Review of "Echinococcus and Echinococcosis, Part A." edited by R. C. Andrew Thompson, Alan J. Lymbery and Peter Deplazes

What do we know about the epidemiology and the management of human echinococcosis in Albania?

Echinococcosis is a life-threatening neglected zoonotic disease. Cystic echinococcosis (CE) due to Echinococcus (E.) granulosus usually involves livestock and dogs; alveolar echinococcosis (AE) due to E. multilocularis involves rodents and canines such as foxes and dogs. Human hosts are infected accidentally via hand to mouth and/or foodborne/waterborne pathways. Albania is deemed to be endemic for cystic echinococcosis (CE), but there is a scarcity of data to confirm this. A systematic literature search was performed in PubMed, Google Scholar, and in other medical sources. Because of the scarcity of existing information, data confirming CE cases were reviewed from the medical hospital records of Albania's largest Hospital, the Mother Teresa University Hospital (UHCMT) Tirana, and from a large private laboratory in Tirana (Pegasus laboratory). A total of eight eligible publications on 540 CE patients were found. Three hundred forty seven additional cases hospitalized in UHCMT from 2011 to 2020 were confirmed, as well as 36 laboratory cases and 10 Albanian cases notified in Germany. Taking all cases into account and considering 162 overlapping cases, 771 cases were documented from 2011 to 2020. The only case reported as AE was most likely a multi-organic CE. Surgery was the most frequent therapy approach used (84.7%). Autochthonous human CE seems to be widespread, and transmission is ongoing in Albania. CE patients in Albania undergo surgery more frequently compared with CE cases in other European countries. In order to establish a realistic estimate of prevalence and incidence of CE in Albania, mandatory notification should be reinforced. Stage-specific therapy can be used in CE to reduce therapy cost and diminish mortality by avoiding surgical overtreatment.

Robotic Liver Surgery for Alveolar Echinococcosis: A Single-Centre Experience

Alveolar echinococcosis (AE) is a rare disease caused by Echinococcosis multilocularis, which usually requires multidisciplinary management including surgery as the only curative approach. In recent years, minimally invasive strategies have been increasingly adopted for liver surgery. In particular, robotic surgery enables surgeons to perform even complex liver resections using a minimally invasive approach. However, there are only a few reports on robotic liver surgery for AE. Consecutive patients undergoing robotic liver surgery for AE were analysed based on the prospective database of the Interdisciplinary Robotic Centre of Ulm University Hospital. Between January 2021 and August 2022, a total of 16 patients with AE underwent robotic hepatectomy at our institution. Median age was 55.5 years (23−73), median body mass index (BMI) was 25.8 kg/m2 (20.2−36.8) and 12 patients (75%) were female. Anatomic resections were performed in 14 patients (87.5%), of which 4 patients (25%) underwent major hepatectomies (i.e., resection of >3 segments) including two right hemihepatectomies, one left hemihepatectomy and one extended right hemihepatectomy performed as associating liver partition with portal vein ligation staged (ALPPS) hepatectomy. There was no 90-day mortality, no postoperative bile leakage and no posthepatectomy haemorrhage. One patient developed posthepatectomy liver failure grade B after extended right hemihepatectomy using an ALPPS approach. One patient had to be converted to open surgery and developed an organ-space surgical site infection, for which he was re-admitted and underwent intravenous antibiotic therapy. Median length of postoperative hospital stay was 7 days (4−30). To our knowledge, this is the largest series of robotic liver surgeries for AE. The robotic approach seems safe with promising short-term outcomes in this selected cohort for both minor as well as major resections.

Expression profiling of Echinococcus multilocularis miRNAs throughout metacestode development in vitro

The neglected zoonotic disease alveolar echinococcosis (AE) is caused by the metacestode stage of the tapeworm parasite Echinococcus multilocularis. MicroRNAs (miRNAs) are small non-coding RNAs with a major role in regulating gene expression in key biological processes. We analyzed the expression profile of E. multilocularis miRNAs throughout metacestode development in vitro, determined the spatial expression of miR-71 in metacestodes cultured in vitro and predicted miRNA targets. Small cDNA libraries from different samples of E. multilocularis were sequenced. We confirmed the expression of 37 miRNAs in E. multilocularis being some of them absent in the host, such as miR-71. We found a few miRNAs highly expressed in all life cycle stages and conditions analyzed, whereas most miRNAs showed very low expression. The most expressed miRNAs were miR-71, miR-9, let-7, miR-10, miR-4989 and miR-1. The high expression of these miRNAs was conserved in other tapeworms, suggesting essential roles in development, survival, or host-parasite interaction. We found highly regulated miRNAs during the different transitions or cultured conditions analyzed, which might suggest a role in the regulation of developmental timing, host-parasite interaction, and/or in maintaining the unique developmental features of each developmental stage or condition. We determined that miR-71 is expressed in germinative cells and in other cell types of the germinal layer in E. multilocularis metacestodes cultured in vitro. MiRNA target prediction of the most highly expressed miRNAs and in silico functional analysis suggested conserved and essential roles for these miRNAs in parasite biology. We found relevant targets potentially involved in development, cell growth and death, lifespan regulation, transcription, signal transduction and cell motility. The evolutionary conservation and expression analyses of E. multilocularis miRNAs throughout metacestode development along with the in silico functional analyses of their predicted targets might help to identify selective therapeutic targets for treatment and control of AE.

