Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 103
1.
J Microbiol Methods ; 222: 106957, 2024 May 20.
Article En | MEDLINE | ID: mdl-38777182

As data accumulate in GenBank, the difficulties of delineating species of Cryptosporidium based on nuclear small subunit ribosomal RNA (ssu rRNA) gene information alone becomes increasingly evident. Here, we summarize currently available evidence suggesting that several ssu rDNA sequences primarily referred to as Cryptosporidium suis (some of them from non-suid hosts) should be considered Cryptosporidium occultus.

2.
Gut Microbes ; 16(1): 2337968, 2024.
Article En | MEDLINE | ID: mdl-38591920

Probiotics have been described to influence host health and prevent the risk of obesity by gut microbiome (GM) modulation. In a randomized double-blinded placebo-controlled feasibility study, we investigated whether Vivomixx® multi-strain probiotics administered to 50 women with obesity during pregnancy altered the GM composition and perinatal health outcomes of their infants up to 9 months after birth. The mothers and infants were followed up with four visits after birth: at 3 d, and at 3, 6, and 9 months after delivery. The infants were monitored by anthropometric measurements, fecal sample analysis, and questionnaires regarding health and diet.The study setup after birth was feasible, and the women and infants were willing to participate in additional study visits and collection of fecal samples during the 9-month follow-up. In total, 47 newborns were included for microbiome analysis.Maternal prenatal Vivomixx® administration did not alter infant GM diversity nor differential abundance, and the probiotic strains were not vertically transferred. However, the infant GM exhibited a decreased prevalence of the obesity-associated genera, Collinsella, in the probiotic group and of the metabolic health-associated Akkermansia in the placebo group, indicating that indirect community-scale effects of Vivomixx® on the GM of the mothers could be transferred to the infant.Moreover, 3 d after birth, the GM of the infant was influenced by mode of delivery and antibiotics administered during birth. Vaginally delivered infants had increased diversity and relative abundance of the metabolic health-associated Bifidobacterium and Bacteroides while having a decreased relative abundance of Enterococcus compared with infants delivered by cesarean section. Maternal antibiotic administration during birth resulted in a decreased relative abundance of Bifidobacteriumin the GM of the infants. In conclusion, this study observed potential effects on obesity-associated infant GM after maternal probiotic supplementation.


Gastrointestinal Microbiome , Probiotics , Female , Humans , Infant , Infant, Newborn , Pregnancy , Cesarean Section , Double-Blind Method , Feces/microbiology , Mothers , Obesity , Probiotics/therapeutic use , Feasibility Studies
3.
Parasite Epidemiol Control ; 24: e00332, 2024 Feb.
Article En | MEDLINE | ID: mdl-38188480

Rodents may serve as reservoirs of zoonotic species of Cryptosporidium; however, data from molecular surveys in support of this hypothesis are still scarce. In this study, we screened faeces and rectal content from murid and cricetid rodents (N = 58) caught around three farms in Zealand, Denmark, for Cryptosporidium spp. by amplicon-based next-generation sequencing (NGS) of ribosomal genes. Selected samples were further examined using nested conventional PCR targeting SSU rRNA, gp60, and actin genes. Cryptosporidium-specific DNA was identified in 40/58 (69%) samples, and in 12 (30%) of the 40 positive animals, mixed cryptosporidial infections were observed. Cryptosporidium ditrichi was the species most commonly identified, found in 28 (48%) of the animals. Cryptosporidium parvum was identified in 4 (7%) of the animals, all of which were co-infected with C. ditrichi. The present study is the first to utilize NGS-based screening for Cryptosporidium species in wild rodents. Moreover, it is the first study to provide molecular data on Cryptosporidium in rodents sampled in Denmark and to detect DNA of C. ditrichi in Mus musculus, Myodes glareolus, and Microtus agrestis. The NGS approach was successfully applied to yield new knowledge, and the results showed that zoonotic species of Cryptosporidium are common in murid and cricetid rodents in Zealand, Denmark.

