1
|
Martinez-Hernandez F, Sanchez-Aguillon F, Martinez-Ocaña J, Gonzalez-Arenas NR, Romero-Valdovinos M, Lopez-Escamilla E, Maravilla P, Villalobos G. Genetic Variability of the Internal Transcribed Spacer and Pyruvate:Ferredoxin Oxidoreductase Partial Gene of Trichomonas vaginalis from Female Patients. Microorganisms 2023; 11:2240. [PMID: 37764084 PMCID: PMC10537638 DOI: 10.3390/microorganisms11092240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 08/31/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
In the present study, we evaluated the genetic variability of the internal transcribed spacer (ITS) region and the pyruvate:ferredoxin oxidoreductase (pfor) A gene of Trichomonas vaginalis from female patients and its possible implications in the host-parasite relationship. Phylogenetic and genetics of populations analyses were performed by analyzing sequences of the ITS region and partial pfor A gene of clinical samples with T. vaginalis, as previously documented. Alignments of protein sequences and prediction of three-dimensional structure were also performed. Although no correlation between the main clinical characteristics of the samples and the results of phylogeny was found, a median-joining analysis of ITS haplotypes showed two main clusters. Also, pfor A, due to its phylogenetic divergence, could be used as a marker to confirm the genus and species of trichomonads. Alignment of protein sequences and prediction of three-dimensional structure showed that PFOR A had a highly conserved structure with two synonymous mutations in the PFOR domain, substituting a V for a G or a S for a P. Our results suggest that the role of genetic variability of PFOR and ITS may not be significant in the symptomatology of this pathogen; however, their utility as genus and species markers in trichomonads is promising.
Collapse
Affiliation(s)
- Fernando Martinez-Hernandez
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
| | - Fabiola Sanchez-Aguillon
- Laboratorio de Investigación del Departamento de Biologia Molecular e Histocompatibilidad, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico;
| | - Joel Martinez-Ocaña
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
| | - Nelly Raquel Gonzalez-Arenas
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
| | - Mirza Romero-Valdovinos
- Laboratorio de Patogenos Emergentes, Departamento de Biologia Molecular e Histocompatibilidad, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico;
| | - Eduardo Lopez-Escamilla
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
| | - Pablo Maravilla
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
| | - Guiehdani Villalobos
- Departamento de Ecologia de Agentes Patogenos, Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080, Mexico; (F.M.-H.); (J.M.-O.); (N.R.G.-A.); (E.L.-E.)
- Laboratorio de Biologia Molecular del Departamento de Produccion Agricola y Animal, Universidad Autonoma Metropolitana, Mexico City 04960, Mexico
| |
Collapse
|
2
|
Villalobos G, Sanchez-Aguillon F, Carmona-Maldonado MV, Gonzalez-Arenas NR, Lopez-Escamilla E, Hernandez-Castro R, Romero-Valdovinos M, Martinez-Flores WA, Ramirez-Hinojosa JP, Maravilla P, Martinez-Hernandez F. Unexpected Presence of Blastocystis Subtype 1-3 DNA in Human Vaginal and Sperm Samples Coinfected with Trichomonas vaginalis. Korean J Parasitol 2022; 60:195-200. [PMID: 35772738 PMCID: PMC9256282 DOI: 10.3347/kjp.2022.60.3.195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/12/2022] [Indexed: 11/23/2022]
Abstract
