Postoperative ambulatory level after hip fracture in the elderly predicts survival rate

The purpose of this study was to evaluate whether the ambulatory level premorbid or at discharge reflected the survival rate better. Ambulatory level was retrospectively evaluated as a postoperative indicator of survival rate following operative treatment in 301 consecutive patients over 65 years old. All of the patients were followed up for a mean of 62 months. The postoperative ambulatory level at discharge reliably reflected the survival rate in the elderly after hip fracture, better than the premorbid ambulatory level. It is confirmed that the planning of the operation and rehabilitation to maintain the premorbid ambulatory level after hip fracture might be critical.

Observation of untreated patients with neuroblastoma detected by mass screening: a "wait and see" pilot study

BACKGROUND

Recent studies have indicated that mass screening for neuroblastoma detects tumors that otherwise would have regressed spontaneously without recognition. Therefore, we started an observation program for these patients to determine how frequently spontaneous regression occurs.

PROCEDURE

Eighteen patients were detected by mass screening between June 1994 and December 1996. Eight of these cases matched the following criteria and entered the observation program: Stage I or II, less than 5 cm in diameter; no involvement of large vessels or organs; not difficult to resect; informed consent. If there were an increase in tumor size, an elevation of tumor markers, or evidence of metastasis, the tumor would be immediately resected.

RESULTS

Five of the eight cases showed spontaneous regression. Although the remaining three tumors were resected 6-10 months after diagnosis, all patients survived without evidence of recurrence.

CONCLUSIONS

At least 60% of neuroblastoma cases who entered our observation program regressed spontaneously.

Clinical characteristics of congenital esophageal stenosis distal to associated esophageal atresia

BACKGROUND

Congenital esophageal stenosis (CES) has been reported to be a rare association in patients with esophageal atresia or tracheoesophageal fistula, or both (EA-TEF). This study investigates the clinical characteristics of this association with special reference to its treatment.

METHODS

A retrospective review of medical and radiographic records of 81 patients who underwent primary repair of EA-TEF was performed. An association of CES was diagnosed when they showed histologic evidence or persistent radiographic images of esophageal narrowing since the neonatal period.

RESULTS

Eleven of 81 EA-TEF patients (14%) were identified with CES. Their symptoms were difficulty in swallowing solid food, food impaction, emesis, stridor, repeated respiratory infection, and failure to thrive. Two patients had a recurrence of TEF. Three patients were diagnosed with CES in the neonatal period-2 at the time of primary repair of EA-TEF and 1 on the initial postoperative esophagram. The remaining 8 patients were diagnosed between the ages of 2 months and 3 years. Although esophageal dilatation was attempted in 9 patients, its effectiveness was temporary in all except 2 patients and esophageal laceration occurred in 4 patients. Surgical repair including myotomy and resection of the narrow segment was performed in 7 patients, in 6 of whom Nissen/Collis-Nissen fundoplication was added. A histologic examination was performed in 5 patients, revealing that their CES was due to fibro-muscular hypertrophy (2) or tracheobronchial remnants (3). The long-term outcome was satisfactory in all patients except one who showed wrap herniation.

CONCLUSIONS

The association between CES and EA-TEF is not rare. Esophageal dilatation was not universally effective and carried with it a considerable incidence of esophageal leakage. An antireflux operation concomitant with repair of CES may be useful to prevent postoperative gastroesophageal reflux in patients with a narrowing close to the esophagogastric junction.

Perioperative nutrition and metabolism in pediatric patients

A developing child, with a high metabolic rate and low body stores of nutrients, is susceptible to metabolic disturbances due to surgical stress. For perioperative nutritional care of infants, the distinct physiologic features of their body fluids must be carefully considered. The postoperative metabolic response is the same as that in adults, but in children this response is more rapid. Based on the urinary excretion of 3-methylhistidine in infants, the postoperative degradation of muscle protein is thought to be twice the preoperative level. This transient increase during the early postoperative period was not suppressed by increased amino acid intake, and energy intake was sufficient. To prevent postoperative metabolic complications, the energy intake of glucose or fat should correspond to the patient's requirements, and excess carbohydrate should be avoided. The quantity and quality of the amino acid formula used must be carefully evaluated.

