H. Gil Rushton

Renal Scarring Following Reflux and Nonreflux Pyelonephritis in Children: Evaluation with 99mTechnetium-Dimercaptosuccinic Acid Scintigraphy

99mTechnetium dimercaptosuccinic acid (DMSA) scintigraphy is the imaging modality of choice for the detection of acute pyelonephritis and chronic renal scarring in children. Using the DMSA scan we prospectively evaluated renal scarring after reflux and nonreflux pyelonephritis in children. The study population consisted of 33 patients with acute pyelonephritis documented by a DMSA renal scan at infection. The children were evaluated for renal scarring with a followup DMSA scan 4 to 42 months (mean 10.7 months) after the acute infection. All new scarring on followup DMSA scans occurred at sites corresponding exactly to areas of acute inflammation on the initial DMSA scan. Therefore, only those kidneys with acute changes on the initial scan were subsequently analyzed. Of 38 kidneys new or progressive scarring developed in 16 (42%), including 6 of 15 (40%) with associated vesicoureteral reflux and 10 of 23 (43%) without demonstrable reflux. New renal scarring developed in 6 of the 7 kidneys (86%) associated with a neuropathic bladder or posterior urethral valves. In contrast, new scarring developed in only 10 of 31 kidneys (32%) associated with a normal bladder (p = 0.028). Excluding the kidneys associated with a neuropathic bladder or posterior urethral valves, new renal scarring developed in 3 of 12 (25%) with primary reflux, compared with 7 of 19 (37%) without vesicoureteral reflux. Except for the white blood count and the species of infecting bacteria, no other statistically significant differences could be found between those cases in which scars did or did not develop. We conclude that acquired renal scarring only occurs at sites corresponding to previous areas of acute pyelonephritis, the acute parenchymal inflammatory changes of acute pyelonephritis are reversible and do not lead to new renal scarring in the majority of cases, and once acute pyelonephritis has occurred ultimate renal scarring is independent of the presence or absence of vesicoureteral reflux.

Dimercaptosuccinic Acid Renal Scintigraphy For The Evaluation of Pyelonephritis and Scarring: A Review of Experimental and Clinical Studies

Renal cortical scintigraphy has been reported to be useful in children for confirmation of the diagnosis of acute pyelonephritis. Subsequent experimental studies have demonstrated that dimercaptosuccinic acid (DMSA) scintigraphy, when compared directly with histopathology, is highly reliable for the detection and localization of parenchymal inflammatory changes associated with acute pyelonephritis. Recent clinical studies of acute pyelonephritis using DMSA scintigraphy reveal that the majority (50 to 91%) of children with febrile urinary tract infections have abnormal DMSA renal scan findings and that the majority of these children do not have demonstrable vesicoureteral reflux. However, when vesicoureteral reflux is present, renal cortical abnormalities are demonstrated by DMSA scintigraphy in 79 to 86% of the kidneys. In children with febrile urinary tract infections routine clinical and laboratory parameters are not reliable in the differentiation of acute pyelonephritis, documented by DMSA renal scan findings, from urinary tract infections without parenchymal involvement. Furthermore, the presence of P-fimbriated Escherichia coli associated with febrile urinary tract infections does not reliably predict those kidneys that have acute parenchymal inflammation demonstrated by DMSA renal scans. DMSA is also the isotope agent of choice for the detection of renal scarring. Clinical studies report greater sensitivity of DMSA renal scintigraphy for the detection of renal scarring when compared with the excretory urogram, particularly in infants and young children. In a recent prospective study of post-pyelonephritic renal scarring in children we found that acquired renal scarring only occurs in sites corresponding exactly to previous areas of acute pyelonephritis demonstrated by DMSA scintigraphy at the time of infection. Furthermore, once acute pyelonephritis occurs, ultimate renal scarring is independent of the presence or absence of vesicoureteral reflux. These findings provide convincing evidence that renal parenchymal infection, rather than vesicoureteral reflux, is the prerequisite for acquired (postnatal) renal scarring. Vesicoureteral reflux as a risk factor for acquired renal scarring is directly related to its role as a risk factor for acute pyelonephritis. We conclude that DMSA scintigraphy is a valid tool for confirming the diagnosis of acute pyelonephritis in children and for identifying kidneys at risk for subsequent renal scarring.

