Prevalence of human cystic echinococcosis in the towns of Ñorquinco and Ramos Mexia in Rio Negro Province, Argentina, and direct risk factors for infection.

BACKGROUND: Cystic echinococcosis (CE) is a parasitic zoonosis caused by infection with the larval stage of Echinococcus granulosus (s.l.). This study investigated the prevalence and potential risk factors associated with human CE in the towns and rural areas of Ñorquinco and Ramos Mexia, Rio Negro province, Argentina. METHODS: To detect abdominal CE cysts, we screened 892 volunteers by ultrasound and investigated potential risk factors for CE using a standardized questionnaire. Prevalence ratio (PR) with 95% confidence intervals (CI) was used to measure the association between CE and the factors investigated, applying bivariate and multivariate analyses. RESULTS: Abdominal CE was detected in 42/892 screened volunteers (4.7%, 95% CI 3.2-6.1), only two of whom were under 15 years of age. Thirteen (30.9%) CE cases had 25 cysts in active stages (CE1, CE2, CE3a, according to the WHO Informal Working Group on Echinococcosis [WHO-IWGE] classification). The most relevant risk factors identified in the bivariate analysis included: living in rural areas (P = 0.003), age > 40 years (P = 0.000), always drinking water from natural sources (P = 0.007), residing in rural areas during the first 5 years of life (P = 0.000) and having lived more than 20 years at the current address (P = 0.013). In the multivariate final model, the statistically significant risk factors were: frequently touching dogs (P = 0.012), residing in rural areas during the first 5 years of life (P = 0.004), smoking (P = 0.000), age > 60 years (P = 0.002) and living in rural areas (P = 0.017). CONCLUSIONS: Our results point toward infection with CE being acquired since childhood and with constant exposure throughout life, especially in rural areas with a general environmental contamination.

Genetic characterization of human hydatid cysts shows coinfection by Echinococcus canadensis G7 and Echinococcus granulosus sensu stricto G1 in Argentina.

Human cystic echinococcosis caused by the larval stage of Echinococcus granulosus sensu lato (s.l.) is a highly endemic disease in the province of Neuquén, Patagonia, Argentina. Human infections with E. granulosus sensu stricto (s.s.) G1 and Echinococcus canadensis G6 were reported in Neuquén in previous studies, whereas four genotypes were identified in livestock: G1, G3, G6, and G7. The aim of this study was to identify the genotypes of E. granulosus s.l. isolates from humans of Neuquén province, Patagonia, Argentina, through the 2005-2014 period. Twenty six hydatid cysts were obtained from 21 patients. The most frequent locations were the liver and lungs. Single cysts were observed in 81.0% of patients, and combined infection of liver and lungs was detected in 9.5% of cases. Partial sequencing of mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes identified the presence of E. granulosus s.s. G1 (n = 11; 42.3%) including three different partial sequences; E. canadensis G6 (n = 14; 53.8%) and E. canadensis G7 (n = 1; 3.9%). Coinfection with G1 and G7 genotypes was detected in one patient who harbored three liver cysts. Most of the liver cysts corresponded to G1 and G6 genotypes. This study presents the first report in the Americas of a human infection with E. canadensis G7 and the second worldwide report of a coinfection with two different species and genotypes of E. granulosus s.l in humans. The molecular diversity of this parasite should be considered to redesign or improve the control program strategies in endemic regions.

A community-based study to examine the epidemiology of human cystic echinococcosis in Rio Negro Province, Argentina.

Although cystic echinococcosis (CE) is an important public health problem in Rio Negro Province, current epidemiological data for CE, in this region of Argentina, are not available. Therefore, a community-based study, which incorporated diagnostic imaging and a questionnaire, was conducted in Ingeniero Jacobacci, a small town in southern Rio Negro Province. This study sought to assess the prevalence of human CE, in the study population, and to evaluate epidemiologic factors associated with CE transmission within the study area. Of the 560 individuals who volunteered to participate in the study, 189 (34%) were children and 371 (66%) were adults. All study participants were screened for CE using abdominal ultrasound scanning, with CE-positive or suspect individuals also receiving thoracic radiographs. The overall prevalence of CE was 7.1% (40/560), with 1.6% (3/189) of children, and 10% (37/371) of adults diagnosed as CE-positive. Although 92.5% (37/40) of the CE-positive individuals had only hepatic lesions, two participants had both hepatic and pulmonary lesions, and one participant had a single renal lesion. Approximately 92% (340/371) of the adult study participants completed the questionnaire, which was used to identify factors associated with an increased risk for human infection. Age, level of education, dog ownership, and contact with sheep were found to be significantly associated with CE status. This study demonstrated that CE continues to be highly endemic in this region of Rio Negro Province, Argentina. In addition, community-based ultrasound screening surveys are a noninvasive, effective approach to case detection at the community level.

