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Kevin R Kazacos - One of the best experts on this subject based on the ideXlab platform.
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Baylisascaris procyonis associated meningoencephalitis in a previously healthy adult california usa
Emerging Infectious Diseases, 2016Co-Authors: Charles Langelier, Michael J A Reid, Cathra Halabi, Natalie Witek, Alejandro Lariviere, Maulik P Shah, Michael R Wilson, Peter Chinhong, Vanja C Douglas, Kevin R KazacosAbstract:After severe neurocognitive decline developed in an otherwise healthy 63-year-old man, brain magnetic resonance imaging showed eosinophilic meningoencephalitis and enhancing lesions. The patient tested positive for antibodies to Baylisascaris spp. roundworms, was treated with albendazole and dexamethasone, and showed improvement after 3 months. Baylisascariasis should be considered for all patients with eosinophilic meningitis.
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case report Baylisascaris procyonis and herpes simplex virus 2 coinfection presenting as ocular larva migrans with granuloma formation in a child
American Journal of Tropical Medicine and Hygiene, 2015Co-Authors: Glenn J Fennelly, Kevin R Kazacos, Christina M. Coyle, Charles Grose, Joanna Dobroszycki, Norman Saffra, Louis M Weiss, Moshe Szlechter, Herbert B. TanowitzAbstract:Abstract. Ocular Baylisascaris procyonis infection results from ingestion of infective eggs of B. procyonis, the raccoon ascarid. Herpes simplex virus type 2 (HSV-2) infection of the retina is the result of either primary infection or reactivated disease. Herein, we report a case of a 12-year-old female resident of the Bronx in New York City, who presented with pan-uveitis and vision loss. Initial evaluation for etiologic causes was nondiagnostic. Serology for anti-Baylisascaris procyonis antibodies in serum and vitreous fluid were both positive. Polymerase chain reaction (PCR) of vitreous fluid was positive for HSV-2. Treatment with vitrectomy, albendazole, and acyclovir resulted in mild improvement of visual acuity. The atypical presentation of B. procyonis in this case, as ocular larva migrans with a peripheral granuloma and retinal detachment, underscores the importance of maintaining a high degree of suspicion for this pathogen even in non-diffuse unilateral subacute neuroretinitis (DUSN) patients in urban areas. This case further illustrates that it is possible to have coexisting infections in cases of posterior uveitis.
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Baylisascaris larva migrans
Handbook of Clinical Neurology, 2013Co-Authors: Kevin R Kazacos, Linda A Jelicks, Herbert B. TanowitzAbstract:: Baylisascaris procyonis is a roundworm of the raccoon found primarily in North America but also known to occur in other parts of the world including South America, Europe, and Japan. Migration of the larvae of this parasite is recognized as a cause of clinical neural larva migrans (NLM) in humans, primarily children. It is manifested as meningoencephalitis associated with marked eosinophilia of the cerebrospinal fluid and peripheral blood. Diagnosis is made by recovering and identifying larvae in or from the tissues, epidemiological history, serology, and imaging of the central nervous system. Treatment is with albendazole and steroids, although the prognosis is generally poor. This parasite can also cause ocular larva migrans (OLM) which usually presents as diffuse unilateral subacute neuroretinitis (DUSN). The ocular diagnosis can be made by visualizing the larva in the eye and by serology. Intraocular larvae can be destroyed by photocoagulation although albendazole and steroids may also be used. However, once visual disturbance is established the prognosis for improved vision is poor. Related Baylisascaris species occur in skunks, badgers, and certain other carnivores, although most cases of NLM are caused by B. procyonis. Baylisascaris procyonis has also been found in kinkajous in the USA and South America and may also occur in related procyonids (coatis, olingos, etc.).
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Spinal cord involvement in a child with raccoon roundworm (Baylisascaris procyonis) meningoencephalitis
Pediatric Radiology, 2012Co-Authors: Teresa G. Kelly, Kevin R Kazacos, Jurriaan M Peters, Vandana L Madhavan, V. Michelle SilveraAbstract:A 14-month-old previously healthy boy developed progressively worsening neurological symptoms secondary to eosinophilic meningoencephalitis with myelitis caused by raccoon roundworm (Baylisascaris procyonis) infection. MRI demonstrated T2 hyperintensity and enhancement of the cerebral white matter, cerebellum and spinal cord. Prior case reports have described signal abnormality within the brains of patients with raccoon roundworm neural larva migrans (NLM). This is a unique case in which spinal cord involvement was established by imaging. Knowledge of this combination of imaging findings expands the known imaging phenotype of this noteworthy infection.