4.
Eur J Haematol ; 112(5): 776-787, 2024 May.
Article En | MEDLINE | ID: mdl-38226781

BACKGROUND: Essential thrombocythemia (ET), polycythemia vera (PV), and primary myelofibrosis (MF) are myeloproliferative neoplasms (MPN). Inflammation is involved in the initiation, progression, and symptomology of the diseases. The gut microbiota impacts the immune system, infection control, and steady-state hematopoiesis. METHODS: We analyzed the gut microbiota of 227 MPN patients and healthy controls (HCs) using next-generation sequencing. We expanded our previous results in PV and ET patients with additional PV, pre-MF, and MF patients which allowed us to compare MPN patients collectively, MPN sub-diagnoses, and MPN mutations (separately and combined) vs. HCs (N = 42) and compare within MPN sub-diagnoses and MPN mutation. RESULTS: MPN patients had a higher observed richness (median, 245 [range, 49-659]) compared with HCs (191.5 [range, 111-300; p = .003]) and a lower relative abundance of taxa within the Firmicutes phylum; for example, Faecalibacterium (6% vs. 14%, p < .001). The microbiota of CALR-positive patients (N = 30) resembled that of HCs more than that of patients with JAK2V617F (N = 177). In JAK2V617F-positive patients, only minor differences in the gut microbiota were observed between MPN sub-diagnoses, illustrating the importance of this mutation. CONCLUSION: The gut microbiota in MPN patients differs from HCs and is driven by JAK2V617F, whereas the gut microbiota in CALR patients resembles HCs more.


Gastrointestinal Microbiome , Myeloproliferative Disorders , Polycythemia Vera , Thrombocythemia, Essential , Humans , Calreticulin/genetics , Janus Kinase 2/genetics , Myeloproliferative Disorders/etiology , Myeloproliferative Disorders/genetics , Polycythemia Vera/genetics , Mutation , Thrombocythemia, Essential/genetics
5.
Emerg Microbes Infect ; 12(2): 2270077, 2023 Dec.
Article En | MEDLINE | ID: mdl-37815802

Giardia intestinalis, a cosmopolitan gastrointestinal protist, is detected mainly in patients with clinical giardiasis in high-income countries. In contrast, there is very little information on the presence of Giardia in asymptomatic individuals. Therefore, the aim of this study was to determine the presence and prevalence of Giardia in gut-healthy volunteers in the Czech Republic and to perform a comparative evaluation of different diagnostic methods, since Giardia diagnostics is complicated. Our results confirmed that the qPCR method is the most sensitive method for detecting Giardia and revealed a prevalence of 7% (22/296) in asymptomatic individuals. In most cases, the colonization intensity ranged from 10-1-101. A conventional PCR protocol targeting the TPI gene was used to identify the assemblages. However, this protocol had limited sensitivity for Giardia amplification, effectively detecting colonization above an intensity of 104. In addition, Giardia was detected in 19% of the animals, which were closely associated with the study participants. However, due to methodological limitations, zoonotic transmission could not be clearly confirmed. Notably, contact with animals proved to be the only factor that had a significant impact on the incidence of Giardia in gut-healthy humans.


Giardia lamblia , Giardiasis , Animals , Humans , Giardia lamblia/genetics , Giardiasis/epidemiology , Giardiasis/diagnosis , Polymerase Chain Reaction , Prevalence , Feces , Genotype
6.
Microbiol Spectr ; : e0066223, 2023 Sep 11.
Article En | MEDLINE | ID: mdl-37695126

Essential thrombocythemia (ET) is part of the Philadelphia chromosome-negative myeloproliferative neoplasms. It is characterized by an increased risk of thromboembolic events and also to a certain degree hypermetabolic symptoms. The gut microbiota is an important initiator of hematopoiesis and regulation of the immune system, but in patients with ET, where inflammation is a hallmark of the disease, it is vastly unexplored. In this study, we compared the gut microbiota via amplicon-based 16S rRNA gene sequencing of the V3-V4 region in 54 patients with ET according to mutation status Janus-kinase 2 (JAK2V617F)-positive vs JAK2V617F-negative patients with ET, and in 42 healthy controls (HCs). Gut microbiota richness was higher in patients with ET (median-observed richness, 283.5; range, 75-535) compared with HCs (median-observed richness, 191.5; range, 111-300; P < 0.001). Patients with ET had a different overall bacterial composition (beta diversity) than HCs (analysis of similarities [ANOSIM]; R = 0.063, P = 0.004). Patients with ET had a significantly lower relative abundance of taxa within the Firmicutes phylum compared with HCs (51% vs 59%, P = 0.03), and within that phylum, patients with ET also had a lower relative abundance of the genus Faecalibacterium (8% vs 15%, P < 0.001), an important immunoregulative bacterium. The microbiota signatures were more pronounced in patients harboring the JAK2V617F mutation, and highly similar to patients with polycythemia vera as previously described. These findings suggest that patients with ET may have an altered immune regulation; however, whether this dysregulation is induced in part by, or is itself inducing, an altered gut microbiota remains to be investigated. IMPORTANCE Essential thrombocythemia (ET) is a cancer characterized by thrombocyte overproduction. Inflammation has been shown to be vital in both the initiation and progression of other myeloproliferative neoplasms, and it is well known that the gut microbiota is important in the regulation of our immune system. However, the gut microbiota of patients with ET remains uninvestigated. In this study, we characterized the gut microbiota of patients with ET compared with healthy controls and thereby provide new insights into the field. We show that the gut microbiota of patients with ET differs significantly from that of healthy controls and the patients with ET have a lower relative abundance of important immunoregulative bacteria. Furthermore, we demonstrate that patients with JAK2V617F-positive ET have pronounced gut microbiota signatures compared with JAK2V617F-negative patients. Thereby confirming the importance of the underlying mutation, the immune response as well as the composition of the microbiota.

