Management of urethrocutaneous fistula following hypospadias repair

Urethrocutaneous fistulas complicating hypospadias repair appear a common problem. There appears less data in the literature regarding the risk and management of recurrent fistulas. A retrospective review of urethrocutaneous fistulas complicating hypospadias repair was performed to evaluate their aetiology, management and outcome. Between 1993 and 2003, 1,753 patients had a hypospadias repair at our institution. Overall 123 (7%) boys developed a fistula, although detailed information was available on 117 patients only. Median age was 3.5 years at the time of fistula repair; 13% had anterior, 57% had middle and 30% had posterior hypospadias. The most common primary surgical procedure was a Durham Smith two-stage repair in 29% (n = 34), followed by a Tubularised Incised Plate urethroplasty in 19% (n = 22) and an Onlay in 14% (n = 16). Thirty-one (27%) patients developed a recurrent fistula, 9 (29%) of which recurred following a second repair. None recurred after a third repair. The risk of a recurrent fistula after an initial distal fistula repair was 12.5% and after a posterior fistula was 62% (chi(2) = 15.4, P = 0.001). Use of a stent, suture type, numbers of fistula and closure attempts did not influence the recurrence rate. Undiagnosed distal obstruction was thought to be related to 27 of 117 first fistula repairs (23%) and 4 of 31 second fistula repairs (13%). The risk of recurrent urethrocutaneous fistula was increased in those boys with a posterior fistula, following a simple repair or when there was evidence of distal urethral obstruction.

Evaluation of the NK2 homeobox 1 gene (NKX2-1) as a Hirschsprung's disease locus

Hirschsprung's disease (HSCR, colonic aganglionosis) is an oligogenic entity that usually requires mutations in RET and other interacting loci. Decreased levels of RET expression may lead to the manifestation of HSCR. We previously showed that RET transcription was decreased due to alteration of the NKX2-1 binding site by two HSCR-associated RET promoter single nucleotide polymorphisms (SNPs). This prompted us to investigate whether DNA alterations in NKX2-1 could play a role in HSCR by affecting the RET-regulatory properties of the NKX2-1 protein. Our initial study on 86 Chinese HSCR patients revealed a Gly322Ser amino acid substitution in the NKX2-1 protein. In this study, we have examined 102 additional Chinese and 70 Caucasian patients and 194 Chinese and 60 Caucasian unselected, unrelated, subjects as controls. The relevance of the DNA changes detected in NKX2-1 by direct sequencing were evaluated using bioinformatics, reporter and binding-assays, mouse neurosphere culture, immunohistochemistry and immunofluorescence techniques. Met3Leu and Pro48Pro were identified in 2 Caucasian and 1 Chinese patients respectively. In vitro analysis showed that Met3Leu reduced the activity of the RET promoter by 100% in the presence of the wild-type or HSCR-associated RET promoter SNP alleles. The apparent binding affinity of the NKX2-1 mutated protein was not decreased. The Met3Leu mutation may affect the interaction of NKX2-1 with its protein partners. The absence of NKX2-1 expression in mouse but not in human gut suggests that the role of NKX2-1 in gut development differs between the two species. NKX2-1 mutations could contribute to HSCR by affecting RET expression through defective interactions with other transcription factors.

Diagnostic accuracy of surgeon-performed focused abdominal sonography (FAST) in blunt paediatric trauma

AIM

To study the diagnostic accuracy and clinical efficacy of surgeon-performed focused abdominal sonography (FAST) in paediatric blunt abdominal trauma (BAT).

MATERIALS AND METHOD

This was a prospective, single blinded study conducted at The Children's Hospital at Westmead Sydney (CHW). All patients with BAT that justified a trauma call activated on presentation to the Emergency Department (ED) had a FAST performed by the Trauma Fellow. The attending surgical team was blinded to the result of the FAST. An independent radiologist reviewed the FAST pictures, and the findings were compared with computerised tomography (CT), ultrasound (US), laparotomy and the clinical outcome of the patient. Sensitivity, specificity and predictive values were calculated.

RESULTS

A total of 85 patients (39 M; 26 F) were enrolled in the study between February 2002 and January 2003. The age ranged between 4 months and 16 years. The mean Injury Severity Score (ISS) was 6 (range 1-38). FAST was performed in a mean time of 3 min. Inter-rater agreement was 96%. FAST was positive in nine as confirmed by a CT scan of the abdomen. Three patients underwent laparotomy, two for bowel injuries and one for a Grade III liver laceration. Of the remaining 76, 19 had a CT, which showed evidence of intra-abdominal injury in seven patients. There were two false negative studies resulting in a sensitivity of 81%, specificity of 100%, negative predictive value of 97%, positive predictive value of 100% and an accuracy of 97%.

CONCLUSIONS

Surgeon-performed FAST for BAT was safe and accurate with a high specificity. It would seem a potentially valuable tool in the evaluation of paediatric blunt trauma victims for free fluid within the peritoneal cavity.

Blunt traumatic diaphragmatic injuries in children

Diaphragmatic injuries following blunt trauma are rare. From January 1988 to February 2002 eight children were treated at the Children's Hospital at Westmead for diaphragmatic injury. Male to female ration was 5:3. Motor vehicle crashes were the most common cause. The injury was left-sided in four, right sided in three and central in one. Initial plain radiograph and computerised tomography detected the injury in 50% of cases. Laparotomy, contrast study and autopsy identified the rupture in one each. Associated injuries were present in all cases. Seven children had laparotomy and repair of the diaphragmatic rupture. The commonest site of rupture was posterolateral (37.5%). Diagnosis was delayed in two cases. There were two deaths (25% mortality) in the series, both due to associated injuries. Although rare, diaphragmatic rupture must be considered in any child with thoracoabdominal injury. Diagnosis may be difficult and require extensive investigation. Mortality usually results from associated injuries.

Pancreatic trauma in children

BACKGROUND/PURPOSE

The aim of this study was to determine the etiology, associated injuries, and outcome of children with pancreatic injuries.

METHODS

A retrospective review was conducted of children under 16 years with pancreatic trauma admitted to the Children's Hospital at Westmead (CHW) from January 1983 to September 2002. Deaths were reported to the New South Wales Paediatric Trauma Death Registry (State Registry) from January 1988 to September 2002.

