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Nery Loiola SH, Stéfano VC, Rosa SL, Proença LR, Dos Santos BM, Soares FA, Saraiva Bresciani KD, Falcão AX, Gomes JF. Staining blindly: an update on coloring techniques for fecal smears in parasitology: a scoping review. Future Microbiol 2024. [PMID: 38530362 DOI: 10.2217/fmb-2023-0171] [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] [Indexed: 03/27/2024] Open
Abstract
Dye application for parasite highlighting in the Ova and Parasite exam is a common practice in parasitology diagnosis. Methods: A scoping review investigated how staining solutions interact with parasite structures. After screening 1334 papers, 35 met eligibility criteria. Results: Differentiating background from foreground in the fecal smear under light microscopy is the core of the research on this topic. Refractivity, unevenness of staining, size and temperature were explored to enhance staining protocols. Cryptosporidium spp. and Microsporidia were the main studied species. Conclusion: Studies on diagnostic efficacy outperform those that elucidate the physical-chemical interaction between dyes and parasites. An alternative approach involves technicians using computational tools to reduce subjectivity in fecal smear interpretation, deviating from conventional methods.
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Affiliation(s)
- Saulo Hudson Nery Loiola
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Vitória Castilho Stéfano
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Stefany Laryssa Rosa
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Letícia Rodrigues Proença
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Bianca Martins Dos Santos
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Felipe Augusto Soares
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
| | - Katia Denise Saraiva Bresciani
- School of Veterinary Medicine, São Paulo State University, Araçatuba, 793, Clóvis Pestana St., Araçatuba - São Paulo, 16050-680, Brazil
| | - Alexandre Xavier Falcão
- Laboratory of Image Data Science, Institute of Computing, University of Campinas, 573, IC-3,5, Saturnino de Brito St., Room 364, Campinas - São Paulo 13083-852, Brazil
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas, 126, Tessália Vieira de Camargo St., Campinas - São Paulo, 13083-887, Brazil
- Laboratory of Image Data Science, Institute of Computing, University of Campinas, 573, IC-3,5, Saturnino de Brito St., Room 364, Campinas - São Paulo 13083-852, Brazil
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Joao LM, Proença LR, Loiola SHN, Inácio SV, Dos Santos BM, Rosa SL, Soares FA, Stefano VC, Osaku D, Suzuki CTN, Bresciani KDS, Gomes JF, Falcão AX. Toward automating the diagnosis of gastrointestinal parasites in cats and dogs. Comput Biol Med 2023; 163:107203. [PMID: 37437360 DOI: 10.1016/j.compbiomed.2023.107203] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/13/2023] [Accepted: 06/25/2023] [Indexed: 07/14/2023]
Abstract
Diagnosing gastrointestinal parasites by microscopy slide examination often leads to human interpretation errors, which may occur due to fatigue, lack of training and infrastructure, presence of artifacts (e.g., various types of cells, algae, yeasts), and other reasons. We have investigated the stages in automating the process to cope with the interpretation errors. This work presents advances in two stages focused on gastrointestinal parasites of cats and dogs: a new parasitological processing technique, named TF-Test VetPet, and a microscopy image analysis pipeline based on deep learning methods. TF-Test VetPet improves image quality by reducing cluttering (i.e., eliminating artifacts), which favors automated image analysis. The proposed pipeline can identify three species of parasites in cats and five in dogs, distinguishing them from fecal impurities with an average accuracy of 98,6%. We also make available the two datasets with images of parasites of dogs and cats, which were obtained by processing fecal smears with temporary staining using TF-Test VetPet.
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Affiliation(s)
- L M Joao
- Institute of Computing, State University of Campinas, R. Saturnino de Brito, Campinas, 13083-852, São Paulo, Brazil.
| | - Letícia Rodrigues Proença
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Saulo Hudson Nery Loiola
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Sandra Valéria Inácio
- School of Veterinary Medicine, São Paulo State University (UNESP), R. Clóvis Pestana, Araçatuba, 16050-680, São Paulo, Brazil.
| | - Bianca Martins Dos Santos
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Stefany Laryssa Rosa
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Felipe Augusto Soares
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Vitória Castilho Stefano
- Institute of Computing, State University of Campinas, R. Saturnino de Brito, Campinas, 13083-852, São Paulo, Brazil.
| | - Daniel Osaku
- Institute of Computing, State University of Campinas, R. Saturnino de Brito, Campinas, 13083-852, São Paulo, Brazil.
| | - Celso Tetsuo Nagase Suzuki
- Institute of Computing, State University of Campinas, R. Saturnino de Brito, Campinas, 13083-852, São Paulo, Brazil.
| | - Katia Denise Saraiva Bresciani
- School of Veterinary Medicine, São Paulo State University (UNESP), R. Clóvis Pestana, Araçatuba, 16050-680, São Paulo, Brazil.
