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New Microbes and New Infections Sep 2023(), the most common intestinal protozoal pathogen in affluent countries, causes asymptomatic or symptomatic infections with severity ranging from mild to disabling....
BACKGROUND
(), the most common intestinal protozoal pathogen in affluent countries, causes asymptomatic or symptomatic infections with severity ranging from mild to disabling. Currently, many studies of treatment options only have small sample sizes and report results that are partly contradictory.
METHODS
Investigating data retrieved from Helsinki University Hospital and Helsinki City patient records, we searched for the most effective antiprotozoal in treating infections. To study microbiological clearance of , we collected laboratory results of control samples from patients given one of four commonly used antiprotozoals: doxycycline, metronidazole, paromomycin, or secnidazole. For patients symptomatic prior to antiprotozoal treatment, we also retrieved data on clinical outcomes. Furthermore, we explored factors associated with faecal clearance and clinical cure.
RESULTS
A total of 369 patients (median age 38) and 492 treatment episodes were included. Paromomycin (n = 297) proved effective (clearance rate 83%), showing strong association with faecal clearance (aOR 18.08 [7.24-45.16], p < 0.001). For metronidazole the rate was 42% (n = 84), for secnidazole 37% (n = 79), and doxycycline 22% (n = 32). In pairwise comparisons, paromomycin outdid the three other regimens (p < 0.001, test). Faecal clearance was associated with clinical cure (aOR 5.85 [3.02-11.32], p < 0.001).
CONCLUSIONS
Faecal clearance, strongly associated with clinical cure, is most effectively achieved with a course of paromomycin, followed by metronidazole, secnidazole and doxycycline. Our findings will be useful in devising treatment guidelines for adults with symptomatic infection.
PubMed: 37786407
DOI: 10.1016/j.nmni.2023.101179 -
Parasitology Mar 2024Little is known about the life cycle and mode of transmission of . Recently it was suggested that fecal–oral transmission of cysts may play a role in the transmission...
Little is known about the life cycle and mode of transmission of . Recently it was suggested that fecal–oral transmission of cysts may play a role in the transmission of . In order to establish an infection, is required to remain viable when exposed to the pH of the stomach. In this study, we investigated the ability of cultured trophozoites to withstand the extremes of pH. We provide evidence that trophozoites of are vulnerable to highly acidic conditions. We also investigated further the ultrastructure of cysts obtained from mice and rats by transmission electron microscopy. These studies of cysts showed a clear cyst wall surrounding an encysted parasite. The cyst wall was double layered with an outer fibrillar layer and an inner layer enclosing the parasite. Hydrogenosomes, endoplasmic reticulum and nuclei were present in the cysts. Pelta-axostyle structures, costa and axonemes were identifiable and internal flagellar axonemes were present. This study therefore provides additional novel details and knowledge of the ultrastructure of the cyst stage of .
Topics: Animals; Rats; Mice; Dientamoebiasis; Dientamoeba; Life Cycle Stages; Trophozoites; Endoplasmic Reticulum; Feces; Cysts
PubMed: 38250789
DOI: 10.1017/S0031182024000076 -
Dientamoeba fragilis associated with microbiome diversity changes in acute gastroenteritis patients.Parasitology International Dec 2023This study examined the correlation between intestinal protozoans and the bacterial microbiome in faecal samples collected from 463 patients in New Zealand who were...
This study examined the correlation between intestinal protozoans and the bacterial microbiome in faecal samples collected from 463 patients in New Zealand who were diagnosed with gastroenteritis. In comparison to traditional microscopic diagnosis methods, Multiplexed-tandem PCR proved to be more effective in detecting intestinal parasites. Among the identified protozoans, Blastocystis sp. and Dientamoeba fragilis were the most prevalent. Notably, D. fragilis was significantly associated with an increase in the alpha-diversity of host prokaryotic microbes. Although the exact role of Blastocystis sp. and D. fragilis as the primary cause of gastroenteritis remains debatable, our data indicates a substantial correlation between these protozoans and the prokaryote microbiome of their hosts, particularly when compared to other protists or patients with gastroenteritis but no detectable parasitic cause. These findings underscore the significance of comprehending the contributions of intestinal protozoans, specifically D. fragilis, to the development of gastroenteritis and their potential implications for disease management.