RESULTS

Sixty-five cases were identified: 46 patients were admitted to CHW, and 22 deaths were reported to the State Registry (including 3 deaths at CHW). The median age was 6 years (range, 1 to 14 years). Boys accounted for 60% (n = 40) of cases, decreasing to 50% (n = 11) of those that died. Motor vehicle injuries (MVI) were the most common mechanism, accounting for 40% of survivors and 77% of those who died. Children were restrained incorrectly in 48% of all cases and in 67% of those who died. Significantly more children who died had head, chest, and abdominal visceral injuries, compared with those who survived. Death occurred as a result of head injuries in 68%, with only 3 deaths directly attributed to pancreatico-duodenal injuries.

CONCLUSIONS

Pancreatic injuries remain uncommon in children. The most frequent mechanism was MVI, with incorrect use of passenger restraints an important contributing factor. Whereas mortality was mainly caused by other injuries, 3 deaths were directly attributable to pancreato-duodenal trauma.

Children under 5 years presenting to paediatricians with near-drowning

OBJECTIVE

To characterize children aged under 5 years who present to paediatricians following near-drowning and the circumstances surrounding the event, identify high-risk groups and document short-term outcome.

METHODOLOGY

Monthly notifications to the Australian Paediatric Surveillance Unit (an active, national surveillance system) between 1994 and 1996. Collection of additional case information from reporting doctors by postal questionnaire.

RESULTS

All 169 reported cases of near-drowning were admitted to hospital (mean (SD) stay 6 (17) days) and 15% required intensive care (mean (SD) stay 19 (32) days). The mean (SD) age for near drowning was 26 (13) months and 22% children were aged between 12 and 18 months. Males predominated (1.6:1) and 69 (41%) of episodes occurred in summer (December - February). The majority (82%) of near-drownings occurred in the child's home, usually in a swimming pool or bath. Children who nearly drowned at home were significantly younger than those who nearly drowned in natural waterways or public pools. Neurological damage at discharge following near-drowning was reported in 7%.

CONCLUSIONS

Children reported in this national case series represent the severe end of the spectrum of those who nearly drown, as indicated by their presentation to a paediatrician, universal hospitalization and adverse neurological outcome. The home is the site of most near-drownings and males and toddlers were at particular risk. Unimpeded access to pools and lack of supervision were identified as potentially modifiable factors for prevention. The study suggests the need for additional community education regarding the risks of near-drowning and for further research on long-term neuro-developmental outcomes following near-drowning.

Penetrating injuries in children: is there a message?

OBJECTIVES

To determine the frequency, management and outcome of penetrating trauma in children.

METHODS

A retrospective review of penetrating injuries in children under 16 years of age admitted to the Children's Hospital at Westmead (CHW), and deaths reported to the New South Wales Paediatric Trauma Death (NPTD) Registry, from January 1988 to December 2000. Patient details, circumstances of trauma, injuries identified, management and outcome were recorded.

RESULTS

Thirty-four children were admitted to the CHW with penetrating injuries during the 13-year period. This represented 0.2% of all trauma admissions, but 3% of those children with major trauma. The injury typically involved a male, school-age child that fell onto a sharp object or was assaulted with a knife or firearm by a parent or person known to them. Twenty-five children (75%) required operative intervention for their injuries and 14 survivors (42%) suffered long-term morbidity. Thirty children were reported to the NPTD Registry over the same interval, accounting for 2.3% of all trauma deaths in New South Wales. Of these, a significant minority was injured by falls from a mower or a tractor towing a machine with blades.

CONCLUSIONS

Penetrating injuries are uncommon, but cause serious injury in children. There are two clear groups: (i) those dead at the scene or moribund on arrival, in whom prevention must be the main aim; and (ii) those with stable vital signs. Penetrating wounds should be explored in the operating theatre to exclude major injury. Young children should not ride on mowers or tractors.

Duodenal atresia with vascular rings and subglottic stenosis

This case report of duodenal atresia associated with a vascular ring and subglottic stenosis raises some interesting issues of management.

Congenital lobar emphysema: Like father, like son

Congenital lobar emphysema (CLE) is an uncommon cause of progressive respiratory distress that typically presents in the first few days of life. There has been a previous report of CLE in a mother and daughter. The authors describe 2 cases involving the right upper and middle lobes in a father and son secondary to relative deficiency of the bronchial cartilage. This provides additional evidence for inherited factors in the etiology of CLE.

Isolated and multisystem hepatic trauma in children: the true role of non-operative management

We retrospectively reviewed children with hepatic injuries (HI) admitted to our institutions from January 1982 to December 1999. Specific comparison was made of isolated (IHT) and multisystem hepatic trauma (MHT). Over the 18-year period 127 patients were identified with HI, 91 (71%) with MHT and 36 with IHT. The median age was 8 years (range 13 months to 14 years). Motor vehicle injury was the most common mechanism in both groups, but bicycle injuries were more common in IHT ( P<0.001). Shock ( P=0.02), the requirement for blood transfusion ( P<0.001), and operative intervention for the HI ( P=0.001) were all significantly more common in MHT. The distribution of liver injury grades was similar between the two groups. Twenty-two (17.3%) children died and in 18 the HI was the main cause or contributed significantly. There were 19 and 3 deaths in the MHT and IHT groups, respectively, a difference that was not significant. After excluding children with minor HI, 27 (39%) required operative intervention within 24 h of their injury. This suggests that the high success rate for non-operative management of HIs in the literature may have been biased by the inclusion of a significant proportion of subclinical injuries.

Laser Doppler imaging prediction of burn wound outcome in children

The ability of laser Doppler imaging (LDI) to evaluate burn depth in children was investigated. Fifty-seven patients were prospectively studied over a 10-month period. Each patient was clinically assessed, photographed and independently scanned between 36 and 72 h of the burn. Patients were reviewed until wound healing had occurred within 12 days or skin grafting had been performed. The median age was 1 year and 10 months (range 5 months to 15 years and 8 months). The median body surface area burnt was 7.0% (range 0.5-30%). In 30 patients, the burn did not heal within 12 days, 17 of which were grafted. Clinical examination correctly determined 66% of deep partial or full thickness burns between 36 and 72 h of injury compared to 90% using LDI. The LDI was also more specific; correctly diagnosing 96% of superficial partial thickness burns as opposed to 71% on clinical examination. Moderate degrees of movement did not appear to limit the accuracy of the scan.