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good outcome with early empiric treatment of neural larva migrans due to Baylisascaris procyonis
Pediatrics, 2012Co-Authors: Jurriaan M Peters, Kevin R Kazacos, Sriveny Dangoudoubiyam, Vandana L Madhavan, Robert N Husson, Janet S SoulAbstract:We report a remarkably good outcome in a 14-month-old boy with early clinical diagnosis and aggressive empirical treatment of neural larva migrans caused by the raccoon roundworm Baylisascaris procyonis . He presented with fever, meningismus, lethargy, irritability and asymmetric spastic extremity weakness. Early findings of marked blood and cerebrospinal fluid eosinophilia and of diffuse white matter signal abnormality in the brain and spinal cord on MRI suggested a parasitic encephalomyelitis. Rapid presumptive treatment with albendazole and high-dose steroids halted progression of clinical signs. The diagnosis was confirmed by 2 sequential enzyme-linked immunosorbent assay studies positive for B procyonis serum immunoglobulin G and by Western blot. Field examination with soil sampling yielded infective Baylisascaris eggs. Repeat MRI 3 months later showed atrophy and diffuse, chronic white matter abnormalities, discordant with the marked clinical improvement in this interval. At 10 months, residual neurologic deficits included subtle paraparesis and moderate language delay. This case is the first in which spinal involvement in human Baylisascaris infection was clinically suspected and confirmed by neuroimaging. Importantly, early diagnosis and aggressive treatment of Baylisascaris meningo-encephalitis and myelitis with albendazole and high-dose steroids likely contributed to the good outcome in this patient, in contrast with previous reports. * Abbreviations: CSF — : cerebrospinal fluid ELISA — : enzyme-linked immunosorbent assay Ig — : immunoglobulin NLM — : neural larva migrans OD — : optical density
Guangyou Yang - One of the best experts on this subject based on the ideXlab platform.
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molecular phylogenetics and species level systematics of Baylisascaris
International journal for parasitology. Parasites and wildlife, 2018Co-Authors: Lauren Camp, Guangyou Yang, Marc R Radke, Danny M Shihabi, Christopher Pagan, Steven A NadlerAbstract:Abstract Nucleotide sequences representing nine genes and five presumptive genetic loci were used to infer phylogenetic relationships among seven Baylisascaris species, including one species with no previously available molecular data. These genes were used to test the species status of B. procyonis and B. columnaris using a coalescent approach. Phylogenetic analysis based on combined analysis of sequence data strongly supported monophyly of the genus and separated the species into two main clades. Clade 1 included B. procyonis, B. columnaris, and B. devosi, species hosted by musteloid carnivores. Clade 2 included B. transfuga and B. schroederi from ursids, B. ailuri, a species from the red panda (a musteloid), and B. tasmaniensis from a marsupial. Within clade 2, geographic isolates of B. transfuga, B. schroederi (from giant panda), and B. ailuri formed a strongly supported clade. In certain analyses (e.g., some single genes), B. tasmaniensis was sister to all other Baylisascaris species rather than sister to the species from ursids and red panda. Using one combination of priors corresponding to moderate population size and shallow genetic divergence, the multispecies coalescent analysis of B. procyonis and B. columnaris yielded moderate support (posterior probability 0.91) for these taxa as separate species. However, other prior combinations yielded weak or no support for delimiting these taxa as separate species. Similarly, tree topologies constrained to represent reciprocal monophyly of B. columnaris and B. procyonis individuals (topologies consistent with separate species) were significantly worse in some cases, but not others, depending on the dataset analyzed. An expanded analysis of SNPs and other genetic markers that were previously suggested to distinguish between individuals of B. procyonis and B. columnaris was made by characterization of additional individual nematodes. The results suggest that many of these SNPs do not represent fixed differences between nematodes derived from raccoon and skunk hosts.
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cloning and characterization of a novel sigma like glutathione s transferase from the giant panda parasitic nematode Baylisascaris schroederi
Parasites & Vectors, 2015Co-Authors: Xuan Zhou, Zhihe Zhang, Chengdong Wang, Xiaobin Gu, Xuerong Peng, Lin Chen, Tao Wang, Guangyou YangAbstract:Background Baylisascaris schroederi, an intestinal nematode of the giant panda, is the cause of the often fatal disease, baylisascariasis. Glutathione S-transferases (GSTs) are versatile enzymes that can affect parasite survival and parasite-host interactions and, are therefore, potential targets for the development of diagnostic tests and vaccines.
