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J W Brock

Publications and source records attributed to J W Brock.

At least 19 recordsLinked to original sources
PubMed2006

Continent catheterizable channels and the timing of their complications.

PURPOSE: We reviewed our experience with continent catheterizable channels with interest in the timing of conduit related complications. MATERIALS AND METHODS: A retrospective review was performed of the outcome of continent catheterizable channels in all patients between 1998 and 2003 who had undergone construction of an antegrade continence enema and/or a Mitrofanoff procedure using appendix, small bowel or continent cutaneous vesicostomy. We performed a total of 117 such stomas in 37 male and 41 female patients 2.5 to 20 years old (mean age 8.9). For the antegrade continence enema we used appendix in 92% of cases, an ileal Yang-Monti tube in 6% and a cecal tube in 2%. For the continent catheterizable channel we used appendix in 43% of cases, a Yang-Monti tube in 38% and continent cutaneous vesicostomy in 19%. RESULTS: Continence was achieved in 98% of patients. Followup was 6 to 71 months (mean 28.4). There were 27 channel related complications (23%). Stomal stenosis occurred in 7 antegrade continence enema procedures (14%) within 1 to 10 months (mean 6.2) and in 9 continent bladder channels (13%), including 5 continent cutaneous vesicostomies, within 1 to 24 months (mean 9.4) after surgery. False passages occurred in 5 antegrade continence enema procedures (10%) within 1 to 13 months (mean 3.6) and in 4 continent catheterizable channels (6%) within 1 to 13 months (mean 6.5) after surgery. Of patients with stomal stenosis 50% were treated with surgical revision, while the remainder was successfully treated with dilation. Most false passages were managed by catheter drainage alone. Reasons for revision were contained perforation, colovesical fistula and inability to catheterize. Patient noncompliance appeared to have a role in stomal stenosis. CONCLUSIONS: Continent catheterizable stomas help patients achieve bowel and bladder continence. Stomal incontinence after reconstruction is rare. In our experience most stoma related complications occurred in the first year after reconstruction. Experience with more patients and longer followup will help determine whether such problems continue to accumulate with time or whether continent stomas function well with time, particularly after the initial period of healing.

Adolescent↗
PubMed2005

Management of the failed pyeloplasty: a contemporary review.

PURPOSE: We reviewed our experience with open dismembered pyeloplasty, with specific focus on the presentation and management of failed pyeloplasty in the pediatric population. MATERIALS AND METHODS: We performed a retrospective review of patients who had undergone open dismembered pyeloplasty between 1998 and 2003. All patients with less than 6 months of followup were excluded from analysis. The patients were followed postoperatively with serial ultrasounds, with renograms reserved for those patients with prolonged, persistent or worsening hydronephrosis, or recurrent symptoms during followup. RESULTS: A total of 105 pyeloplasties were performed in 103 patients (71 males and 32 females) 1 to 204 months old (mean 60), with an overall success rate of 93.3%. Followup ranged from 6 to 69 months (mean 23). The 7 patients with treatment failure were males 1 to 204 months old (mean 125), who presented most commonly with pain within 3 to 38 months (mean 13.1) after initial surgery. Subsequent ultrasound revealed worsening hydronephrosis, and renography in these patients showed a pattern consistent with obstruction. Five patients underwent initial balloon dilation, in which 1 was successful. In addition, 1 of these patients underwent an unsuccessful antegrade laser endopyelotomy. Six patients (86%) underwent open surgery, consisting of ureterocalicostomy in 3 and reoperative dismembered pyeloplasty in 3. Dense scarring was seen in all patients, 2 patients had a redundant pelvis causing kinking and 2 patients had unrecognized crossing vessels. Overall salvage rate was 100% with continued followup of 3 to 50 months (mean 18). CONCLUSIONS: Dismembered pyeloplasty was successful in the vast majority of patients. In our series failures occurred as late as 3 years postoperatively, although most presented within 12 months of followup. Excluding routine postoperative nuclear renography did not seem to affect our ability to identify these cases. Although anatomical features such as renal pelvic size may have a role, failure is most likely secondary to technical issues, including missed crossing vessels and dependency of the anastomosis. In this series failed pyeloplasties did not respond well to balloon dilation, likely due to scar formation. Our current practice is to manage failures by open surgery, although endoscopic management by an incision may be an option.