There have been few reports on extra-enteric infections by <i>Blastocystis</i> STs and none have been molecularly identified in samples from human reproductive organs. We report for the first time the identification of 3 different subtypes of <i>Blastocystis</i> (ST1-3) in vaginal and sperm samples, from patients infected with <i>Trichomonas vaginalis</i>. <i>Blastocystis</i> STs were identified by PCR-sequencing and by phylogenetic inferences using 28 vaginal swab samples and 7 sperm samples from patients trichomoniasis. <i>Blastocystis</i> STs were identified in 6 of 28 vaginal swabs (21.4%) and in 3 of 7 sperm samples (42.8%). In both biological samples, STs 1-3 were found; one vaginal sample showed subtype co-infection with ST1 and ST3. High genetic variation was observed in the sequences obtained and no specific clustering in the phylogenetic trees was detected. Most of the haplotypes identified were placed far from the main dispersal centers. Our finding suggested that incorrect cleaning of the genital area or a contamination by combination of anal and vaginal intercourse.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Pablo Maravilla
- Hospital General “Dr. Manuel Gea Gonzalez”, Mexico City 14080,
Mexico
- Corresponding authors (; )
| | | |
Collapse
|
3
|
Martinez-Hernandez F, Martinez-Ibarra JA, Lopez-Escamilla E, Villanueva-Garcia C, Muñoz-Garcia CI, Rendon-Franco E, Maravilla P, Villalobos G. Molecular genotyping of Blastocystis spp. in wild mammals from Mexico. Parasitol Res 2019; 119:97-104. [PMID: 31735993 DOI: 10.1007/s00436-019-06530-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 10/28/2019] [Indexed: 01/26/2023]
Abstract
Blastocystis spp. are common intestinal parasites found worldwide in humans and a wide range of animals. They exhibit extensive genetic diversity; currently, 17 subtypes (STs) and some groups called non-mammalian and avian STs (NMASTs) have been proposed. In addition, a large variety of animals have been reported as hosts of the parasite, and new hosts and STs are still being described. In this study, Blastocystis infection of wild animals in two sylvatic areas of Mexico was surveyed. Of one hundred twenty-four fecal samples, six were positive for Blastocystis: specifically, one sample from an opossum, one sample from a bat, and four samples from different species of rodents. ST4, ST17, and nucleotide sequences similar to Blastocystis lapemi were identified based on SSU rDNA sequences. To our knowledge, this is the first report to investigate species poorly or not previously evaluated for Blastocystis infection. Mammals having different niches and geographical distribution were infected with similar genetic type of Blastocystis, so that we suggest that local water or food sources could play an important role in Blastocystis transmission and ST maintenance in wild animals. Additionally, there are STs with scarce genetic variation, suggesting that they could be highly adapted to their hosts. These data contribute to our understanding of the host range and genetic diversity of Blastocystis.
Collapse
Affiliation(s)
- Fernando Martinez-Hernandez
- Departamento de Ecología de Agentes Patógenos, Hospital General Dr. Manuel Gea González, C.P. 14080, Mexico City, Mexico
| | - Jose Alejandro Martinez-Ibarra
- Laboratorio de Entomología Médica, Centro Universitario del Sur, Universidad de Guadalajara, C.P. 49000, Ciudad Guzmán, Jalisco, Mexico
| | - Eduardo Lopez-Escamilla
- Departamento de Ecología de Agentes Patógenos, Hospital General Dr. Manuel Gea González, C.P. 14080, Mexico City, Mexico
| | - Claudia Villanueva-Garcia
- Laboratorio de Ecología del Paisaje y Cambio Global, Centro de Investigación para la Conservación y Aprovechamiento de Recursos Tropicales, Universidad Juárez Autónoma de Tabasco, C.P. 86150, Villahermosa, Tabasco, Mexico
| | - Claudia Irais Muñoz-Garcia
- Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana, Unidad Xochimilco, C.P. 04960, Mexico City, Mexico
| | - Emilio Rendon-Franco
- Departamento de Producción Agrícola y Animal, Universidad Autónoma Metropolitana, Unidad Xochimilco, C.P. 04960, Mexico City, Mexico
| | - Pablo Maravilla
- Departamento de Ecología de Agentes Patógenos, Hospital General Dr. Manuel Gea González, C.P. 14080, Mexico City, Mexico.
| | - Guiehdani Villalobos
- Departamento de Ecología de Agentes Patógenos, Hospital General Dr. Manuel Gea González, C.P. 14080, Mexico City, Mexico.
