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Biomedical subjects

A Yamataka

Publications and source records attributed to A Yamataka.

At least 37 records · Page 2Linked to original sources
PubMed2000

Xanthogranulomatous pyelonephritis in childhood: a rare but important clinical entity.

PURPOSE: Xanthogranulomatous pyelonephritis (XGPN) is extremely rare in children. The authors review their experience of this condition. METHODS: Medical records were investigated to conduct a retrospective study of 4 patients with XGPN (3 boys, 1 girl; age range, 2 months to 7 years) at the authors' institute over the past 14 years. RESULTS: Three of the 4 patients presented with fever of unknown origin and 1 with general fatigue. An abdominal mass was palpable in two cases at initial presentation. Although all patients had pyuria or hematuria, preoperative urine culture was positive in only 2 cases. Preoperative radiologic studies showed that 1 kidney was affected completely in 2 cases and affected partially in 2 cases. Preoperatively, the provisional diagnosis was XGPN in 3 cases, and Wilms' tumor in 1 case. Total nephrectomy was performed in 3 cases and enucleation in 1 case. XGPN was confirmed in all cases by histopathologic studies, but the underlying disease could be identified only in 1 case (cystinuria). All patients did well postoperatively and have had no further health problems over a mean follow-up period of 4.8 years. CONCLUSIONS: XGPN should be considered when there is a history of recurrent or therapy-resistant pyelonephritis. Preoperative radiologic investigation is paramount for diagnosis, and nephrectomy is the treatment of choice, although partial resection or enucleation are adequate for partially affected kidneys.

Child↗
PubMed2000

Tubed latissimus dorsi musculocutaneous flaps for esophageal replacement in puppies: long-term follow-up.

PURPOSE: The aim of this study was to show that a tubed latissimus dorsi musculocutaneous flap (tubed LDMCF) may be useful for treating circumferential esophageal defects. METHODS: A segment of esophagus 3 vertebrae long was excised through a right thoracotomy in each of 6 puppies, and a tubed LDMCF was interposed between the cut ends of esophagus. The puppies were sacrificed after a mean follow-up period of 6.6 years. The tubed LDMCF was examined histologically. Functional integrity was assessed using barium meal and endoscopy before sacrifice. RESULTS: All puppies survived and grew normally on a normal diet, although 4 vomited occasionally. There was smooth passage of barium through the tubed LDMCF without stenosis, although endoscopy showed regrowth of hair. Histologically, no metaplasia, dysplasia, or malignancy was observed in any tubed LDMCF. CONCLUSIONS: The tubed LDMCF is technically safe, obviates the necessity for laparotomy, and long-term follow-up would suggest that it is histologically stable. Thus, it could become an alternative procedure for bridging esophageal defects.

Animals↗
PubMed2000

Idiopathic gastric perforation in neonates and abnormal distribution of intestinal pacemaker cells.

BACKGROUND/PURPOSE: The etiology of idiopathic gastric perforation (IGP) in neonates is unclear. Interstitial cells of Cajal (ICC) express tyrosine kinase receptor C-kit, and act as gastrointestinal pacemaker cells. Stem cell factor (SCF) is a C-kit ligand and plays an important role in immune system homeostasis in the gastrointestinal tract. The authors hypothesized that abnormal distribution of ICC or SCF in the gastric wall (ie, abnormal motility or impaired immunity) could predispose the stomach to IGP. METHODS: Stomachs obtained at postmortem from neonates who died of IGP (n = 7) and other causes (control group; n = 10) were used. Biopsy sections were taken at random from various sites in the stomach, including macroscopically intact areas, and labeled immunohistochemically using antibodies to C-kit(a marker for ICC) and SCF. RESULTS: In all control specimens, ICC were present between the muscle layers and around the myenteric plexuses of the stomach wall. In contrast, ICC were absent in all biopsy sections from 3 of the 7 IGP stomachs. In the remaining 4 IGP stomachs, there were fewer ICC in the muscle layers compared with controls, and ICC were absent around the myenteric plexuses. The distribution of SCF immunoreactivity in IGP and control specimens was similar. CONCLUSION: The findings suggest that a lack of ICC (ie, gastric hypomotility) may be implicated in the etiology of IGP in neonates.