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, State University of Campinas, R. Tessália Vieira de Camargo, Campinas, 13083-887, São Paulo, Brazil.
| | - Alexandre Xavier Falcão
- Institute of Computing, State University of Campinas, R. Saturnino de Brito, Campinas, 13083-852, São Paulo, Brazil.
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Inácio SV, Gomes JF, Falcão AX, Da Silva DRR, Nagata WB, Dos Santos BM, Soares FA, Nery Loiola SH, Benitez ADN, Rosa SL, Bresciani KDS. TF-Test techniques for the laboratory diagnosis of gastrointestinal parasites of humans and animals. Vet Ital 2022; 58. [PMID: 36586119 DOI: 10.12834/vetit.2040.10928.1] [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] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Accepted: 01/18/2020] [Indexed: 01/01/2023]
Abstract
Intestinal parasites inhabit the intestinal tract of humans and animals, causing damages whose severity depends on several factors related to the parasite and the host. Immunocompromised individuals are more likely to develop severe forms of parasitic infestation. The diagnosis of the gastrointestinal parasitosis is mainly performed by the examination of the feces, which consists of the direct visualization and identification of the parasites eliminated through the feces. These tests are generally low sensitive and the microscope slides contain a large number of impurities, which can impair the result of the diagnosis. In order to improve the diagnostic accuracy, a new parasitological technique called Three Fecal Test (TF‑Test) was developed. To further improve its diagnostic accuracy, few modifications of the original protocols have been made with the years. In this study the performance of these new techniques to detect gastrointestinal parasites in human and animal fecal samples was described and discussed in
relation to the performance of other conventional coprological tests. It could be concluded that the TF‑Test conventional and modified can be used for the diagnosis of several human and animal parasites, with satisfactory results.
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Affiliation(s)
- Sandra Valéria Inácio
- Universidade Estadual Paulista (Unesp), Faculdade de Medicina Veterinária, Araçatuba
| | - Jancarlo Ferreira Gomes
- Laboratory of Image Data Science (LIDS) - Instituto de Computação e Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | - Alexandre Xavier Falcão
- Laboratory of Image Data Science (LIDS) - Instituto de Computação e Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | | | | | - Bianca Martins Dos Santos
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | - Felipe Augusto Soares
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | - Saulo Hudson Nery Loiola
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | - Aline do Nascimento Benitez
- Laboratory of Image Data Science (LIDS) - Instituto de Computação e Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
| | - Stefani Laryssa Rosa
- Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brasil
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Soares FA, Dos Santos BM, Rosa SL, Loiola SHN, Stéfano VC, Proença LR, Suzuki CTN, Sabadini E, Bresciani KDS, Falcão AX, Gomes JF. Detection of intestinal parasites in human faecal samples using dissolved air flotation. Trop Med Int Health 2022; 27:1044-1052. [PMID: 36261920 DOI: 10.1111/tmi.13827] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVE Ova and parasite (O&P) examination is recommended for the laboratory diagnosis of agents causing parasitic infections; however, this exam requires scientific and technological improvements to enhance its diagnostic validity. Dissolved air flotation (DAF) is an efficient technical principle separating suspended solids in a liquid medium. We aimed to develop and validate a new procedure for intestinal parasite detection with DAF. METHODS In this study, we collected samples from 500 volunteers, screened them by direct examination, and transferred the material to tubes using the Three Faecal Test (TF-Test) for triplicate DAF tests. We evaluated physical-chemical parameters and DAF prototype components through quantifying parasites recovered from floated and non-floated regions of the flotation column. The DAF operation protocol was validated with the gold standard results. RESULTS The 10% saturated volume proportion and cationic surfactant showed regularity and high parasite recovery (80%). Modifications of the needle device did not influence parasite recovery (p > 0.05). Sensitivity, specificity, accuracy and kappa agreement obtained with the DAF protocol were 91%, 100%, 93% and substantial (k = 0.64), respectively. CONCLUSION The DAF principle could be used to process faecal samples in routine laboratory exams, enabling intestinal parasite detection.
