Maria Mercês Santos
University of São Paulo
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Revista Brasileira De Fisioterapia | 2009
Maria Mercês Santos; Mpc Silva; L. Sanada; Crj Alves
OBJECTIVES: To test the interrater agreement of photogrammetry used to assess postural alignment among children. METHODS: Thirtythree variables were measured from images of 122 healthy children aged seven to ten years, that is, 58 boys (8.39±0.97 years) and 64 girls (8.42±1.06 years). A digital camera (Sony® 6.0 MP DSC-T9) was positioned on a tripod (Vanguard VT-131) at a height of 90 cm and at a distance of 300 cm from the child. The anatomical points of interest were marked with colored adhesives (Pimaco®) on polystyrene spheres of 1 cm in diameter. The children were photographed wearing a bathing suit, in the upright position, in the anterior, posterior, lateral right and lateral left views. Each photograph was analyzed by three previously trained raters using the postural assessment software SAPo. The statistical software SASS/STAT v. 9 was used to obtain the interclass correlation coefficients (ICC). RESULTS: The results showed excellent interrater agreement (ICC>0.90) for 28 variables (84.85%) and good agreement (0.80>ICC>0.89) for five variables (15.15%), even with rigorous classification. CONCLUSION: This method was shown to be viable and to have the potential to generate reference data on postural alignment among children.
Journal of Pediatric Surgery | 2003
Maria Mercês Santos; Uenis Tannuri; João Gilberto Maksoud
BACKGROUND/PURPOSE After surgical correction of gastroschisis, intestinal transitory hypoperistalsis usually occurs. Long-term parenteral nutrition often is necessary leading to a higher morbidity associated with this malformation. The etiology of this transitory intestinal hypomotility is unknown. It may be caused by a reversible inflammatory process in the intestinal wall or other causes, including an alteration of the maturation of intestinal neural plexus, because the disturbance disappears spontaneously after a variable period. The aim of this work was to study the neuronal cells of the myenteric plexus of the fetal intestine in experimental gastroschisis. The main hypothesis was that the transitory intestinal dismotility seen in gastroschisis could be secondary to alteration in the maturation of the enteric nervous plexus. METHODS Twenty-seven time-mated rabbits, on gestational day 25, were submitted to a midline laparotomy; the gravid bicornuate uterus was exposed and opened, and the more distal fetuses relative to the vaginal opening had the abdominal wall opened by a small incision to produce gastroschisis (n = 29). The fetuses not submitted to gastroschisis were used as controls (n = 12). The amniotic fluid was carefully aspirated from the opened uterus and saved for later repositions. On gestational day 30, the does were again submitted to general anesthesia, and the fetuses were delivered by cesarean section. The fetal intestine was removed, the adjacent mesentery excised, and intestinal specimens were harvested for histologic studies. The specimens were stained for acetyl-cholinesterase activity (AChE) to assess the maturity of the nervous enteric cells and for lactate dehydrogenase (LDH) that identify specifically immature nervous cells. The histologic sections stained by LDH were submitted to histomorphometric analysis of the nervous cells through an image system analysis (Kontron 300). The results were submitted to statistical analyses (P <.05). RESULTS Macroscopic alterations of the fetal gastroschisis intestine are similar to the human findings: shortening of the intestine, intestinal wall thickening, and a hypertrophied muscular layer. In the gastroschisis group, histologic AChE activity was decreased in comparison with control intestines. The histomorphometric assessment in slices stained with LDH, which identify immature nervous cells, showed that the neuronal intestinal cells of the gastroschisis group were significantly smaller and more numerous relative to the control group. CONCLUSIONS There were significant differences in the nervous plexus of the intestine of fetuses with gastroschisis relative to the controls. The observed morphologic changes may be caused by alteration in the maturation of the intestinal neuronal in gastroschisis. This alteration may explain the transitory intestinal hypomotility observed in infants after surgical correction of gastroschisis.