Analysis of Variance↗
PubMed2000

Congenital biliary dilatation.

Congenital biliary dilatation is commonly associated with pancreaticobiliary malunion. Its etiology remains unknown. With the advent of accurate cholangiography, combined abnormalities of the intrahepatic duct, common channel, and pancreatic duct are being identified more frequently in patients with congenital biliary dilatation. Early diagnosis followed by cyst excision is the treatment of choice, even in asymptomatic cases. The treatment of intrahepatic and intrapancreatic ductal diseases such as intrahepatic duct dilatation and stone debris in the intrahepatic duct and common channel are also discussed. The value of intraoperative endoscopy as an adjunct to cyst excision for the prevention of postoperative complications is explained.

Bile Ducts, Intrahepatic↗
PubMed2000

Intraoperative pancreatoscopy for pancreatic duct stone debris distal to the common channel in choledochal cyst.

BACKGROUND/PURPOSE: Pancreatic duct stone debris is a recognised problem in patients with choledochal cyst (CC). The authors present the use of intraoperative pancreatoscopy (IP) in diagnosis and treatment of pancreatic duct stone debris distal to the common channel (distal PDSD). METHODS: Sixty-seven patients with CC treated over the past 12 years were reviewed retrospectively. Distal PDSD was detected in 8 of these 67 cases (11.9%) using cholangiography. IP of the common channel or pancreatic duct at the time of surgery for CC was performed using a pediatric cystoscope in 7 of these 8 cases. RESULTS: All 8 patients had a long common channel. All presented with acute pancreatitis. In 7 of these 8 patients, IP was efficient in detecting and for removing distal PDSD by irrigation. In the remaining case associated with annular pancreas, distal PDSD was identified in the proximal pancreatic duct and was removed directly after incision of the pancreatic duct. Postoperative pancreatitis occurred in only 1 case. All patients are well after a mean follow-up period of 7.3 years. CONCLUSION: Distal PDSD should not be ignored. IP allows direct examination of the pancreatic duct system and facilitates complete removal of distal PDSD, which may be the cause of relapsing pancreatitis or pancreatolithiasis after radical surgery for CC.

Acute Disease↗
PubMed1999

Mast cells and gut nerve development: implications for Hirschsprung's disease and intestinal neuronal dysplasia.

BACKGROUND/PURPOSE: In Hirschsprung's disease (HD), the aganglionic bowel is characterized by the presence of hypertrophic nerve trunks and increased numbers of adrenergic and cholinergic nerve fibers. Intestinal neuronal dysplasia (IND), if associated with HD, occurs proximal to the aganglionic segment in HD, and is characterized by dysplasia of parasympathetic nerves, hyperganglionosis, and giant ganglia. However, the cause of such abnormalities in HD and IND is unclear. Recent reports that mast cells (MC) have been observed in direct contact with nerve fibers generally, suggest that MC are essential for nerve growth and repair. MC synthesize, store, and release nerve growth factor (NGF). NGF supports the development and functional maintenance of sympathetic and cholinergic neurons. The aim of this study was to examine the colonic distribution of MC with respect to nerves in HD and HD associated with IND. METHODS: MC and NGF were examined immunohistochemically in ganglionic, transitional, and aganglionic segments of colon from 20 patients with HD (five patients associated with IND) and 15 age-matched controls. MC were counted in each of five random fields using light microscopy (x100). RESULTS: Interestingly, aganglionic and IND segments had large numbers of MC in all layers compared with ganglionic segments in HD patients and controls (P< .0001). The number of MC in transitional segments was significantly less compared with ganglionic segments in HD patients and controls (P< .01). MC stained positively for NGF, and some were found in contact with abnormal hypertrophic nerve trunks in HD and giant ganglia in IND. CONCLUSIONS: MC may cause hypertrophic nerve trunks and giant ganglia by releasing NGF and also may be an important factor in the excessive development of cholinergic and adrenergic nerve fibers in HD and IND.

