Quiste epitelial esplénico gigante, características morfológicas y evolución postoperatoria: reporte de un caso / Epithelial splenic cyst. Morphological characteristics and postoperative evolution: case report

RESUMEN: Los quistes primarios del bazo (QPB), son lesiones poco frecuentes en patología quirúrgica; los mayores de 5 cm o sintomáticos deben ser tratados quirúrgicamente para evitar el riesgo de complicaciones. Se debe realizar un examen histopatológico para confirmar el subtipo de quiste esplénico y descartar una eventual transformación maligna del revestimiento epitelial pluripotencial. El objetivo de este manuscrito fue reportar un caso de QPB intervenido quirúrgicamente y revisar la evidencia existente respecto de sus características morfológicas, terapéuticas y pronósticas. Caso clínico: Se trata de una mujer de 18 años (MAC), que consultó por distensión abdominal progresiva, de varios meses de evolución. La tomografía abdominal reveló la existencia de una masa heterogénea de 21 cm de diámetro mayor, en relación con el colon transverso y la curva mayor gástrica. El examen intraoperatorio reveló una masa sólido-quística que surgía del mesocolon transverso. La cirugía consistió en la esplenectomía y exéresis en bloque del tumor. La paciente evolucionó de forma satisfactoria, dándose de alta al quinto día del postoperatorio. El diagnóstico de quiste epitelial esplénicose estableció en base al examen patológico de la pieza quirúrgica. Cursando su 6º mes postoperatorio sin inconvenientes. Se realizó control tomográfico, que permitió verificar un bazo supernumerario funcionante.

SUMMARY: Primary splenic cysts (PSC) are rare lesions in surgical pathology; those symptomatic, or greater than 5 cm, should be treated surgically to avoid the risk of complications. A histopathological examination should be performed to confirm the splenic cyst subtype and rule out a possible malignant transformation of the pluripotential epithelial lining. The aim of this manuscript was to report a case of PSC who had undergone surgery and to review the existing evidence regarding its morphological, therapeutic and prognostic characteristics. An 18- year-old woman (MAC), consulted for progressive abdominal distention of several months of evolution. Abdominal tomography revealed the existence of a large heterogeneous mass, 21 cm in diameter, in relation to the transverse colon and the greater gastric curve. Intraoperative examination revealed a solid cystic mass arising from the transverse mesocolon. Surgery consisted of splenectomy and in-block excision of the tumor. The patient evolved satisfactorily and was discharged on the fifth postoperative day. Diagnosis of epithelial splenic cyst was established based on the pathological examination of the surgical specimen. At six months postoperative the patient had evolved satisfactorily without complications. Following abdominal tomography control a functioning supernumerary spleen was confirmed.

Clinical and hematological profile in a newborn cohort with hemoglobin SC / Perfil clínico e hematológico em uma coorte neonatal com hemoglobina SC

Abstract Objectives: Hemoglobin SC is the second most common variant of sickle-cell disease worldwide, after hemoglobin SS. The objectives of the study were to describe the clinical and laboratory characteristics of hemoglobin SC disease in children from a newborn screening program and treated at a blood center. Methodology: This study assessed a cohort of 461 infants born between 01/01/1999 and 12/31/2012 and followed-up until 12/31/2014. Clinical events were expressed as rates for 100 patient-years, with 95% confidence intervals. Kaplan-Meier survival curves were created. Results: The median age of patients was 9.2 years; 47.5% were female. Mean values of blood tests were: hemoglobin, 10.5 g/dL; reticulocytes, 3.4%; white blood cells, 11.24 × 109/L; platelets, 337.1 × 109/L; and fetal hemoglobin, 6.3%. Clinical events: acute splenic sequestration in 14.8%, blood transfusion 23.4%, overt stroke in 0.2%. The incidence of painful vaso-occlusive episodes was 51 (48.9-53.4) per 100 patient-years and that of infections, 62.2 episodes (59.8-64.8) per 100 patient-years. Transcranial Doppler ultrasonography (n = 71) was normal given the current reference values for SS patients. Hydroxyurea was given to ten children, all of whom improvement of painful crises. Retinopathy was observed in 20.3% of 59 children who underwent ophthalmoscopy. Avascular necrosis was detected in seven of 12 patients evaluated, predominantly in the left femur. Echocardiogram compatible with pulmonary hypertension was recorded in 4.6% of 130 children, with an estimated average systolic pulmonary artery pressure of 33.5 mmHg. The mortality rate from all causes was 4.3%. Conclusions: Clinical severity is variable in SC hemoglobinopathy. Several children have severe manifestations similar to those with SS disease.