Adolescent↗
PubMed2001

Association between maternal serum concentration of the DDT metabolite DDE and preterm and small-for-gestational-age babies at birth.

BACKGROUND: DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) is highly effective against most malaria-transmitting mosquitoes and is being widely used in malaria-endemic areas. The metabolite, DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), has been linked to preterm birth in small studies, but these findings are inconclusive. Our aim was to investigate the association between DDE exposure and preterm birth. METHODS: Our study was based on the US Collaborative Perinatal Project (CPP). From this study we selected a subset of more than 44000 eligible children born between 1959 and 1966 and measured the DDE concentration in their mothers' serum samples stored during pregnancy. Complete data were available for 2380 children, of whom 361 were born preterm and 221 were small-for-gestational age. FINDINGS: The median maternal DDE concentration was 25 mg/L (range 3-178)-several fold higher than current US concentrations. The adjusted odds ratios (OR) of preterm birth increased steadily with increasing concentrations of serum DDE (ORs=1, 1.5, 1.6, 2.5, 3.1; trend p<0.0001). Adjusted odds of small-for-gestational-age also increased, but less consistently (ORs=1, 1.9, 1.7, 1.6, 2.6; trend p=0.04). After excluding preterm births, the association of DDE with small-for-gestational-age remained. INTERPRETATION: The findings strongly suggest that DDT use increases preterm births, which is a major contributor to infant mortality. If this association is causal, it should be included in any assessment of the costs and benefits of vector control with DDT.

Adolescent↗
PubMed2001

Early evolution of bladder emptying after myelomeningocele closure.

OBJECTIVES: To analyze bladder emptying in newborns with spina bifida after closure of the myelomeningocele defect. Manipulation of the spinal cord and nerve roots results in temporary changes in bladder function in many settings. METHODS: We reviewed 62 consecutive newborn patients who underwent closure of a myelomeningocele defect at our institution from January 1990 to December 1997. We examined the catheterized urine volumes obtained before and after closure, radiographic and urodynamic studies, and the subsequent need for intermittent catheterization. Poor bladder emptying was defined as most catheterized urine volumes greater than 10 mL (20% of expected bladder capacity). Adequate follow-up was available for 54 patients for a period of 4 to 96 months (mean 42). One patient with posterior urethral valves was excluded from the study, leaving 53 for evaluation. RESULTS: Of the 53 patients, 4 with high outflow resistance and dyssynergy never emptied the bladder adequately before or after closure. Of the remaining 49 patients, 6 (12%) emptied well immediately after the myelomeningocele repair. In the other 43 (88%), the bladder did not empty as well after closure. The mean volume obtained with catheterization after closure was 20 mL, significantly higher (P <0.001) than the mean volume obtained before repair (6.5 mL) or after resumption of better spontaneous emptying (4 mL). Intermittent catheterization done for poor emptying was required for an average duration of 11 days (range 2 to 42). Of the 43 patients with poor emptying immediately after closure, 32 (74%) required catheterization for 2 weeks or less; the remaining 11 (26%) required catheterization for 2 to 6 weeks. Despite the relatively early resumption of good emptying, numerous patients (19 of 49) required additional intervention (clean intermittent catheterization or vesicostomy) before attempts to toilet train. CONCLUSIONS: A clinical pattern similar to spinal shock does occur in most newborns after closure of a myelomeningocele defect. Resumption of near-complete emptying usually occurs less than 2 weeks after repair but may require up to 6 weeks.

Female↗
PubMed2001

Is postoperative cystography necessary after ureteral reimplantation?