Colon↗
PubMed1999

Long-term postsurgical outcome of biliary atresia.

BACKGROUND/PURPOSE: A successful Kasai procedure is effective in creating biliary drainage and radically altering the natural history of infants with biliary atresia (BA). Since its introduction in the 1950s, long-term follow-up would appear to show that only 30% to 50% of patients have a good long-term prognosis despite initially good surgical outcome. The authors reviewed their experience in treating BA from 1968 to 1997 to assess long-term outcome. MATERIALS AND METHODS: The records of 163 patients treated surgically for BA from 1968 to 1997 were reviewed. Forty-eight (29%) were alive at the end of 1997, of whom, 14 had received liver transplants (LT). Surviving patients who had not undergone transplantation were divided into two groups according to clinical condition: group A, normal liver function without cholangitis (CG) and portal hypertension (PH) and group B, liver dysfunction with CG or PH. The study period was divided arbitrarily into three periods, 1968 to 1975 (period I, n = 34); 1976 to 1985 (period II, n = 81); 1986 to 1997 (period III, n = 48). RESULTS: Thirty-four patients were alive without LT at the end of 1997. There were eight patients (mean age, 16.3+/-4.8 years) in group A, and 26 patients (mean age, 14.3+/-7.6 years) in group B. Recently, four group A patients (mean age, 19.3+/-1.9 years) shifted to group B because of sudden deterioration in condition involving severe CG with multiple bile lakes (n = 2), uncontrollable intestinal bleeding (n = 1), and liver atrophy (n = 1). Survival deteriorated with length of follow-up. There were three survivors from 34 patients treated in period I, 16 survivors from 81 patients treated in period II (three had LT), and 29 survivors from 48 patients treated in period III (11 had LT). CONCLUSIONS: Although satisfactory bile drainage can be obtained with portoenterostomy, our data suggest that liver function can deteriorate progressively, with a possible turning point in late adolescence, indicating that as the length of follow-up increases, clinical assessment should be regular and comprehensive. The timing of LT in postoperative BA patients with deteriorating liver function is a vital management issue.

Adolescent↗
PubMed1999

Lack of C-KIT+ mast cells and the development of idiopathic gastric perforation in neonates.

BACKGROUND/PURPOSE: The proto-oncogene c-kit encodes a receptor tyrosine kinase C-KIT. W/Wv mice, which are devoid of C-KIT+ mast cells as a result of mutations in the c-kit gene, develop spontaneous gastric ulceration or perforation after day 7 of life at a high frequency, whereas normal litter mates do not. The authors hypothesized that a lack of C-KIT+ mast cells may be implicated in the development of idiopathic gastric perforation (GP) in neonates. METHODS: Postmortem gastric wall specimens were taken from neonates who died of GP (idiopathic, n = 6; secondary, n = 4), and other causes (controls, n = 6). Specimens were taken at random from various sites in the stomach and labeled with antibody to C-KIT. The number of C-KIT+ mast cells from five random fields per specimen were compared under light microscopy (200x). RESULTS: Overall, the number of C-KIT+ mast cells was significantly lower in gastric wall specimens from cases of idiopathic GP when compared with controls or cases of secondary GP irrespective of the sites of sampling (P<.01, analysis of variance test) with the distribution of cells being uniform and unique for each stomach. CONCLUSION: A lack of C-KIT+ mast cells may underlie the development of idiopathic GP in neonates.

Gastric Mucosa↗
PubMed1999

Hyaluronic acid: a specific prognostic indicator of hepatic damage in biliary atresia.

