Prurito anal en niños cubanos con dipylidiosis / Anal pruritus in Cuban children with dipylidiasis

Introducción: La dipylidiosis es una zoonosis parasitaria producida por Dipylidium caninum. La infección es más frecuente en niños que en adultos debido al estrecho contacto de los primeros con mascotas (perros y gatos). La dipylidiosis es una enfermedad benigna y autolimitada, generalmente cursa de manera asintomática, aunque en ocasiones pueden aparecer algunos síntomas. Objetivo: Exponer el caso de niños cubanos con prurito anal, forma clínica poco frecuente de presentación de la dipylidiosis. Presentación de casos: Se trata de cuatro niños de La Habana, Cuba, atendidos en la atención primaria y secundaria de salud por presentar prurito anal, acompañado de la expulsión de elementos blanquecinos móviles en las deposiciones. Se les realizó estudios de las heces y técnica de Graham, con resultados negativos. La falta de diagnóstico etiológico de una posible parasitosis, propició la remisión de los casos al Laboratorio Nacional de Referencia de Parasitología del Instituto de Medicina Tropical Pedro Kouri donde se interrogó a las madres y se indicaron exámenes de las heces, que identificaron D. caninum. Conclusión: Ante niños con prurito anal, forma clínica de presentación poco frecuente de la dipylidiosis, es necesario hacer el diagnóstico diferencial de esta taeniosis zoonótica y solicitar el diagnóstico parasitológico para confirmar la parasitosis. Los resultados negativos obtenidos en la atención primaria y secundaria de salud, hacen sospechar el desconocimiento del diagnóstico de esta zoonosis parasitaria en la red nacional de salud, que, además, produjo demora de dicho diagnóstico y su confirmación en el nivel terciario de salud(AU)

Introduction: Dipylidiasis is a parasitic zoonosis produced by Dipylidium caninum. The infection is more frequent in children than in adults due to the close contact of children with pets (dogs and cats). Dipylidiasis is a benign and self-limiting disease, usually occurs asymptomatically, although sometimes some symptoms may appear. Objective: Present the case of Cuban children with anal pruritus, a rare clinical form of presentation for dipylidiasis. Presentation of cases: Four children from Havana, Cuba, treated in primary and secondary health care services after presenting anal pruritus, accompanied by the withdraw of mobile whitish elements in the stools. Stool studies and Graham's technique were performed, with negative results. The lack of etiological diagnosis of a possible parasitosis, led to the referral of the cases to the National Reference Laboratory of Parasitology of Pedro Kouri Institute of Tropical Medicine where the mothers were questioned and stool tests were indicated, which identified D. caninum. Conclusion: In children with anal pruritus, a rare clinical form of presentation of dipylidiasis, it is necessary to make the differential diagnosis of this zoonotic taeniosis and request the parasitological diagnosis to confirm this parasitosis. The negative results obtained in primary and secondary health care services make suspect the ignorance of the diagnosis of this zoonotic taeniosis in the national health network, which, in addition, produced delay in the diagnosis and its confirmation at the tertiary level of health(AU)

The catholic taste of broad tapeworms - multiple routes to human infection.

Broad tapeworms (Cestoda: Diphyllobothriidea) are the principal agents of widespread food-borne cestodosis. Diphyllobothriosis and diplogonoporosis, caused by members of the genera Diphyllobothrium, Diplogonoporus and Adenocephalus, are the most common fish cestodoses with an estimated 20million people infected worldwide, and has seen recent (re)emergences in Europe due to the increasing popularity of eating raw or undercooked fish. Sparganosis is a debilitating and potentially lethal disease caused by the larvae of the genus Spirometra, which occurs throughout much of the (sub)tropics and is caused by the consumption of raw snakes and frogs, and drinking water contaminated by infected copepods. Both diseases are caused by several species, but the frequency by which the transition to humans has occurred has never been studied. Using a phylogenetic framework of 30 species based on large and small nuclear ribosomal RNA subunits (ssrDNA, lsrDNA), large subunit mitochondrial ribosomal RNA (rrnL) and cytochrome c oxidase subunit I (cox1), we hypothesize that humans have been acquired asaccidental hosts four times across the tree of life of diphyllobothriideans. However, polytomies prevent an unambiguous reconstruction of the evolution of intermediate and definitive host use. The broad host spectrum and the frequency with which switching between major host groups appears to have occurred, may hold the answer as to why accidental human infection occurred multiple times across the phylogeny of diphyllobothriideans. In this study Diplogonoporus is determined to be the junior synonym of Diphyllobothrium. Furthermore, we divide the latter polyphyletic genus into (i) the resurrected genus Dibothriocephalus to include freshwater and terrestrial species including Dibothriocephalus dendriticus, Dibothriocephalus latus and Dibothriocephalus nihonkaiensis as the most common parasites of humans, and (ii) the genus Diphyllobothrium to accommodate parasites from cetaceans including the type species Diphyllobothrium stemmacephalum and Diphyllobothrium balaenopterae n. comb. known also from humans. The non-monophyletic aggregate of marine species from seals is provisionally considered as incertae sedis.