OBJECTIVES: To evaluate the patients in our practice to determine whether postoperative cystography was useful in monitoring the outcome after ureteroneocystostomy. Surgical repair of vesicoureteral reflux is the treatment of choice after medical therapy failure. Radiographic evaluation by ultrasonography or voiding cystourethrography (VCUG) is commonly used postoperatively to evaluate for urinary tract obstruction or persistent reflux. However, imaging modalities are not without cost, both in monetary terms and in terms of radiation exposure and trauma to the child. METHODS: We reviewed the records of all patients who underwent ureteroneocystostomy without ureteral tapering at our institution between January 1, 1996 and December 31, 1999 for primary vesicoureteral reflux. These records were evaluated with respect to the type of surgical procedure, preoperative and postoperative clinical course, and radiographic studies performed. RESULTS: We performed reimplantation on 267 renal units in 153 patients. The surgical technique was the Cohen cross-trigonal in 120 renal units (45%), Glenn-Anderson ureteral advancement in 92 (35%), and modified Leadbetter-Politano ureteral advancement in 55 (20%). All patients underwent imaging with ultrasonography within 6 weeks of surgery. The follow-up ranged from 4 to 42 months (average 14.2). Between 3 and 8 months postoperatively, 61 patients underwent imaging with VCUG. We identified persistent reflux in six renal units. Four of six had marked improvement in their reflux. All the patients with persistent reflux were asymptomatic, including 2 patients who were no longer receiving antibiotics. Four patients developed febrile urinary tract infections postoperatively. Three of the four underwent imaging with VCUG after treatment; all three had no evidence of reflux. CONCLUSIONS: In our population, the addition of VCUG to the postoperative evaluation did not allow us to identify those patients at risk of febrile urinary tract infections. Patients in whom persistent reflux was identified were all asymptomatic. We continue to monitor patients with ultrasonography, but believe that VCUG often provides little benefit to these children.

Adolescent↗
PubMed2001

Congenital anomalies of the kidney and urinary tract--role of the loss of function mutation in the pluripotent angiotensin type 2 receptor gene.

PURPOSE: Recent studies of the human genome and genetic engineering experiments in mice revealed that congenital anomalies of the kidney and urinary tract commonly seen in newborns in various anatomical forms are polygenic disease, that is a disease caused by simultaneous defects in multiple genes. We discuss some possible genetic explanations of the classic theories of the formation of congenital kidney and urinary tract anomalies. MATERIALS AND METHODS: We reviewed classic and current theories regarding urinary tract development. Included in our review are recent results from our laboratory evaluating the genetic role of normal and abnormal urinary tract development. RESULTS: We observed a genetic abnormality that may explain many classic anatomical theories of congenital kidney and urinary tract anomalies. One of the genes involved in urinary tract ontogenesis is the angiotensin type 2 receptor gene, which is the "other" angiotensin receptor. While the type 1 receptor mediates essentially all known actions of angiotensin, including its hypertensive effect, relatively little is known about the angiotensin type 2 receptor. Careful dissection studies in mutant mouse embryos selectively lacking the angiotensin type 2 receptor gene revealed that this gene is pleiotropic, that is its defect causes not only ectopic ureteral budding from the wolffian duct, but also disturbance in other subsequent ontogenic events that are critical for the normal growth of the kidney and urinary tract. CONCLUSIONS: Many congenital anomalies of the kidney and urinary tract appear to share a common genetic cause. While these anomalies are caused by various genetic hits, abnormalities in the angiotensin type 2 receptor gene are often involved in this anomalous development. This review article offers a better understanding of the genetics involved in urinary tract development and ties some of the newly emerging genetic theories with classic anatomical theories.

Angiotensin II↗
PubMed2001

The use of radiography, urodynamic studies and cystoscopy in the evaluation of voiding dysfunction.