Motor function of the esophagus and the lower esophageal sphincter in children who undergo laparoscopic nissen fundoplication

BACKGROUND/PURPOSE

To define the clinical role of laparoscopic Nissen fundoplication (LNF) in children with gastroesophageal reflux (GER), an appropriate understanding of its functional effects is required. The aim of this study was to investigate the motor function of the esophageal body and the lower esophageal sphincter (LES) with special reference to the effects of caloric nutrients in children undergoing LNF.

METHODS

Studies were performed in 12 children with GER (age, 6 months to 13 years) before and a month after LNF. Continuous manometric examination was performed with an infusion system using a sleeve sensor for an hour each before and after the administration of apple juice (AAJ; 10 mL/kg).

RESULTS

AAJ increased postoperative basal LES pressure from 15 +/- 7 to 20 +/- 6 mm Hg, whereas it decreased the preoperative values from 13 +/- 5 to 10 +/- 4 mm Hg (P < .05). Significant residual pressure was noted at the nadir of swallow-induced LES relaxation after LNF, which was increased by AAJ from 7 +/- 3 to 11 +/- 4 mm Hg. A child with a high nadir LES pressure showed postoperative dysphagia. Significant changes in the patterns of esophageal contractions were not noted after LNF.

CONCLUSIONS

Characteristics of the effect of LNF on the LES were a postprandial increase of basal LES pressure and significant residual LES pressure at the nadir of LES relaxation. The motor function of the esophageal body was not affected by LNF.

Measurement of serum hyaluronic acid as a sensitive marker of liver fibrosis in biliary atresia

PURPOSE

The aim of this study was to clarify whether serum hyaluronic acid level (SHA) can reflect the degree of liver fibrosis in biliary atresia (BA).

METHODS

SHA was measured in 44 postoperative BA patients at 7 months to 22 years of age, with sandwich enzyme method (Hy-A 100 kit). SHA was compared with T.Bil (group 1, T Bil < 2; group 2, 2 < or = T Bil < 5; group 3, T Bil > or = 5 mg/dL), fibrosis score (0-6, the number of abnormal values among Alb, PT, ChE, T Chol, Fischer's ratio, prealbumin), and histologic grading (0-IV).

RESULTS

SHA was 499.8 +/- 332.5 in group 3, significantly higher than in the control, group 1, or group 2. As fibrosis score rose, SHA became higher, and SHA in Score 6 (430.1 +/- 366.1 ng/mL) and score-5 (172.9 +/- 141.8 ng/mL) was significantly higher than in the control and other scores, respectively. As the histologic grade rose, SHA became higher, and SHA in grade IV (444.8 +/- 323.5 ng/mL) and grade III (166.0 +/- 70.3 ng/mL) was significantly higher than in the control or other Grades. Serial change of SHA since before HPE was parallel to the clinical course in 8 patients.

CONCLUSION

SHA may be a useful serum marker reflecting the degree of liver fibrosis in BA.

Cl(-) secretion in colonic epithelial cells induced by the vibrio parahaemolyticus hemolytic toxin related to thermostable direct hemolysin

A hemolytic toxin related to thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH), produced by Kanagawa-phenomenon-negative Vibrio parahaemolyticus is suspected of playing an important, but yet-to-be-elucidated role in diarrhea caused by this organism. In cultured human colonic epithelial cells, TRH increases Cl(-) secretion, followed by elevation of intracellular calcium.

Total parenteral nutrition-associated intrahepatic cholestasis in infants: 25 years' experience

BACKGROUND/PURPOSE

There are few long-term chronological reviews examining the incidence of total parenteral nutrition (TPN)-associated intrahepatic cholestasis (TPNAC) in infants. The authors therefore reviewed TPNAC in their 25-year series, and also looked at the current problems associated with TPN in infants.

METHODS

Two hundred seventy-three surgical neonates who received TPN for more than 2 weeks were divided into 3 groups chronologically: group A (1971 through 1982, n = 77), group B (1983 through 1987, n = 72), and group C (1992 through 1996, n = 124). TPNAC was defined as serum direct bilirubin (DB) level greater than 2.0 mg/dL during the neonatal period.

RESULTS

The incidence of TPNAC in groups A, B and C was 57%, 31%, and 25% (P< .01), respectively, and the mortality rate from TPN-associated complications was 13%, 3%, and 3% (P< .05), respectively. Over the last 5 years, severe TPNAC developed in 20 patients (16%). Four of 20 died of TPN-associated sepsis with hepatic failure; 2 had hypoganglionosis with intractable stagnant enteritis and subsequent sepsis, and 2 had fatal respiratory or cardiac disease.