Topics: Animals; Humans; Dientamoeba; Intestinal Diseases, Parasitic; Blastocystis; Gastroenteritis; Parasites; Feces
PubMed: 37482266
DOI: 10.1016/j.parint.2023.102788 -
Parasites & Vectors Nov 2023Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 positively affect the fecal bacteriome in children with celiac disease autoimmunity after 6... (Randomized Controlled Trial)
Randomized Controlled Trial
Effects of Lactiplantibacillus plantarum and Lacticaseibacillus paracasei supplementation on the single-cell fecal parasitome in children with celiac disease autoimmunity: a randomized, double-blind placebo-controlled clinical trial.
BACKGROUND
Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 positively affect the fecal bacteriome in children with celiac disease autoimmunity after 6 months of supplementation. The aim of the present investigation was to study the effects of Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 on the single-cell parasitome, with a primary focus on Blastocystis.
METHODS
Stool samples were collected from 78 Swedish children with celiac disease autoimmunity participating in a randomized, double-blind, placebo-controlled clinical trial to either receive a mixture of supplementation with L. plantarum HEAL9 and L. paracasei 8700:2 (n = 38) or placebo (n = 40). A total of 227 stool samples collected at baseline and after 3 and 6 months of intervention, respectively, were retrospectively analyzed for Blastocystis by quantitative real-time PCR and subtyped by massively parallel amplicon sequencing. Other single-cell parasites were detected by untargeted 18S rDNA amplicon sequencing and verified by real-time PCR. The relation between the parasites and the bacteriome community was characterized by using 16S rDNA profiling of the V3-V4 region.
RESULTS
Three different single-cell protists were identified, of which the highest prevalence was found for Dientamoeba fragilis (23.1%, 18/78 children), followed by Blastocystis (15.4%, 12/78) and Entamoeba spp. (2.6%, 2/78). The quantity of the protists was stable over time and not affected by probiotic intervention (P = 0.14 for Blastocystis, P = 0.10 for D. fragilis). The positivity of the protists was associated with increased bacteriome diversity (measured by multiple indices, P < 0.03). Bacterial composition was influenced by the presence of the protists: positivity of Blastocystis was inversely associated with Akkermansia (at the levels of the genus as well as its family, order, class and phylum); P < 0.002), Faecalibacterium (P = 0.003) and Romboutsia (P = 0.029); positivity of D. fragilis was inversely associated with families Enterobacteriaceae (P = 0.016) and Coriobacteriaceae (P = 0.022) and genera Flavonifractor (P < 0.001), Faecalibacterium (P = 0.009), Lachnoclostridium (P = 0.029), Ruminococcus (P < 0.001) and Granulicatella (P = 0.018).
CONCLUSIONS
The prevalence of single-cell protists is low in children with celiac disease autoimmunity. The colonization was stable regardless of the probiotic intervention and associated with increased diversity of the fecal bacteriome but inversely associated with some beneficial bacteria.
Topics: Humans; Child; Lacticaseibacillus; Lacticaseibacillus paracasei; Autoimmunity; Celiac Disease; Retrospective Studies; Feces; Blastocystis; Bacteria; Probiotics; Double-Blind Method; DNA, Ribosomal
PubMed: 37946274
DOI: 10.1186/s13071-023-06027-1 -
Pathogens (Basel, Switzerland) Jun 2023We aimed to assess the performance of the Novodiag Stool Parasites (NSP) assay in the diagnosis of the most common intestinal protozoan and microsporidia infections.
OBJECTIVES
We aimed to assess the performance of the Novodiag Stool Parasites (NSP) assay in the diagnosis of the most common intestinal protozoan and microsporidia infections.
METHODS
A panel of 167 selected stool samples was retrospectively analysed with the NSP assay and compared to routine microscopy and qPCR methods for the detection of pathogenic protozoa and microsporidia.
RESULTS
Whereas specificity was high for all protozoa and microsporidia, NSP sensitivity was strongly dependent on the comparative method used as reference. When compared to microscopic methods, NSP sensitivity was high (96.7 to 100%) for , and but was lower for (85.2%) and ≤50% for and . In comparison to conventional qPCR, the NSP assay demonstrated lower sensitivity characteristics dependent on parasite loads, reaching 60 to 70% for , , spp. and Sensitivity was 100% for , but none of the five samples containing spp. were detected.
CONCLUSIONS
The overall performance of the NSP assay in the diagnosis of gastrointestinal protozoa and microsporidia seems to be better than or equivalent to that observed with microscopic methods but inferior to that obtainable with classical targeted qPCR.
PubMed: 37513736
DOI: 10.3390/pathogens12070889 -
Microorganisms Oct 2023Indigenous people live in remote areas of Colombia. Multiple infections with bacteria, protozoa and/or helminths are common, as well as colonization in various forms....