EVALUATION OF 99MTECHNETIUM-DIMERCAPTO-SUCCINIC ACID RENAL SCANS IN EXPERIMENTAL ACUTE PYELONEPHRITIS IN PIGLETS

We evaluated the sensitivity and specificity of 99mtechnetium-dimercapto-succinic acid renal scans in the detection and localization of experimental acute pyelonephritis in piglets. To create pyelonephritis vesicoureteral reflux of infected urine was surgically induced in 22 piglets. Nine animals were evaluated with a dimercapto-succinic acid renal scan at 1 week and 13 at 2 weeks. Autopsy and histopathological examination of the kidneys were performed subsequently. The location and extent of the inflammatory response found on histopathological examination were compared to dimercapto-succinic acid renal scan findings in a blinded fashion. Of the 22 kidneys subjected to vesicoureteral reflux 15 had positive histopathological findings of acute pyelonephritis, including 13 detected by the dimercapto-succinic acid renal scan findings. The 2 kidneys in which inflammation was not detected had only minimal grade I lesions and were grossly normal. There were no false positive scans in any of these kidneys. The sensitivity of the scan for detection of acute pyelonephritis in the kidneys subjected to reflux was 87 per cent and the specificity was 100 per cent. Furthermore, in these same kidneys the dimercapto-succinic acid renal scan findings correctly predicted the presence or absence of individual pyelonephritic lesions in 62 of 66 poles for an over-all agreement rate of 94 per cent. Thus, dimercapto-succinic acid renal cortical imaging is a highly sensitive and reliable imaging modality to detect and localize experimental acute pyelonephritis in piglets.

Testicular sparing surgery for prepubertal teratoma of the testis : a clinical and pathological study

We report on 5 patients 14 months to 6 1/2 years old with prepubertal teratoma of the testis treated by testicular sparing tumor enucleation. All 5 patients had no evidence of recurrence at a mean followup of 96 months. Recognizing that this is not accepted therapy for testis tumors, 17 orchiectomy specimens containing teratoma from children were histologically analyzed in cooperation with the Armed Forces Institute of Pathology Tumor Registry. All patients were prepubertal at orchiectomy (3 months to 8 years old) and all are well with a mean followup of 174 months. Histological examination revealed no foci of teratoma separate from the main tumor in any specimens. Immunohistochemical studies with placental alkaline phosphatase, a marker for malignant germ cells, were done to detect carcinoma in situ in the seminiferous tubules of these testes. This test did not reveal any intratubular malignant germ cells (carcinoma in situ). Based on our clinical experience with testicular sparing tumor enucleation, the histological findings on Armed Forces Institute of Pathology review demonstrating no associated carcinoma in situ and the universally benign behavior of prepubertal testicular teratomas, we recommend a testicular sparing operation rather than orchiectomy for testicular teratoma in prepubertal patients.

Nocturnal enuresis: epidemiology, evaluation, and currently available treatment options.

Treatment of childhood enuresis must begin with a careful history, physical examination, urinalysis, and urine culture to determine if one is dealing with uncomplicated or complicated enuresis. The majority of patients will have uncomplicated enuresis; there are several treatment options available to the physician that can be tailored to the individual patient. Parental support, empathy, and patience are key elements in any successful plan of management of the child with enuresis. Likewise, reassurance, periodic feedback, and encouragement of the parents and child by the physician are necessary for optimal results.

DIAGNOSIS AND MANAGEMENT OF TERATOMAS AND EPIDERMOID CYSTS

One can strongly suspect a benign lesion in a prepubertal child on the basis of preoperative sonographic, biochemical, and clinical evaluation; however, when considering a testis-sparing enucleation, the definitive diagnosis must be established by pathologic frozen section of the tumor. The high incidence of benign testicular lesions in the prepubertal patient, the absence of associated carcinoma in situ in prepubertal germ cell tumors, and the universally benign behavior of the specific tumors described in this article are supportive evidence for testis-sparing surgery versus orchiectomy, for these benign lesions.

Pyelonephritis in Male Infants: How Important is the Foreskin?