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zoonotic Baylisascaris procyonis roundworms in raccoons china
Emerging Infectious Diseases, 2014Co-Authors: Xuan Zhou, Xiaobin Gu, Xuerong Peng, Tao Wang, Mei Li, Guangyou YangAbstract:To the Editor: Baylisascaris procyonis, an intestinal roundworm that infects raccoons (Procyon lotor), causes fatal or severe neural larva migrans in animals and humans (1,2). Globally, ≈130 species of wild and domesticated animals are susceptible (2). Infections in humans typically occur in children who have the disorders pica or geophagia and ingest B. procyonis eggs in items contaminated with raccoon feces (3). Clinical manifestations include ocular disease, eosinophilic encephalitis, and eosinophilic cardiac pseudotumors; severe infection can lead to death. Since 1984, ≈24 cases of B. procyonis–related human neural larva migrans have been reported, mainly in the United States (1,3–5; K.R. Kazacos, pers. comm.). Despite few cases among humans, lack of effective treatment and widespread distribution of infected raccoons in close association with humans make B. procyonis a potentially serious public health threat (2,6). The current distribution of B. procyonis is poorly recorded in Asia (2,7), except for Japan (8). We describe B. procyonis infections among raccoons in China as part of a series of ongoing surveys of helminthic zoonoses linked to captive exotic animals in zoologic gardens (ZGs) in China. More than 90% of raccoons in China (n >320) are raised as exotic ornamental animals in 18 ZGs. During 2011–2013, we collected 2×308 fecal samples (i.e., 1 repeat within each sampling) from 277 raccoons in 12 randomly selected ZGs (Technical Appendix Figure 1). Samples were stored in individual plastic bags at –20°C until use. We examined raccoons (n = 31) at the Sichuan ZGs twice, in June 2012 and May 2013. We identified B. procyonis eggs in feces using morphologic and molecular analyses (1,2,9). The nuclear first internal transcribed spacer (428 bp) and mitochondrial cytochrome c oxidase subunit 1 (cox-1, 938 bp) genes in each sample were PCR-amplified and sequenced. B. procyonis infection was confirmed by sequencing and phylogenetic analyses of both genes (7,9). We reexamined ≈60% of fecal samples to validate results. Prevalence (95% CI) was calculated for the overall population and independently for female, male, juvenile, and adult raccoons. We determined differences between the tested ZG prevalence and prevalence by sex or age of raccoons using χ2 or Fisher exact tests in SAS (SAS Institute, Cary, NC, USA); p values <0.05 were considered significant. Building on egg-based morphologic characterization and internal transcribed spacer 1 and cox-1 gene-based phylogenies using neighbor-joining trees (Technical Appendix Figure 2), we found B. procyonis in raccoon feces from 5/12 ZGs (42%; 95% CI 14%–70%), including 2 in the most densely populated provinces, Henan and Sichuan. More infections were found in western than central and eastern ZGs (4/6 and 1/6, respectively; Table, Technical Appendix Figure 1) (p = 0.079). Fecal samples of 35 raccoons (13%; 95% CI 9%–17%) tested positive for B. procyonis. The mean intensity of egg shedding was 5,000 eggs per gram (range 800–11,200 eggs per gram; data not shown). No significant difference was observed in the intensity of shedding by comparing sex and age of animals, and no significant differences were noted in the mean prevalence between female and male raccoons (12% versus 14%; p = 0.677) or between adult and juvenile animals (13% versus 10%; p = 0.536). Table Prevalence of Baylisascaris procyonis roundworm infections among captive raccoons, China, 2011–2013* This investigation documents the presence and prevalence of B. procyonis among raccoons in China. The findings imply that raccoons harboring this parasite have the potential for spreading it to humans. One reason is that captive raccoons adapt readily to humans and easily take food offered by hand; another is that communal raccoon latrine sites in ZGs are usually close to areas where humans gather, so ZG visitors may be exposed to large numbers of eggs (Technical Appendix Figure 3). These eggs can remain viable and infective for years (2), and latrines are recognized as primary sources of transmission of B. procyonis to humans (4). Current public health initiatives to prevent B. procyonis infections in humans rely on the education of veterinary and human health care professionals, who in turn inform the public (1,6,10). Thus, veterinarians, clinicians, and public health officials in China should be more informed about this pathogen, especially in regions with large raccoon populations. Because of a lack of clinical awareness of this illness and subsequent lack of early diagnosis and effective treatment, prevention of B. procyonis infection by education is essential. In addition, a strategy for eradication is needed. Heat, in the form of boiling water, steam-cleaning, or fire, is the optimal tool for killing B. procyonis eggs (2) and therefore can be used to decontaminate areas surrounding latrines. Within heavily contaminated areas, removing and then sterilizing the top few inches of surface soil with heat would be effective and practical (1,2). Among captive raccoon populations, particularly in China, regular deworming is also likely to be helpful in reducing novel and existing sources of infection (1–3). Finally, although no cases of human infection have been reported in China to our knowledge, physicians should consider including B. procyonis infections in their differential diagnoses of patients with indicative features: clinical (eosinophilic encephalitis, ocular disease), epidemiologic (raccoon exposure), radiologic (white matter disease), and laboratory results (blood and CNS eosinophilia) (1,10). This study lays the foundation for future steps to educate the population of China about B. procyonis infection and to create programs to prevent the spread of this disease to humans. Technical Appendix: Distribution of raccoons in China, morphological and molecular characterization of Baylisascaris procyonis parasitic roundworm eggs in captive raccoons in China, and the potential risk of human B. procyonis infection in China. Click here to view.(776K, pdf)
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Zoonotic Baylisascaris procyonis roundworms in raccoons, China.