| |
Collapse
|
4
|
Alarcon-Valdes P, Villalobos G, Martinez-Flores WA, Lopez-Escamilla E, Gonzalez-Arenas NR, Romero-Valdovinos M, Martinez-Hernandez F, Santillan-Benitez JG, Maravilla P. Can the pyruvate: ferredoxin oxidoreductase (PFOR) gene be used as an additional marker to discriminate among Blastocystis strains or subtypes? Parasit Vectors 2018; 11:564. [PMID: 30373630 PMCID: PMC6205798 DOI: 10.1186/s13071-018-3141-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 10/10/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Blastocystis spp. are the most prevalent intestinal eukaryotes identified in humans, with at least 17 genetic subtypes (ST) based on genes coding for the small-subunit ribosomal RNA (18S). It has been argued that the 18S gene should not be the marker of choice to discriminate between STs of these strains because this marker exhibits high intra-genomic polymorphism. By contrast, pyruvate:ferredoxin oxidoreductase (PFOR) is a relevant enzyme involved in the core energy metabolism of many anaerobic microorganisms such as Blastocystis, which, in other protozoa, shows more polymorphisms than the 18S gene and thus may offer finer discrimination when trying to identify Blastocystis ST. Therefore, the objective of the present study was to assess the suitability of the PFOR gene as an additional marker to discriminate among Blastocystis strains or subtypes from symptomatic carrier children. METHODS Faecal samples from 192 children with gastrointestinal symptoms from the State of Mexico were submitted for coprological study. Twenty-one of these samples were positive only for Blastocystis spp.; these samples were analysed by PCR sequencing of regions of the 18S and PFOR genes. The amplicons were purified and sequenced; afterwards, both markers were assessed for genetic diversity. RESULTS The 18S analysis showed the following frequencies of Blastocystis subtypes: ST3 = 43%; ST1 = 38%; ST2 = 14%; and ST7 = 5%. Additionally, using subtype-specific primer sets, two samples showed mixed Blastocystis ST1 and ST2 infection. For PFOR, Bayesian inference revealed the presence of three clades (I-III); two of them grouped different ST samples, and one grouped six samples of ST3 (III). Nucleotide diversity (π) and haplotype polymorphism (θ) for the 18S analysis were similar for ST1 and ST2 (π = ~0.025 and θ = ~0.036); remarkably, ST3 showed almost 10-fold lower values. For PFOR, a similar trend was found: clade I and II had π = ~0.05 and θ = ~0.05, whereas for clade III, the values were almost 6-fold lower. CONCLUSIONS Although the fragment of the PFOR gene analysed in the present study did not allow discrimination between Blastocystis STs, this marker grouped the samples in three clades with strengthened support, suggesting that PFOR may be under different selective pressures and evolutionary histories than the 18S gene. Interestingly, the ST3 sequences showed lower variability with probable purifying selection in both markers, meaning that evolutionary forces drive differential processes among Blastocystis STs.
Collapse
Affiliation(s)
- Patricia Alarcon-Valdes
- Facultad de Quimica, Universidad Autonoma del Estado de Mexico (UAEMex), Paseo Colon esq. Paseo Tollocan, Toluca, Estado de Mexico, Mexico
| | - Guiehdani Villalobos
- Instituto de Ecologia, Universidad Nacional Autonoma de Mexico (UNAM), 04510, Ciudad de Mexico, Ciudad de Mexico, Mexico
| | | | - Eduardo Lopez-Escamilla
- Hospital General "Dr. Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Ciudad de Mexico, 14080, Ciudad de Mexico, Mexico
| | - Nelly Raquel Gonzalez-Arenas
- Hospital General "Dr. Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Ciudad de Mexico, 14080, Ciudad de Mexico, Mexico
| | - Mirza Romero-Valdovinos
- Hospital General "Dr. Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Ciudad de Mexico, 14080, Ciudad de Mexico, Mexico
| | - Fernando Martinez-Hernandez
- Hospital General "Dr. Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Ciudad de Mexico, 14080, Ciudad de Mexico, Mexico.
| | | | - Pablo Maravilla
- Hospital General "Dr. Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Ciudad de Mexico, 14080, Ciudad de Mexico, Mexico.
