Estudio morfocuantitativo de protoescólices y otras estructuras fundamentales de Echinococcus granulosus en hospederos humanos / Morphoquantitative study of protoscolices and other fundamental structures of Echinococcus granulosus in human hosts

La equinococosis quística (EQ) a pesar de ser una enfermedad endémica en diversos lugares del planeta, presenta pocos estudios morfológicos y cuantitativos de las estructuras fundamentales del Echinococcus granulosus en humanos, en especial de los protoescólices. El objetivo de este estudio fue analizar morfocuantitativamente protoescólices y otras estructuras fundamentales de E. granulosus obtenidos de hospederos humanos. Estudio de corte transversal. Se estudiaron 8 especímenes de EQ hepática humana, aplicando un muestreo no probabilístico por conveniencia. Se evaluó las capas quísticas, el líquido y la arenilla hidatídica. Las capas fueron fijadas en formaldehido tamponado a 10 % y procesadas para su inclusión en paraplast. Se realizaron cortes de 5 µm de grosor y fueron teñidas con H-E para su análisis con microscopía óptica. El líquido y arenilla fueron centrifugados y al sedimento obtenido se le realizó análisis directo para determinar las medidas morfométricas de los protoescólices y de los ganchos grandes y pequeños. Se utilizó estadística descriptiva. De los 8 quistes estudiados, 6 eran quistes univesicular, uno multivesicular y un quiste abscedado, cuyas capas laminada y germinativa se encontraban bien definidas. Las vesículas prolígeras presentaban forma redondeada con protoescólices en su interior. Los protoescólices invaginados presentaron un largo y ancho promedio de 140,8 ± 34,3 µm y 106,2 ± 29,5 µm, respectivamente; y los desarrollados un largo de 237,2 ± 53,0 µm y ancho de 128,7 ± 32,0 µm. Los ganchos rostelares presentaron contornos suaves distribuidos en dos filas regulares. El promedio del largo total de los ganchos grandes y pequeños fue 20,1 ± 2,7 µm; el promedio del ancho total fue 7,4 ± 1,2 µm. En conclusión, las características morfocuantitativas de los ganchos de E. granulosus en humanos, son distintos a otras especies hospederas intermediarias y de otros Echinococcus spp. Es posible que el abandono del estado de resistencia de los protoescólices invaginado hasta su desarrollo genere implicancias epidemiológicas de interés.

SUMMARY: Although cystic echinococcosis (CE) is an endemic disease in several parts of the world, few morphological and quantitative studies of the fundamental structures of Echinococcus granulosus in humans, especially protoscolices. The aim of this study was to perform a morphoquantitative analysis of protoescolex and other fundamental structures of E. granulosus from human hosts. Cross- sectional study. Eight human hepatic EQ specimens were studied, applying non-probabilistic convenience sampling. Cystic layers, fluid and hydatid grit were evaluated. The layers were fixed in 10% buffered formaldehyde and processed for embedding in paraplast. Slices of 5 µm thickness were made and stained with H-E for light microscopic analysis. The liquid and grit were centrifuged and the sediment obtained was analyzed directly to determine the morphometric measurements of the protoscolices and the large and small hooks. Descriptive statistics were used. Of the 8 cysts studied, 6 were univesicular cysts, one multivesicular and one abscessed cyst, whose lamellar and germinative layers were well defined. The proligerous vesicles had a rounded shape with protoscolices inside. The invaginated protoscolices had an average length and width of 140.8 ± 34.3 µm and 106.2 ± 29.5 µm, respectively; and the developed ones had a length of 237.2 ± 53.0 µm and width of 128.7 ± 32.0 µm. The rostellar hooks presented smooth contours distributed in two regular rows. The average total length of the large and small hooks was 20.1 ± 2.7 µm; the average total width was 7.4 ± 1.2 µm. In conclusion, the morphoquantitative characteristics of E. granulosus hooks in humans are distinct from other intermediate host species and from other Echinococcus spp. It is possible that the abandonment of the resistance state of the invaginated protoscolices until their development generates epidemiological implications of interest.

In-vitro evaluation of Nigella sativa and Punica granatum effect on protoscolices of hydatid cysts / Avaliação in vitro do efeito de Nigella sativa e Punica granatum em protoescólices de cistos hidáticos

Abstract Cystic echinococcosis (CE) are commonly found in the liver and lungs of affected hosts. The treatment approach is usually surgical, or giving drugs in conjunction before surgery to kill protoscolices, to avoid anaphylactic shock from leakage of hydatid fluid into the peritoneum and to decrease opportunities for recurrences. The present study was to evaluate the in vitro scolicidal efficacy of hydroalcoholic extract of Punica granatum peel and Nigella sativa, on the protoscolices of CE that collected from the lungs of infected camels. Different concentrations of extracts with different exposure times were used and a viability assay was applied to measure the scolicidal effect. N. sativa showed its highest scolicidal efficacy at 100 mg/mL and 10 mg/mL concentrations after 30 and 60 min. P. granatum peel extract showed its maximum scolicidal efficacy at 100 mg/mL concentration after 120 min. All experiments of the current study revealed that the extracts of both N. sativa and P. granatum had a scolicidal effects on the protoscolices of camel hydatid cysts. It could be concluded that N. sativa extract is more potent than P. granatum peel extract regarding scolicidal effect, but the efficacies of both extracts were of moderate significant correlation to exposure time and concentrations.

Resumo Os cistos hidáticos (equinococose cística, CE) são comumente encontrados no fígado e nos pulmões dos hospedeiros afetados. A abordagem do tratamento geralmente é cirúrgica, e algumas drogas são administradas em conjunto antes da cirurgia para matar protoscólices e evitar choque anafilático devido ao vazamento de fluido hidático no peritônio e diminuir as oportunidades de recorrência. O presente estudo foi avaliar a eficácia in-vitro do extrato hidroalcoólico de casca de Punica granatum e Nigella sativa, sobre os protoescólices de cistos hidáticos, que foram coletados dos pulmões de camelos infectados. Concentrações dos extratos com diferentes tempos de exposição foram utilizados e um ensaio de viabilidade foi aplicado para medir o efeito escolicida. A N. sativa apresentou sua maior eficácia escolicida nas concentrações de 100 mg/mL e 10 mg/mL após 30 e 60 min. O extrato de casca de P. granatum mostrou sua máxima eficácia escolicida na concentração de 100 mg/mL após 120 min. Todos os experimentos do presente estudo revelaram que os extratos de N. sativa e P. granatum tiveram efeito escolicida dependente da dose e do tempo nos protoescólices dos cistos hidáticos de camelo. Pode-se concluir que o extrato de N. sativa é mais potente que o extrato de casca de P. granatum em relação ao efeito escolicida, mas a eficácia de ambos os extratos foi de correlação significativa moderada com o tempo de exposição e as concentrações.