CONCLUSIONS

The incidence of TPNAC in surgical neonates and TPN-associated mortality rates have decreased significantly. The mortality rate, however, still remains at 3%. Two of 4 fatal cases had hypoganglionosis, which were totally dependent on TPN. In patients who require long-term TPN, TPN still has unsolved problems, and small bowel transplantation may be indicated.

Meconium peritonitis in utero

To clarify the relationship between clinical features in utero and postnatal prognosis, 20 fetuses who underwent ultrasonic (US) evaluation for meconium peritonitis (MP) over a 17-year period were reviewed. According to final US findings in utero, patients were classified into three types. Type I (massive meconium ascites) was noted is 5 cases, type II (giant pseudocyst) in 4, and the other 11 were classified as type III (calcification and/or small pseudocyst). Abdominal calcifications were identified in only 5 cases (2 type I, 1 type II, 2 type III). Seven fetuses who had associated polyhydramnios (1 Type I, 1 Type II, 2 Type III) and fetal hydrops (3 Type II) were delivered before 36 weeks' gestation. Cardiopulmonary resuscitation at birth was required in 9 cases (5 type I, 4 type II) who underwent abdominal drainage before delivery and/or immediately after birth. Although dilatation of the intestine was identified in 10 fetuses (2 type II, 8 Type III), 18 had intestinal atresia and 2 had fecal obstruction of the distal ileum. Four infants (2 type I, 1 type II, 1 type III) died of respiratory failure and postoperative complications. These results indicated that careful fetal US may be useful for perinatal management of MP.

Congenital diaphragmatic hernia in identical twins

The authors present a pair of identical twins with congenital diaphragmatic hernia (CDH) diagnosed prenatally, who underwent successful surgical repair. They were diagnosed as having CDH at 32 weeks' gestation and showed respiratory distress soon after cesarean section at 33 weeks' gestation. Both survived after scheduled perinatal management followed by surgery, for which the prenatal diagnosis of CDH was valuable.

Functional ileus in neonates: Hirschsprung's disease-allied disorders versus meconium-related ileus

Sixty-eight neonates with functional ileus were reviewed. Twelve required laparotomy; in seven, histological studies revealed decreased ganglia and ganglion cells of the myenteric plexus (MP) (Group A), and in five, MP was normal (Group B). In the remaining 56 cases, obstructive symptoms were relieved following conservative therapy (Group C). All Group A cases except one had normal birth weight, while Group B and C cases showed significantly lower birth weights. A marked caliber change of the small intestine and/or small-caliber distal intestine with meconium stagnation in the proximal intestine was commonly demonstrated at operation in Group A and B, or on contrast enema in Group C. Four Group A cases died of enteritis, and three survivors suffered from prolonged obstructive symptoms. The grade of histological abnormality of MP correlated with the clinical outcome. In Group B, three died of sepsis shortly after surgery, but two survivors have been free from symptoms. Group A can be categorized as Hirschsprung's disease-allied disorders (HAD). Group B and C can be categorized as meconium-related ileus (MRI). The similarity of the macroscopic findings of HAD and MRI, and the occurrence of MRI exclusively in low birth weight neonates, strongly suggest that functional immaturity of MP plays a role in the etiology of MRI.

Tracheal agenesis in a child who survived for 6 years

The authors report on a child with tracheal agenesis who survived for 6 years and 10 months. A female infant was born with respiratory distress and an absence of audible cry. With mask ventilation, gastrostomy and division of the esophagus was performed just after birth. She was well ventilated with an endotracheal tube inserted through the cervical esophagostomy after thoracic esophageal banding. An accidental extubation caused her anoxic encephalopathy at 9 months of age. She had been alive without artificial ventilatory support until she died of acute esophageal bleeding.

A clinical and molecular study of a patient with Simpson-Golabi-Behmel syndrome

Simpson-Golabi-Behmel syndrome (SGBS) is one of the overgrowth syndromes. Microdeletions of the glypican-3 (GPC3) gene were described by Pilia et al. (1996). Glypican-3 encodes a putative extracellular proteoglycan which is expressed in embryonic mesodermal tissues and plays an important role in embryonal growth. We report a Japanese patient with SGBS who had a single base deletion in the exon 7 of the GPC3 gene. This is the first report of a single base deletion of the GPC3 gene.