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Affiliation(s)
- Felipe Augusto Soares
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Bianca Martins Dos Santos
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Stefany Laryssa Rosa
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Saulo Hudson Nery Loiola
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Vitória Castilho Stéfano
- Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Letícia Rodrigues Proença
- Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Celso Tetsuo Nagase Suzuki
- Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil.,ImmunoCamp Science and Technology, Vinhedo, São Paulo, Brazil
| | - Edvaldo Sabadini
- Institute of Chemistry, Department of Physics-Chemistry, University of Campinas, Campinas, São Paulo, Brazil
| | | | - Alexandre Xavier Falcão
- Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing (IC), Laboratory of Image Data Science (LIDS), University of Campinas, Campinas, São Paulo, Brazil
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Soares FA, Martins Dos Santos B, Rosa SL, Loiola SHN, Suzuki CTN, Sabadini E, Bresciani KDS, Falcão AX, Gomes JF. Dissolved air flotation as potential new mechanism for intestinal parasite diagnosis in feces. Acta Trop 2021; 224:106137. [PMID: 34562419 DOI: 10.1016/j.actatropica.2021.106137] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 08/17/2021] [Accepted: 09/15/2021] [Indexed: 01/08/2023]
Abstract
The parasitological examination of feces is recommended for the laboratory diagnosis of intestinal parasites due to its practicality, low-cost, and moderate diagnostic sensitivity. Dissolved Air Flotation (DAF) is an efficient technical principle used in other areas to separate dispersed solids. This study sought the preliminary evaluation of a proof-of-concept prototype as a tool for detecting species of parasites by adjusting DAF. Two DAF prototype units were developed to evaluate microbubbles' generation amidst fecal suspension and parasites' capture. For this evaluation, samples were screened and processed by the TF-Test technique (Control) and simultaneously by DAF device. The dimensional and attachment characteristics in the formation of the microbubbles were evaluated, and the percentage of parasitic recovery in floated and not-floated regions compared by Student's t-test. The second prototype unit proved to be more efficient in forming microbubbles with diameters between 34 and 170µm. The flotation tests showed a recovery of 73.27%, 58.12%, 37.85%, and 91.89% for Ascaris lumbricoides, Hymenolepis diminuta, Giardia duodenalis, and Strongyloides stercoralis, respectively. This study confirmed the selective interaction between microbubbles and parasite eggs and larvae during the flotation process using the DAF principle for the first time through imaging.
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Affiliation(s)
- Felipe Augusto Soares
- School of Medical Sciences, University of Campinas, Campinas, São Paulo 13083-889, Brazil; Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil.
| | - Bianca Martins Dos Santos
- School of Medical Sciences, University of Campinas, Campinas, São Paulo 13083-889, Brazil; Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil
| | - Stefany Laryssa Rosa
- School of Medical Sciences, University of Campinas, Campinas, São Paulo 13083-889, Brazil; Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil
| | - Saulo Hudson Nery Loiola
- School of Medical Sciences, University of Campinas, Campinas, São Paulo 13083-889, Brazil; Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil
| | - Celso Tetsuo Nagase Suzuki
- Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil; ImmunoCamp Science and Technology, Vinhedo, São Paulo, Brazil
| | - Edvaldo Sabadini
- Department of Physical-Chemistry, Institute of Chemistry, University of Campinas, Campinas, São Paulo, Brazil
| | | | - Alexandre Xavier Falcão
- Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas, Campinas, São Paulo 13083-889, Brazil; Laboratory of Image Data Science (LIDS), Institute of Computing (IC), University of Campinas, Campinas, São Paulo, Brazil
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Inácio SV, Gomes JF, Falcão AX, Martins dos Santos B, Soares FA, Nery Loiola SH, Rosa SL, Nagase Suzuki CT, Bresciani KDS. Automated Diagnostics: Advances in the Diagnosis of Intestinal Parasitic Infections in Humans and Animals. Front Vet Sci 2021; 8:715406. [PMID: 34888371 PMCID: PMC8650151 DOI: 10.3389/fvets.2021.715406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 10/19/2021] [Indexed: 11/25/2022] Open
Abstract
The increasingly close proximity between people and animals is of great concern for public health, given the risk of exposure to infectious diseases transmitted through animals, which are carriers of more than 60 zoonotic agents. These diseases, which are included in the list of Neglected Tropical Diseases, cause losses in countries with tropical and subtropical climates, and in regions with temperate climates. Indeed, they affect more than a billion people around the world, a large proportion of which are infected by one or more parasitic helminths, causing annual losses of billions of dollars. Several studies are being conducted in search for differentiated, more sensitive diagnostics with fewer errors. These studies, which involve the automated examination of intestinal parasites, still face challenges that must be overcome in order to ensure the proper identification of parasites. This includes a protocol that allows for elimination of most of the debris in samples, satisfactory staining of parasite structures, and a robust image database. Our objective here is therefore to offer a critical description of the techniques currently in use for the automated diagnosis of intestinal parasites in fecal samples, as well as advances in these techniques.