PURPOSE: Children with dysfunctional voiding disorder often undergo radiological, cystoscopic or urodynamic evaluation to identify an anatomical or organic cause. We determined the role of these studies in the evaluation, management and ultimate outcome of a large patient population with voiding dysfunction at a single institution. MATERIALS AND METHODS: We retrospectively evaluated the records of 1, 153 children with dysfunctional voiding disorder treated from 1990 to 1999. A thorough history and physical examination with specific emphasis on voiding patterns were done and urinalysis was performed in all cases. Ultrasound of the urinary system and excretory urography were done in 1,050 (91%) and 24 (2%) patients, respectively, while voiding cystourethrography was performed in 672 (58%), including 564 with a history of nonfebrile urinary tract infection. Cystoscopy and a formal urodynamic study were performed in 61 (5%) and 40 (3.5%) cases, respectively. RESULTS: Mean patient age at referral was 6 years (range 3 to 14). Of the children 74% were girls and 26% were boys. Physical examination of the abdomen, back, genitalia and neurological system was unremarkable in all cases. Ultrasound of the upper urinary system was normal in 1,018 patients (97%) and showed insignificant pyelectasis in 32 (3%). All 24 excretory urography studies were normal and voiding cystourethrography was normal in 470 of 672 cases (70%). Unilateral and bilateral low grade, and unilateral high grade reflux was present in 108, 19 and 3 patients, respectively. Urodynamic studies were performed in 40 children who did not respond to standard treatment. We noted detrusor instability in 16 patients, detrusor-sphincter dyssynergia in 6 and sensory abnormality in 3, while the study was completely normal in 10. Cystoscopy revealed normal findings in 17 cases, trabeculations in 21, inflammation in 20 and type 1 posterior urethral valves in 2. CONCLUSIONS: The incidence of upper tract changes and positive anatomical findings in children with voiding dysfunction is too low to justify routine radiological evaluation and cystoscopy. However, in those who present with a nonfebrile urinary tract infection there remains an important role for voiding cystourethrography. We do not recommend routine urodynamics in children with voiding disorder because this study does not change therapy or influence the final outcome. Thorough history and physical examination lead to the correct diagnosis and treatment in the majority of children. A focus on correcting faulty voiding behavior with the judicious administration of antibiotics and anticholinergic therapy leads to a favorable outcome in most cases.

Algorithms↗
PubMed2001

Polychlorinated biphenyl serum levels in pregnant subjects with diabetes.

OBJECTIVE: Polychlorinated biphenyls (PCBs) are persistent pollutants that are ubiquitous in the food chain; detectable amounts are in the blood of nearly everyone. Their effect on humans at background levels of exposure is an area of active investigation. Increased blood levels of dioxin (2,3,7,8-tetrachlorodibenzo-p-dioxin), a PCB-like compound, have recently been reported among subjects with diabetes, suggesting that PCB levels could be similarly elevated. To test this hypothesis, we examined a group of pregnant women whose serum PCB levels had been measured and whose diabetes status had been previously recorded. RESEARCH DESIGN AND METHODS: Using stored serum from a large birth cohort study, we conducted a cross-sectional study of 2,245 pregnant women, of whom 44 had diabetes (primarily type 1) and 2,201 were control subjects. RESULTS: The adjusted mean serum level of PCBs among the subjects with diabetes was 30% higher than in the control subjects (P = 0.0002), and the relationship of PCB level to adjusted odds of diabetes was linear. CONCLUSIONS: The possibility exists that PCBs and diabetes are causality related; alternatively, the pharmacokinetics of PCBs could be altered among patients with diabetes. At any event, if the association is replicated in other studies, increased serum levels of PCBs in subjects with diabetes or their offspring may put them at increased risk of PCB-induced changes in thyroid metabolism or neurodevelopment.

Adult↗
PubMed2001

Small intestinal submucosa as a urethral coverage layer.