Correlación anátomo tomográfica de la vena cava superior izquierda persistente / Anatomy and CT correlation of persistent left superior vena cava

Introducción: La vena cava superior izquierda es un hallazgo incidental en la mayoría de los casos y representa la persistencia de la vena cardinal anterior izquierda embriológica. Es la anomalía venosa intratorácica más común. Se halla entre el 0,1 y el 0,3% de las personas normales y hasta en el 10% de los que presentan alguna malformación cardíaca congénita. Habitualmente, desemboca en la aurícula derecha a través del seno coronario y en alrededor del 70% de los casos está comunicada con la vena cava superior derecha por el tronco venoso innominado. Objetivo: Correlacionar anatomía y tomografía computada de la vena cava superior izquierda persistente. Materiales y métodos: Para la realización de la presente comunicación, se utilizaron un cadáver adulto, conservado en formaldehído al 10% en el que, durante la disección del bloque cardiopulmonar, se reconoció una vena cava superior izquierda; y un conjunto de imágenes tomográficas en las que también aparece dicha anomalía. Se realizó la correlación anátomoimagenológica correspondiente. Discusión: Mediante imágenes de tomografía computada se logró reconocer claramente la vena cava superior izquierda. Además, pudo lograrse una excelente correlación anátomoimagenológica de la estructura considerada. Conclusiones: La presencia de una doble vena cava se podría sospechar ante la aparición de un arco rectificado de la arteria pulmonar izquierda en la radiografía de tórax, ó también, de manera incidental al realizarse una tomografía o unecocardiograma. Cabe destacar la importancia de este hallazgo tanto desde el punto de vista de la imagenología como desde su implicancia clínica.

Introduction: The left superior vena cava is an incidental finding in most cases and represents the persistence of the embryologic left anterior cardinal vein. It is the most common intrathoracic venous anomaly. It lies between 0.1 and 0.3 % of normal people and up to 10 % of those with a congenital heart defect. Usually empties into the right atrium through the coronary sinus and in about 70 % of cases are reported to the right superior vena cava by the brachiocephalic vein. Objective: Correlate anatomy and computed tomography persistent left superior vena cava. Materials and methods: To achieve this communication, we used adult corpse, preserved in 10% formaldehyde in which, during dissection of the heart lung block was recognized the left superior vena cava, and a set of tomographic images in the it alsoappears that anomaly. Correlation was performed for anatomic imagenological. Discussion: Using tomographic images were also recognized clearly the left superior vena cava. Furthermore, an excellent correlation was achieved anatomic imagenological considered structure. Conclusions: The presence of a double vena cava could be suspected in the occurrence of an arc grinding of the left pulmonary artery in the chest radiograph, or also, incidentally when performing a tomographic or echocardiogram. Note the importance of this finding from the point of view of the imaging and from its clinical implication.

Apendicitis del muñón apendicular / Appendicitis of the appendicular stump

La apendicitis del muñón es una entidad rara, caracterizada por un proceso inflamatorio del remanente apendicular luego de una apendicectomía incompleta. Los signos y síntomas no difieren de una apendicitis aguda. Al no ser una patología usualmente pensada como posible diagnóstico diferencial del abdomen agudo inflamatorio, tiene mayor riesgo de complicaciones y morbi-mortalidad. Los métodos seccionales de diagnósticos por imágenes resultan muy beneficiosos para definir el diagnóstico. La ultrasonografía (US) y tomografía computada (TC)demuestran signos similares a los observados en cuadros habituales de inflamación aguda del apéndice cecal. Se presentan dos casos de apendicitis del muñón, uno de ellos recibió tratamiento quirúrgico y el otro tratamiento médico...

Cirugía conservadora en hidatidosis esplénica / Conservative surgery in splenic hydatidic disease

La esplenectomía es la operación más frecuente en la hidatidosis esplénica, sea por el tamaño del quiste o porque aún no hay suficiente difusión de la cirugía conservadora. El trabajo se refiere a 7 pacientes en los que se efectuaron 6 adventicectomías y una resección del polo inferior del bazo, sin complicaciones referidas a la técnica conservadora. Se discuten las distintas operaciones, la experiencia de otros centros y se concluye que la cirugía conservadora tiende a reemplazar a la clásica esplenectomía