BACKGROUND/PURPOSE: Hepatic fibrosis can progress in biliary atresia (BA) and is associated with capillarization of hepatic sinusoids. The significance of serum hyaluronic acid (HA) as a noninvasive indicator of histological sinusoidal endothelial cell (SEC) damage and hepatic fibrosis in BA, is investigated. METHODS: A total of 28 postoperative BA patients (mean age, 11.0+/-3.7 years) and 20 normal controls (mean age, 10.5+/-2.8 years) were studied. BA patients were divided into group I, good liver function (n = 8); group II, moderate liver dysfunction (n = 10); and group III, severe liver dysfunction (n = 10). Serum HA was determined using a one-step sandwich enzyme immunoassay, and liver histological damage was confirmed immunohistochemically using an antibody against factor VIII-related antigen (FVIIIRAg), which is specific for detecting damaged SEC. RESULTS: Serum HA was significantly higher (P < .0001) in group III (84.6+/-36.5 ng/mL) than in group I (15.9+/-6.9 ng/mL) or group 11 (28.7+/-10.7 ng/mL). Although immunoreactive products of FVIIIRAg were abundant in group III, they were not detected in SEC from group II. CONCLUSION: Serum HA may be of value for monitoring postoperative BA patients as a noninvasive indicator of SEC damage and progressive hepatic fibrosis.

Adolescent↗
PubMed1999

Modified soave pull-through for Hirschsprung's disease: intraoperative internal sphincterotomy.

BACKGROUND/PURPOSE: Anorectal achalasia (AA) may persist after pull-through (PT) for Hirschsprung's disease (HD), which may cause postoperative enterocolitis (POE) and constipation. The authors modified the Soave PT (modified Soave PT, MSPT) to eliminate AA, and present their results. METHODS: This was a 16-year retrospective review of 43 patients with histologically proven HD of the rectosigmoid or sigmoid colon treated by MSPT. The MSPT involves excision of the posterior rectal cuff and an intraoperative internal sphincterotomy, allowing the PT colon to fit nicely. RESULTS: Mean age at MSPT was 16.7 months (16 were < or =3 months old [37%]; 7 were neonates [16%]). Mean follow-up was 9.2 years. Six of 43 cases (14%) had preoperative enterocolitis; only 2 of 43 (5%) had single episodes of POE. At review, 37 of 43 were older than 4 years; 29 (78%) had normal bowel function (14 had experienced soiling after MSPT, which resolved after a mean of 6.4 years); and 8 (21%) had problematic bowel function: 3 had occasional soiling, 1 had soiling only before defecation, 3 (8%) had constipation requiring laxatives or enemas, and 1 had significant soiling. CONCLUSION: MSPT is safe and may contribute to a reduction in the incidence of POE and constipation.

Digestive System Surgical Procedures↗
PubMed1999

Fetal esophageal transplantation in rats: a treatment option for long-gap esophageal atresia.

PURPOSE: The aim of this study is to determine if fetal esophageal transplantation can create viable esophageal tissue that may be used for treating long gap esophageal atresia. METHODS: Fetuses of gestational age 19 to 20 days were obtained by hysterotomy of pregnant 15-week-old Lewis rats. A 10-mm long segment of esophagus was obtained from each fetus by thoracolaparotomy and transplanted by wrapping it in a pouch created in the distal omentum of a 5-week-old Lewis rat (syngeneic transplantation: n = 15). Transplanted fetal esophageal grafts were harvested 10 days post-transplantation and fixed in 10% formalin and embedded in paraffin. H&E was used for histological examination, and PGP 9.5 (a neuronal antibody) was used for immunohistochemistry. Esophageal segments obtained from 10-day-old Lewis rats were used as controls. RESULTS: Thirteen of 15 (87%) grafts were transplanted successfully. The successfully transplanted graft could be mobilized to the thoracic cavity without tension or compromising of vascularity, because of the long omental pedicle. H&E staining and PGP 9.5 immunohistochemistry showed normal esophageal structure with intact esophageal nervous system, comparable with control specimens. CONCLUSIONS: Fetal esophageal transplantation produces viable esophageal tissue that may find application for treating long gap esophageal atresia providing rejection can be controlled adequately.