PURPOSE: Urethrocutaneous fistula is the most common complication of hypospadias surgery. Numerous techniques have been used to decrease the incidence of this complication and the use of biocompatible materials in surgery has expanded the options in difficult situations. We hypothesized that porcine small intestinal submucosa may be used as a coverage layer after urethral surgery. We evaluated the histological changes associated with small intestinal submucosa when used as a coverage layer over the urethra in a rabbit model. METHODS AND METHODS: We performed urethral surgery in 16 New Zealand White rabbits divided into 4 animals each in groups 1-sham operation with penile degloving only, 2-penile degloving and small intestinal submucosa patch placement, 3-urethrotomy without a patch and 4-urethrotomy with a small intestinal submucosa patch. The graft edges were marked with permanent suture at surgery for later identification. All rabbits were maintained for 6 weeks before sacrifice. The urethra of each animal was then serially sectioned and examined histologically. RESULTS: Histological examination of animals with an small intestinal submucosa patch revealed a foreign body tissue reaction with an infiltrate of histiocytes, giant cells and lymphocytes in the area of graft placement. There was no histological evidence of remaining small intestinal submucosa patch in any sections. The urethral mucosa healed normally in all cases in which it was disrupted. There was no evidence of acute or chronic inflammation in any group 1 or 2 nonsmall intestinal submucosa animals and none in the animals with a small intestinal submucosa graft in areas other than the former graft site. There were also no urethrocutaneous fistulas in any of the 8 rabbits that underwent urethrotomy. CONCLUSIONS: Small intestine submucosa provides an adequate coverage layer in the rabbit penis after urethrotomy. Histologically the foreign material did not alter normal healing of the urethral mucosa, although it did appear to cause an infiltration of histiocytes, giant cells and lymphocytes. Small intestinal submucosa has previously been studied as a scaffold on which tissue may be remodeled or may regenerate. Our study shows that small intestinal submucosa did not interfere with normal tissue healing in this animal model. When used as a urethral coverage layer, it appears to provide extra tissue between the urethra and skin. Small intestinal submucosa may potentially decrease the incidence of urethrocutaneous fistula after urethral surgery.

Animals↗
PubMed2001

Exposure to persistent organochlorines among Alaska Native women.

OBJECTIVES: To report the levels of DDT, DDE, other chlorinated pesticides, and PCBs found in 131 Alaska Native women who had serum samples collected between 1980 and 1987 and to compare these levels to other published studies of DDE and PCB exposure among U.S. women. STUDY DESIGN: Review of data collected during a case-control study of the relationship between organochlorine chemicals and breast cancer. Data for case and control women were pooled in this analysis because case-control differences were found to be minimal and because serum samples pre-dated cancer diagnoses by 3 to 10 years. RESULTS: More than 99% of the women had detectable levels of p,p-DDE (mean 9.10 ng/mL or ppb). Mean total PCB level was 7.56 ppb. Levels of exposure varied by geographical location and ethnic identification, which maybe a reflection of dietary differences. Five of the organochlorines were detected in at least half of the study population. Results were recalculated using detection limits corresponding to other published studies of DDE and PCB levels in U.S. women. Alaska women had levels similar to those reported from New York women collected in the 1980s. We compared the PCB congener levels measured in Alaska Native women with levels reported in Arctic animals and found similar PCB congener profiles. The six most frequently detected contaminants in Alaska Natives were also detected in the marine mammal samples reported by Becker et al (5). CONCLUSIONS: Our study identified widespread Alaska Native exposure to organochlorines that originated outside of the Arctic, a finding also seen in other studies. Our results provide a reference baseline for exposure levels during the 1980s, but further research is necessary to assess temporal trends in exposure among Alaska Natives. Further, the need for national and international inter-laboratory standardization for testing for persistent organochlorines to facilitate comparisons between Alaska Natives and other American populations is clearly demonstrated.

Alaska↗
PubMed2001

Angiotensin type II receptor expression and ureteral budding.

PURPOSE: Deletion of the angiotensin type II receptor gene (Agtr2) in mice results in a spectrum of urinary tract anomalies similar to that in humans. The mechanism behind this anomalous development is poorly understood. We evaluated Agtr2 expression as it relates to normal and abnormal ureteral budding. MATERIALS AND METHODS: A total of 400 wild type mice were inspected at birth for gross evidence of a urinary tract anomaly. In addition, the urinary tracts of 30 wild type embryos were evaluated at 11.0/11.5 and 13.5 weeks of gestation. These embryos were examined for ureteral budding site via section and whole mount in situ hybridization with c-ret probe and Agtr2 expression via in situ hybridization with Agtr2 riboprobe. There were 740 newborn mice homozygous for the null mutation of Agtr2 also evaluated along with 55 angiotensin type II knockout embryos at the aforementioned gestational ages. RESULTS: All wild type newborn animals were grossly normal. Of the angiotensin type II knockout newborns 23 (3.1%) had gross abnormalities of the urinary tract at birth. The predominant finding was a duplicated collecting system associated with a hydronephrotic upper pole moiety. These duplicated collecting systems fulfilled the Meyer-Weigert law. Interestingly, 25 (59.5%) of the knockout embryos showed abnormal ureteral budding. However, in wild type embryos Agtr2 was expressed at this "ectopic" cranial site between the wolffian duct and metanephric mesenchyme. CONCLUSIONS: Although not the sole regulator, angiotensin type II receptor expression may have a role in the embryological development of the urinary tract by inhibiting aberrant ureteral budding. A defect in this inhibitory process appears to cause ectopic ureteral budding, and may subsequently lead to renal dysplasia and other congenital anomalies of the kidney and urinary tract.

