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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.

What is this article about? Coloring parasites during fecal exams has been widely used to find parasites in human feces. We searched for articles that could help us to answer the question: 'How do dyes give color to parasites?'. Then, we filtered the information from a total of 1334 articles to 35.What were the results? Cryptosporidium spp. and Microsporidia are microbes that can be seen only through a microscope. Researchers were interested in these two species in the last 40 years. Differentiating parasites from dirt on a glass slide is the main problem researchers are trying to solve. The way the light goes through parasites under a microscope, variation of staining, size and temperature of dyes have been explored to identify what gives better results in coloring protocols.What do the results of the study mean? Little is known about the chemical interaction between dyes and parasites. On the other hand, there are many studies on how good coloring methods are and comparing protocols. An alternative to the conventional approaches in staining parasites is the use of computational tools to reduce doubt in the exam interpretation by technicians.

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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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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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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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Because canine intestinal parasites are considered cosmopolitan, they carry significant zoonotic potential to public health. These etiological agents are routinely diagnosed using microscopic examination commonly used because of its low cost, simple execution, and direct evidence. However, there are reports in the literature on the poor performance of this test due to low to moderate sensitivity resulting from frequent errors, procedures and interpretation. Therefore, to improve the diagnostic efficiency of microscopic examination in veterinary medicine, we developed and evaluated a unique new protocol. This system was tested in a study involving four genera of highly prevalent canine intestinal parasites in an endemic region in São Paulo state, Brazil. Fecal samples from 104 animals were collected for this research. The new protocol had a significantly higher (p < 0.0001) number of positive cases on image data, including parasites and impurities, and was elaborate to test them with the TF-GII/Dog technique, with a moderate agreement and Kappa index of 0.7636. We concluded that the new Prototic Coproparasitological Test for Dogs (PC-Test Dog) allowed a better visualization of the parasitic structures and showed a favorable result for the diagnosis of intestinal parasites in dogs.

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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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Acute diarrhea in young dogs is among the main complaints described by tutors in veterinary services. Complications related to water and electrolyte imbalances due to intestinal alterations can compromise homeostasis in these pups, mainly due to dehydration. Consequently, they do not present a satisfactory clinical response and are exposed to the risk of early death. Among the different types of diarrhea, the infectious diarrhea due to viruses, bacteria, and parasites are particularly significant. Coccidia of the genus Isospora (Cystoisospora spp.) is an important intestinal pathogen that causes severe clinical manifestations in puppies. Since high parasitic loads render these puppies highly susceptible to opportunistic infections, coccidia infection may cause impaired corporal and cognitive development and even lead to death. Studies regarding this issue, particularly concerning clinical knowledge in neonatology, are scarce in veterinary medicine. Thus, in this study, we intend to discuss the enteric alterations and the most commonly used current diagnostic techniques, as well as to analyze effective therapeutic and prophylactic proposals.

As diarreias agudas em cães jovens estão entre as principais queixas descritas pelos tutores nos serviços veterinários. As complicações relacionadas aos desequilíbrios hídrico e eletrolítico decorrentes das alterações intestinais comprometem a homeostase destes filhotes, principalmente devido a desidratação, não apresentam resposta clínica satisfatória e ficam expostos ao risco de morte precoce. Dentre os diferentes tipos de diarreia, sobressaem as de origem infecciosa. Os agentes podem ser vírus, bactérias, fungos e parasitos. Entre estes últimos agentes, os coccídios do Gênero Isospora (Cystoisospora spp.) se destacam como patógenos intestinais que ocasionam manifestações clínicas graves em filhotes, pois elevadas cargas parasitárias propiciam condição de maior susceptibilidade à infecções oportunistas, podendo também prejudicar o desenvolvimento corporal e cognitivo e/ou até mesmo levar a morte do cão. Diante de tal temática, na medicina veterinária os estudos são escassos, principalmente quanto ao conhecimento clínico em neonatologia de tal modo tencionamos discutir a respeito das alterações entéricas, métodos de diagnóstico mais utilizados e atuais, bem como analisar as propostas terapêuticas e profiláticas efetivas.

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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.