Animals↗
PubMed1999

Complications after sigmoidocolocystoplasty: review of 100 cases at one institution.

BACKGROUND/PURPOSE: The aim of this study was to review complications after sigmoidocolocystoplasty (SCP) performed at a single institution from 1984 to 1997. METHODS: The medical records of 100 patients who underwent SCP were reviewed retrospectively. RESULTS: Mean age at SCP was 10.8 years. Urinary control was improved in 75 cases and unchanged in 25. Post-SCP complications included death, abdominal wound infection or dehiscence, adhesive bowel obstruction, vesical calculi, vesicocolonic anastomosis stenosis, metabolic acidosis, and transient renal hypertension. Fifty-one patients underwent ureteric re-implantation (URI) at the time of, or before, SCP, and 7 had recurrence of VUR post-URI (spontaneous regression in 6); 3 patients had new onset of contralateral VUR post-URI (spontaneous regression in 2). Transient pleural effusion was seen after reinsertion of ventriculo-pleural shunts to ventriculo-thoracic in 12 cases, but there was no incidence of infection. Squamous metaplasia of the bladder mucosa was identified in 5 patients on routine mucosal biopsy results but resolved in all cases after regular bladder irrigation was commenced. Preoperative constipation or fecal incontinence was better managed after sigmoidectomy in approximately one third of cases (38%). CONCLUSIONS: SCP with or without URI can improve the quality of life of patients with neurogenic or small-capacity bladder, but it can be associated with long-term complications. Regular bladder irrigation is recommended to maintain bladder mucosa integrity.

Adolescent↗
PubMed1999

'Stab and Split': a 'bloodless' and 'scarless' skin incision technique for minor surgery.

The 'stab and split' skin incision technique was applied to children requiring minor surgery. A small stab incision was made on a skin crease and split open with mosquito forceps. After the surgical procedure was completed, the wound was closed in layers with a subcuticular suture to the skin. In all cases, splitting caused virtually no blood loss because subcutaneous veins were left intact, and the wounds healed well, especially in infants. 'Stab and split' is an effective alternative incision technique for minor surgery in younger children.

Child↗
PubMed1998

Pedicled external spermatic fascia flap for urethroplasty in hypospadias and closure of urethrocutaneous fistula.

PURPOSE: To prevent the development of urethrocutaneous fistula after urethroplasty for hypospadias or recurrence after closure of a urethrocutaneous fistula, the authors developed a new simple technique wherein the readily available external spermatic fascia (ESF) surrounding the testis and cord is used as a pedicled blanket flap to cover the neourethra or the site of closure of a urethrocutaneous fistula. RESULTS: In three patients who had urethroplasty for hypospadias incorporating our ESF flap procedure, no urethrocutaneous fistula developed. It was also effective for closure of urethrocutaneous fistula in five patients, some of whom had had recurrent fistula formation.

Adult↗
PubMed1998

A case of zinc chloride ingestion.

Zinc chloride is a powerful corrosive agent. Reports of zinc chloride ingestion are uncommon, and there is little information about its toxicity and management. The authors report the clinical course of a 10-year-old girl who accidentally ingested an acid soldering flux solution (pH, 3.0; zinc chloride, 30% to < 60%). Systemic effects after the ingestion were unremarkable except for lethargy. Thus, chelation therapy was not considered. Severe gastric corrosion was caused by local caustic action. An antral stricture of the stomach approximately 3 weeks after the ingestion developed, and she underwent a modified Heineke-Mikulicz antropyloroplasty. Postoperatively, she made an uneventful recovery. On follow-up, although she was tolerating a normal diet, results of a barium meal showed her stomach to be totally aperistaltic. Results of a nuclear medicine study showed moderately delayed gastric emptying. Careful long-term follow-up is necessary, because there is potential risk for malignancy in the damaged stomach.

Burns, Chemical↗