7.
IDCases ; 33: e01833, 2023.
Article En | MEDLINE | ID: mdl-37448378

Background: Cystic echinococcosis is non-endemic in Denmark and primarily diagnosed in migrants from endemic areas. Here, we report a case of pulmonary cystic echinococcosis in a Danish woman with no history of longer-term stays abroad, only holiday travelling to tourist destinations. This is the first case reported in international literature from Denmark where the causative parasite was identified to species and genotype level. Case: A 27-year-old pregnant Danish woman was admitted for examination because of haemoptysis for three months.Chest X-ray and computed tomography revealed a cystic structure in the left lung and a left-sided thoracotomy was performed to remove the cyst. Postoperative histopathological examination revealed a hyaline membrane and protoscoleces. Subsequently, infection with Echinococcus granulosus was confirmed by molecular methods. The causative agent was further characterised as E. granulosus sensu stricto G1, which is not known to have an established life cycle in Denmark. It was concluded that the infection was most likely acquired during a tourist travel to an endemic country. The patient was treated with albendazole for four weeks. Conclusion: This case of pulmonary cystic echinococcosis in a person who had lived in Denmark and had history of only short-term tourist travelling abroad highlights that the disease may be acquired during tourist travelling. Thus, a diagnosis of cystic echinococcosis should be considered not only in migrants from endemic countries but also in travellers upon incidental findings of a lung or liver cysts. The case also exemplifies the importance of reaching a diagnosis at species and genotype level.

8.
Res Vet Sci ; 162: 104939, 2023 Sep.
Article En | MEDLINE | ID: mdl-37453229

Blastocystis is a parasitic protist of a variety of hosts, including humans. Mapping the distribution of Blastocystis and its genetic variants across different host species can help us understand the epidemiology of this organism and its role in health and disease. This study aimed to identify subtypes of Blastocystis detected in different animal hosts in Thailand. A total of 825 fecal samples belonging to 18 vertebrate orders, 36 families, 68 genera, and 80 species were collected. Of these, 111 specimens were Blastocystis-positive by culture. Seventy-nine samples were subjected to small subunit (SSU) ribosomal DNA amplification by PCR, and reliable subtype data were obtained for 61 specimens. At least 14 subtypes (ST), namely ST1 to ST10, ST14/ST24/ST25 complex, ST23, ST26, and ST29 were detected. In addition, Blastocystis was found in tortoises. ST1 (3.2%) and ST5 (11.5%) were found in pigs, ST2 (1.6%) and ST3 (3.2%) in non-human primates, ST4 (14.7%) in rodents and ruminants, ST6 (4.9%), ST7 (30%), ST9 (1.6%), and ST29 (1.6%) in birds, ST8 (6.6%) in Green peafowl and East Asian Porcupine, and ST10 (4.9%), ST14/ST24/ST25 (9.8%), ST23 (1.6%) and ST26 (1.6%) in ruminants. The sequence recovered from the elongated tortoises (Indotestudo elongata) (3.2%) was phylogenetically placed within the reptilian cluster of Blastocystis, for which no subtype system is available yet. Of note, we did not obtain Blastocystis sequences from any of the many canids and felids sampled in the study, and our data are in support of host specificity of Blastocystis, according to both colonization and subtype distribution.