A case of Dipylidium caninum infection in a child from the southeastern Poland.

Dipylidium caninum is a common intestinal tapeworm of dogs, cats and foxes. However, it occasionally infects also humans. We present a case of D. caninum infection in a 2-year-old child living in the Subcarpathian province. The infection was asymptomatic in the first months. The symptoms of abdominal pains, sleep disorders, loss of appetite, hyperactivity and occasional slimy stools appeared later. Proglottids on the underwear, in water while bathing and mobile proglottids passed with the stool were also observed. Prior to appropriate diagnosis the child was treated with pyrantelum (Pyrantelum) and albendazolum (Zentel). However, proglottids were found again in the stool after a few days. We examined stool samples and perianal smears collected from the child and his family. The stool samples were tested by coproscopic methods. Direct methods (direct preparation in 0.9% sodium chloride and in Lugol's solution, Kato thick smear) and concentration methods (decantation with distilled water and Faust's zinc sulphate centrifugal flotation) were used. In the stool samples taken from the child, we observed D. caninum proglottids demonstrating lateral genital pores and many packets of eggs containing from one to a few, mostly 3 to 4 eggs. In the direct preparations in 0.9% sodium chloride and in Lugol's solution single packets with D. caninum eggs were detected. In decantation preparations many D. caninum egg packets were observed. It has to be reported that the child's mother was infected with Giardia intestinalis. Dipylidiasis in humans is a rarely encountered infection in Poland and the diagnosis may be difficult. For these reasons we reported clinical case presentation, diagnostics, treatment and epidemiology of D. caninum infection. We have shown that concentration methods such as decantation might be very helpful in the diagnosis of dipylidiasis.

[Human plerocercoidosis and sparganosis: I. A historical review on aetiology].

Plerocercoid should not be confused with Sparganum. The scolex of plerocercoid has a bothrium or bothrial slit but there is no true scolex in sparganum. Plerocercoid is a developmental stage of an animal tapeworm, genus Spirometra. Sparganum is another generic name of a pseudophyllidean cestode. Plerocercoid causes benign plerocercoidosis and sparganum causes "malignant sparganosis". Plerocercoidosis is a parasitic zoonosis which can be food-borne, water-borne, contact-borne or mother-borne. During the past 20 years, there has been significant progress in studies of human plerocercoidosis and sparganosis, especially the former. Spirometra erinacei-europiea plerocercoidosis and sparganosis prolifera distributed mainly in East Asia. Spirometra mansonoides plerocercoidosis has been reported from the USA. Up to the present, approximately 1400 cases of plerocercoidosis were reported from China, Japan, Korea, USA and Thailand, and at least 16 well-documented cases of human proliferating sparganosis were reported worldwide (in Japan, China, Thailand, USA, Paraguay, Venezuela, and the Philippines). The life cycle of Sparganum is unknown. For plerocercoid, human being acts as a dead-end hosts, copepod and frogs serve as intermediate hosts, and snakes and carnivorous animals are its paratenic hosts. This review summarizes the research progress on aetiology and pathogenesis of human plerocercoidosis and sparganosis. The second part (in press) will be concentrated on their pathology, clinical manifestations, diagnosis, treatment, epidemiology, control and prevention.

The occurrence of Caryophyllaeus laticeps in the nase Chondrostoma nasus from Austrian rivers: possible anthropogenic factors.