Horse-related injuries in children

OBJECTIVES

To identify the frequency, spectrum and outcome of horse-related injuries in children.

DESIGN AND SETTING

Retrospective case series of horse-related injuries in children admitted to the Children's Hospital at Westmead (CHW) from January 1988 to December 1999, the John Hunter Children's Hospital (JHCH) from January 1991 to December 1997 and deaths reported to the New South Wales Paediatric Trauma Death (NPTD) Registry from January 1988 to December 1999.

MAIN OUTCOME MEASURES

Circumstances of injury; helmet use; adult supervision; type and number of injuries identified.

RESULTS

232 children were admitted with horse-related trauma, 97 to the CHW over 12 years and 135 to JHCH over seven years, with one death at each hospital. There were six deaths reported to the NPTD Registry over 12 years. The median age was 11 years (range, 1-17). Girls accounted for 65% of those injured and 75% of children were injured while riding. Falls caused the injury in 76.3% of cases. Head and upper-limb trauma accounted for 216 of the injuries (73%). Five out of six children with severe head injuries died. In the CHW group, helmet use was documented in only 24 riders (38%) and adult supervision in 22 (22.9%).

CONCLUSIONS

Horse-related trauma accounts for a considerable number of deaths and injuries in children in NSW. The use of a Standards-approved helmet for riding or horse-related activities might have decreased the severity of head injuries.

Gastroschisis reduction under analgesia in the neonatal unit

PURPOSE

The authors present their experience of reduction of gastroschisis in infants in the ward with analgesia and without anesthesia.

METHODS

Prospective data were collected on 35 infants born with gastroschisis from 1999 to 2001. Ward reduction (WR) was not attempted in infants with obvious gut atresia, perforated or ischemic bowel, or systemic instability.

RESULTS

Ward reduction was attempted in 29 of the 35 infants and was successful in 25. There were no deaths or major morbidity in those that underwent ward reduction. Ventilation was required in 2, and line sepsis occurred in 4. Umbilical hernia was seen in 7; all but 1 were treated conservatively.

CONCLUSIONS

In gastroschisis, ward reduction under analgesia is safe if strict selection criteria are adhered to. Postreduction ventilation is avoided in the majority.

Noncervicofacial atypical mycobacterial lymphadenitis in childhood

BACKGROUND/PURPOSE

Atypical mycobacterial (AM) lymphadenitis is common in children but rarely occurs outside the cervicofacial region. The authors report their experience in the diagnosis and management of noncervicofacial AM lymphadenitis.

METHODS

A retrospective review was conducted of cases diagnosed at our institution between January 1976 and December 1999, based on positive culture of atypical mycobacteria or consistent histology with supportive skin testing.

RESULTS

Thirty-seven patients were identified over the 23-year review period. The median age was 4.3 years (range, 8 months to 13 years and 5 months), with 19 boys and 17 girls. The median duration of symptoms was 4 weeks, and the most commonly affected sites were the inguinal region (n = 17), axilla (n = 8), and lower limb (n = 6). Preceding local trauma was described in 10 patients and a viral illness in 4. Laboratory culture for atypical mycobacteria was positive in 22, and skin testing suggestive in 21 and equivocal in 2. Treatment was by excision in 28 and drainage with or without curettage in 9. At a median follow-up of 19.7 months, disease had recurred in 4 patients, none of whom had been treated initially by excision.

CONCLUSIONS

Atypical mycobacterial infection is an uncommon cause of noncervicofacial lymphadenitis in children. It typically presents with a 4-week history of painless regional lymphadenopathy that may follow penetrating trauma. If untreated, the overlying skin becomes involved with a violaceous discoloration, and ulceration may occur. Definitive treatment involves complete surgical excision, preferably before suppuration extending beyond the involved lymph nodes.

HOSE: an objective scoring system for evaluating the results of hypospadias surgery

OBJECTIVE

To determine the accuracy and utility of a scoring system designed to allow an objective appraisal of the outcome of hypospadias repair, based on evaluating meatal location, meatal shape, urinary stream, straightness of erection, and the presence and complexity of any complicating urethral fistula.

PATIENTS AND METHODS

Twenty patients (median age 23 months) were randomly selected and reviewed at a median of 8.9 months after their hypospadias repair. Two paediatric surgeons, a nurse and one of the child's parents independently assessed each patient using the "hypospadias objective scoring evaluation" (HOSE) system. The results were collated and the level of interobserver variation assessed using the weighted kappa test.

RESULTS

The mean weighted kappa was 0.66, indicating good agreement among observers. The level of agreement was highest between surgeon and nurse at 0.70, but remained good between surgeon and parent, at 0.65.

CONCLUSIONS

Interobserver variation using the HOSE system was minimal, supporting its use as an objective outcome measure after hypospadias surgery, and facilitating an impartial evaluation of operations used in correcting hypospadias.

Mechanisms for the development of esophageal atresia

BACKGROUND

There is no universally accepted theory to explain esophageal embryology and the abnormal development that produces esophageal atresia.

METHODS

The impact of Adriamycin administration on the pathogenesis of esophageal atresia was studied in the rat model of VATER association, from embryonic day (ED) 10 to ED 13.

RESULTS

Tissues in the ED10 Adriamycin-exposed embryos displayed less cell proliferation as shown by the reduced population of MIB-5-labelled cells. Cell apoptosis that is characteristic of the normal ED 12 lateral epithelial folds of the foregut (the prospective site of tracheoesophageal septation) was absent in the foregut of the Adriamycin-exposed embryo. Histologic examination of the ED 11-exposed embryo showed the presence of abnormal notochord that was stretched, split, or tethered to the foregut. This contrasts with the normal embryo in which the notochord was localized in close vicinity of the ventral part of the neural tube and separated from the foregut by ample amount of mesenchyme. The abnormal localization of the notochord was accompanied by the lack of down-regulation of the sonic hedgehog (Shh) activity in the prospective site of future tracheoesophageal separation in the exposed ED 12 embryo.

CONCLUSION

The authors proposed that the ectopic location of the notochord leads to the disruption in Shh signalling that may underpin the development of esophageal atresia.

Facial fractures in children

OBJECTIVE

To determine the pattern of injury of facial fractures in children, the relative contribution of plain radiography and CT scanning in the diagnosis of these injuries, and factors leading to delayed diagnosis.

DESIGN

Retrospective case note review.

PARTICIPANTS

All children with facial fractures identified using the trauma and medical record databases at our institution.