Alveolar echinococcosis (AE) is a zoonotic disease caused by the metacestode stage of the helminth parasite Echinococcus multilocularis. Current treatment requires surgery and/or prolonged drug therapy. Thus, novel strategies for the treatment of AE are needed. MicroRNAs (miRNAs), a class of small ~22-nucleotide (nt) non-coding RNAs with a major role in regulating gene expression, have been suggested as potential therapeutic targets for treatment and control of helminth parasite infections. In this work, we analyzed the expression profile of E. multilocularis miRNAs throughout metacestode development in vitro. We predicted functional roles for highly expressed miRNAs and found that they could be involved in essential roles for survival and development in the host. We determined that E. multilocularis miR-71, a highly expressed miRNA that is absent in the human host, is expressed in germinative cells and in other cell types of the germinal layer in E. multilocularis metacestodes cultured in vitro. Germinative cells are a relevant cell type to target for anti-echinococcosis drug development. MiRNAs that are absent in the human host, involved in essential functions, highly expressed and/or expressed in germinative cells in E. multilocularis metacestodes may represent selective therapeutic targets for treatment and control of AE.

Subcutaneous Hydatid Cyst in Laboratory Mice: Is it a Suitable Method for Evaluating Therapeutic Agents against Hydatid Cyst?

Hydatid disease is an economic and public health concern in many countries. Currently, surgery is the main treatment option for hydatid disease. In the surgical treatment of hydatidosis, the use of scolicidal agents is very important due to inactivating live protoscoleces and preventing the recurrence of infection. Therefore, it is necessary to investigate newscolicidal agents and novel medications with higher safety and efficacy. In the previous in vitro studies, the scolicidal effects of the methanolic extracts and aromatic water of Zataria multiflora (Z. multiflora) have been demonstrated. Consequently, in this study, the impact of the nanoemulsion of Z. multiflora essential oil on subcutaneous hydatid cysts was compared with albendazole (ABZ). Fifty laboratory male mice were inoculated with 300 viable protoscoleces subcutaneously on the two sides of the abdomen. Following five months of infection, the remaining infected mice (n=42) were allocated into two treatment and one control (without treatment) groups containing fourteen animals each. Group A received ABZ at the dose of 50 mg/kg for 60 days, group B received the nanoemulsions of Z. multiflora at the dose of 50 mg/kg in drinking water for 60 days, and group C was considered as the control group. All the infected mice were euthanized and necropsied two months post-intervention. Afterwards, the cysts were cautiously collected and their number, size, and weight were compared between the mice of different groups. The mean number of hydatid cysts indicated that the nanoemulsion of Z. multiflora essence had a relative superiority to ABZ. On the other hand, the therapeutic effect of ABZ was higher than the nanoemulsion of Z. multiflora essential oil in terms of the mean weight and mean size of hydatid cysts. However, no significant difference was observed between the groups (P>0.5). Overall, the number, weight, and size of cysts were not significantly different between the groups in this investigation. The lack of satisfactory therapeutic results in this study might be due to the location of hydatid cysts in the subcutaneous space.

Comparative Morphologic and Morphometric Study on the Developmental Aspects of In Vitro and In Vivo Reared Echinococcus granulosus Sensu Stricto Using Differential Interference Contrast (DIC)/Nomarski and Phase Contrast Microscopy

BACKGROUND

Echinococcus granulosus is a zoonotic parasite with worldwide distribution. The present study focused on comparative morphologic and morphometric observations on the developmental aspects of whole body, more special the reproductive structures of in vitro reared adult worms (RAW) and in vivo reared adult worms in definitive host (AWIDH) using differential interference contrast (DIC)/Nomarski, phase contrast and routine optical microscopy.

METHODS

A total number of 10 in vitro and 10 in vivo reared adult worms of E. granulosus sensu stricto, G1 strain were selected. The worms were processed by Formaldehyde-Alcohol-Azocarmine-Lactophenol (FAAL). The details of morphological factors and reproductive structures of each worm including 25 biometrical parameters were studied by routine optical, phase contrast and Nomarski microscopy. The details of the samples were photographed, measured and analyzed. The fine structures of the parasite including the details of cirrus sac and developmental stages in different strobila were more obvious observing by Nomarski microscopy.

RESULTS

The morphometric characters in the RAW and AWIDH showed that length of immature proglottid, length of mature proglottid, length of suckers are larger in RAW than AWIDH worms with statistical difference. Characters in E. granulosus of RAW and AWIDH showed that total number of segments, number of mature segments and the total number of testes were greater in RAW than AWIDH worms; while only the number of mature segments was statistically different is two groups.

CONCLUSION

Application of DIC/Nomarski and phase contrast microscopy together with morphometric criteria are useful means for comparing the developmental aspects of in vitro and in vivo reared adults of E. granulosus.