UTILISATION DU SYSTÈME BIPHASIQUE AQUEUX COMME ALTERNATIVE À LA CONCENTRATION DES ŒUFS D'ASCARIS LUMBRICOIDES, AVEC SÉPARATION NON TOXIQUE DES RÉSIDUS FÉCAUX ET DES GRAISSES: OBJECTIFS: Les entéroparasites humains sont considérés comme un sérieux problème de santé publique dans les pays sous-développés situés dans des régions du monde aux climats tropicaux, subtropicaux et équatoriaux. L'examen parasitologique des matières fécales (EPMF) permet généralement de diagnostiquer ces parasites, à l'aide de techniques classiques et/ou de kits commerciaux, conduisant à des tests de sensibilité faible à modérée, dus à l'utilisation de solvants chimiques destructeurs pour les structures du parasite et résultant en excès de substances adipeuses et de résidus digestifs dans leurs lames microscopiques. Afin d'améliorer l'efficacité de ces tests/examens, cette étude visait à étudier une nouvelle alternative à l'EPMF, avec l'utilisation du Système Biphasique Aqueux (SBA). MÉTHODES: Pour cela, quatre SBA contenant du poly (éthylène glycol), du PEG (PEG-4000 et PEG-6000), du phosphate dipotassique et du citrate de sodium à différentes concentrations ont été évalués avec des échantillons de matières fécales contenant des œufs d'Ascaris lumbricoides. RÉSULTATS: Le SBA constitué de PEG-4000 et de phosphate dipotassique, à des concentrations respectives de 55% poids/poids et 20% poids/poids, a obtenu des résultats satisfaisants à 100% par rapport à la technique conventionnelle du TF-Test, en termes de préservation et de concentration des œufs de A. lumbricoides, avec une séparation adéquate des résidus digestifs, sans utiliser de centrifugeuse ni de solvants chimiques pouvant détruire les parasites. CONCLUSIONS: Cette étude présente le SBA comme un nouveau principe technique peu coûteux pour la détection des œufs de parasites dans l'EPMF. La nouvelle technique est simple, rapide, non toxique, n'endommage pas le parasite et ne nécessite pas de centrifugeuse.

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Acute diarrhea in young dogs is among the main complaints described by tutors in veterinary services. Complications related to water and electrolyte imbalances due to intestinal alterations can compromise homeostasis in these pups, mainly due to dehydration. Consequently, they do not present a satisfactory clinical response and are exposed to the risk of early death. Among the different types of diarrhea, the infectious diarrhea due to viruses, bacteria, and parasites are particularly significant. Coccidia of the genus Isospora (Cystoisospora spp.) is an important intestinal pathogen that causes severe clinical manifestations in puppies. Since high parasitic loads render these puppies highly susceptible to opportunistic infections, coccidia infection may cause impaired corporal and cognitive development and even lead to death. Studies regarding this issue, particularly concerning clinical knowledge in neonatology, are scarce in veterinary medicine. Thus, in this study, we intend to discuss the enteric alterations and the most commonly used current diagnostic techniques, as well as to analyze effective therapeutic and prophylactic proposals.

As diarreias agudas em cães jovens estão entre as principais queixas descritas pelos tutores nos serviços veterinários. As complicações relacionadas aos desequilíbrios hídrico e eletrolítico decorrentes das alterações intestinais comprometem a homeostase destes filhotes, principalmente devido a desidratação, não apresentam resposta clínica satisfatória e ficam expostos ao risco de morte precoce. Dentre os diferentes tipos de diarreia, sobressaem as de origem infecciosa. Os agentes podem ser vírus, bactérias, fungos e parasitos. Entre estes últimos agentes, os coccídios do Gênero Isospora (Cystoisospora spp.) se destacam como patógenos intestinais que ocasionam manifestações clínicas graves em filhotes, pois elevadas cargas parasitárias propiciam condição de maior susceptibilidade à infecções oportunistas, podendo também prejudicar o desenvolvimento corporal e cognitivo e/ou até mesmo levar a morte do cão. Diante de tal temática, na medicina veterinária os estudos são escassos, principalmente quanto ao conhecimento clínico em neonatologia de tal modo tencionamos discutir a respeito das alterações entéricas, métodos de diagnóstico mais utilizados e atuais, bem como analisar as propostas terapêuticas e profiláticas efetivas.

