Endoscopy revealed the urethra to be dilated circumferentially. The bladder neck was normal and there was tight coaptation of the external sphincter. This area was injected


Journal of Pediatric Surgery | 1992

The risk of abdominal operations in children with ventriculoperitoneal shunts

Thomas Pittman; Dianne Williams; Thomas R. Weber; George F. Steinhardt; Tom Tracy

Ventriculoperitoneal (VP) shunts are the operations of choice for patients with hydrocephalus in most pediatric hospitals. Children with VP shunts frequently undergo abdominal operations unrelated to their shunts, which might lead to shunt infections or to malfunctions related to adhesions. Although prophylactic antibiotics are usually used in this setting, there are few data to support their use, or to assess other risks to the shunt from the abdominal procedures. Consequently, we reviewed the records of 37 children with VP shunts who underwent a total of 44 abdominal operations. In 8 cases, the genitourinary (GU) tract was opened (ureteral reimplantation, bladder augmentation, nephrectomy), whereas in 18 patients the gastrointestinal (GI) tract was opened (appendectomy, gastrostomy, small/large bowel resection). In 18 operations neither GI nor GU tract was opened (lysis of adhesions, herniorrhaphy, orchiopexy). Antibiotic coverage was highly variable: 9 received no antibiotics, 9 received antibiotics only postoperatively, 4 were given antibiotics only preoperatively, and in 22 cases antibiotics were given both preoperatively and postoperatively. One shunt that was involved in a periappendiceal abscess was exteriorized and later successfully replaced. In the remaining cases, no episodes of shunt infection or malfunction occurred in 1 to 10 years of follow-up. Likewise, no abdominal cerebrospinal fluid pseudocysts formed as a result of abdominal adhesions. These data demonstrate that children with VP shunts can safely undergo abdominal operations, even when the GI or GU systems are opened, with minimal risk of shunt infection or malfunction. Rigid protocols of prophylactic antibiotics cannot be supported by this series.


The Journal of Urology | 1990

Long-Term Survival in an Infant with Urethral Atresia

George F. Steinhardt; William Hogan; Ellen G. Wood; Thomas R. Weber; Robert E. Lynch

Complete urethral atresia is an anomaly that previously was incompatible with life. We report on a surviving infant with this anomaly. As a fetus urinary decompression was accomplished with a vesicoamniotic shunt. Peritoneal dialysis was initiated shortly after birth and at 9 months supramembranous scrotal inlay urethroplasty was performed to provide for egress of urine from the bladder. A maternal renal allograft was performed when he was 12 months old. When the patient was 3 1/2 years old he had normal renal function and emptied the bladder to completion through the reconstructed urethra. Although mildly delayed, he continues to progress with all developmental milestones.


Pediatric Neurosurgery | 1995

Latex Allergy in Children with Spina bifida

Thomas Pittman; Jean Kiburz; Keith R. Gabriel; George F. Steinhardt; Dianne Williams; Jay E. Slater

We studied the prevalence of latex-specific IgE among the children in our myelomeningocele clinic and several groups of controls using skin tests, a commercially available ELISA and an in-house RAST. Thirty-nine of 83 (47%) children with myelomeningocele had antibodies directed against latex as did 6 of 40 (15.7%) chronically ill controls, 4 of 105 (3.8%) medical controls and 2 of 75 (2.7%) well controls. Within each study group the likelihood of a positive skin test increased with the number of operations the subject had undergone. Children with myelomeningocele were much more likely to have antibodies to latex than were chronically ill controls with similar surgical histories. A retrospective chart review of 18 years and a total of 646 operations disclosed only one episode of intraoperative anaphylaxis which appeared to be related to latex within our study group.


The Journal of Urology | 1988

Glomerulosclerosis in Obstructive Uropathy

George F. Steinhardt; G. Ramon; L. Salinas-Madrigal

Obstructive uropathy is said to result in populations of remnant nephrons subject to hyperfiltration. We studied all obstructed renal tissue removed at our pediatric institution during a 10-year period for focal segmental glomerulosclerosis, which is the histological hallmark of hyperfiltration. Over-all, the histological specimens from 20 patients with ureteropelvic junction obstruction, 14 who underwent heminephrectomy for duplication anomalies and 5 with posterior urethral valves who underwent native nephrectomy were studied. Focal segmental glomerulosclerosis was one of the most common histological findings in these obstructed kidneys but it almost always was found in association with intense interstitial and periglomerular inflammation. We conclude that although focal segmental glomerulosclerosis is common in obstructive uropathological conditions it results from the inflammatory response within the renal parenchyma and not from the hyperfiltration of remnant nephron populations.

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John J. Chen

University of Hawaii at Manoa

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George P. Vogler

Pennsylvania State University

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Helen Liapis

Washington University in St. Louis

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Hyeong Jun Ahn

University of Hawaii at Manoa

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Theodore Barber

University of Texas Southwestern Medical Center

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