Resumo Objetivos: A hemoglobinopatia SC é a segunda variante mais comum da doença falciforme no mundo, após a hemoglobinopatia SS. Os objetivos do estudo foram descrever as características clínicas e laboratoriais da hemoglobinopatia SC em recém-nascidos diagnosticados por programa de triagem neonatal e encaminhados para acompanhamento em hemocentro. Metodologia: Coorte de 461 recém-nascidos SC nascidos entre 01/01/1999 e 31/12/2012 e seguidos até 31/12/2014. A incidência de eventos clínicos foi expressa por taxas relativas a 100 pacientes-ano, com limites de confiança a 95%. Curvas de sobrevida foram construídas segundo Kaplan-Meier. Resultados: Mediana de idade, 9,2 anos; 47,5%, feminino. Médias dos valores hematológicos: hemoglobina 10,5 g/dL; reticulócitos 3,4%; leucometria 11,24 x 109/L; plaquetometria 337,1x109/L; hemoglobina fetal 6,3%. Eventos clínicos: sequestro esplênico agudo em 14,8%, hemotransfusão 23,4%, AVC isquêmico 0,2%. A incidência de episódios vaso-oclusivos dolorosos foi de 51 (48,9-53,4) por 100 pacientes-ano; a de infecções, 62,2 episódios (59,8-64,8) por 100 pacientes-ano. Doppler transcraniano (n = 71) foi normal, se usados os valores de referência de crianças SS. Dez pacientes usaram hidroxiureia, todos com melhoria das crises dolorosas. Retinopatia foi observada em 20,3% das 59 crianças que fizeram fundoscopia. Necrose avascular foi detectada em 7 de 12 pacientes avaliados, com predomínio no fêmur esquerdo. Ecocardiograma compatível com hipertensão pulmonar foi registrado em 4,6% de 130 crianças, com média estimada de 33,5 mm Hg de pressão arterial pulmonar. A taxa de mortalidade por todas as causas foi de 4,3%. Conclusões: A hemoglobinopatia SC tem gravidade variável; várias crianças apresentam manifestações clínicas intensas, semelhantes às da hemoglobinopatia SS.

Rol de la cirugía en el manejo de la infección invasora por Saprochaete capitata / Role of surgery in Saprochaete capitata (S. capitata) sepsis in a patient with acute myeloid leukemia

Saprochaete capitata (S. capitata) fungal sepsis is a severe condition with a clinical presentation that is similar to other yeast originated fungal sepsis. It is observed in patients with hematological malignancies such as acute myeloid leukemia and neutropenia. We report a 23 year old male presenting with cough, fever and malaise. A bone marrow biopsy led to the diagnosis of acute myeloid leukemia. During the first cycle of chemotherapy the patient presented fever: blood cultures were positive for Klebsiella pneumoniae. Despite antimicrobial treatment, fever persisted; a computed tomography showed a focal splenic lesion; a left exudative pleural effusion appeared. A Matrix Assisted Laser Desorption Ionization-Time of Flight mass spectrometry identified the presence of S. capitata. After multiple antifungal treatments and pleural cavity cleansing by means of videothoracoscopy and laparoscopic splenectomy, the infection resolved and the patient completed his chemotherapy.

REDUCE PORT LAPAROSCOPIC SPLENECTOMY FOR GIANT EPITELIAL CYST / ESPLENECTOMIA LAPAROSCÓPICA COM PORTAIS REDUZIDOS PARA TRATAR CISTO EPITELIAL GIGANTE

Background: Delaitre and Maignien performed the first successful laparoscopic splenectomy in 1991. After that, laparoscopic splenectomy has become one of the most frequently performed laparoscopic solid organ procedures. Aim: To demonstrate the surgical techique of laparoscopic splenetomy with reduced portals. Methods: A reduce port laparoscopic splenectomy was performed by using a 10 mm and two 5 mm trocars. To entered the abdomen a trans-umbilical open technique was done and a 10 mm trocar was placed. A subcostal 5 mm trocar was placed under direct vision at the level of the anterior axillary line and another 5 mm port was inserted at the mid-epigastric region. Once it was completely dissected and freed from all of its attachments the hilum, splenic artery and vein, was clipped with hem-o-lock and divided with scissors. Then an endobag was used to retrieve the spleen after being morcellated trough the umbilical incision. Results: This technique was used in a 15 years old female with epigastric and left upper quadrant pain. An abdominal ultrasound demonstrated a giant cyst located in the spleen. Laboratory tests findings were normal. The CT scan was also done, and showed a giant cyst, which squeeze the stomach. The patient tolerated well the procedure, with an unremarkable postoperative. She was discharge home 72 h after the surgery. Conclusion: The use of reduce port minimizes abdominal trauma and has the hypothetical advantages of shorter postoperative stay, greater pain control, and better cosmesis. Laparoscopic splenectomy for giant cysts by using reduce port trocars is safe and feasible and less invasive.

