Tumor miofibroblastico inflamatorio: presentación de dos casos pediátricos / Inflammatory myofibroblastic tumor: presentatiom of two pediatric cases

El tumor miofibroblástico inflamatorio tiene un comportamiento predominantemente benigno pero en ocasiones puede mostrar grados variables de agresividad. Se localiza en diferentes órganos, el pulmón es el sitio más frecuente, seguido por la cavidad abdominal. Se presentan 2 casos con tumor miofibroblástico inflamatorio. Caso N° 1 femenino de 5 años con palidez cutáneo mucosa, hiporexia, dolor abdominal, fiebre, soplo cardíaco y hepatoesplenomegalia. Ultrasonido, tomografía y estudio radiológico contrastado: tumor en cuerpo gástrico con engrosamiento de sus paredes sugestivo de enfermedad linfoproliferativa. Estudio endoscópico: lesión verrugosa, en curvatura mayor y cuerpo alto. Biopsia: no concluyente. Caso N° 2 femenino de 14 años con estreñimiento agudo, dolor abdominal, masa palpable en mesogastrio e hipogastrio. Ultrasonido y tomografía: lesión ocupante de espacio en mesenterio, quística. Las dos pacientes presentaron anemia severa, leucocitosis y trombocitosis. Se realizó laparotomía exploradora en ambas, caso N° 1: tumor sólido en curvatura mayor gástrica, se hizo resección completa mediante gastrectomía parcial. Caso N° 2: tumor que surge del mesocolon transverso, quístico, ocupando todo el abdomen, 90% fue resecado. Diagnosticó histopatológico: tumor miofibroblástico inflamatorio. Evolución satisfactoria en ambos casos. Esta neoplasia debe sospecharse en niños para evitar terapias radicales, la cirugía conservadora es suficiente como tratamiento en la mayoría de los casos

The inflammatory myofibroblastic tumor behaves predominantly benign but can sometimes show varying degrees of aggressiveness. It is located in different organs, the lung is the most frequent, followed by the abdominal cavity. We present 2 cases of inflammatory myofibroblastic tumor. Case No. 1 female 5 years old with pale skin mucosa, anorexia, abdominal pain, fever, heart murmur, and hepatosplenomegaly. Ultrasound, CT and contrast radiological study: tumor in the stomach with thickening of their walls suggestive of lymphoproliferative disease. Endoscopic Study: warty lesion on greater curvature and high body. Biopsy inconclusive. Case No. 2 female 14 years with severe constipation, dominal pain, palpable mass in mesogastrium and hypogastric. Ultrasound and CT: space-occupying lesion in the mesentery, cystic. The two patients had severe anemia, leukocytosis and thrombocytosis. Laparotomy was performed in both Case No. 1: solid tumor greater curvature gastric resection was completed by partial gastrectomy. Case No. 2: tumor that arises from the transverse mesocolon, cystic, occupying the entire abdomen, 90% were resected. Pathological diagnosis: inflammatory myofibroblastic tumor. Satisfactory in both cases. This neoplasm should be suspected in children to prevent radical therapies, surgery, conservative treatment is sufficient in most cases

Hemangiomatosis hepática en lactantes: diagnóstico y evolución. “Hospital J. M. de los Ríos”. Caracas - Venezuela / Hemangiomatosis liver in infants: diagnosis and evolution

Las lesiones vasculares hepáticas en niños son raras pero no infrecuentes en gastroenterología pediátrica. Los hemangiomas son los tumores hepáticos vasculares más frecuentes en la infancia, la mayoría de curso benigno, algunos, incluyendo el hemangioendotelioma infantil, tienen potencial maligno. La clínica predominante es hepatomegalia, dolor abdominal, hemangiomas cutáneos e insuficiencia cardíaca congestiva; y menos frecuente esplenomegalia, ictericia, ascitis, hemorragia digestiva y anemia. Se presentan 5 lactantes entre 1 y 4 meses con diagnóstico de hemangiomatosis hepática; en tres de ellos su diagnóstico fue incidental a través de ecografía, uno presentó aumento de volumen abdominal progresivo y otro hepatomegalia; tres presentaron hemangiomas en piel. Todos cursaron con anemia. Se realizó ecografía describiéndose hepatomegalia, con múltiples imágenes redondeadas, hipoecoicas, de diferentes tamaños, en ambos lóbulos hepáticos; Tomografía axial computada abdominal: hepatomegalia con compromiso de ambos lóbulos, ocupados por áreas nodulares hipodensas. Fueron evaluados por los servicios de endocrinología, cardiología, gastroenterología y cirugía pediátrica. En uno se realizó biopsia hepática. Recibieron tratamiento con prednisona 3 - 4 mg/kg/día con descenso progresivo de la misma, seguimiento clínico y ecográfico durante 1 año. Cuatro pacientes respondieron al tratamiento, evidenciándose disminución e incluso desaparición en tres pacientes de los hemangiomas, y uno no respondió, asociándose propanolol.