Blastocystis Infections , Blastocystis , Animals , Blastocystis/classification , Blastocystis/genetics , Blastocystis/isolation & purification , Blastocystis Infections/epidemiology , Blastocystis Infections/parasitology , Host Specificity , Thailand/epidemiology , Phylogeny , Prevalence , DNA, Ribosomal/genetics
9.
Scand J Gastroenterol ; 58(11): 1253-1263, 2023.
Article En | MEDLINE | ID: mdl-37337895

BACKGROUND: Inflammatory Bowel Disease (IBD) is a group of chronic idiopathic inflammatory diseases of the gastrointestinal (GI) tract associated with the dysbiosis of gut microbiota. Metabarcoding-based profiling of the gut microbiota of IBD patients is generally based on the stool samples collected from individual patients which rarely represent the mucosa-associated microbiota. The ideal sampling strategy for routine monitoring of the mucosal component of IBD has yet to be determined. METHODS: We hereby compare the microbiota composition of the colonic cleansing fluid (CCF) collected during colonoscopy with stool samples from IBD patients. The relationship between IBD and gut microbiota was revealed through the application of the 16S rRNA amplicon sequencing-based metabarcoding approach. CCF and stool samples were collected from IBD patients with Crohn's disease and ulcerative colitis. RESULTS: The present study shows significant differences in the microbial composition of CCF samples, presumably indicating changes in the mucosal microbiota of IBD patients as compared to the control group. Short-chain fatty acid-producing bacteria under the family Lachnospiraceae, the actinobacterial genus Bifidobacterium, the proteobacterial Sutterella and Raoultella are found to contribute to the microbial dysbiosis of the mucosal flora in IBD patients. CONCLUSIONS: CCF microbiota has the capacity to distinguish IBD patients from healthy controls and, thus, may constitute an alternative analysis strategy for the early diagnosis and disease progression in IBD biomarker research.


Colitis, Ulcerative , Inflammatory Bowel Diseases , Microbiota , Humans , Dysbiosis/microbiology , RNA, Ribosomal, 16S/genetics , Inflammatory Bowel Diseases/complications , Microbiota/genetics , Colitis, Ulcerative/complications , Intestinal Mucosa/microbiology , Bacteria/genetics
10.
Int J Parasitol ; 53(11-12): 673-685, 2023 10.
Article En | MEDLINE | ID: mdl-37355198

Molecular characterisation of endobionts that are shared among human and non-human hosts can help shed light on the epidemiology and inform studies that aim to unravel the role of these organisms in health and disease. Two of the most common of shared endobionts include the single-celled intestinal protists Blastocystis and Entamoeba. Here, we present the first known data on genetic diversity and host specificity of these two genera in Greenland. Faecal DNA samples from 243 muskoxen and 44 sheep were submitted to metabarcoding of nuclear small subunit ribosomal DNA. Entamoeba- and Blastocystis-specific sequences were clustered, and consensus sequences were subjected to taxonomic query. Using MinION-based sequencing, near-complete nuclear small subunit ribosomal DNA sequences were obtained from four faecal samples. Of the 243 muskox samples, 180 (74%) and 19 (8%) were positive for Blastocystis and Entamoeba, respectively. Forty (91%) and six (14%) of the 44 sheep samples were positive for Blastocystis and Entamoeba, respectively. Blastocystis subtypes (ST) 10, 14, 21, 24-26, and a novel subtype (ST40) were identified. Colonisation by more than one subtype was common. ST40 was common in muskoxen but limited to Northeast Greenland. Entamoeba bovis and the E. bovis-associated ribosomal lineages (RL) 1 and 8 were found, and three conditional lineages (CL) 3, 4, and 10 were confirmed; CL10 was promoted to RL12. Several novel lineages were identified, all of which were linked to the E. bovis complex. In conclusion, Blastocystis was far more common than Entamoeba and found in approximately three of every four animals; both can be considered common colonisers of large herbivorous mammals in Greenland. Multiple subtypes/lineages of both genera were commonly observed, some of which were novel, but most of which are seen in many other parts of the world.