Transplantation Proceedings | 2011
Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Luiz Roberto Schlaich Ricardi; Maria Mercês Santos; João Gilberto Maksoud-Filho; M.L. Pinho-Apezzato; M. M. Silva; Manoel Carlos Prieto Velhote; Ali A. Ayoub; Wagner de Castro Andrade; Antonio José Gonçalves Leal; Helena T. Miyatani; Uenis Tannuri
OBJECTIVE The objective of this study was to report our experience with pediatric orthotopic liver transplantation (OLT) with living related donors. METHODS We performed a retrospective chart analysis of 121 living related donor liver transplantations (LRDLT) from June 1998 to June 2010. RESULTS Indications were biliary atresia (BA; n = 81), primary sclerosing cholangitis (n = 5), α-1 antitrypsin deficiency (n = 4); cholestasis (n = 9), fulminant hepatic failure (n = 8), autoimmune hepatitis (n = 2), Alagille syndrome (n = 4), hepatoblastoma (n = 3), tyrosinemia (n = 2), and congenital hepatic fibrosis (n = 3). The age of the recipients ranged from 7-174 months (median, 22) and the weights ranged from 6-58 kg (median, 10). Forty-nine children (40.5%) weighed ≤10 kg. The grafts included the left lateral segment (n = 108), the left lobe (n = 12), and the right lobe (n = 1). The donors included 71 mothers, 45 fathers, 2 uncles, 1 grandmother, 1 grandfather, and 1 sister with a median age of 29 years (range, 16-53 ys) and a median weight of 68 kg (range, 47-106). Sixteen patients (12.9%) required retransplantation, most commonly due to hepatic artery thrombosis (HAT; n = 13; 10.7%). The other complications were biliary stenosis (n = 25; 20.6%), portal vein thrombosis (PVT; n = 11; 9.1%), portal vein stenosis (n = 5; 4.1%), hepatic vein stenosis (n = 6; 4.9%), and lymphoproliferative disorders (n = 8; 6.6%). The ultimate survival rate of recipients was 90.3% after 1 year and 75.8% after 3 years. Causes of early death within 1 month were HAT (n = 6), PVT (n = 2), severe graft dysfunction (n = 1), sepsis (n = 1), and intraoperative death in children with acute liver failure (n = 2). Causes of late deaths included lymphoproliferative disease (n = 3), chronic rejection (n = 2), biliary complications (n = 3), and recurrent disease (n = 3; hepatoblastoma and primary sclerosing cholangitis). CONCLUSIONS Despite the heightened possibility of complications (mainly vascular), LRDLT represented a good alternative to transplantation from cadaveric donors in pediatric populations. It was associated with a high survival ratio.
Transplantation Proceedings | 2009
Nelson Elias Mendes Gibelli; Uenis Tannuri; M.L. Pinho-Apezzato; Ana Cristina Aoun Tannuri; João Gilberto Maksoud-Filho; Wagner de Castro Andrade; Manoel Carlos Prieto Velhote; Maria Mercês Santos; Ali A. Ayoub; M. Marques da Silva
BACKGROUND AND AIMS Liver transplantation (OLT) in children has seen significant improvements in recent years. Long-term immunosuppressive strategies have focused on avoiding the risks of long-term immunosuppression, particularly nephrotoxicity, de novo malignancy and late infections. Since its introduction in renal transplantation in 1999, sirolimus (SRL) has been used by an increasing number of liver transplant centers. The aim of this study was to review the experience using SRL in pediatric liver transplant recipients at a single center. METHODS Between 1989 and 2006, 318 children underwent OLT including 13 who were converted to SRL therapy because of tacrolimus-related side effects. The indications were posttransplant lymphoproliferative disease (PTLD; n = 11), nephrotoxicity (n = 1), and de novo autoimmune hepatitis (n = 1). One patient with PTLD previously concurrently displayed chronic rejection. SRL dosages ranged between 0.4 and 5 mg/d. The median duration of follow-up was 18 months. RESULTS PTLD recurred in 1 patient. There were no episodes of acute rejection. One child developed hyperlipidemia that resolved with diet and medication. CONCLUSIONS Conversion from tacrolimus to SRL in selected pediatric liver transplant recipients is safe. Children with PTLD may benefit from immunosuppression with SRL after liver transplantation.