Animals↗
PubMed2000

Quantitative detection of eight phthalate metabolites in human urine using HPLC-APCI-MS/MS.

Because of the ubiquity of phthalates and their potential role in increasing risk for cancer and reproductive dysfunction, the need for human exposure assessment studies is urgent. In response to this need, we developed a high-throughput, robust, sensitive, accurate, and precise assay for simultaneous measurement of trace levels of eight phthalate metabolites in human urine by HPLC-MS/MS. Human urine samples were processed using enzymatic deconjugation of the glucuronides followed by solid-phase extraction. The eluate was concentrated, and the phthalate metabolites were chromatographically resolved by reversed-phase HPLC, detected by APCI-tandem mass spectrometry, and quantified by isotope dilution. This selective analytical method permits rapid detection (7.7 min total run time) of eight urinary metabolites of the most commonly used phthalates with detection limits in the low nanagram per milliliter range. Assay precision was improved by incorporating 13C4-labeled internal standards for each of the eight analytes, as well as a conjugated internal standard to monitor deconjugation efficiency. This selective, sensitive, and rapid method will help elucidate potential associations (if any) between human exposure to phthalates and adverse health effects.

Calibration↗
PubMed2000

Organochlorine exposure and breast cancer survival.

Recent research suggests that exposure to organochlorines, such as dieldrin that possess estrogenic properties, may increase the risk of breast cancer by promoting growth of malignant cells. Whether this potential also affects malignant cells not eradicated by treatment, and thereby survival, is unknown. To evaluate this blood samples from female participants in the Copenhagen City Heart Study, Denmark, were analyzed for organochlorines. A total of 195 breast cancer cases, who each provided two blood samples that were taken in 1976-78 and 1981-83, respectively, were included in the survival analysis. Dieldrin had a significant adverse effect on overall survival and breast cancer specific survival (RR, 2.78, 95% CI, 1. 38-5.59, P trend < 0.01; RR, 2.61, 95% CI, 0.97-7.01, P trend < 0. 01). This association was strengthened when exposure was assessed as the average serum concentration of the two measurements. These findings suggest that past exposure to estrogenic organochlorines such as dieldrin may not only affect the risk of developing breast cancer but also the survival.

Adult↗
PubMed2000

[Organochlorine compounds and breast cancer--is there a connection between environmental pollution and breast cancer?].

Some organochlorine compounds may have weak oestrogenic effects and are therefore suspected of increasing the risk of breast cancer. The risk of breast cancer was assessed prospectively in relation to the serum concentration of several organochlorines. In all 240 women, who developed breast cancer between 1976 and 1993 were together with 477 breast cancer-free controls enrolled in a cohort-nested case-control study. The serum dieldrin concentration was associated with a significantly increased dose-related risk of breast cancer (Odds Ratio 2.05; 95% confidence interval 1.17-3.57; p for trend 0.01). There was no overall association between risk of breast cancer and DDT or polychlorinated biphenyls. The results support the hypothesis that exposure to oestrogenic organochlorines may increase the risk of breast cancer.

Breast Neoplasms↗
PubMed2000

Mass psychogenic illness attributed to toxic exposure at a high school.