We investigated the association of the uncircumcised foreskin and pyelonephritis in male infants less than 6 months old. During a 21-month prospective study 94 children (age range 2 weeks to 18.9 years) were hospitalized for febrile urinary tract infection. The male-to-female ratio for 35 patients less than 6 months old was 2.2:1. Of 59 patients older than 6 months the male-to-female ratio was reversed at 0.25:1 (p less than 0.001). In 13 of 24 infants (54%) less than 6 months old and in 8 of 12 boys (67%) older than 6 months a dimercaptosuccinic acid renal scan documented acute parenchymal damage (p = 0.72). Vesicoureteral reflux or other genitourinary abnormalities were found in only 3 of 24 patients (12.5%) less than 6 months old compared with 6 of 12 boys (50%) older than 6 months (p = 0.036). Of 24 infants less than 6 months old 22 (92%) were uncircumcised compared with 6 of 12 boys (50%) older than 6 months (p = 0.009). We then retrospectively compared the circumcision status of the infants who had febrile urinary tract infection with a control group of 63 infants matched for age, race and socioeconomic status hospitalized with febrile upper respiratory infection during a similar period. The frequency of uncircumcised infants in the control group with febrile upper respiratory infection was only 44% (28 of 63) compared with 91% of infants with febrile urinary tract infection (p less than 0.001). Overall the findings of the male predominance among patients less than 6 months old with febrile urinary tract infection, the disproportionately high frequency of infants with febrile urinary tract infection who were not circumcised, and the disproportionately low occurrence of vesicoureteral reflux and other genitourinary abnormalities in infants with febrile urinary tract infection strongly support an association between circumcision status and the risk for febrile urinary tract infection and pyelonephritis in male infants.

Renal scarring and vesicoureteral reflux in children with myelodysplasia

The records of 180 myelodysplasia patients followed from 3 to 18 years were reviewed. Studies included cystography to evaluate vesicoureteral reflux and dimercapto-succinic acid renal scintigraphy to identify acute inflammation and renal scarring. Scarring was noted in 28 of 180 patients (15.5%), of whom 68% were girls. Of the patients with renal scarring 75% had associated reflux and 40% over-all were identified as having reflux. Management of patients with vesicoureteral reflux included clean intermittent catheterization, antibiotic prophylaxis and anticholinergics when indicated. Only 17 of 72 patients (24%) had ureteral reimplantation. Surgical indications included persistent high grade reflux and/or progressive upper tract damage. Reflux resolved in 62% of those on medical management. Resolution was not dependent on grade of reflux (as compared to primary reflux). Twenty-one patients are stable and being followed with persistent reflux. In 7 patients new renal scars developed during aggressive medical management, 5 of whom underwent subsequent surgical correction.

Intraoperative Spermatic Venography During Varicocele Surgery in Adolescents

Intraoperative internal spermatic venography performed immediately following varicocele ligation in the adolescent has been touted as reducing varicocele persistence rates. Previously published data corroborate this statement with low persistence rates. Other series in which venography was not performed report a failure rate of 9 to 30%. During a 5-year period a total of 64 varicocele ligations was performed in 62 male adolescents at our institution. Followup postoperatively revealed an overall varicocele persistence rate of 9%. All patients had intraoperative internal spermatic venography on the affected side. Of 64 venograms 16% had shown collateral drainage that, if not ligated, may have resulted in varicocele persistence. These cases accounted for only 1 of the persistent varicoceles. Additionally, venograms had demonstrated filling of the ipsilateral external iliac vein in 8% of the cases. Despite the fact that no attempt was made to ligate these collaterals, none of these patients had a persistent varicocele. After varicocele ligation 30 of 62 patients were followed long enough to evaluate for testicular catch up growth. Of these 30 patients 24 demonstrated an average relative increase in left testicular volume of 17%. These data support routine intraoperative internal spermatic venography while performing varicocele ligation in the adolescent.

A case of primary malignant lymphoma of the bladder in childhood.

Primary malignant lymphoma of the bladder is a rare entity. Review of the reported cases of bladder lymphoma in the literature reveals that bladder lymphoma is typically found in elderly patients. We report a well documented case of a non-Hodgkins primary bladder lymphoma in childhood. The unusual clinical presentation, immunochemical analysis, treatment and 5-year followup are discussed.