Use of a Palmaz stent for tracheomalacia: case report of an infant with esophageal atresia

A male infant with congenital cardiac anomalies and esophageal atresia with tracheoesophageal fistula (EA-TEF) showed intractable respiratory symptoms after delayed primary repair of EA-TEF. Computed tomography demonstrated that the trachea was compressed by the enlarged aorta. Artificial ventilation was necessary even after aortopexy performed at 2 months of age. At 140 days of age, an expandable metallic stent (Palmaz stent) was inserted through a rigid bronchoscope into the trachea underfluoroscopic control. His respiratory status improved dramatically, and he was extubated in 18 hours. Although the follow-up period has been 9 months, the short-term result is satisfactory. The expandable metallic stent placement should be considered in patients with EA-TEF who show intractable respiratory symptoms caused by tracheomalacia.

Panipenem, a carbapenem antibiotic, enhances the glucuronidation of intravenously administered valproic acid in rats

Previously, a significant decrease in the trough plasma-concentration of valproic acid (VPA) owing to the concomitant administration of panipenem (PAPM)/betamipron, a carbapenem antibiotic, in epileptic patients was reported. To determine the site and mechanism of the drug interaction between VPA and PAPM, we performed in vivo and in vitro experiments using rats. A 30 mg/kg bolus dose of VPA was given i.v. to normal Sprague-Dawley rats, nephrectomized rats, and hepatectomized rats, with and without prior treatment of PAPM. PAPM treatment resulted in a significant reduction of biological half-life and a significant increase of total body clearance in normal rats. The effects of PAPM on the disposition kinetics of VPA were also observed in nephrectomized rats, whereas hepatectomy abolished the interaction completely. Thus, the site of interaction was identified as the liver. At steady state, PAPM treatment significantly increased total body clearance, the biliary excretion rate of VPA glucuronide, and the apparent metabolic clearance of VPA by glucuronidation, but did not affect the biliary excretion clearance of VPA glucuronide. Initial uptake velocity of VPA into rat hepatocytes proportionally increased as a function of VPA concentration added and was not affected by PAPM. The plasma-unbound fraction of VPA in vitro was not altered by PAPM. These data demonstrate that PAPM does not affect the uptake of VPA into the liver, the plasma-unbound fraction, and the excretion process of VPA glucuronide. Consequently, PAPM appears to enhance the rate of metabolism of VPA to VPA glucuronide in the liver.

Treatment with active vitamin D metabolites and concurrent treatments in the prevention of hip fractures: a retrospective study

The purpose of this study was to determine the effect of treatment with active vitamin D metabolites and other concurrent medication on the prevention of hip fractures in elderly women. We inspected the medical records of the entire female population over 65 years of age on Sado Island, and followed a total of 11,377 women for a 3-year period. Of these, 1208 osteoporotic patients were treated with either 1,25-(OH)2D3 or 1 alpha-(OH)D3. The 765 patients who received the minimum effective dosage for more than 6 months made up the 'treatment group'. Nearly half these patients were also treated with either calcitonin or calcium. The 443 patients who received treatment with active vitamin D metabolites, but at a dosage or for a duration that did not meet the criteria for the treatment group, were deemed the 'ineffective group'. The remaining 10,169 women were the 'non-treatment group'. Fractures in the non-treatment group occurred at a rate of 39.8 fractures/10,000 person-years. The rate in the treatment group was 10.8, which was significantly lower (p = 0.039). Interestingly, the fracture rate after ceasing treatment was 52.1, which was significantly higher (p = 0.002) than the rate in patients receiving treatment. No statistical differences in the fracture rate were found between the ineffective, non-treatment and post-treatment groups. A reduction in the fracture rate was observed only in the treatment subgroup that did not also receive calcitonin (p = 0.042), and not in the subgroup that also received calcitonin therapy (p = 0.333). However, there was no statistical difference in the hip fracture rates between these two subgroups (p = 0.157) and the actual number of fractures was minimal (0 vs 2). Therefore, in this study, the advantage of treatment with active vitamin D alone over combined treatment with calcitonin seems to be marginal.

IN CONCLUSION

(1) treatment with active vitamin D metabolites and with combined therapy may be marginally effective in preventing hip fractures, and (2) stopping the treatment clearly increases the risk of hip fractures.