RESULTS

Forty-six children with 59 facial fractures presented over a 4-year, 2-month period from November 1995 to December 1999. The median age was 10 years, with a range from 1 to 14. There was a 2-to-1 male-to-female sex ratio. A motor vehicle accident (MVA) involving a child as passenger, pedestrian, or cyclist accounted for 63% of cases. In seven of these, the child was either a front seat passenger or inappropriately restrained for their age and size. In all but one case, the presence of a fracture was associated with an overlying laceration, abrasion, or significant soft tissue edema. Initial examination and plain radiologic assessment by a pediatric clinician led to diagnostic delay in nine children. Facial CT was performed in 38 children, and all results were positive. Twenty-six patients required operative intervention for their facial fracture. Associated injuries, particularly of the head and limbs, were present in all but six patients.

CONCLUSIONS

Facial fractures were uncommon overall but occurred more frequently in children with major trauma. Plain facial radiographs provided limited additional diagnostic information to careful clinical examination and often fail to detect or clearly define a facial fracture in children. In the correct clinical setting, a facial CT scan allows accurate diagnosis of the injury and can reveal previously unsuspected additional fractures.

Urethral trauma in children

We report our 12-year experience in the management of urethral injuries in nine children, six boys and three girls. The most common mechanisms of injury were motor vehicle accidents, followed by straddle injuries. All the injuries in boys involved the anterior urethra, and in girls the proximal or mid-urethra. There were associated injuries in five, including three pelvic fractures. All children were investigated with a retrograde urethrogram. Four were treated non-operatively with insertion of a urethral catheter. Of the remaining five, one had drainage of a penile haematoma, one cystourethroscopy, two insertion of urinary and suprapubic catheters, and one open cystotomy and passage of a guide wire with antegrade passage of a urethral catheter. Complications included one urinary tract infection, one urethral fistula, one urethrovaginal fistula, and two urethral strictures. Final outcome was satisfactory in all nine children.

Endothelins control the timing of Schwann cell generation in vitro and in vivo

Schwann cell precursors, derivatives of the neural crest, generate Schwann cells in a process that is tightly timed, well characterized, and directly controlled by axonal signals, in particular beta-neuregulins. Here we provide evidence that endothelins (ETs) are also important for survival and lineage progression in this system. We show that ETs promote rat Schwann cell precursor survival in vitro without stimulation of DNA synthesis. Using ET receptor agonists and antagonists, we demonstrate that this action of ET is mediated by the ET(B) receptor. RT-PCR reveals the presence of ET and ET receptor mRNA in the developing rat PNS. We showed previously that in vitro beta-neuregulins promote the generation of Schwann cells from precursors on schedule and that this process can be accelerated by fibroblast growth factor 2. Here we show that although ETs promote long-term precursor survival the transition of precursors to Schwann cells is delayed. Moreover, ETs block the maturation effects of beta-neuregulins. In spotting lethal rats, in which functional ET(B) receptors are absent, we find accelerated expression of the Schwann cell marker S100 in developing nerves. These observations indicate that complex growth factor interactions control the timing of Schwann cell development in embryonic nerves and that ETs act as negative regulators of Schwann cell generation.

Driveway motor vehicle injuries in children

OBJECTIVES

To describe the frequency, nature and outcome of driveway injuries in children.

DESIGN

Retrospective case series of driveway-related injuries in children under 16 years of age admitted to the New Children's Hospital (NCH), New South Wales, from November 1995 to February 2000, and deaths reported to the New South Wales Paediatric Trauma Death (NPTD) Registry from January 1988 to December 1999.

MAIN OUTCOME MEASURES

Circumstances of injury; type and number of injuries identified.

RESULTS

42 children were admitted to our institution with driveway-related injuries over four years and four months. These represent 12% of all children admitted with pedestrian motor vehicle injuries. Fourteen deaths (including one of the children admitted to NCH) were reported to the NPTD Registry over 12 years, accounting for 8% of all paediatric pedestrian motor vehicle deaths reported to the registry. Typically, the injury involved a parent or relative reversing a motor vehicle in the home driveway over a toddler or preschool-age child in the late afternoon or early evening. Four-wheel-drive or light commercial vehicles were involved in 42% of all injuries, although they accounted for just 30.4% of registered vehicles in NSW. These vehicles were associated with a 2.5-times increased risk of fatality. In 13 of the 14 deaths, the cause was a severe head injury not amenable to medical intervention.

CONCLUSIONS

Driveway injuries in children account for a significant proportion of paediatric pedestrian motor vehicle injuries and deaths in NSW. Prevention represents the only effective approach to reducing deaths from this cause.

Clinical review of the 'Snodgrass' hypospadias repair

BACKGROUND

Snodgrass first described the tubularized, incised plate (TIP) urethroplasty for distal hypospadias repair in 1994 based on the concept of hingeing the incised urethral plate. The use of this technique allows a vertically orientated glanular meatus to be produced. A retrospective review of patients who had this procedure for the primary repair of distal hypospadias at New Children's Hospital was performed to objectively assess the cosmetic and functional outcomes of this technique.

METHODS

All patients having a TIP urethroplasty for the primary repair of distal hypospadias between 1996 and 1998 were requested to attend for review in an independent clinic. The parents were interviewed and the patient was examined to determine meatal location, meatal size, glanular configuration, urinary stream, straightness of erections, cosmesis, and the presence or absence of cutaneous sinus tracts or a urethral fistula.

RESULTS

Sixty patients were identified. Forty-nine were reviewed in person, 10 were reviewed by telephone and one could not be traced. The median age at surgery was 13 months (range: 6-144 months), with a median follow up of 27 months (range: 2-33 months). A glanular meatus was achieved in 57 patients (97%) and a conical glanular configuration was achieved in 58 patients (98%). The urinary stream and erections were straight in 54 (89%) and 58 patients (98%), respectively. Suture sinus tracts were present in 14 (24%) patients. Six patients (10%) developed a urethral fistula and three (5%) developed meatal stenosis. A good or satisfactory final cosmetic and functional result was achieved in 58 patients (98%).

CONCLUSIONS

The results of TIP urethroplasty are satisfactory at New Children's Hospital with the benefit of a cosmetic final outcome similar to a circumcised penis.