Between April 2003 and November 2006 a total of 198 nase Chondrostoma nasus (L.) were examined for parasites from seven river sites in Austria. The selected sites showed different levels of anthropogenic alterations in river morphology ranging from pristine areas, with minor anthropogenic alterations, to strongly physically altered rivers. A variety of parasites were recovered from the skin, gills, swimbladder and eyes, with Caryophyllaeus laticeps (Pallas) being identified as the only cestode species occurring in the intestine. This is the first record of this species in nase in Austria. Caryophyllaeus laticeps was confined to the first 20% of the intestine, even in heavily infected hosts. The occurrence of C. laticeps within the fish population seems to be correlated with the degree of anthropogenic changes of the nase's habitat. In rivers with a high degree of ecological integrity or in rivers that are only partially dammed, C. laticeps is either absent in C. nasus or occurs with low prevalence (5.6-20%) and low mean intensity values (1.0-4.0). Where anthropogenic factors have changed the entire river into a reservoir, and fish cannot escape, the prevalence of infection with C. laticeps increases from 46.2 to 78.2% and the mean intensity from 8.8 to 17.2.

Estructura del quiste hidatídico producido por Echinococcus oligarthrus en el hospedero intermediario Proechimys c.f. guairae (rata espinosa) en Casanare, Colombia / Structure of hydatid cyst due to Echinococcus oligarthrus in the intermediary host Proechimys c.f. guairae in Casanare, Colombia

La equinococosis es un parasitismo grave producto en el hombre y en los animales por larvas de tenias del género Echinococcus que se desarrollan en el hígado, el pulmón, el bazo y en otras víceras y tejidos. De las cuatro tenias del género Echinococcus, tres se presentan en Suramérica: E. granulosus, E. volgeli y E. oligarthrus. En Colombia se han informado casos en humanos y en animales cuyo agente etiológico más frecuente es E. vogeli. En este trabajo presentamos la estructura macroscópica, microscópica y de microscopía electrónica de barrido de quistes hidatídicos múltiples y de sus protoescólices encontrados en un Proechimys c.f. guairae o rata espinosa, capturado en la vereda La Plata del muncicipio de Pore, Casanare, durante la búsqueda del reservorios del virus de la encefalitis equina venezolana. En la autopsia del animal se encontraron quistes múltiples en el hígado, el bazo y el pulmón la gran mayoría fértiles. Están constituidos por una pared franjeada que origina cápsulas prolígeras dentro de las cuales están los protoescólices. El protoescólex es el escólex inmaduro del parásito adulto formado por cuatro ventosas y un rostelo con ganchos, cuyo tamaño y morfología corresponden con las medidas de E. Oligarthrus. Ilustramos las características morfológicas de las larvas, el desarrollo de los protoescólices y revisamos las características de la equinococosis en Colombia

Influence of host weight, sex and reproductive status on helminth parasites of the wild rabbit, Oryctolagus cuniculus, in Navarra, Spain.

A study was carried out in Navarra (northern Spain) on the influence of the weight, sex and reproductive status (lactant, pregnant or lactant + pregnant females and testicular weight for males) of the wild rabbit (Oryctolagus cuniculus) on two cestodes species: Andrya cuniculi and Mosgovoyia ctenoides and four intestinal nematodes: Graphidium strigosum, Trichostrongylus retortaeformis, Nematodiroides zembrae and Dermatoxys hispaniensis. A significantly higher prevalence of A. cuniculi was detected in lactant + pregnant females compared with non-breeding females. Trichostrongylus retortaeformis and N. zembrae showed a significantly higher mean intensity in lactant and lactant + pregnant females than in non-reproductive females. Trichostrongylus retortaeformis presented a higher mean intensity in females than in males, and the mean intensity of the same parasite species was significantly lower in active and inactive males compared with lactant and lactant + pregnant females. There were no significant differences between sexes in the prevalence of helminth parasites. No significant correlation was detected between host weight and the intensity (of infection) of helminths studied. No significant differences in the prevalence and mean intensity of the two cestode species were observed in the three weight categories studied (kittens, juveniles and adults). The prevalence of G. strigosum and mean intensity of T. retortaeformis were significantly higher in older heavier animals than in juveniles.