Pediatric Surgery International | 2008
Maria Mercês Santos; Uenis Tannuri; Maria Cecília Mendonça Coelho
Although the utility of the acetylcholinesterase (AChE) histochemistry on rectal suction biopsy in diagnosing Hirschsprung’s disease (HD) has been documented, few reports address a great number of biopsies and patients. Our aim is to present a 17-year experience on the method of rectal suction biopsy and AChE histochemical staining for diagnosis of intestinal dysganglionoses. Between August 1989 and July 2006, 297 children suspected of having HD were submitted to rectal suction biopsies that were evaluated by the same two surgeons. There were 18 complications (6.0%), namely one self-limited rectal bleeding and 17 (5.7%) inadequate procedures that were repeated. A total of 157 patients (52.8%) showed no increased AChE activity and the remaining patients (140–47.2.0%) presented patterns of increased AChE activity confirming the diagnosis of HD or neuronal intestinal dysplasia. Among the 140 cases suspected as having HD, in 131 children the diagnosis of HD was confirmed and they were operated on. The histological studies showed that 111 children presented the classic form of HD or a long spastic segment. Sixteen children presented total colonic aganglionosis and four children proved to have intestinal neuronal dysplasia, according to histological and radiological criteria. Nine (6.6%) newborns were identified as false-positives and no false-negative results were verified. The rectal suction biopsy combined with AChE staining is advantageous for the differentiation between normal bowel and intestinal dysganglionoses. The rectal suction method is simple and can easily be performed by experienced surgeons. The histological evaluation is very objective and can be performed by a non-pathologist.
Transplantation Proceedings | 2010
M.L. Pinho-Apezzato; Uenis Tannuri; Ana Cristina Aoun Tannuri; Evandro Sobroza de Mello; F. Lima; Nelson Elias Mendes Gibelli; Maria Mercês Santos; Ali A. Ayoub; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; M. M. Silva; Wagner de Castro Andrade; Helena T. Miyatani
Posttransplantation lymphoproliferative disorder (PTLD) is a serious complication following solid organ transplantation that has been linked to Epstein-Barr virus (EBV) infection. The aim of this article was to describe a single-center experience with the multiplicity of clinical presentations of PTLD. Among 350 liver transplantations performed in 303 children, 13 survivor children displayed a histological diagnosis of PTLD (13/242 survivors; 5.4%). The age at diagnosis ranged from 12 to 258 months (median, 47), and the time from transplantation ranged from 1 to 84 months (median, 13). Ten of these children (76.9%) were EBV-naïve prior to transplantation. Fever was present in all cases. The clinical signs at presentation were anemia (92.3%), diarrhea and vomiting (69.2%), recurrent upper airway infections (38.4%), Waldeyer ring lymphoid tissue hypertrophy (23.0%), abdominal mass lesions (30.7%), massive cervical and mediastinal adenopathy (15.3%), or gastrointestinal and respiratory symptoms (30.7%). One child developed fulminant hepatic allograft failure secondary to graft involvement by PTLD. Polymorphic PTLD was diagnosed in 6 patients; 7 had the diagnosis of lymphoma. Treatment consisted of stopping immunosuppression as well as starting intravenous gancyclovir and anti-CD20 monoclonal antibody therapy. The mortality rate was 53.8%. The clinical presentation of PTLD varied from fever of unknown origin to fulminant hepatic failure. The other symptoms that may be linked to the diagnosis of PTLD are pancytopenia, tonsil and adenoid hypertrophy, cervical or mediastinal lymph node enlargement, as well as abdominal masses. Despite numerous advances, the optimal treatment approach for PTLD is not completely known and the mortality rate is still high.