Frequency of RET mutations in long- and short-segment Hirschsprung disease

Hirschsprung disease, or congenital aganglionic megacolon, is a genetic disorder of neural crest development affecting 1:5,000 newborns. Mutations in the RET proto-oncogene, repeatedly identified in the heterozygous state in both long- and short-segment Hirschsprung patients, lead to loss of both transforming and differentiating capacities of the activated RET through a dominant negative effect when expressed in appropriate cellular systems. The approach of single-strand conformational polymorphism analysis established for all the 20 exons of the RET proto-oncogene, and previously used to screen for point mutations in Hirschsprung patients allowed us to identify seven additional mutations among 39 sporadic and familial cases of Hirschsprung disease (detection rate 18%). This relatively low efficiency in detecting mutations of RET in Hirschsprung patients cannot be accounted by the hypothesis of genetic heterogeneity, which is not supported by the results of linkage analysis in the pedigrees analyzed so far. Almost 74% of the point mutations in our series, as well as in other patient series, were identified among long segment patients, who represented only 25% of our patient population. The finding of a C620R substitution in a patient affected with total colonic aganglionosis confirms the involvement of this mutation in the pathogenesis of different phenotypes (i.e., medullary thyroid carcinoma and Hirschsprung). Finally the R313Q mutation identified for the first time in homozygosity in a child born of consanguineous parents is associated with the most severe Hirschsprung phenotype (total colonic aganglionosis with small bowel involvement).

Small bowel injuries in children

OBJECTIVE

To determine the common features of small bowel injury (SBI) in childhood and the consequences of delayed diagnosis.

METHODOLOGY

A retrospective case review was performed of children with traumatic SBI between January 1988 and November 1999.

RESULTS

Twenty-eight patients were identified with SBI. Road trauma accounted for 71% of them. Tachycardia was present on admission in 82% of patients with SBI including all but one of the intestinal perforations. SBI was associated with a Chance fracture of the lumbar spine in three patients (11%). An abdominal computed tomography scan with intravenous contrast was abnormal in all patients with a perforation or mesenteric tear. Diagnosis was delayed in six patients, one of whom died as a result of sepsis from a small bowel perforation.

CONCLUSIONS

Persistent tachycardia with an appropriate mechanism of injury following blunt abdominal trauma requires active exclusion of SBI. Delayed diagnosis is associated with significant morbidity and mortality.

Children at play: the death and injury pattern in New South Wales, Australia, July 1990-June 1994

OBJECTIVES

To describe and to understand the pattern of play-related deaths and injury (excluding organized sports) among children in New South Wales (NSW), Australia.

METHODOLOGY

This study utilized a state-wide prospective surveillance data collection of paediatric traumatic deaths and injuries at the Royal Alexandra Hospital for Children. Deaths and injury cases were selected from the NSW Trauma Death Registry and Childsafe NSW database. Information including basic demographics, the surrounding circumstances of death and injury incidents, and the required treatment was collected.

RESULTS

There were 30 play-related deaths and 92 drownings over the 4-year period. The male to female ratio was about 2:1. Excluding drowning, which has been reported elsewhere, and sports, the leading causes of play-related deaths were burns (eight) and asphyxiation (eight). An average of 6444 presentations to the emergency departments per year were recorded with sex ratio and age distribution pattern similar to the deaths. The home was the most common place (55.5%) of play-related injury, specifically the living and sleeping area. Falls, both under and above 1 metre, were the most common causes of injury (50.9%). The leading mechanism was cuts and lacerations (21.2%). Nearly one-third (32.7%) of all injuries were to the head, with face, cheek, forehead and scalp as the most common injured body part. Significant associations between place of injury, injured body parts and age were observed.

CONCLUSIONS

Play-related injury is common among children, and in some cases causes severe injury and death. To tackle the problem of play-related deaths and injuries, a holistic approach is suggested. This includes the provision of a safe environment, supervision by parents, education of children and detailed data collection.

Dose response relationship between adriamycin and birth defects in a rat model of VATER association

BACKGROUND/PURPOSE

The aim of this study was to reproduce the animal model of esophageal atresia and the VATER association. The purpose was a dose response analysis of Adriamycin teratogenicity in the rat and comparison of these anomalies with the human VATER association.

METHODS

Twenty time-mated Sprague-Dawley rats received intraperitoneal Adriamycin (dose range, 0 to 2.5 mg/kg/d) for 4 consecutive gestational days E6 to E9. The embryos were harvested on day E21, inspected, weighed, and dissected with a binocular dissecting microscope. Statistical analysis was performed with exact chi2.

RESULTS

Threshold doses of 1.25 and 1.5 mg/kg/d Adriamycin produced renal and gastrointestinal anomalies, respectively (exact chi2, P < .00001). In doses below 1.25 mg/kg/d Adriamycin, no anomalies were seen, and in above-threshold doses, the frequency of anomalies rose sharply as the dose increased. At 2.25 mg/kg/d of Adriamycin all embryos were abnormal, and Adriamycin at 2.5 mg/kg/d led to resorption of all embryos.

CONCLUSIONS

Adriamycin induced esophageal atresia, and VATER in the rat is a reproducible model that has many similarities to the VATER anomalies in the human. There is a relationship between dose and the frequency as well as severity of anomalies. Further studies of this model are likely to provide information relevant to the understanding of this human congenital disease.

The impact of work related trauma on the psychological health of nursing staff: a cross sectional study

This study aims to investigate the effects of work-related trauma exposure on the health of nursing staff in hospitals. The survey was conducted using a randomised sample of 314 nurses. Half (52.2%, n = 189) of staff surveyed had multiple exposures to different kinds of trauma. Results on the General Health Questionnaire (GHQ) and Beck's Depression Inventory--Revised (BDI-R) suggested that nearly 40% of staff experienced poor health, while nearly 10% experienced moderate to severe depression. Results of the logistic analyses, after adjusting for confounders, suggested that high and long term trauma exposure is detrimental to the mental health of nurses. These findings indicate that hospital nursing staff, in particular those who have high exposure to trauma, are in urgent need of support services such as debriefing and counselling.