Emerging Infectious Diseases, 2014Co-Authors: Xuan Zhou, Xiaobin Gu, Xuerong Peng, Tao Wang, Mei Li, Guangyou YangAbstract:To the Editor: Baylisascaris procyonis, an intestinal roundworm that infects raccoons (Procyon lotor), causes fatal or severe neural larva migrans in animals and humans (1,2). Globally, ≈130 species of wild and domesticated animals are susceptible (2). Infections in humans typically occur in children who have the disorders pica or geophagia and ingest B. procyonis eggs in items contaminated with raccoon feces (3). Clinical manifestations include ocular disease, eosinophilic encephalitis, and eosinophilic cardiac pseudotumors; severe infection can lead to death. Since 1984, ≈24 cases of B. procyonis–related human neural larva migrans have been reported, mainly in the United States (1,3–5; K.R. Kazacos, pers. comm.). Despite few cases among humans, lack of effective treatment and widespread distribution of infected raccoons in close association with humans make B. procyonis a potentially serious public health threat (2,6). The current distribution of B. procyonis is poorly recorded in Asia (2,7), except for Japan (8). We describe B. procyonis infections among raccoons in China as part of a series of ongoing surveys of helminthic zoonoses linked to captive exotic animals in zoologic gardens (ZGs) in China. More than 90% of raccoons in China (n >320) are raised as exotic ornamental animals in 18 ZGs. During 2011–2013, we collected 2×308 fecal samples (i.e., 1 repeat within each sampling) from 277 raccoons in 12 randomly selected ZGs (Technical Appendix Figure 1). Samples were stored in individual plastic bags at –20°C until use. We examined raccoons (n = 31) at the Sichuan ZGs twice, in June 2012 and May 2013. We identified B. procyonis eggs in feces using morphologic and molecular analyses (1,2,9). The nuclear first internal transcribed spacer (428 bp) and mitochondrial cytochrome c oxidase subunit 1 (cox-1, 938 bp) genes in each sample were PCR-amplified and sequenced. B. procyonis infection was confirmed by sequencing and phylogenetic analyses of both genes (7,9). We reexamined ≈60% of fecal samples to validate results. Prevalence (95% CI) was calculated for the overall population and independently for female, male, juvenile, and adult raccoons. We determined differences between the tested ZG prevalence and prevalence by sex or age of raccoons using χ2 or Fisher exact tests in SAS (SAS Institute, Cary, NC, USA); p values
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the mitochondrial genome of Baylisascaris procyonis
PLOS ONE, 2011Co-Authors: Zhihe Zhang, Chengdong Wang, Yan Fu, Xiaobin Gu, Shuxian Wang, Xuerong Peng, Qiang Wang, Jiabo Deng, Deying Yang, Guangyou YangAbstract:Background Baylisascaris procyonis (Nematoda: Ascaridida), an intestinal nematode of raccoons, is emerging as an important helminthic zoonosis due to serious or fatal larval migrans in animals and humans. Despite its significant veterinary and public health impact, the epidemiology, molecular ecology and population genetics of this parasite remain largely unexplored. Mitochondrial (mt) genomes can provide a foundation for investigations in these areas and assist in the diagnosis and control of B. procyonis. In this study, the first complete mt genome sequence of B. procyonis was determined using a polymerase chain reaction (PCR)-based primer-walking strategy. Methodology/Principal Findings The circular mt genome (14781 bp) of B. procyonis contained 12 protein-coding, 22 transfer RNA and 2 ribosomal RNA genes congruent with other chromadorean nematodes. Interestingly, the B. procyonis mtDNA featured an extremely long AT-rich region (1375 bp) and a high number of intergenic spacers (17), making it unique compared with other secernentean nematodes characterized to date. Additionally, the entire genome displayed notable levels of AT skew and GC skew. Based on pairwise comparisons and sliding window analysis of mt genes among the available 11 Ascaridida mtDNAs, new primer pairs were designed to amplify specific short fragments of the genes cytb (548 bp fragment) and rrnL (200 bp