Racional: Delaitre e Maignien realizaram a primeira esplenectomia laparoscópica bem sucedida em 1991. Depois disso, a esplenectomia laparoscópica tornou-se um dos procedimentos laparoscópicos de órgãos sólidos mais frequentemente realizadas. Objetivo: Demonstrar a técnica cirúrgica de esplenectomia laparoscópica com portais reduzidos. Métodos: A esplenectomia laparoscópica reduzida em potais foi realizada usando um trocarte de 10 mm e dois de 5 mm. A entrada abdominal se dá pela técnica aberta trans-umbilical e um trocarte de 10 mm foi aí colocado. Um de 5 mm subcostal foi colocado sob visão direta no nível da linha axilar anterior e outra trocarte de 5 mm foi inserido na região médio-epigástrica. Uma vez completamente dissecado e liberado todos os seus ligamentos do hilo, a artéria e veia esplênicas foram ligadas com hem-o-lock e seccionado com tesoura. Em seguida, um Endobag foi usado para retirar o baço após ser ele morcelado através da incisão umbilical. Resultado: Esta técnica foi utilizada em uma jovem de 15 anos com dor epigástrica e em hipocôndrio esquerdo. Ultrassom abdominal mostrou um cisto gigante localizado no baço. Exames complementares tiveram resultados normais. TC mostrou um cisto gigante, que projetava-se para o estômago. A paciente tolerou bem o procedimento, com pós-operatório normal. Ela teve alta hospitalar em 72 h após a operação. Conclusão: A diminuição de portais minimiza o trauma abdominal e tem as vantagens conhecidas de menor tempo de pós-operatório, maior controle da dor, e melhor efeito cosmético. A esplenectomia laparoscópica para cistos gigantes usando trocárteres reduzidos é segura, viável e menos invasiva.

Pyoderma gangrenosum with renal and splenic impairment - case report / Manifestacao esplenica e renal do pioderma gangrenoso - relato de caso

Pyoderma gangrenosum is an uncommon and recurrent neutrophilic dermatosis of unknown cause. The lesions usually start as tender sterile papulopustules or erythematous nodules that undergo necrosis followed by ulceration. The lower limbs are most commonly affected and around half of the cases are associated with systemic disorders. Although rare, cases of pyoderma gangrenosum with extramucocutaneous sterile neutrophilic infiltrate have been reported, with the lungs being the most commonly affected organ. We report a case of pyoderma gangrenosum with splenic and renal impairment. Pyoderma gangrenosum should be considered a multisystemic disease with classic cutaneous manifestations and potential involvement of internal organs.

Pioderma gangrenoso é uma dermatose neutrofílica incomum, recorrente e de etiologia desconhecida. As lesões geralmente se iniciam como papulopústulas estéreis ou nódulos eritematosos que sofrem necrose seguida de ulceração. Os membros inferiores são mais comumente afetados e quase a metade dos casos está associada a doenças sistêmicas. Apesar de raros, casos de pioderma gangrenoso com infiltrado neutrofílico estéril extramucocutâneo foram relatados e os pulmões são os órgãos mais comumente acometidos. Nós relatamos um caso de manifestação esplênica e renal do pioderma gangrenoso. Pioderma gangrenoso deve ser considerado doença multissistêmica com manifestações cutâneas clássicas e potencial envolvimento de órgãos internos.