Hirschsprung disease, microcephaly, mental retardation, and characteristic facial features: delineation of a new syndrome and identification of a locus at chromosome 2q22-q23

We have identified six children with a distinctive facial phenotype in association with mental retardation (MR), microcephaly, and short stature, four of whom presented with Hirschsprung (HSCR) disease in the neonatal period. HSCR was diagnosed in a further child at the age of 3 years after investigation for severe chronic constipation and another child, identified as sharing the same facial phenotype, had chronic constipation, but did not have HSCR. One of our patients has an interstitial deletion of chromosome 2, del(2)(q21q23). These children strongly resemble the patient reported by Lurie et al with HSCR and dysmorphic features associated with del(2)(q22q23). All patients have been isolated cases, suggesting a contiguous gene syndrome or a dominant single gene disorder involving a locus for HSCR located at 2q22-q23. Review of published reports suggests that there is significant phenotypic and genetic heterogeneity within the group of patients with HSCR, MR, and microcephaly. In particular, our patients appear to have a separate disorder from Goldberg-Shprintzen syndrome, for which autosomal recessive inheritance has been proposed because of sib recurrence and consanguinity in some families.

Congenital central hypoventilation syndrome and Hirschsprung's disease

Five cases of the Hirschsprung's disease-congenital central hypoventilation syndrome (CCHS) association are presented and 41 other published cases reviewed. These children have a distinct pattern of associated features, an equal sex incidence, and a characteristic spectrum of disease severity which suggests that the condition is genetically distinct from other cases of Hirschsprung's disease. While approximately 1.5% of Hirschsprung's disease patients, and 10% of those with total colonic aganglionosis, will have CCHS, up to 50% of CCHS patients will have Hirschsprung's disease. Approximately 20% of CCHS/Hirschsprung patients will also have neuroblastoma or ganglioneuroma, usually multiple. Abnormalities of the eye and autonomic nervous system are also common. The ventilatory abnormality is usually evident on the first day of life. The aganglionosis is also severe, with more than half (59%) of the patients having aganglionosis extending into the small bowel.

Hirschsprung's disease, colonic atresia, and absent hand: a new triad

Colonic atresia (CA) has been reported in association with Hirschsprung's Disease (HSCR) on 11 previous occasions. In most reported cases the atresia has involved the right side of the colon; but in this, the twelfth case report, the atresia involved the left side of the colon, with aganglionosis of the entire distal gut. In addition, the child had an absent hand. The authors believe that this triad has not been reported previously. The literature is reviewed, and possible mechanisms are discussed.

Childhood drowning in New South Wales 1990-1995: a population-based study

OBJECTIVE

To review the circumstances of children drowning in New South Wales (NSW), 1990-1995, and to analyse trends.

DESIGN

The NSW Paediatric Trauma Death Review Data Unit received coronial notification of childhood drowning deaths. Age-specific annual drowning rates per 100,000 population were calculated.

SUBJECTS

Children aged 0-14 years who died of drowning.

RESULTS

132 children drowned (96[73%] aged 0-4 years). There was was an overall decrease in incidence of drowning, from 2.0 to 1.5 per 100,000 population, and a decline in domestic pool drownings (from a peak of 15 in 1992 to five in 1995), and in drownings in waterways (from nine to six over the six-year period). However, drownings in baths and dams did not decrease. In general, boys were at higher risk than girls.

CONCLUSIONS

Analysis of the drowning incidents indicates that, despite the decreases documented, we should not be complacent, and preventive programs are still warranted. All pools and dams should have well maintained fences between the body of water and the house. All infants aged under three and all epileptic children should be supervised in the bath by an adult. Children should be taught to swim, warned of the dangers of rivers and surf, and adequately supervised.

Changing patterns of diagnosis and treatment of infantile hypertrophic pyloric stenosis: a clinical audit of 303 patients

This review of 303 patients with infantile hypertrophic pyloric stenosis (IHPS) concentrates on the influence of clinical audit on diagnosis, complications, and factors contributing to hospital stay. Although the audit has enabled improvement in care by pediatric surgeons, there has been less change in areas controlled by other specialities. During a 12-year period, the number of patients diagnosed solely by clinical examination decreased from 74% to 28%, and the use of diagnostic tests increased (ultrasonography from 16% to 65% and barium meal from 12% to 28%). This trend continued throughout the series despite a review after 8.5 years, which recommended fewer tests. Although there may be some benefit from earlier confirmation of IHPS (the percentage of patients with a serum chloride value of less than 85 mmol/L decreased from 26% to 15%), the need for diagnostic tests could be reduced by expectant management. Better improvement occurred with surgical complications; the incidence of mucosal perforation decreased from 7 of 151 (4.6%) in the first 6 years to 0 of 152 in the last 6 years, and wound dehiscence was reduced from 3 to 0. The wound infection rate decreased from 9% to 4%, but had fluctuations. The average length of stay was reduced from 3.7 to 3.2 days. Further reductions in hospital stay will depend on earlier operation for patients with normal electrolyte values at the time of admission (61%) and a preparedness to confidently discharge patients even if there is vomiting. From the data available, early operation on the day of admission and discharge the next day would be a reasonable strategy for the majority of patients whose admission electrolyte values are normal. Complications such as mucosal perforation and wound dehiscence should be rare. This is not to suggest that IHPS is a condition of minor consequence; the surgeon must be skilled and care meticulous. If electrolytes are disturbed at the time of operation or if unrecognized mucosal perforation occurs, what should be an uneventful illness can result in disaster.

School bus related deaths and injuries in New South Wales

OBJECTIVE

To report the circumstances of paediatric bus related deaths and injuries in New South Wales (NSW) to identify preventable factors.

DESIGN

Retrospective survey using two surveillance systems-the NSW Paediatric Death Review Database and the Childsafe Injury Surveillance System.

PATIENTS

Children (0-14 years of age) who died or were injured as a result of a school bus related incident.

RESULTS

Twenty-two deaths and 58 injuries were recorded. Three of the children who died were passengers (two deaths were due to errant behaviour), two were alighting from the bus (bus door entrapment) and 17 (77%) were pedestrians crossing the road before or as the bus departed. The major causes of death were head injury and blood loss. Seventeen of the injured children were pedestrians and most (82%) of these sustained serious injury requiring admission to hospital.

CONCLUSIONS

The greatest risk to schoolchildren from bus related injuries was as pedestrians after alighting from a bus, especially when moving behind the bus. Preventable factors include slowing of traffic (40 kph) near stationary school buses, and parents waiting on the side of the road where the child alights from the bus. Continuing road safety education remains important for schoolchildren and parents as well as for drivers.