Blastocystis Infections , Blastocystis , Entamoeba , Sheep , Animals , Blastocystis/genetics , Blastocystis Infections/epidemiology , Blastocystis Infections/veterinary , Greenland , Phylogeny , Feces , Ruminants , DNA, Ribosomal/genetics , Genetic Variation
11.
J Intern Med ; 293(6): 782-790, 2023 06.
Article En | MEDLINE | ID: mdl-37013266

BACKGROUND: Neoehrlichia mikurensis (N. mikurensis) is a newly discovered tick-borne pathogen that can inflict life-threatening illness in immunocompromised patients. N. mikurensis infection is only detectable by polymerase chain reaction (PCR)-based methodologies. We describe three distinct clinical manifestations of N. mikurensis infection (neoehrlichiosis) in Danish patients receiving B-lymphocyte-depleting therapy, rituximab, for underlying hematological, rheumatological, or neurological disorders. All three patients went through a protracted pre-diagnostic period. METHODS: N. mikurensis DNA was detected and confirmed using two methods. Blood was tested by specific real-time PCR targeting the groEL gene and by 16S and 18S profiling followed by sequencing. Bone marrow was analyzed by 16S and 18S profiling. RESULTS: N. mikurensis was detected in blood samples in all three cases and in bone marrow from one of the three. The severity of the symptoms ranged from prolonged fever lasting more than 6 months to life-threatening hyperinflammation in the form of hemophagocytic lymphohistiocytosis (HLH). Interestingly, all patients presented with splenomegaly and two with hepatomegaly. After starting doxycycline therapy, symptoms were relieved within a few days, and biochemistry and organomegaly quickly normalized. CONCLUSION: We present three Danish patients recognized by the same clinician over a period of 6 months, strongly suggesting that many cases are going unrecognized. Second, we describe the first case of N. mikurensis-induced HLH and emphasize the potential severity of undetected neoehrlichiosis.


Anaplasmataceae Infections , Anaplasmataceae , Tick-Borne Diseases , Humans , Anaplasmataceae Infections/diagnosis , Anaplasmataceae Infections/drug therapy , Anaplasmataceae/genetics , Tick-Borne Diseases/diagnosis , Tick-Borne Diseases/drug therapy , Real-Time Polymerase Chain Reaction , Immunocompromised Host
12.
Int J Parasitol Parasites Wildl ; 21: 17-21, 2023 Aug.
Article En | MEDLINE | ID: mdl-37025621

The mountain hares (Lepus timidus L., 1758) in the Faroe Islands, an archipelago located in the North Atlantic, are known to be commonly infected by tapeworms, the identity of which was unknown. The mountain hare, which now populates 15 of the 18 islands, was introduced from Norway in 1855. In this study, tapeworms collected from four mountain hares from four geographic areas of the Faroe Islands were subjected to molecular identification using the nuclear ribosomal DNA (28S), the mitochondrial cytochrome oxidase subunit 1 (cox1) and the NADH dehydrogenase subunit 1 (nad1) genes. The results indicate unambiguously that the tapeworms were Mosgovoyia pectinata (Goeze, 1782) (Cestoda: Anoplocephalidae sensu stricto). The phylogenetic position and origin of the Faroese M. pectinata are discussed. Given that the parasite is quite common in Norway, from where the mountain hares were introduced, it is conceivable that co-introduction of M. pectinata from Norway to the Faroe Islands took place. The phylogenetic analyses revealed high similarity of the M. pectinata sequences from three regions and the position of the Faroese isolate as the sister lineage of the isolates from Finland and East Siberia.

14.
Blood Adv ; 7(13): 3326-3337, 2023 07 11.
Article En | MEDLINE | ID: mdl-36260736

Chronic inflammation is believed to play an important role in the development and disease progression of polycythemia vera (PV). Because an association between gut microbiota, hematopoiesis, and inflammation is well established, we hypothesized that patients with PV have a gut microbiota distinct from healthy control participants (HCs). Recombinant interferon alfa 2 (IFN-α2)-treatment of patients with PV is reportedly disease modifying in terms of normalization of elevated blood cell counts in concert with a reduction in the JAK2V617F allelic burden. Therefore, we hypothesized that patients treated with IFN-α2 might have a composition of the gut microbiota toward normalization. Herein, via amplicon-based next-generation sequencing of the V3 to V4 regions of the 16S ribosomal RNA gene, we report on an abnormal gut microbiota in 102 patients with PV compared with 42 HCs. Patients with PV had a lower alpha diversity and a lower relative abundance of several taxa belonging to Firmicutes (45%) compared with HCs (59%, P <.001). Furthermore, we report the composition of the gut microbiota to differ between the treatment groups (IFN-α2, hydroxyurea, no treatment, and combination therapy with IFN-α2 and ruxolitinib) and the HCs. These observations are highly interesting considering the potential pathogenetic importance of an altered gut microbiota for development of other diseases, including chronic inflammatory diseases. Our observations call for further gut microbiota studies to decipher potential causal associations between treatment and the gut microbiota in PV and related neoplasms.