Clinical significance of the lung/thorax transverse-area ratio in fetuses with cystic lung disease

We examined the clinical significance of the lung-thorax transverse-area ratio (L/T) in fetuses with cystic lung disease (CLD). The transverse section of the thorax was analyzed at the level of the 4-chamber view of the heart. L/T was calculated as the bilateral normal lung area divided by the thoracic area. Within a 9-year period, ultrasonography was performed in 15 fetuses with CLD, 13 of which were histologically diagnosed: congenital cystic adenomatoid malformation of the lung (CAM; n = 8), pulmonary sequestration (n = 4), and bronchial atresia (n = 1). Although the initial L/T measurement (29.6 +/- 4.2 weeks) showed significantly lower values than in the controls, the final measurement (36.4 +/- 1. 6 weeks) indicated that the L/T in CLD excluding CAM was significantly higher than that in CAM. Six patients with a final L/T of less than 0.21 required mechanical ventilation immediately after birth. Two of these patients died, and the autopsy findings indicated pulmonary hypoplasia. In these cases, a significant correlation was observed between the maximal value of L/T and preductal alveolar-arterial oxygen difference (A-aDO(2)), although the final L/T was not correlated to A-aDO(2). These results indicate that serial measurements of L/T may be useful in the diagnosis of CLD and may help to predict postnatal respiratory conditions.

Pyloric motor abnormality in patients with infantile hypertrophic pyloric stenosis

There are no published data of manometric studies of pyloric motor function in patients with infantile hypertropic pyloric stenosis (IHPS). The present study attempted to examine the characteristics of motor abnormality of the pylorus in five children with IHPS. Using a transducer-built-in manometric catheter cannulated through the pylorus under fluoroscopy, the pressure in the pyloric canal was recorded continuously over 3 h during fasting. Clusters of high-amplitude spastic contractions of over 300 mmHg were recorded at intervals. The frequency was 1-3/min (mean 1.7 cpm) and the duration was 7-15 s. These periodic spastic contractions were suppressed temporarily for 20-30 min after intravenous injection of 0.01 mg/kg atropine. After pyloromyotomy, these spastic contractions decreased remarkably in amplitude, but there were no changes in frequency. It is concluded that the underlying motor abnormality observed in hypertrophied pyloric muscle is clusters of high-amplitude contractions, although more precise measurements of basal pyloric pressure are needed to explore the pathophysiology of IHPS in detail. The effect of pyloromyotomy may be related to the decrease in high-amplitude contractions.

Transcatheter arterial chemoembolization in the treatment of hepatoblastoma

BACKGROUND

The prognosis of hepatoblastoma is poor unless the tumor is completely resected. Various types of chemotherapy have been developed to increase its resectability. Recently, transcatheter arterial chemoembolization (TACE) has been developed for the treatment of unresectable adult hepatoma with favorable results. The authors applied this procedure to hepatoblastoma in infants and children.

METHODS

TACE was performed in eight hepatoblastoma cases. After an intraarterial catheter was inserted into the main feeding artery of the tumor, injection of adriamycin or THP-adriamycin (20 to 30 mg/m2) dispersed in lipiodol and cisplatin (40 to 60 mg/m2) followed by embolization using Gelfoam pieces was performed. Effects of TACE were evaluated according to shrinkage of tumor mass on imaging examinations, alpha-fetoprotein (AFP) levels, and pathological findings of the surgical specimens 4 weeks after TACE.

RESULTS

A marked reduction in tumor size associated with a decrease in AFP level occurred 1 month after the treatment. Tumor shrinkage ranged from 0.9% to 45.0% with a mean value of 25.8%. AFP levels decreased by 0.2% to 11.9% with a mean level of 4.6% from initial levels. In addition, there was no marked chemotherapeutic agent-induced toxicity noted during the observation period. Resection of the tumors was performed safely after TACE in all cases. Pathological examination showed massive necrosis in the surgical specimens, and the mean percentage of necrotic area within the tumor was 71.1%. Two patients died of extensive lung metastasis 2 months and 3 years after the operation, respectively. The remaining six were doing well and free of disease at a mean follow-up period of 50 months.

CONCLUSION

TACE is an effective, safe, and useful method for the initial treatment of hepatoblastoma.

Mechanisms underlying the antireflux effect of Nissen fundoplication in children

BACKGROUND/PURPOSE

It is reported that the main mechanism responsible for gastroesophageal reflux (GER) is transient lower esophageal sphincter (LES) relaxation in children. However, the effect of Nissen fundoplication on transient LES relaxation has not been investigated in children. This study examined the effect of Nissen fundoplication on motor patterns of the LES in children with pathological GER.