Transplantation Proceedings | 2011
Ana Cristina Aoun Tannuri; Nelson Elias Mendes Gibelli; Luiz Roberto Schlaich Ricardi; M. M. Silva; Maria Mercês Santos; M.L. Pinho-Apezzato; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; Ali A. Ayoub; Wagner de Castro Andrade; A.N. Backes; Helena T. Miyatani; Uenis Tannuri
INTRODUCTION Biliary atresia (BA) is the leading indication for orthotopic liver transplantation (OLT) among children. However, there are technical difficulties, including the limited dimensions of anatomical structures, hypoplasia and/or thrombosis of the portal vein and previous portoenterostomy procedures. OBJECTIVE The objective of this study was to present our experience of 239 children with BA who underwent OLT between September 1989 and June 2010 compared with OLT performed for other causes. METHODS We performed a retrospective analysis of patient charts and analysis of complications and survival. RESULTS BA was the most common indication for OLT (207/409; 50.6%). The median age of subjects was 26 months (range, 7-192). Their median weight was 11 kg (range, 5-63) with 110 children (53.1%) weighing ≤10 kg. We performed 126 transplantations from cadaveric donors (60.8%) and 81 from living-related donors (LRD) (39.2%). Retransplantation was required for 31 recipients (14.9%), primarily due to hepatic artery thrombosis (HAT; 64.5%). Other complications included the following: portal vein thrombosis (PVT; 13.0%), biliary stenosis and/or fistula (22.2%), bowel perforation (7.0%), and posttransplantation lymphoproliferative disorder (PTLD; 5.3%). Among the cases of OLT for other causes, the median age of recipients was 81 months (range, 11-17 years), which was higher than that for children with BA. Retransplantation was required in 3.5% of these patients (P < .05), mostly due to HAT. The incidences of PVT, bowel perforation, and PTLD were significantly lower (P < .05). There was no significant difference between biliary complications in the 2 groups. The overall survival rates at 1 versus 5 years were 79.7% versus 68.1% for BA, and 81.2% versus 75.7% for other causes, respectively. CONCLUSIONS Children who undergo OLT for BA are younger than those engrafted for other causes, displaying a higher risk of complications and retransplantations.
Transplantation Proceedings | 2011
Nelson Elias Mendes Gibelli; Ana Cristina Aoun Tannuri; Uenis Tannuri; Maria Mercês Santos; M.L. Pinho-Apezzato; João Gilberto Maksoud-Filho; Manoel Carlos Prieto Velhote; Ali A. Ayoub; M. M. Silva; Wagner de Castro Andrade
BACKGROUND/PURPOSE Posttransplantation portal vein thrombosis (PVT) can have severe health consequences, and portal hypertension and other consequences of the long-term privation of portal inflow to the graft may be hazardous, especially in young children. The Rex shunt has been used successfully to treat PVT patients since 1998. In 2007, we started to perform this surgery in patients with idiopathic PVT and late posttransplantation PVT. Herein we have reported our experience with this technique in acute posttransplantation PVT. METHODS Three patients of ages 12, 15, and 18 months underwent cadaveric (n = 1) or living donor (n = 2) orthotopic liver transplantation (OLT). All patients had biliary atresia with portal vein hypoplasia; they developed acute PVT on the first postoperative day. They underwent a mesenteric-portal surgical shunt (Rex shunt) using a left internal jugular vein autograft (n = 2) or cadaveric iliac vein graft (n = 1) on the first postoperative day. RESULTS The 8-month follow-up has confirmed shunt patency by postoperative Doppler ultrasound. There have been no biliary complications to date. CONCLUSIONS The mesenteric-portal shunt (Rex shunt) using an autograft of the left internal jugular or a cadaveric vein graft should be considered for children with acute PVT after OLT. These children usually have small portal veins; reanastomosis is often unsuccessful. In addition, this technique has the advantage to avoid manipulation of the hepatic hilum and biliary anastomosis. Although this study was based on a limited experience, we concluded that this technique is feasible, with great benefits to and low risks for these patients.