fragment) in the B. procyonis mtDNA, and tested as possible alternatives to existing mt molecular beacons for Ascaridida. Finally, phylogenetic analysis of mtDNAs provided novel estimates of the interrelationships of Baylisasaris and Ascaridida. Conclusions/Significance The complete mt genome sequence of B. procyonis sequenced here should contribute to molecular diagnostic methods, epidemiological investigations and ecological studies of B. procyonis and other related ascaridoids. The information will be important in refining the phylogenetic relationships within the order Ascaridida and enriching the resource of markers for systematic, population genetic and evolutionary biological studies of parasitic nematodes of socio-economic importance.
Herbert B. Tanowitz - One of the best experts on this subject based on the ideXlab platform.
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case report Baylisascaris procyonis and herpes simplex virus 2 coinfection presenting as ocular larva migrans with granuloma formation in a child
American Journal of Tropical Medicine and Hygiene, 2015Co-Authors: Glenn J Fennelly, Kevin R Kazacos, Christina M. Coyle, Charles Grose, Joanna Dobroszycki, Norman Saffra, Louis M Weiss, Moshe Szlechter, Herbert B. TanowitzAbstract:Abstract. Ocular Baylisascaris procyonis infection results from ingestion of infective eggs of B. procyonis, the raccoon ascarid. Herpes simplex virus type 2 (HSV-2) infection of the retina is the result of either primary infection or reactivated disease. Herein, we report a case of a 12-year-old female resident of the Bronx in New York City, who presented with pan-uveitis and vision loss. Initial evaluation for etiologic causes was nondiagnostic. Serology for anti-Baylisascaris procyonis antibodies in serum and vitreous fluid were both positive. Polymerase chain reaction (PCR) of vitreous fluid was positive for HSV-2. Treatment with vitrectomy, albendazole, and acyclovir resulted in mild improvement of visual acuity. The atypical presentation of B. procyonis in this case, as ocular larva migrans with a peripheral granuloma and retinal detachment, underscores the importance of maintaining a high degree of suspicion for this pathogen even in non-diffuse unilateral subacute neuroretinitis (DUSN) patients in urban areas. This case further illustrates that it is possible to have coexisting infections in cases of posterior uveitis.
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Baylisascaris larva migrans
Handbook of Clinical Neurology, 2013Co-Authors: Kevin R Kazacos, Linda A Jelicks, Herbert B. TanowitzAbstract:: Baylisascaris procyonis is a roundworm of the raccoon found primarily in North America but also known to occur in other parts of the world including South America, Europe, and Japan. Migration of the larvae of this parasite is recognized as a cause of clinical neural larva migrans (NLM) in humans, primarily children. It is manifested as meningoencephalitis associated with marked eosinophilia of the cerebrospinal fluid and peripheral blood. Diagnosis is made by recovering and identifying larvae in or from the tissues, epidemiological history, serology, and imaging of the central nervous system. Treatment is with albendazole and steroids, although the prognosis is generally poor. This parasite can also cause ocular larva migrans (OLM) which usually presents as diffuse unilateral subacute neuroretinitis (DUSN). The ocular diagnosis can be made by visualizing the larva in the eye and by serology. Intraocular larvae can be destroyed by photocoagulation although albendazole and steroids may also be used. However, once visual disturbance is established the prognosis for improved vision is poor. Related Baylisascaris species occur in skunks, badgers, and certain other carnivores, although most cases of NLM are caused by B. procyonis. Baylisascaris procyonis has also been found in kinkajous in the USA and South America and may also occur in related procyonids (coatis, olingos, etc.).
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Baylisascaris Procyonis Induced Diffuse Unilateral Subacute Neuroretinitis in New York City.