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Affiliation(s)
- Sandra Valéria Inácio
- São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, Brazil
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Institute of Computing (IC), University of Campinas (UNICAMP), Campinas, Brazil
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Soares FA, Benitez ADN, dos Santos BM, Loiola SHN, Rosa SL, Nagata WB, Inácio SV, Suzuki CTN, Bresciani KDS, Falcão AX, Gomes JF. A historical review of the techniques of recovery of parasites for their detection in human stools. Rev Soc Bras Med Trop 2020; 53:e20190535. [PMID: 32491097 PMCID: PMC7269538 DOI: 10.1590/0037-8682-0535-2019] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 04/30/2020] [Indexed: 11/22/2022] Open
Abstract
Since the early 20th century, the detection of intestinal parasites has improved with the development of several techniques for parasitic structures recovery and identification, which differ in sensitivity, specificity, practicality, cost, and infrastructure demand. This study aims to review, in chronological order, the stool examination techniques and discuss their advantages, limitations, and perspectives, and to provide professionals and specialists in this field with data that lays a foundation for critical analysis on the use of such procedures. The concentration procedures that constitute the main techniques applied in routine research and in parasitological kits are a) spontaneous sedimentation; b) centrifugation-sedimentation with formalin-ethyl acetate; and c) flotation with zinc sulfate solution. While selecting a technique, one should consider the purpose of its application and the technical-operational, biological, and physicochemical factors inherent in the procedures used in stool processing, which may restrict its use. These intrinsic limitations may have undergone procedural changes driven by scientific and technological development and by development of alternative methods, which now contribute to the improvement of diagnostic accuracy.
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Affiliation(s)
- Felipe Augusto Soares
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Campinas, SP, Brasil
| | | | | | | | - Stefany Laryssa Rosa
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Campinas, SP, Brasil
| | - Walter Bertequini Nagata
- Universidade Estadual Paulista, Faculdade de Medicina Veterinária, Departamento de Apoio, Produção e Saúde Animal, Araçatuba, SP, Brasil
| | - Sandra Valéria Inácio
- Universidade Estadual Paulista, Faculdade de Medicina Veterinária, Departamento de Apoio, Produção e Saúde Animal, Araçatuba, SP, Brasil
| | | | - Katia Denise Saraiva Bresciani
- Universidade Estadual Paulista, Faculdade de Medicina Veterinária, Departamento de Apoio, Produção e Saúde Animal, Araçatuba, SP, Brasil
| | | | - Jancarlo Ferreira Gomes
- Universidade Estadual de Campinas, Faculdade de Ciências Médicas, Campinas, SP, Brasil
- Universidade Estadual de Campinas, Instituto de Computação, Campinas, SP, Brasil
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Rosa SL, Dos Santos BM, Soares FA, Loiola SHN, Inácio SV, Suzuki CTN, Sabadini E, Falcão AX, Bresciani KDS, Gomes JF. Use of the aqueous biphasic system as an alternative for concentration of Ascaris lumbricoides eggs, with non-toxic separation of faecal residues and fats. Trop Med Int Health 2019; 24:1320-1329. [PMID: 31505102 DOI: 10.1111/tmi.13308] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Human enteroparasites are considered a serious public health problem in underdeveloped countries located in world regions with tropical, subtropical and equatorial climates. These parasites are commonly diagnosed by the Parasitological Examination of Faeces (PEF), performed by conventional techniques and/or commercial kits that result in tests with low-to-moderate sensitivity, due to the use of destructive chemical solvents to parasite structures, and to present excess adipose substance and digestive residues in their microscopic slides. In order to improve the efficacy of these tests/examinations, this study aimed to investigate a new alternative for the PEF, with the use of Aqueous Biphasic System (ABS). METHODS For this, four ABSs containing poly (ethylene glycol), PEG (PEG-4000 and PEG-6000), dipotassium phosphate and sodium citrate at different concentrations in the biphasic systems were evaluated with faecal samples containing eggs of Ascaris lumbricoides. RESULTS The ABS consisting of PEG-4000 and dipotassium phosphate, at concentrations of 55% w/w and 20% w/w, respectively, achieved 100% satisfactory results compared to the conventional TF-Test technique in terms of preservation and concentration of A. lumbricoides eggs, with adequate separation of digestive residues, without using a centrifuge or chemical solvents that may cause harm to the parasites. CONCLUSIONS This study presents ABS as a new low-cost technical principle for the detection of parasite eggs in PEF. The new technique is simple, fast, non-toxic, not harmful to the parasite and does not require a centrifuge.
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Affiliation(s)
| | | | | | | | - Sandra Valéria Inácio
- School of Veterinary Medicine, São Paulo State University, Araçatuba, São Paulo, Brazil
| | | | - Edvaldo Sabadini
- Institute of Chemistry, University of Campinas, Campinas, São Paulo, Brazil
| | | | | | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas, Campinas, São Paulo, Brazil.,Institute of Computing, University of Campinas, Campinas, São Paulo, Brazil
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