Null mutation of endothelin receptor type B gene in spotting lethal rats causes aganglionic megacolon and white coat color

Mutations in the gene encoding the endothelin receptor type B (EDNRB) produce congenital aganglionic megacolon and pigment abnormalities in mice and humans. Here we report a naturally occurring null mutation of the EDNRB gene in spotting lethal (sl) rats, which exhibit aganglionic megacolon associated with white coat color. We found a 301-bp deletion spanning the exon 1-intron 1 junction of the EDNRB gene in sl rats. A restriction fragment length polymorphism caused by this deletion perfectly cosegregates with the sl phenotype. The deletion leads to production of an aberrantly spliced EDNRB mRNA that lacks the coding sequence for the first and second putative transmembrane domains of the G-protein-coupled receptor. Radioligand binding assays revealed undetectable levels of functional EDNRB in tissues from homozygous sl/sl rats. We conclude that EDNRB plays an essential role in the normal development of two neural crest-derived cell lineages, epidermal melanocytes and enteric neurons, in three mammalian species--humans, mice, and rats. The EDNRB-deficient rat may also prove valuable in defining the postnatal physiologic role of this receptor.

Interstitial deletion of the endothelin-B receptor gene in the spotting lethal (sl) rat

The autosomal recessive spotting lethal (sl) rat phenotype is characterized by absence of intramural ganglion cells in the entire colon and distal small bowel, thus resembling the human Hirschsprung (HSCR) disease. A strategy for identifying the gene responsible for this rat defect was initiated by backcrossing DA x sl rats. After excluding linkage with two candidate genes, RET and Endothelin-3 (EDN3), a highly significant lod score (Z = 47.05 at theta = 0) was found between the Endothelin-B Receptor (EDNRB) gene and the sl phenotype. The exon-intron structure of this rat gene was reconstructed and each exon of the sl rat was screened for possible mutations. A 301 bp interstitial deletion, encompassing the distal half of the first coding exon (exon 2) and the proximal part of the adjacent intron, was demonstrated. This deletion results in two transcriptional products, 270 and 238 bp shorter than wild type cDNA. The discovery of the molecular defect underlying the sl rat phenotype should contribute to the understanding of the genetic heterogeneity of HSCR in man.

Mutation analysis of the RET receptor tyrosine kinase in Hirschsprung disease

Hirschsprung disease (HSCR), or congenital aganglionic megacolon, is the most common cause of congenital bowel obstruction with an incidence of 1 in 5000 live births. Recently, linkage of an incompletely penetrant, dominant form of HSCR was reported, followed by identification of mutations in the RET receptor tyrosine kinase. To determine the frequency of RET mutations in HSCR and correlate genotype with phenotype, we have screened for mutations among 80 HSCR probands representing a wide range of phenotypes and family structures. Polymerase chain reaction (PCR) and single-strand conformation polymorphism (SSCP) analysis of RET's 20 exons for mutations among probands revealed eight putative mutations (10%). Sequence changes, which included missense, frameshift and complex mutations, were detected in both familial and isolated cases, among patients with both long- and short-segment HSCR and in three kindreds with other phenotypes (maternal deafness, talipes and malrotation of the gut, respectively). Two mutations (C609Y and C620R) we identified have previously been associated with multiple endocrine neoplasia type 2A (MEN2A), medullary thyroid carcinoma (MTC) and, on rare occasions, HSCR. Thus, while HSCR family members may be at risk for developing neuroendocrine tumors, it follows that identical mutations in RET may be able to participate in the pathogenesis of distinct phenotypes. Our data suggest that: (i) the overall frequency of RET mutations in HSCR patients is low and therefore, other genetic and/or environmental determinants contribute to the majority of HSCR susceptibility, and (ii) at present, there is no obvious relationship between RET genotype and HSCR phenotype.

Postnatal diagnosis and outcome of urinary tract abnormalities detected by antenatal ultrasound

OBJECTIVES

To determine the incidence of urinary tract abnormalities detected by antenatal ultrasound; the value of fetal renal measurements in predicting significant uropathy; and the nature and clinical outcome of fetal uropathy.

DESIGN AND SETTING

A retrospective analysis of babies with urinary tract abnormalities detected before birth who were born at or referred to a teaching hospital.

PATIENTS

One hundred and twenty-five babies born between June 1989 and November 1992. Sixty-nine babies were born at Westmead hospital and 56 were born elsewhere and referred to Westmead Hospital for investigation.

RESULTS

The incidence of uropathy detected before birth among babies born at the teaching hospital was 5.1 per 1000 births. In 60% of these babies, significant abnormalities were confirmed after birth (3.1 per 1000 births). We found a significance of 71% and a specificity of 89% for fetal measurements in predicting significant uropathy. Among all 125 babies the most common abnormalities were pelviureteric junction (PUJ) anomalies (34%), minimal hydronephrosis (26%), ureteric reflux (18%) and multicystic kidney (7%). Pyeloplasty has been performed in 23 (46%) of the 52 kidneys with PUJ anomalies. Renal parenchymal abnormality was detected in four of 22 kidneys with ureteric reflux (18%). Of these four, all were exposed to Grade IV or V ureteric reflux but none had been infected.

CONCLUSIONS

Antenatal ultrasound is a sensitive, though nonspecific, tool for the non-invasive identification of congenital abnormalities of the urinary tract, which are common and frequently asymptomatic after birth. Although ureteric reflux may not be predicted from renal measurements, the degree of fetal hydronephrosis indicates the likelihood of obstructive abnormality and, thus, the extent of postnatal investigation required.

A medium term follow-up study of patients with hypertrophic pyloric stenosis

A structured questionnaire was sent to the parents of 120 children from a cohort 192, who had undergone a pyloromyotomy for pyloric stenosis at Westmead Hospital during the years 1984-91. Information was gained from 85 children in 82 families regarding gastrointestinal complaints and family history of pyloric stenosis. There were few gastrointestinal problems, no reports of recurrent abdominal pain, but two reports of clinically significant vomiting (2.3%) and one of infantile colic. Of the 85 individuals studied, 21 (24.7%) had a positive family history of pyloric stenosis, a higher frequency than previously reported.