RESUMEN

Acute diarrhea in young dogs is among the main complaints described by tutors in veterinary services. Complications related to water and electrolyte imbalances due to intestinal alterations can compromise homeostasis in these pups, mainly due to dehydration. Consequently, they do not present a satisfactory clinical response and are exposed to the risk of early death. Among the different types of diarrhea, the infectious diarrhea due to viruses, bacteria, and parasites are particularly significant. Coccidia of the genus Isospora (Cystoisospora spp.) is an important intestinal pathogen that causes severe clinical manifestations in puppies. Since high parasitic loads render these puppies highly susceptible to opportunistic infections, coccidia infection may cause impaired corporal and cognitive development and even lead to death. Studies regarding this issue, particularly concerning clinical knowledge in neonatology, are scarce in veterinary medicine. Thus, in this study, we intend to discuss the enteric alterations and the most commonly used current diagnostic techniques, as well as to analyze effective therapeutic and prophylactic proposals.

As diarreias agudas em cães jovens estão entre as principais queixas descritas pelos tutores nos serviços veterinários. As complicações relacionadas aos desequilíbrios hídrico e eletrolítico decorrentes das alterações intestinais comprometem a homeostase destes filhotes, principalmente devido a desidratação, não apresentam resposta clínica satisfatória e ficam expostos ao risco de morte precoce. Dentre os diferentes tipos de diarreia, sobressaem as de origem infecciosa. Os agentes podem ser vírus, bactérias, fungos e parasitos. Entre estes últimos agentes, os coccídios do Gênero Isospora (Cystoisospora spp.) se destacam como patógenos intestinais que ocasionam manifestações clínicas graves em filhotes, pois elevadas cargas parasitárias propiciam condição de maior susceptibilidade à infecções oportunistas, podendo também prejudicar o desenvolvimento corporal e cognitivo e/ou até mesmo levar a morte do cão. Diante de tal temática, na medicina veterinária os estudos são escassos, principalmente quanto ao conhecimento clínico em neonatologia de tal modo tencionamos discutir a respeito das alterações entéricas, métodos de diagnóstico mais utilizados e atuais, bem como analisar as propostas terapêuticas e profiláticas efetivas.

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Sand flies are recognized as the major vector of canine visceral leishmaniasis. However, in some areas of Brazil where sand flies do not occur, this disease is found in humans and dogs. There has been speculation that ticks might play a role in transmission of canine visceral leishmaniasis and the DNA of Leishmania spp. has been reported in whole ticks. We investigated the presence of Leishmania spp. promastigotes in the intestines, ovaries, and salivary glands of Rhipicephalus sanguineus ticks collected from tick-infested dogs in two cities of Brazil. We used 66 dogs that tested positive and 33 that tested negative for Leishmania spp. according to direct cytological examination assays. Ten ticks were collected from each dog and dissected to collect the intestines, ovaries, and salivary glands for immunohistochemistry (IHC) and diagnostic real-time polymerase chain reaction (RT-PCR). IHC results showed Leishmania spp. in 98, 14, and 8 % of the intestines, ovaries, and salivary glands, respectively. Real-time PCR showed that 89, 41, and 33 % of the tick intestine, ovary, and salivary glands, respectively, were positive for Leishmania spp. The verification of promastigotes of Leishmania spp. by two independent techniques in ticks collected from these urban region dogs showed that there is need for clarification of the role of ticks in the transmission of canine visceral leishmaniasis in Brazil.

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Sand flies are recognized as the major vector of canine visceral leishmaniasis. However, in some areas of Brazil where sand flies do not occur, this disease is found in humans and dogs. There has been speculation that ticks might play a role in transmission of canine visceral leishmaniasis and the DNA of Leishmania spp. has been reported in whole ticks. We investigated the presence of Leishmania spp. promastigotes in the intestines, ovaries, and salivary glands of Rhipicephalus sanguineus ticks collected from tick-infested dogs in two cities of Brazil. We used 66 dogs that tested positive and 33 that tested negative for Leishmania spp. according to direct cytological examination assays. Ten ticks were collected from each dog and dissected to collect the intestines, ovaries, and salivary glands for immunohistochemistry (IHC) and diagnostic real-time polymerase chain reaction (RT-PCR). IHC results showed Leishmania spp. in 98, 14, and 8 % of the intestines, ovaries, and salivary glands, respectively. Real-time PCR showed that 89, 41, and 33 % of the tick intestine, ovary, and salivary glands, respectively, were positive for Leishmania spp. The verification of promastigotes of Leishmania spp. by two independent techniques in ticks collected from these urban region dogs showed that there is need for clarification of the role of ticks in the transmission of canine visceral leishmaniasis in Brazil.

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