| |
Collapse
|
5
|
Villanueva-Garcia C, Gordillo-Chavez EJ, Lopez-Escamilla E, Rendon-Franco E, Muñoz-Garcia CI, Gama L, Martinez-Flores WA, Gonzalez-Rodriguez N, Romero-Valdovinos M, Diaz-Lopez H, Galian J, Villalobos G, Maravilla P, Martinez-Hernandez F. Clarifying the Cryptic Host Specificity of Blastocystis spp. Isolates from Alouatta palliata and A. pigra Howler Monkeys. PLoS One 2017; 12:e0169637. [PMID: 28056072 PMCID: PMC5215913 DOI: 10.1371/journal.pone.0169637] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 12/20/2016] [Indexed: 01/23/2023] Open
Abstract
Although the presence of cryptic host specificity has been documented in Blastocystis, differences in infection rates and high genetic polymorphism within and between populations of some subtypes (ST) have impeded the clarification of the generalist or specialist specificity of this parasite. We assessed the genetic variability and host specificity of Blastocystis spp. in wild howler monkeys from two rainforest areas in the southeastern region of Mexico. Fecal samples of 225 Alouatta palliata (59) and A. pigra (166) monkeys, belonging to 16 sylvatic sites, were analyzed for infection with Blastocystis ST using a region of the small subunit rDNA (SSUrDNA) gene as a marker. Phylogenetic and genetic diversity analyses were performed according to the geographic areas where the monkeys were found. Blastocystis ST2 was the most abundant (91.9%), followed by ST1 and ST8 with 4.6% and 3.5%, respectively; no association between Blastocystis ST and Alouatta species was observed. SSUrDNA sequences in GenBank from human and non-human primates (NHP) were used as ST references and included in population analyses. The haplotype network trees exhibited different distributions: ST1 showed a generalist profile since several haplotypes from different animals were homogeneously distributed with few mutational changes. For ST2, a major dispersion center grouped the Mexican samples, and high mutational differences were observed between NHP. Furthermore, nucleotide and haplotype diversity values, as well as migration and genetic differentiation indexes, showed contrasting values for ST1 and ST2. These data suggest that ST1 populations are only minimally differentiated, while ST2 populations in humans are highly differentiated from those of NHP. The host generalist and specialist specificities exhibited by ST1 and ST2 Blastocystis populations indicate distinct adaptation processes. Because ST1 exhibits a generalist profile, this haplotype can be considered a metapopulation; in contrast, ST2 exists as a set of local populations with preferences for either humans or NHP.
Collapse
Affiliation(s)
- Claudia Villanueva-Garcia
- Departamento de Zoologia y Antropologia Fisica, Facultad de Veterinaria, Universidad de Murcia, Murcia, España
- Departamento de Ecologia del Paisaje y Cambio Global, Centro de Investigacion para la Conservacion y Aprovechamiento de Recursos Tropicales, Universidad Juarez Autonoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Elias Jose Gordillo-Chavez
- Departamento de Ecologia del Paisaje y Cambio Global, Centro de Investigacion para la Conservacion y Aprovechamiento de Recursos Tropicales, Universidad Juarez Autonoma de Tabasco, Villahermosa, Tabasco, Mexico
| | | | - Emilio Rendon-Franco
- Departamento de Produccion Agricola y Animal, Universidad Autonoma Metropolitana, Unidad Xochimilco, Ciudad de Mexico, Mexico
| | - Claudia Irais Muñoz-Garcia
- Departamento de Produccion Agricola y Animal, Universidad Autonoma Metropolitana, Unidad Xochimilco, Ciudad de Mexico, Mexico
| | - Lilia Gama
- Departamento de Ecologia del Paisaje y Cambio Global, Centro de Investigacion para la Conservacion y Aprovechamiento de Recursos Tropicales, Universidad Juarez Autonoma de Tabasco, Villahermosa, Tabasco, Mexico
| | | | | | | | - Hilda Diaz-Lopez
- Departamento de Ecologia del Paisaje y Cambio Global, Centro de Investigacion para la Conservacion y Aprovechamiento de Recursos Tropicales, Universidad Juarez Autonoma de Tabasco, Villahermosa, Tabasco, Mexico
| | - Jose Galian
- Departamento de Zoologia y Antropologia Fisica, Facultad de Veterinaria, Universidad de Murcia, Murcia, España
| | - Guiehdani Villalobos
- Departamento de Ecologia Evolutiva, Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Ciudad de Mexico, Mexico
| | - Pablo Maravilla
- Hospital General “Dr. Manuel Gea Gonzalez”, Secretaria de Salud, Ciudad de Mexico, Mexico
- * E-mail: (PM); (FMH)
| | - Fernando Martinez-Hernandez
- Hospital General “Dr. Manuel Gea Gonzalez”, Secretaria de Salud, Ciudad de Mexico, Mexico