Indigenous people live in remote areas of Colombia. Multiple infections with bacteria, protozoa and/or helminths are common, as well as colonization in various forms. This study focused on the question of whether and to what extent various pathogens interact with each other. Therefore, a mathematical approach was retrospectively applied to PCR-based data of 244 stool samples, collected in two datasets. A stable cluster solution of the pathogens assessed was determined, and a unique configuration between / spp./ forming cluster 1 and was verified. A pathogen density-dependent interplay appeared between the / spp./ cluster, and . The applied mathematical approach demonstrated that co-infections with parasites of questionable pathological relevance such as and can be of diagnostic relevance due to their ability to promote or repress other pathogens. With the increasing availability of highly sensitive multiplexed molecular diagnostic approaches even in resource-limited settings, where multiple colonization of infection events with enteric pathogens in parallel are common, the importance of interpreting whole pathogen patterns rather than just individual pathogen detection may become more and more relevant.
PubMed: 38004654
DOI: 10.3390/microorganisms11112642 -
Parasitology International Feb 2024Dientamoeba fragilis (D. fragilis) represents a common protozoan in both high and low income countries. Despite this, epidemiological data on dientamoebiasis are still...
Dientamoeba fragilis (D. fragilis) represents a common protozoan in both high and low income countries. Despite this, epidemiological data on dientamoebiasis are still limited, and it is possible that the actual prevalence rates of D. fragilis have been underestimated due to the challenges in its detection and identification. In the present study, symptomatic patients from Rome (Central Italy) were surveyed for two years to determine D. fragilis percentage of infection and genotypes. Stool samples collection was performed over 864 patients, DNA extracted, and RT-PCR performed by the SeeGene Allplex™ Gastrointestinal Parasite Panel Assays. Seventy-nine resulted positive for D. fragilis (9.1%). Co-infections were detected in 22 isolates: 21 displayed Blastocystis sp. + D. fragilis (27.8%). Based on the sequence of a central fragment of the SSU rRNA gene, only genotype 1 was identified. These findings are among the few available data regarding genetic diversity of D. fragilis in Italy. Large-scale human and animal research are required to enhance our knowledge of prevalence, host range, genetic variability and zoonotic transmission of this little-known intestinal protozoan.
Topics: Animals; Humans; Dientamoeba; Genotype; Intestinal Diseases, Parasitic; Dientamoebiasis; Feces; Italy
PubMed: 37838287
DOI: 10.1016/j.parint.2023.102816 -
Infection & Chemotherapy May 2024Enterocolitis and gastroenteritis remain major health problems, particularly in children living in developing countries. Intestinal protozoa, such as , and are...
BACKGROUND
Enterocolitis and gastroenteritis remain major health problems, particularly in children living in developing countries. Intestinal protozoa, such as , and are frequently associated with these conditions. Amebic colitis can cause serious complications, including fulminant necrotizing colitis, toxic megacolon, extraintestinal amebiasis, and stunting in children. The diagnosis of amoebiasis is challenging, relying on microscopic examination, which cannot distinguish from the nonpathogenic and Therefore, this study aimed to identify intestinal parasites, particularly , their prevalence, and the clinical characteristics of patients admitted for enterocolitis and gastroenteritis at a tertiary-referral hospital.
MATERIAL AND METHODS
A cross-sectional, retrospective study was conducted at a national, tertiary-referral government hospital, in Jakarta. Of the 111 retrieved medical records from hospitalized patients with enterocolitis and gastroenteritis, 54 (48.6%) fecal samples were still available in the laboratory storage and referred to the parasitology laboratory. All fecal samples underwent the following tests: 1) direct stool examination, after staining with 1% Lugol's solution, and using the water-ether concentration method; 2) modified acid-fast staining for coccidian parasites; 3) Jones' culture medium to detect ; 4) copro-antigen assay to detect and and 5) a polymerase chain reaction (PCR) assay to identify . Clinical and demographic data were obtained from the medical records.
RESULTS
Largely, patients (44.1%) were from the cohort of young children ≤5 years old, followed by adults aged 19-60 years old (24.3%). Both cohorts exhibited polyparasitism. Intestinal parasites were detected in 17 out of the 54 samples (31.4%). These included 6 (11.1%), 2 (3.7%),5 (9.2%), 3 (5.5%), 2 (3.7%), and 1 (1.8%) samples that were positive for , , , , and respectively. PCR analysis revealed that 10 samples were positive for infection, eight of which originated from pediatric patients.