Hepatic vascular lesions in children are rare but not uncommon in pediatric gastroenterology. Hemangiomas are the most common vascular liver tumors in childhood, most benign course, some, including infantile hemangioendothelioma, have malignant potential. The clinical manifestations are hepatomegaly, abdominal pain, cutaneous hemangiomas and congestive heart failure and less frequent splenomegaly, jaundice, ascites, gastrointestinal bleeding and anemia. We present five infants between 1 and 4 months with a diagnosis of hepatic hemangiomatosis, in three of them the diagnosis was made incidentally by ultrasonography, showed a progressive increase in abdominal volume and a hepatomegaly, three had skin hemangiomas. All of them presented with anemia. Hepatomegaly describing ultrasound was performed, with multiple images rounded, hypoechoic, of different sizes in both lobes, abdominal computed tomography: hepatomegaly with involvement of both lobes, occupied by hypodense nodular areas. Services were assessed by endocrinology, cardiology, gastroenterology and pediatric surgery. In one a liver biopsy was performed. Treated with prednisone 3-4 mg / kg / day with gradual decrease of the same, clinical and ultrasound for 1 year. Four patients responded to treatment, demonstrating decreased or even disappeared in three patients with hemangiomas, and one did not respond, associating propranolol.

Traumatismo abdominal en niños / Abdominal trauma in children

Se realizó una investigación sobre 171 casos de pacientes ingresados con el diagnóstico de Traumatismo Abdominal, entre el primero de enero de 1988 y el 31 de diciembre de 1994. Se encontró que ocurría una mayor incidencia en los varones escolares procedentes del medio urbano. Con una prevalencia anual casi invariable dentro del rango aproximado de los 24 casos. El promedio de estadía por hospitalización fue de 8,3 días. En 95 por ciento de los casos la evolución fue satisfactoria y solo 5 por ciento de Mortalidad. Los pacientes fueron diagnósticados al ingreso de acuerdo a su estado clínico y tratados médicamente casi todos hasta lograr su estabilización hemodinámica, en solo 70 casos (40 por ciento) estuvo indicada la laparotomía exploradora. Los casos que requirieron intervenciones quirúrgicas se les realizó la reparación de los órganos lesionados adoptando diferentes conductas de acuerdo al órgano y al tipo de lesión. En 19 casos surgieron complicaciones postoperatorias las cuales fueron resueltas satisfactoriamente

The use of FK-506 for small intestine allotransplantation. Inhibition of acute rejection and prevention of fatal graft-versus-host disease.

Small intestine allotransplantation in humans is not yet feasible due to the failure of the current methods of immunosuppression. FK-506, a powerful new immunosuppressive agent that is synergistic with cyclosporine, allows long-term survival of recipients of cardiac, renal, and hepatic allografts. This study compares the effects of FK-506 and cyclosporine on host survival, graft rejection, and graft-versus-host-disease in a rat small intestine transplantation model. Transplants between strongly histoincompatible ACI and Lewis (LEW) strain rats, and their F1 progeny are performed so that graft rejection alone is genetically permitted (F1----LEW) or GVHD alone permitted (LEW----F1) or that both immunologic processes are allowed to occur simultaneously (ACI----LEW). Specific doses of FK-506 result in prolonged graft and host survival in all genetic combinations tested. Furthermore, graft rejection is prevented (ACI----LEW model) or inhibited (rejection only model) and lethal acute GVHD is eliminated. Even at very high doses, cyclosporine did not prevent graft rejection or lethal GVHD, nor did it allow long-term survival of the intestinal graft or the host. Animals receiving low doses of cyclosporine have outcomes similar to the untreated control groups. No toxicity specific to FK-506 is noted, but earlier studies by other investigators suggest otherwise.

Induction of stable chimerism and elimination of graft-versus-host disease by depletion of T lymphocytes from bone marrow using immunomagnetic beads.

The goal of transplantation is the induction of immunologic tolerance. At present, nonspecific immunosuppression is used to prevent graft rejection and, commonly, graft-versus-host disease (GVHD). Nevertheless, nonspecific immunosuppressive therapy is frequently complicated by infection, malignant tumors, and drug toxicity. In order to examine whether hematopoietic chimerism can be used to induce specific allograft tolerance, we have reconstituted lethally irradiated Lewis rats with ACI bone marrow that has been depleted of T cells with use of immunomagnetic beads. This technique consists of binding OX-19, a mouse anti-rat pan-T lymphocyte monoclonal antibody, to magnetic polymer beads. Mixing of bone marrow or splenocytes with the bead/OX-19 complexes, followed by magnetic separation, results in significant depletion of T cells with minimal nonspecific cell loss. Immunomagnetic T-cell depletion of bone marrow, followed by reconstitution of a lethally irradiated host, allows for the development of stable, mixed hematopoietic chimerae without evidence of GVHD. These hosts are immunocompetent by clinical criteria. Recipients of untreated donor bone marrow that did or did not receive nonspecific immunosuppression demonstrated varying degrees of GVHD and reduced survival. The ability to rapidly and simply deplete T lymphocytes from bone marrow and produce stable, immunocompetent hematopoietic chimerae without GVHD may be an important method for tolerance induction to vascularized allografts.

Immunomagnetic T-lymphocyte depletion (ITLD) of rat bone marrow using OX-19 monoclonal antibody.

Graft versus host disease (GVHD) may be abrogated and host survival prolonged by in vitro depletion of T lymphocytes from bone marrow (BM) prior to allotransplantation. Using a mouse anti-rat pan T-lymphocyte monoclonal antibody (OX19) bound to monosized, magnetic, polymer beads, T lymphocytes were removed in vitro from normal bone marrow. The removal of the T lymphocytes was confirmed by flow cytometry. Injection of the T-lymphocyte-depleted bone marrow into fully allogeneic rats prevents the induction of GVHD and prolongs host survival.