- * E-mail: (PM); (FMH)
| |
Collapse
|
6
|
Villalobos G, Orozco-Mosqueda GE, Lopez-Perez M, Lopez-Escamilla E, Córdoba-Aguilar A, Rangel-Gamboa L, Olivo-Diaz A, Romero-Valdovinos M, Maravilla P, Martinez-Hernandez F. Suitability of internal transcribed spacers (ITS) as markers for the population genetic structure of Blastocystis spp. Parasit Vectors 2014; 7:461. [PMID: 25274498 PMCID: PMC4203911 DOI: 10.1186/s13071-014-0461-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 09/26/2014] [Indexed: 02/04/2023] Open
Abstract
Background The purpose of this study was to assess the genetic variation and differentiation of Blastocystis subtypes (STs) recovered from symptomatic children by analysing partial sequences of the small subunit rDNA gene region (SSUrDNA) and internal transcribed spacers (1 and 2) plus the 5.8S region (ITS, ITS1 + 5.8S + ITS2) and comparing with isolates from other countries. Findings Faecal samples from 47 Blastocystis-infected children with gastrointestinal symptoms and negative for pathogenic enterobacteria were analysed. PCR was performed on DNA from all the samples to identify Blastocystis STs, amplifying a fragment of SSUrDNA and the ITS region. The amplicons were purified and sequenced, and consensus sequences were submitted to GenBank; afterwards, SSUrDNA sequences were analysed for genetic diversity according to geographic area. Regarding the Blastocystis STs found, 51% were ST1, 23% ST2, 19% ST3 and 2% ST7. For ITS, a haplotype network tree and Bayesian inference revealed the presence of two novel variants of ST1, clustering some sequences into ST1A and ST1B. The values of nucleotide diversity (π) and haplotype polymorphism (θ) for ST1, ST2 and ST3 ranged from 0 to 1, whereas the ratio of genetic differentiation (FST)/migration index (Nm) showed the highest differentiation between Libya and Thailand-Philippines for ST2 (0.282/0.63). In contrast, a high flow gene was observed between Czech Republic-Denmark-Holland-Spain and USA-Mexico-Colombia for ST1 (0.003/84). Conclusion Our data on genetic differentiation and gene flow might explain the differences for the prevalence of Blastocystis STs. Moreover, the ITS region could be used as a genetic marker to assess genetic variation in this parasite.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Pablo Maravilla
- Hospital General "Dr, Manuel Gea Gonzalez", Calzada de Tlalpan 4800, Mexico 14080, DF, Mexico.
| | | |
Collapse
|
7
|
Sanchez-Aguillon F, Lopez-Escamilla E, Velez-Perez F, Martinez-Flores WA, Rodriguez-Zulueta P, Martinez-Ocaña J, Martinez-Hernandez F, Romero-Valdovinos M, Maravilla P. Parasitic infections in a Mexican HIV/AIDS cohort. J Infect Dev Ctries 2013; 7:763-6. [PMID: 24129632 DOI: 10.3855/jidc.3512] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 06/12/2013] [Indexed: 10/31/2022] Open
Abstract
This item has no abstract. Follow the links below to access the full text.
Collapse
|
8
|
Ramirez-Miranda ME, Hernandez-Castellanos R, Lopez-Escamilla E, Moncada D, Rodriguez-Magallan A, Pagaza-Melero C, Gonzalez-Angulo A, Flisser A, Kawa-Karasik S, Maravilla P. Parasites in Mexican patients with irritable bowel syndrome: a case-control study. Parasit Vectors 2010; 3:96. [PMID: 20942938 PMCID: PMC2964652 DOI: 10.1186/1756-3305-3-96] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 10/13/2010] [Indexed: 11/10/2022] Open
Abstract
One hundred and fifteen patients with symptoms suggestive of irritable bowel syndrome (IBS) according to Rome III criteria and 209 patients with gastrointestinal symptoms different from IBS (control) were identified through medical records from the Gastroenterology Clinic of the "Dr. Manuel Gea Gonzalez General Hospital" from January 2008 to March 2010. No statistical differences in IBS data as compared with control groups were observed except in bloating, that was more frequent in the IBS group (P = 0.043). Although the pathogenicity of specific intestinal protozoa could not be demonstrated due to lack of association with the development of gastrointestinal symptoms, Blastocystis spp, in the IBS group, exhibited a trend of association to diarrhoea (odds ratio = 2.73, 95% confidence interval = 0.84-8.80, P = 0.053), while having any parasite and diarrhoea was significant (odds ratio = 3.38, 95% confidence interval = 1.33-8.57, P = 0.008). The association between Blastocystis and diarrhoea in IBS patients although not conclusive is an interesting finding; nonetheless more extensive case-controlled studies are required to clearly define the role of some "non-pathogenic" parasites in intestinal disease and IBS.
Collapse
|