Imaging techniques and histology in the evaluation of liver fibrosis in hepatosplenic schistosomiasis mansoni in Brazil: a comparative study

Few publications have compared ultrasound (US) to histology in diagnosing schistosomiasis-induced liver fibrosis (LF); none has used magnetic resonance (MR). The aim of this study was to evaluate schistosomal LF using these three methods. Fourteen patients with hepatosplenic schistosomiasis admitted to hospital for surgical treatment of variceal bleeding were investigated. They were submitted to upper digestive endoscopy, US, MR and wedge liver biopsy. The World Health Organization protocol for US in schistosomiasis was used. Hepatic fibrosis was classified as absent, slight, moderate or intense. Histology and MR confirmed Symmers' fibrosis in all cases. US failed to detect it in one patient. Moderate agreement was found comparing US to MR; poor agreement was found when US or MR were compared to histology. Re-classifying LF as only slight or intense created moderate agreement between imaging techniques and histology. Histomorphometry did not separate slight from intense LF. Two patients with advanced hepatosplenic schistosomiasis presented slight LF. Our data suggest that the presence of the characteristic periportal fibrosis, diagnosed by US, MR or histology, associated with a sign of portal hypertension, defines the severity of the disease. We conclude that imaging techniques are reliable to define the presence of LF but fail in grading its intensity.

Correlation of biological serum markers with the degree of hepatic fibrosis and necroinflammatory activity in hepatitis C and schistosomiasis patients

Liver biopsy is the gold-standard method to stage fibrosis; however, it is an invasive procedure and is potentially dangerous. The main objective of this study was to evaluate biological markers, such as cytokines IL-13, IFN-ã, TNF-á and TGF-â, platelets, bilirubins (Bil), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), total proteins, ã-glutamil transferase (ã-GT) and alkaline phosphatase (AP), that could be used to predict the severity of hepatic fibrosis in schistosomiasis and hepatitis C (HC) as isolated diseases or co-infections. The following patient groups were selected: HC (n = 39), HC/hepatosplenic schistosomiasis (HSS) (n = 19), HSS (n = 22) and a control group (n = 13). ANOVA and ROC curves were used for statistical analysis. P < 0.05 was considered significant. With HC patients we showed that TNF-á (p = 0.020) and AP (p = 0.005) could differentiate mild and severe fibrosis. With regard to necroinflammatory activity, AST (p = 0.002), ã-GT (p = 0.034) and AP (p = 0.001) were the best markers to differentiate mild and severe activity. In HC + HSS patients, total Bil (p = 0.008) was capable of differentiating between mild and severe fibrosis. In conclusion, our study was able to suggest biological markers that are non-invasive candidates to evaluate fibrosis and necroinflammatory activity in HC and HC + HSS.

Utilidad y complicaciones de la biopsia percutánea esplénica con aguja tru-cut guiada por imágenes / Ultrasound guided needle biopsy of the spleen: review of 13 procedures

Background: Needle biopsies of the spleen were avoided due to the fear of bleeding in a highly vascularized organ. However their safety, even using 18 gauge needles, has been demonstrated. Aim: To report the experience with ultrasound guided needle biopsies of the spleen. Material and Methods: Retrospective review of records of ultrasound guided biopsies of the spleen using Tru-cutTM needles, performed between 2005 and 2009. Results: Thirteen procedures performed in 12 patients were identified. A specific diagnosis was achieved in nine (69 percent) procedures (lymphoma in four, melanoma in 2, sarcoma in 1, extremedullary erythropoiesis in one and splenic cryptococcosis in one. Two patients with negative results were subjected to a new biopsy, which yielded the diagnosis of lymphoma. A third patient was studied elsewhere, finding a malignant tumor. Two patients had complications, one had a vagal reaction and other had a perisplenic hematoma without clinical repercussion. Conclusions: Ultrasound guided needle biopsy of the spleen is a safe and useful procedure.

Objetivo: Reportar la experiencia de biopsias percutáneas esplénicas con aguja tru-cut guiadas por imágenes. Materiales y Métodos: Revisión retrospectiva de biopsias esplénicas con aguja tru-cut guiadas por ultrasonido (US) y tomografía computada (TC) realizadas en nuestro hospital desde Enero de 2005 a Abril de 2009. Resultados: Se identificaron un total de 13 procedimientos. La biopsia percutánea logró un diagnóstico específico en 9 (69 por ciento) de las 13 intervenciones. Los diagnósticos fueron linfoma (n = 4), melanoma (n = 2), sarcoma (n = 1), hematopoyesis extramedular (n = 1) y criptococosis esplénica (n = 1). De las biopsias no diagnósticas 3 casos correspondieron a patología neoplásica y uno a patología benigna. Se reportaron 2 complicaciones (15 por ciento). Discusión: La biopsia esplénica percutánea guiada por imágenes con aguja tru-cut es un procedimiento útil y seguro, capaz de determinar el diagnóstico definitivo en la mayoría de los pacientes y evitar la mayoría de las esplenectomías diagnósticas.