Journal of Pediatric Surgery | 2012
Ana Cristina Aoun Tannuri; Maria Cecília Mendonça Coelho; Josiane de Oliveira Gonçalves; Maria Mercês Santos; Luiz Fernando Ferraz da Silva; Israel Bendit; Uenis Tannuri
BACKGROUND/PURPOSE The mechanisms of increased collagen production and liver parenchyma fibrosis are poorly understood. These phenomena are observed mainly in children with biliary obstruction (BO), and in a great number of patients, the evolution to biliary cirrhosis and hepatic failure leads to the need for liver transplantation before adolescence. However, pediatric liver transplantation presents with biliary complications in 20% to 30% of cases in the postoperative period. Intra- or extrahepatic stenosis of bile ducts is frequent and may lead to secondary biliary cirrhosis and the need for retransplantation. It is unknown whether biliary stenosis involving isolated segments or lobes may affect the adjacent nonobstructed lobes by paracrine or endocrine means, leading to fibrosis in this parenchyma. Therefore, the present study aimed to create an experimental model of selective biliary duct ligation in young animals with a subsequent evaluation of the histologic and molecular alterations in liver parenchyma of the obstructed and nonobstructed lobes. METHODS After a pilot study to standardize the surgical procedures, weaning rats underwent ligation of the bile ducts of the median, left lateral, and caudate liver lobes. The bile duct of the right lateral lobe was kept intact. To avoid intrahepatic biliary duct collaterals neoformation, the parenchymal connection between the right lateral and median lobes was clamped. The animals were divided into groups according to the time of death: 1, 2, 3, 4, and 8 weeks after surgical procedure. After death, the median and left lateral lobes (with BO) and the right lateral lobe (without BO [NBO]) were harvested separately. A group of 8 healthy nonoperated on animals served as controls. Liver tissues were subjected to histologic evaluation and quantification of the ductular proliferation and of the portal fibrosis. The expressions of smooth muscle α-actin (α-SMA), desmin, and transforming growth factor β1 genes were studied by molecular analyses (semiquantitative reverse transcriptase-polymerase chain reaction and real-time polymerase chain reaction, a quantitative method). RESULTS Histologic analyses revealed the occurrence of ductular proliferation and collagen formation in the portal spaces of both BO and NBO lobes. These phenomena were observed later in NBO than BO. Bile duct density significantly increased 1 week after duct ligation; it decreased after 2 and 3 weeks and then increased again after 4 and 8 weeks in both BO and NBO lobes. The portal space collagen area increased after 2 weeks in both BO and NBO lobes. After 3 weeks, collagen deposition in BO was even higher, and in NBO, the collagen area started decreasing after 2 weeks. Molecular analyses revealed increased expression of the α-SMA gene in both BO and NBO lobes. The semiquantitative and quantitative methods showed concordant results. CONCLUSIONS The ligation of a duct responsible for biliary drainage of the liver lobe promoted alterations in the parenchyma and in the adjacent nonobstructed parenchyma by paracrine and/or endocrine means. This was supported by histologic findings and increased expression of α-SMA, a protein related to hepatic fibrogenesis.
Journal of Pediatric Surgery | 2014
Ana Cristina Aoun Tannuri; Roberta Figueiredo Monteiro; Maria Mercês Santos; Helena T. Miyatani; Uenis Tannuri
BACKGROUND/AIM Hepatic artery anastomosis (HAA) is the most important aspect of living donor liver transplantation (LDLT), and it is currently performed by a specialized microsurgeon using micro surgical techniques, with interrupted sutures and the aid of an operative microscope. To simplify the procedure, we studied a new, simpler technique performed by pediatric transplant surgeons with continuous sutures and the same 3.5× magnification loupe used during other transplant procedures. The aim of this study was to compare these two hepatic artery reconstruction techniques in two pediatric LDLT series. METHODS This study was initiated in January 2010 and finished in June 2013. In the first period, the arterial reconstruction was performed with an operating microscope and the classical technique of 9-0 separate sutures. In the second period, the arterial reconstruction was performed using a simpler technique, with surgical loupe and continuous 8-0 Prolene sutures. The incidences and outcomes of complications within the two periods were analyzed and compared. RESULTS A total of 82 LDLTs were performed, 38 in the first period and 44 in the second period. There were no differences between the periods, except for the arterial ischemia time, which was lower in the second period. CONCLUSION Hepatic artery anastomosis can be safely performed with low complication rates by a pediatric transplant surgeon using continuous sutures with a 3.5× magnifying loupe. This technique is simpler, less time consuming and simplifies the complex pediatric LDLT procedure.