Infantile hypertrophic pyloric stenosis: a clinical review from a general hospital

A review of 212 cases of infantile hypertrophic pyloric stenosis (IHPS) in a general hospital during an 8.5 year period documents clinical features and suggests refinement of treatment. Features such as sex, age at onset and presentation were similar to other studies. There was a preponderance of infants born in the summer. Premature infants represented 10% of the series, and the most premature (< 33 weeks gestation) presented later after birth (40 vs 25 days). Diagnosis was clinical in 65% of cases, but 4% presented before physical examination and diagnostic tests were positive. At the time of admission only 15% had significant abnormalities of serum electrolytes (chloride < 85 mmol/L). The periumbilical incision resulted in a hidden scar. Duodenal perforation (3.3%) and wound dehiscence (1.4%) are related to technical factors and can be avoided. The timing of commencement of postoperative feeds did not influence the rate of vomiting. The average length of stay was 3.5 days. These results are discussed with suggestions about how to minimize diagnostic tests and length of hospital stay.

A gene for Hirschsprung disease (megacolon) in the pericentromeric region of human chromosome 10

Hirschsprung disease (HSCR) is characterized by a congenital absence of enteric ganglia along a variable length of the intestine. Although long considered to be a multifactorial disease, we have identified linkage in a subset of five HSCR families to the pericentromeric region of chromosome 10, thereby providing monogenic inheritance in some families. A maximum two-point lod score of 3.37 (theta = 0.045) was observed between HSCR and D10S176, under an incompletely penetrant dominant model. Multipoint, affecteds-only and non-parametric analyses supported this finding and localize this gene to a region of approximately 7 centiMorgans, in close proximity to the locus for multiple endocrine neoplasia type 2 (MEN2). The co-occurrence of these two entities in some families might be attributable to shared pathogenetic origins.

Splenic injury in children: a 10 year experience

The aim of this report was to review retrospectively the management of splenic trauma at a major Australian tertiary referral centre (Westmead Hospital) over a 10 year period. Forty-nine patients (0-15 years of age) with documented blunt splenic trauma were identified. The causes of splenic injury were road trauma (73%) and falls (27%). There were 22 minor injuries (Injury severity score [ISS] < 16) and 27 severe injuries (ISS > or = 16). All nine deaths were related to road trauma (mean ISS = 59). The investigation most commonly used was CT scanning (47%). Peritoneal lavage was performed in six patients (12%). Management involved non-operative care in 29 patients (57%), exploratory laparotomy alone in 5 (10%), splenic salvage in 2 (4%) and splenectomy in 13 (26%). This experience supports the view that non-operative management of splenic injury in haemodynamically stable children is safe and is the preferred treatment. Experienced assessment and meticulous observation is necessary. Laparotomy is indicated if there is continuing haemodynamic instability despite resuscitation. Operative management is aimed at splenic salvage with splenectomy being reserved for uncontrolled haemorrhage.

Oesophageal perforation caused by a coin

An unusual consequence of an initially asymptomatic coin ingestion is described to alert paediatricians that coins are not always innocuous. The case illustrates the need to investigate subtle but persistent symptoms, and also describes the surgical approach to coins that erode through the oesophageal wall.

Association of Hirschsprung's disease and Müllerian inhibiting substance deficiency

An infant who presented with Hirschsprung's disease was found to also have the clinical features of persistent Müllerian duct syndrome and on testing to have Müllerian inhibiting substance deficiency. This association has not been previously reported. While this may be a coincidence, recent reports indicate intersex conditions can be associated with Hirschsprung's disease.

Aganglionosis in rodents

The etiology of aganglionosis of the bowel remains controversial. Initial embryological studies in chicks, mice, and humans suggested the defect was in the migratory capacity of the vagal neural crest cells. This traditional theory has recently been challenged by the demonstration of a defect in the local microenvironment and the suggestion that neural crest cells migrate normally until they reach the terminal defective segment of bowel which then excludes them. To contribute to this debate we studied three rodent animal models using histological, "in vivo" (kidney capsule), and "in vitro" (tissue culture) techniques. The results suggest that there is no discernible difference between mutant and normal embryos in the early migration from the vagal neural crest to the stomach. Migration through the small bowel is normal in mutant mice, but is slowed in the rat. In both strains of mice the migration of enteric precursors into the mutant colon is slowed over an extended period of time, such that a difference between normal and mutants is evidenced well before the final aganglionic region is reached. Aganglionosis is the result either of a defect in vagal neural crest migration or in the microenvironment over an extended area of the bowel and not just in the terminal aganglionic colon. There are changes in the appearance of mutant enteric neurons in tissue culture and some alterations in the gut mesenchyme; it remains to be determined which is the primary event.

Child drownings: a changing pattern

Paediatric drownings in New South Wales during the years 1987-1990 are reviewed to document the current pattern. Over these three years we have registered 250 paediatric deaths by physical injury. Sixty-one (24%) of these deaths were by drowning. Twenty-nine of the 61 drownings (47%) occurred in domestic pools; 25 of these were in unfenced or inadequately fenced pools. Of the remaining four cases, one was associated with a chair being used to gain access and the other three remain unexplained. Thirty-three of the 61 drownings occurred in country areas; of these 10 were in pools, eight in rivers or creeks, six in boating accidents, four in the surf and three in dams. A changing trend identified by this study is the increasing percentage of drownings (44%) occurring in nominally "fenced" pools in which the fencing was not functioning because the gate was open or the fencing was in disrepair. Legislation must be supported by public education and council inspection if the full benefit of isolation fencing is to be realised. With respect to all drownings there is a continuing need for education about the dangers that bodies of water, even in the bath or a bucket, pose to young children, and the need for parents to strive for optimal supervision.

Skateboard injuries

The recent increase in skateboard injuries is causing concern. Over a 30-month period there were 80 admissions (69 children) to Westmead Hospital because of skateboard injuries. Among children most injuries were minor, involving fractures to the upper limbs (47) or minor head injuries (8). The only serious injuries were a ruptured urethra and a closed head injury. Over the same time period skateboard riding caused five deaths in New South Wales. These all involved head injuries and in four instances collisions with cars. The data strongly support other studies that show skateboard riding is particularly dangerous near traffic and should be proscribed. However, in parkland and around the home the skateboard is an enjoyable toy with an acceptable risk of minor injury. Helmets should be worn and would have prevented all the head injury admissions in this series. Children under 10 have a higher risk of fractures and head injuries due to insufficient motor development to control the boards and the resultant falls. Skateboard injuries are an example of injuries caused by a "fad epidemic". To cope with these types of periodic events up-to-date data collection is needed, followed rapidly by an intervention programme so that serious injuries can be kept to a minimum.