Bazo accesorio intrapancreático / Intrapancreatic accesory spleen

Existen pocos informes de bazo intrapancreático accesorio y algunos asociados a quistes epiteliales. Suelen cursar asintomáticos y confundirse con tumores neuroendocrinos no funcionantes o adenocarcinoma de páncreas, debido a su características radiológicos y a la inespecifidad de los síntomas. Nosotros reportamos un paciente de sexo masculino que se documentó una lesión de 3 cm en la cola del páncreas en la T.A.C. de abdomen y posteriormente confirmada por la R.M.N. Se llevó a cabo una pancreatectomía distal sin esplenectomía. El diagnóstico definitivo de patología fue un bazo intrapanacreático accesorio.

There are fews reports of intrapancreatic accessory spleen and some refer epithelial cysts. Most of these lesions are asymptomatic and my be misdiagnosed as a non-functioning neuroendocrine tumor or pancreas adenocarcinoma, due to their radiological characteristic and lack of symptomatology. We reported one male patient with a 3 cm lesion in the tail of the pancreas on computed tomography scan and later confirmed with RMN. A pancreatectomy distal without splenectomy performed. The final pathological diagnosis eas a intrapancreatic accessory spleen.

Importance of TNF-alpha in the course of acute infection with Trypanosoma cruzi: influence of its inhibition by pentoxifylline treatment

Infection of C3H/He mice with the Peruvian strain of Trypanosoma cruzi (Biodeme type I, Z2b), a macrophagotropic strain, determined severe parasitism of macrophages, necrosis of the spleen, and high host mortality. In the present study, pentoxifylline (PTX), an inhibitor of TNF-alpha was investigated on its action upon splenic necrosis, parasitemia and host survival. Immunohistochemical data suggested the importance of this cytokine in parasite destruction and decreasing of parasitemia, although paradoxically contributing to the high mortality of infected mice. Necrotic lesions involving several organs, specially the heart, in acute Chagas disease, are important aggravating factors, increasing cardiac morbidity. Advantage of inhibiting TNF-alpha action was herein investigated. Infected mice were divided into two groups: untreated (n = 24), and PTX treated mice (n = 25). PTX was administered in two daily doses of 30 mg/kg/bw, by intraperitoneal route. Normal controls either treated with PTX or saline were also included. Histopathology of the spleen and in situ immunolabeling of TNF-alpha, using anti-TNF-alpha monoclonal antibody, were performed. Necrotic areas were evaluated by morphometry. Mice treated with PTX showed a significant decrease of necrotic areas and diminution of TNF-alpha expression in spleen tissue, suggesting that PTX treatment could control TNF-alpha effects, and thus be used as an adjuvant in the treatment of acute Chagas' disease.

Inflammatory pseudotumor of the spleen concomitant with renal cell carcinoma: case report

CONTEXTO: Pseudotumor inflamatório é uma lesão benigna rara que pode se desenvolver em uma grande variedade de órgãos. Sua grande importância na prática médica reside na enorme dificuldade de distingui-lo tanto clinicamente quanto radiologicamente de condições malignas. RELATO DE CASO: Os autores relatam um caso de pseudotumor envolvendo o baço e apresentando-se concomitantemente a um carcinoma renal de células claras. Apesar da semelhança macroscópica a tumores malignos, as características inflamatórias do pseudotumor são facilmente evidenciadas à microscopia. Apesar de hipóteses terem sido formuladas, os mecanismos patogenéticos relacionados ao pseudotumor ainda não estão bem estabelecidos.

Pathology of the spleen in hepatosplenic schistosomiasis. Morphometric evaluation and extracellular matrix changes

Histological, ultrastructural, morphometric and immunohistochemical data obtained from the study of spleens removed by splenectomy from 34 patients with advanced hepatosplenic schistosomiasis revealed that the main alterations were congestive dilatation of the venous sinuses and diffuse thickening of the splenic cords. Splenic cord thickening was due to an increase of its matrix components, especially type IV collagen and laminin, with the conspicuous absence of interstitial collagens, either of type I or type III. Deposition of interstitial collagens (types I and III) occurred in scattered, small focal areas of the red pulp, but in the outside of the walls of the venous sinuses, in lymph follicles, marginal zone, in the vicinity of fibrous trabeculae and in sidero-sclerotic nodules. However, fibrosis was not a prominent change in schistosomal splenomegaly and thus the designation "fibro-congestive splenomegaly" seems inadequate. Lymph follicles exhibited variable degrees of atrophy, hyperplasia and fibrous replacement, sometimes all of them seen in different follicles of the same spleen and even in the same examined section. Changes in white pulp did not seem to greatly contribute to increasing spleen size and weight, when compared to the much more significant red pulp enlargement