BACKGROUND AND METHODS: Mass psychogenic illness may be difficult to differentiate from illness caused by bioterrorism, rapidly spreading infection, or toxic substances. We investigated symptoms attributed to exposure to toxic gas at a high school in Tennessee. In November 1998, a teacher noticed a 'gasoline-like' smell in her classroom, and soon thereafter she had a headache, nausea, shortness of breath, and dizziness. The school was evacuated, and 80 students and 19 staff members went to the emergency room at the local hospital; 38 persons were hospitalized overnight. Five days later, after the school had reopened, another 71 persons went to the emergency room. An extensive investigation was performed by several government agencies. RESULTS: We were unable to find a medical or environmental explanation for the reported illnesses. The persons who reported symptoms on the first day came from 36 classrooms scattered throughout the school. The most frequent symptoms (in this group and the group of people who reported symptoms five days later) were headache, dizziness, nausea, and drowsiness. Blood and urine specimens showed no evidence of carbon monoxide, volatile organic compounds, pesticides, polychlorinated biphenyls, paraquat, or mercury. There was no evidence of toxic compounds in the environment. A questionnaire administered a month later showed that the reported symptoms were significantly associated with female sex, seeing another ill person, knowing that a classmate was ill, and reporting an unusual odor at the school. CONCLUSIONS: The illness attributed to toxic exposure had features of mass psychogenic illness - notably, widespread subjective symptoms thought to be associated with environmental exposure to a toxic substance in the absence of objective evidence of an environmental cause. Alleviation of the anxiety surrounding an episode of mass psychogenic illness requires prompt recognition and a detailed investigation.

Disease Outbreaks↗
PubMed2000

The role of hypercalciuria in a subgroup of dysfunctional voiding syndromes of childhood.

PURPOSE: Idiopathic hypercalciuria is believed to be the cause of a variety of urinary tract complaints in clinical pediatrics, including urinary frequency, urgency, and/or dysuria, often associated with gross or microscopic hematuria. In children noncalculous manifestations of idiopathic hypercalciuria are reportedly more common than urolithiasis. We determine the use of the calcium-to-creatinine ratio for the evaluation of different subsets of functional voiding disorders. MATERIALS AND METHODS: We retrospectively evaluated 288 patients with functional voiding disorders during the last 8 years. Patients presenting with isolated urinary tract infection were not included in the study. A thorough history with emphasis on voiding patterns was elicited and a routine urinalysis was performed in all patients. Patients were divided into 5 groups of 22 with total gross hematuria and dysfunctional voiding pattern, 102 with microhematuria and dysfunctional voiding pattern, 66 with isolated childhood daytime frequency, 45 with the isolated dysuria syndrome and 53 with combined childhood frequency-urgency-dysuria syndrome. The season at presentation was noted to determine a seasonal pattern. In 149 patients urine was evaluated for a spot calcium-to-creatinine ratio. RESULTS: Mean age of the 95 (33%) males and 193 (67%) females was 6.1 years (range 2 to 14) and mean duration of symptoms was 10 months (1 week to 10 years). The incidence of idiopathic hypercalciuria was 28% in cases with gross hematuria and dysfunctional voiding, 30% with microscopic hematuria and dysfunctional voiding, 21% with pure childhood daytime frequency, 22% with pure dysuria, and 28% with frequency, urgency and dysuria. The patients were treated predominantly with behavioral therapy, correction of faulty voiding habits, anticholinergics and minor diet modification in some. Mean followup of 6.5 months (range 1 month to 10 years) was available for 153 patients (53%). Resolution of symptoms along with marked improvement in voiding habits was noted in 136 (89%) patients, moderate improvement in 10 (6.5%) and persistent symptoms with minimal improvement in 7 (4.5%). Treatment with thiazides was used in only 6 (2%) patients who had intractable symptoms and a markedly elevated urine calcium-to-creatinine ratio of whom 5 responded favorably. CONCLUSIONS: Idiopathic hypercalciuria may have a significant role in cases of functional voiding disorders. It affects the different subsets of voiding disorders with remarkable consistency but the exact mechanism remains unknown. Although a significant number of patients with voiding dysfunction have an elevated calcium-to-creatinine ratio, the majority respond to standard behavioral therapy and pharmacotherapy in the form of anticholinergics, and treatment directed toward hypercalciuria is not required in most cases.

Adolescent↗