Gastrointestinal Microbiome , Polycythemia Vera , Humans , Polycythemia Vera/drug therapy , Polycythemia Vera/genetics , Interferon-alpha/therapeutic use , Hydroxyurea , Inflammation
15.
J Eukaryot Microbiol ; 70(2): e12949, 2023 03.
Article En | MEDLINE | ID: mdl-36168968

Despite the species' wide distribution, studies of the genetic diversity within Entamoeba coli and Entamoeba hartmanni remain limited. In the present study, we provide further insight into the genetic diversity of both species based on analysis of partial nuclear small subunit ribosomal DNA sequences generated from human fecal DNAs from samples collected in Africa, South America, and Europe. Reinforcing the previous recognition that E. coli is a species complex, our data confirm the existence of the two subtypes, ST1 and ST2, previously identified plus, potentially, a new subtype, ST3. While ST1 appears to be genetically quite homogenous, ST2 shows a substantial degree of intrasubtype diversity. ST2 was more common in samples collected outside Europe, whereas ST1 showed no geographical restriction. The potentially novel subtype is represented to date exclusively by sequences from South American and African samples. In contrast to previous reports, our new data also indicate substantial variation in E. hartmanni that could also support the establishment of subtypes within this species. Here, however, no links were identified between subtype and geographical origin.


Blastocystis , Entamoeba , Humans , Entamoeba/genetics , Escherichia coli , Interleukin-1 Receptor-Like 1 Protein/genetics , DNA, Ribosomal/genetics , Feces , Phylogeny , Genetic Variation , Blastocystis/genetics
16.
Iran J Parasitol ; 17(3): 296-305, 2022.
Article En | MEDLINE | ID: mdl-36466032

Background: Blastocystis has been associated with various symptoms of the gastrointestinal tract. We aimed to investigate the prevalence of Blastocystis in children with celiac disease (CeD) or functional abdominal pain (FAP) and to evaluate its subtypes (STs) with respect to demographic, socioeconomic and epidemiological factors. Methods: Overall, 161 fecal samples were collected from healthy children and patients with FAP or CeD in Hitit University Erol Olçok Research and Training Hospital, Corum, Turkey between 2016-2018. Samples were examined using both native-Lugol (NL) and trichrome-stained (TS) smears, and further analyses by PCR and Sanger sequencing were performed. A standard questionnaire was applied to obtain demographic, socioeconomic, epidemiological data. Results: Blastocystis was found in 10.6% of the total study population. Neither bacteria nor any other parasites were found, except for one Giardia (0.6%) in the CeD group. The presence/absence of the parasite was not found to be associated with demographic, socioeconomic and epidemiological factors. Blastocysis was detected in 11.5% (6/52) of the CeD, 7.7% (4/52) of the FAP, and 12.3% (7/57) of the healthy group. Diagnostic methods were similar in terms of Blastocystis detection (P= 0.671), and there was fair agreement between the NL, TS and PCR (Fleiss' Kappa=0.847, P=0.001). ST2 (42.8%) and ST3 (35.7%) were the predominant STs followed by ST1 (21.4%). Conclusion: We observed no difference between study groups in terms of Blastocystis prevalence. ST1, ST2 and ST3 subtypes were detected. Blastocystis prevalence and STs were not related to any of the demographic, socioeconomic and epidemiological factors.

17.
Int J Mol Sci ; 23(23)2022 Dec 06.
Article En | MEDLINE | ID: mdl-36499734

Dientamoeba fragilis is a cosmopolitan intestinal protist colonizing the human gut with varying prevalence depending on the cohort studied and the diagnostic methods used. Its role in human health remains unclear mainly due to the very sporadic number of cross-sectional studies in gut-healthy populations. The main objective of this study was to expand knowledge of the epidemiology of D. fragilis in gut-healthy humans and their animals. A total of 296 stool samples from humans and 135 samples from 18 animal species were analyzed. Using qPCR, a prevalence of 24% was found in humans in contrast to conventional PCR (7%). In humans, several factors were found to influence the prevalence of D. fragilis. A more frequent occurrence of D. fragilis was associated with living in a village, traveling outside Europe and contact with farm animals. In addition, co-infection with Blastocystis spp. was observed in nearly half of the colonized humans. In animals, D. fragilis was detected in 13% of samples from eight species using qPCR. Our molecular phylogenies demonstrate a more frequent occurrence of Genotype 1 in gut-healthy humans and also revealed a likely a new protist species/lineage in rabbits related to D. fragilis and other related organisms.