METHODS

Esophageal manometry and pH were recorded concurrently for 2 hours after administration of apple juice (10 mL/kg). In seven children documented to have pathological GER by prolonged esophageal pH monitoring (%time pH less than 4.0>5.0), studies were performed preoperatively and 1 to 3 months after surgery.

RESULTS

Nissen fundoplication virtually eliminated reflux in all patients. Percentage of time pH was less than 4.0 reduced from 15+/-9 to 0+/-0. Basal LES pressure did not change significantly (pre, 21+/-10 mm Hg v post, 27+/-9 mm Hg). The number of transient LES relaxation reduced significantly from 13+/-4 to 7+/-7, and the mean nadir LES pressures during swallow-induced LES relaxation and transient LES relaxation increased significantly from 1+/-1 mm Hg to 13+/-5 mm Hg and from 0+/-0 mm Hg to 11+/-7 mm Hg, respectively.

CONCLUSIONS

Our findings suggest the antireflux effects of Nissen fundoplication may be based on changes of LES motor patterns that result in incomplete LES relaxation and reduction of the number of transient LES relaxation.

Prolonged preoperative stabilization using high-frequency oscillatory ventilation does not improve the outcome in neonates with congenital diaphragmatic hernia

Although delayed repair with preoperative stabilization using high-frequency oscillatory ventilation (HFOV) has been advocated in neonates with congenital diaphragmatic hernia (CDH), improved survival has not been reported. We compared survival between neonates undergoing delayed repair after prolonged stabilization for more than 48 h using HFOV and those undergoing immediate repair following short stabilization using HFOV in subjects with high-risk CDH. Patient selection was made by two criteria: fetuses with the lung/thorax transverse area ratio (L/T) below 0.26 and neonates who presented with respiratory distress significant enough to require intubation within 6 h after delivery. Selection of the strategies differed by era and medical center. Stabilization failed in 11 of 18 patients with delayed repair and only 7 patients (38.9%) in this group survived, but 18 of 23 patients (78.3%) in the immediate-repair group survived (P < 0.05). Although lower values of Apgar scores, best postductal PO2 (BPtDPO2), gestational weeks, and L/T and more frequent patch repair were observed in the delayed than in the immediate repair group, significant differences in survival among the subpopulations were also observed in the prenatally diagnosed group, including the group with L/T < 0.15 and the group that required ECMO, the group with the best preductal PO2 (BPrDPO2) >/= 100 torr, and the group with BPtDPO2 < 100 torr. These results indicate that prolonged stabilization for more than 48 h using HFOV does not improve survival in patients with high-risk CDH.

Successful double autografts for patients with relapsed clear cell sarcoma of the kidney

Although the prognosis of clear cell sarcoma of the kidney (CCSK) has improved, when metastases occur the probability of cure is very low. We have treated two pediatric patients with relapsed CCSK, one with multiple bone metastases and another with brain metastases. After one or two courses of re-induction chemotherapy and radiation therapy to the sites of metastasis, they received double high-dose chemotherapy with autologous bone marrow rescue. Conditioning regimens were ifosphamide plus melphalan for the first autograft and busulfan plus thiotepa for the second. Hematological recovery was prompt, and no severe complications were observed. They are doing well without evidence of recurrence at 19 and 49 months after the second autograft, respectively.

Mutational analysis of the endothelin-B receptor gene in Japanese Hirschsprung's disease

BACKGROUND/PURPOSE

Hirschsprung's disease (HD, HSCR) is one of the most common diseases in the field of pediatric surgery. It is well known that the aganglionic bowel is primarily a causative factor of dismotility of distal narrow segment. Recent studies have shown that mutations in endothelin-B receptor (EDNRB), endothelin-3, RET, glial cell line-derived neurotrophic factor (GDNF) genes are responsible for the occurrence of congenital aganglionosis. Here, the authors describe two new mutations of the EDNRB gene in Japanese patients with HD.

RESULTS

One patient had a heterozygous point mutation at the splice donor site of intron 3, leading to premature termination of translation of EDNRB mRNA. Another patient has a heterozygous missense mutation (N1041) in exon 1, but the same mutation was found in two of 50 normal individuals, so the mutation may be a noncausative polymorphism of the EDNRB gene.

CONCLUSION

These results provide further evidence that a spectrum of different mutations within the EDNRB gene are responsible for HD.