CONCLUSION
At a national tertiary-referral hospital in Indonesia, infection was most prevalent among pediatric patients with enterocolitis. and were the two main species identified by PCR. Therefore, PCR assays and fecal occult-blood tests are recommended in cases of enterocolitis and gastroenteritis.
PubMed: 38859717
DOI: 10.3947/ic.2023.0099 -
Frontiers in Veterinary Science 2023Non-human primates (NHPs) living in captive conditions are susceptible to intestinal parasites that can contribute to mortality and morbidity, and cause zoonotic...
Non-human primates (NHPs) living in captive conditions are susceptible to intestinal parasites that can contribute to mortality and morbidity, and cause zoonotic infections. Thus, parasite surveys on NHP populations under human care are relevant as part of the evaluation of NHPs welfare and in the zoonotic disease risk assessment, as well as in the exploration of parasite transmission pathways, according to the One-Health concept. This study aimed to identify intestinal parasites infecting NHPs living in two wildlife recovery centers and in a zoological garden, in Italy. Ninety-three fecal samples from and were collected at Piano dell'Abatino Park (Lazio), and fecal smears and flotation were performed in order to identify parasites according to morphological keys. Additionally, one carcass of from the Bioparco Zoological Garden of Rome (Lazio) and one of from the Center for the Recovery of Exotic and Maremma Wild Animals (Tuscany) were necropsied and intestinal adult nematodes were collected and characterized at morphological and molecular level, using the mitochondrial cox1 and rrnL markers. Protozoans (-like, sp.), chromists ( sp.) and nematodes ( sp., sp., strongyliform larvae and sp.) were found through fecal smears and flotation. The collected adult nematodes from dead NHPs were morphologically identified as whipworms (genus ). Phylogenetic analyses grouped specimens into the complex of species, with specimens from clustering into a host-specific branch, and whipworms from clustering within a clade formed by infecting several primate species, including humans. The results here collected revealed the presence of potentially zoonotic parasites circulating in captive primates in Italy, providing useful information for the formulation of management and care plans for captive NHPs, and for the elaboration of safety measures for visitors and animal keepers.
PubMed: 38264469
DOI: 10.3389/fvets.2023.1270202 -
Pathology Apr 2024The protozoan parasite Dientamoeba fragilis is a frequently isolated stool organism and postulated cause of gastrointestinal symptoms. Peripheral blood eosinophilia has...
The protozoan parasite Dientamoeba fragilis is a frequently isolated stool organism and postulated cause of gastrointestinal symptoms. Peripheral blood eosinophilia has been described. This is the first study amongst the Australasian adult population to assess the relationship between organism detection and eosinophilia. A case-control study took place over 7 years at a single Sydney laboratory site, evaluating patients with D. fragilis identified on stool using real-time PCR with a recent full blood count, to control groups with Giardia spp. and sequential negatives with neither organism. A nested study compared those with microscopic evidence of D. fragilis as a marker of disease burden, to molecular diagnosis alone. Sixty-four D. fragilis, 30 Giardia spp., and 94 sequential controls were enrolled. Only 60.1% of samples were preserved in sodium acetate-acetic acid formalin (SAF) fixative, indication mostly not documented. The major co-organism detected amongst all participants was Blastocystis sp., particularly in the D. fragilis cohort (37.2%). The most common pathogen amongst sequential controls was Campylobacter spp. (7.4%). Patients with D. fragilis were more likely (12.5%) to have a clinically significant eosinophilia (>0.5×10/L) compared to those with Giardia spp. (3.3%) or sequential controls (4.3%) (p=0.03). A significant difference was also noted in the overall median eosinophil count of those with D. fragilis versus all controls (0.2 vs 0.1×10/L, p=0.01); however, this was within the reference interval (where up to >0.5×10/L is accepted in healthy individuals within a typical population). No eosinophil difference was found between those with molecular versus additional microscopic detection of D. fragilis (0.1 vs 0.1×10/L). These results support an association between the identification of clinically significant peripheral blood eosinophilia and D. fragilis presence, which may impact the diagnostic approach to the patient with unexplained eosinophilia. Further prospective trials may help assess any significance further and the implication of co-carriage with other enteric organisms. The importance of clinical indication and need for appropriate fixative media in diagnostic parasitology are also highlighted.
PubMed: 38710610
DOI: 10.1016/j.pathol.2024.01.011