Dientamoebiasis , Animals , Humans , Rabbits , Cross-Sectional Studies , Dientamoebiasis/epidemiology , Dientamoebiasis/diagnosis , Feces , Dientamoeba/genetics , Prevalence
18.
Parasite Epidemiol Control ; 19: e00279, 2022 Nov.
Article En | MEDLINE | ID: mdl-36404991

Severe granulomatous chronic villitis with focal remnants of Toxoplasma was confirmed by immunohistochemistry and DNA-based methods in the placenta from a child that died four days after birth. The immunocompetent mother was seronegative for Toxoplasma at delivery and 10 months later. Placental infection may happen without maternal systemic infection.

19.
Pathogens ; 11(11)2022 Oct 31.
Article En | MEDLINE | ID: mdl-36365028

The enteric protozoan parasites Cryptosporidium spp., Giardia duodenalis and Dientamoeba fragilis are-to various extents-contributors to the burden of gastrointestinal illness in high-income countries. Detection of these pathogens by microscopy examination is challenging because of the limited sensitivity and need for specific staining procedures. We developed and optimised a new multiplex real-time PCR assay for the simultaneous detection of Cryptosporidium spp., G. duodenalis and D. fragilis in clinical (stool) samples. The diagnostic performance of the assay was evaluated against a large panel of well-characterised DNA samples positive for Cryptosporidium spp. (n = 126), G. duodenalis (n = 132) and D. fragilis (n = 49). The specificity of the test was assessed against a DNA panel from other intestinal or phylogenetically related parasites (n = 105) and faecal DNA from individuals without clinical manifestations (n = 12). The assay exhibited a diagnostic sensitivity of 0.90-0.97 and a diagnostic specificity of 1. The limit of detection was estimated for Cryptosporidium (1 oocyst) and G. duodenalis (5 × 10-4 cysts). The method allowed the detection of four Cryptosporidium species (C. hominis, C. parvum, C. meleagridis and C. cuniculus) and five G. duodenalis assemblages (A-E) without cross-reacting with other parasites belonging to the phyla Amoebozoa, Apicomplexa, Euglenozoa, Microsporidia, Nematoda and Platyhelminthes. This newly developed multiplex real-time PCR assay represents a novel alternative for the rapid and accurate detection of Cryptosporidium, G. duodenalis and D. fragilis in clinical settings.

20.
BMJ Case Rep ; 15(9)2022 Sep 22.
Article En | MEDLINE | ID: mdl-36137646

Strongyloidiasis is a disease caused by the intestinal helminth Strongyloides stercoralis When the immune system of infected individuals is compromised, larvae may migrate from the gastrointestinal tract to other tissues, causing S. stercoralis hyperinfection syndrome, which has a reported mortality of 71%. In this case, we report a patient with S. stercoralis hyperinfection syndrome with central nervous system (CNS) involvement. An elderly South East Asian male tourist presented with pulmonary symptoms, fever and infiltrates on chest X-ray. He later developed symptoms of CNS infection. S. stercoralis larvae were found in a stool sample. Microbiological examination of cerebrospinal fluid revealed S. stercoralis-specific DNA. The patient was treated with oral and rectal ivermectin and albendazole. The condition was complicated by sepsis, bacteraemia and hypereosinophilia. Unfortunately, the patient eventually died from pulmonary oedema and insufficiency. This case highlights the global importance of Strongyloides CNS infection in endemic and non-endemic regions.


Eosinophilia , Strongyloides stercoralis , Strongyloidiasis , Aged , Albendazole/therapeutic use , Animals , Eosinophilia/complications , Humans , Ivermectin/therapeutic use , Larva , Male , Strongyloidiasis/complications , Strongyloidiasis/diagnosis , Strongyloidiasis/drug therapy , Syndrome
...