Infección por dypilidium caninum en un lactante / A case of infection by dypilidium caninum in an infant

Dypilidium caninum es un cestode común en perros y gatos distribuido en todo el mundo. El ser humano, huesped accidental, adquiere la infección a través de las pulgas en asociación con las mascotas infectadas, siendo esta enfermedad más frecuente en niños. Presentamos el caso de una niña de un año y medio de edad, que durante siete meses eliminó proglótidas en las deposiciones, consultando en numerosas oportunidades siendo tratada con fármacos dirigidos a protozoos y nematelmintos. Finalmente, luego de la identificación del Dypilidium caninum se trató a la paciente con niclosamida, evolucionando satisfactoriamente

Caracterización epidemiológica de la equinococosis/hidatidosis en Zacatecas, México / Epidemiological characterization of echinococcosis/hydatidosis in Zacatecas, Mexico

El objetivo de este trabajo fue la elaboración de un modelo epidemiológico de la enfermedad bajo las circunstancias presentes en Zacatecas. La primera fase tuvo lugar en el rastro municipal de la ciudad de Zacatecas, de mayo a agosto de 1990, mediante la identificación del metacestodo de E. granulosus y su fertilidad evaluada por la presencia de arenilla hidatídica; en la segunda, se efectuó un seguimiento a las comunidades de origen de animales con hidatidosis. Se encontraron 190 animales infectados (3.1 por ciento); 188 eran cerdos (99 por ciento) y 2 bovinos (1 por ciento); los órganos afectados fueron: hígado (99 por ciento) y pulmón (1 por ciento). El 19 por ciento de los quistes fueron fértiles. De los cerdos afectados 159 (83.7 por ciento) procedían del estado de Zacatecas, el municipio del mismo nombre tuvo el mayor número de casos (42.8 por ciento). Se analizaron los factores que permiten la subsistencia de la enfermedad y que conforman el modelo epidemiológico

[The causes of the formation of an intensive focus of triaenophoriasis in the upper Tuloma River reservoir]. / O prichinakh formirovaniia intensivnogo ochaga trienoforoza v Verkhnetulomskom vodokhranilishche.

Observations on the Triaenophorus crassus invasion in Coregonus lavaretus and Esox lucius were carried out in the period of 1984 to 1989 in the upper Tuloma River [correction of Verkhnetulomsk] water reservoir and Pechozero water body (the Pecha River) which form a common basin. Significant differences were noted in the infection rate of fishes with this parasite in the above water bodies. In Pechozero, where there are preserved natural conditions and therefore an ecological equilibrium in the host-parasite system, T. crassus is not abundant and the infection rate of C. lavaretus and E. lucius with this parasite is low. In the upper Tuloma River [correction of Verkhnetulomsk] water reservoir, due to the dropping out of the amphipod group of benthos from the biocoenosis of the water body, there has been formed a close ecological connection between copepods, C. lavaretus and E. lucius that resulted in the increase of T. crassus and gave rise to Triaenophorus infection of C. lavaretus here.

Pathogenesis of helminths in equines.

This review summarizes information on the clinical signs, gross and microscopic lesions associated with nematode and cestode infections and discusses the development of these conditions in the equine host.

Raillietina cesticillus: variability of infections in experimentally infected chickens.

In experimental Raillietina cesticillus infections in chickens, the age of cysticercoids, the method by which the cysticercoids are administered and prior starvation of the host are factors that influence the development of infections.

Factors influencing the establishment of Mesocestoides corti in mice following oral inoculation of tetrathyridia.

Factors which influence the establishment of tetrathyridia of Mesocestoides corti in mice following inoculation per os were examined. Only a proportion of the tetrathyridia penetrate the gut wall and gain access to the peritoneal cavity and liver, and most of these penetrate through the wall of the small intestine. It appears that tetrathyridia must attach to the intestinal mucosa and commence penetration immediately or they pass into the large intestine and are voided. Establishment was not influenced by strain, sex or age of host. However, the temperature at which tetrathyridia were maintained before inoculation influence their ability to penetrate the intestinal wall. Additionally it appears that tetrathyridia have to undergo a morphological change before or during, this penetration phase.