Splenic cysts - a Jamaican experience

A total of eleven (11) cases of non-parasitic splenic cysts have been studied at the University Hospital of the West Indies by routine haematoxylin and eosine and immunohistochemcial staining, using epithelial markers (cytokeratin, low molecular weight keratin and epithelial membrane antigen). The majority (eight of eleven) were found to epithelial or true cysts. This is in contrast to findings previously reported in the literature, based on light microscopic examination, that the majority of splenic cysts are non-epithelial in origin. We therefore suggest that immunohistochemical studies should be used routinely to accurately define the nature of all splenic cysts.

Cisticercose musculo-cutanea e visceral: doenca rara? / Musculocutaneous and visceral cysticercosis: a rare disease?

O presente trabalho teve como objetivos estimar a frequencia das formas musculo-cutanea e visceral da cisticercose em exames anatomo-patologicos e necropsias realizados em Brasilia, Distrito Federal (estudo retrospectivo) e diagnosticar a cisticercose musculo-cutanea em pacientes residentes na mesma regiao geografica (estudo prospectivo). Em 64.911 protocolos de exames anatomo-patologicos, o diagnostico de cisticercose foi observado em 30 (0,05 por cento), sendo que em 27 (90,0 por cento) os cistos estavam nos tecidos musculo-cutaneo-mucoso, em 1 (3,3 por cento) em ganglio e em 2 (6,7 por cento) no sistema nervoso central. Entre aqueles com cistos nos tecidos musculo-cutaneo-mucoso 2 (7,4 por cento) tinham cisticercos em lingua. Em 1520 protocolos de necropsia, encontraram-se 25 (1,6 por cento) com diagnostico de cisticercose, sendo: 24 (96,0 por cento) com neurocisticercose, seja isolada ou associada a outras formas da doenca; e 2 (8,0 por cento) com cisticercos em coracao, 2 (8,0 por cento) em musculo esqueletico e 1 (4,0 por cento) em figado, seja isolados ou associados a outras localizacoes do parasito. Foram tambem examinados 1122 individuos, realizando-se em todos eles as reacoes sorologicas de imunofluorescencia indireta e ELISA para cisticercose e a investigacao radiologica de partes mole do cranio...

Cisto epidermóide do baço / Epidermoid cyst of the spleen

O cisto epidermóide é uma forma rara de cisto näo parasitário do baço; caracteriza-se por ser revestido, ao menos em parte, por epitélio estratificado plano, sem anexos cutâneos. Relata-se um caso de cisto epidermóide de baço em paciente masculino, de 19 anos de idade, submetido a laparotomia para investigaçäo de esplenomegalia com lesäo parenquimatosa, de menor ecogenicidade a ultra-sonografia. Este parece ser o primeiro cisto epidermóide descrito na literatura médica brasileira. Faz-se breve discussäo dos principais aspectos anatomopatológicos, patogenéticos, clínicos, diagnósticos e terapêuticos desta rara entidade

Treatment of acute experimental schistosomiasis

A model of acute schistosomiasis of the mouse was used to observe whether curative treatment would be followed by an enhancement of the hepatic and splenic lesions, as a consequence of the massive destruction of worms and eggs within the portal system. Mice infected with 50 cercariae of Schistosoma mansoni were treated with both oxamniquine and praziquantel on the 50th day of infection and submitted to a sequential histologic examination from the 2nd to the 45th day after treatment. Although severe focal lesions due to dead and disintegranting worms were present in the livers of the treated animals, no aggravation of the general changes (reative hepatitis and splenitis, or periovular granulomas) was seen in comparison with a control non-treated group. Of 50 animals treated during the acute phase of schistosomiasis only one died espontaneously, while 16 ou of 30 infected controls died before the end of the experiment. The present investigation indicates that curative treatment during the acute phase of schistosomiasis does not enhance previous lesions at first and results in progressive disappearance of the lesions starting six days following chemotherapy