Journal of Neuroparasitology, 2010Co-Authors: Norman A. Saffra, Kevin R Kazacos, Jason E. Perlman, Rajen U. Desai, Christina M. Coyle, Fabiana S. Machado, Sanjay Kedhar, Michael Engelbert, Herbert B. TanowitzAbstract:Diffuse unilateral subacute neuroretinitis (DUSN) secondary to raccoon roundworm (Baylisascaris procyonis) infection has been reported in rural and suburban areas of North America and Europe with extant raccoon populations. Here, we present a case of Baylisascaris-induced DUSN from the densely populated borough of Brooklyn in New York City and alert urban ophthalmologists to consider this etiology even in areas not typically thought to be associated with endemic risk factors. Infected raccoons also occur in urban settings, and urban patients may be exposed in surrounding areas. Most patients with Baylisascaris ocular larva migrans-DUSN will not have concomitant neurologic disease; this fact and larval neurotropism are both misconceptions regarding this infection.
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Baylisascaris procyonis neural larva migrans in an infant in new york city
Journal of Neuroparasitology, 2010Co-Authors: Jason E. Perlman, Kevin R Kazacos, Rajen U. Desai, Fabiana S. Machado, Herbert B. Tanowitz, Gavin H Imperato, Susan Schulman, Jon H Edwards, Lucy R Pontrelli, Norman A. SaffraAbstract:Neural larva migrans (NLM) with eosinophilic meningoencephalitis secondary to raccoon roundworm (Baylisascaris procyonis) infection has been reported in rural and suburban areas of North America and Europe with extant raccoon populations. Most cases have occurred in infants less than two years of age exposed to areas of raccoon fecal contamination. Here, we present a case of Baylisascaris-induced NLM from the densely populated borough of Brooklyn in New York City and alert urban pediatricians to consider this cause of clinical neurologic disease even in areas not typically thought to be associated with endemic risk factors. Infected raccoons also occur in urban settings, and urban children may be exposed to environmental areas or materials contaminated with their feces and the parasite’s eggs.
Sriveny Dangoudoubiyam - One of the best experts on this subject based on the ideXlab platform.
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good outcome with early empiric treatment of neural larva migrans due to Baylisascaris procyonis
Pediatrics, 2012Co-Authors: Jurriaan M Peters, Kevin R Kazacos, Sriveny Dangoudoubiyam, Vandana L Madhavan, Robert N Husson, Janet S SoulAbstract:We report a remarkably good outcome in a 14-month-old boy with early clinical diagnosis and aggressive empirical treatment of neural larva migrans caused by the raccoon roundworm Baylisascaris procyonis . He presented with fever, meningismus, lethargy, irritability and asymmetric spastic extremity weakness. Early findings of marked blood and cerebrospinal fluid eosinophilia and of diffuse white matter signal abnormality in the brain and spinal cord on MRI suggested a parasitic encephalomyelitis. Rapid presumptive treatment with albendazole and high-dose steroids halted progression of clinical signs. The diagnosis was confirmed by 2 sequential enzyme-linked immunosorbent assay studies positive for B procyonis serum immunoglobulin G and by Western blot. Field examination with soil sampling yielded infective Baylisascaris eggs. Repeat MRI 3 months later showed atrophy and diffuse, chronic white matter abnormalities, discordant with the marked clinical improvement in this interval. At 10 months, residual neurologic deficits included subtle paraparesis and moderate language delay. This case is the first in which spinal involvement in human Baylisascaris infection was clinically suspected and confirmed by neuroimaging. Importantly, early diagnosis and aggressive treatment of Baylisascaris meningo-encephalitis and myelitis with albendazole and high-dose steroids likely contributed to the good outcome in this patient, in contrast with previous reports. * Abbreviations: CSF — : cerebrospinal fluid ELISA — : enzyme-linked immunosorbent assay Ig — : immunoglobulin NLM — : neural larva migrans OD — : optical density
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recombinant antigen based enzyme linked immunosorbent assay for diagnosis of Baylisascaris procyonis larva migrans
Clinical and Vaccine Immunology, 2011Co-Authors: Sriveny Dangoudoubiyam, Ramesh Vemulapalli, Momar Ndao, Kevin R KazacosAbstract:Baylisascaris larva migrans is an important zoonotic disease caused by Baylisascaris procyonis, the raccoon roundworm, and is being increasingly considered in the differential diagnosis of eosinophilic meningoencephalitis in children and young adults. Although a B. procyonis excretory-secretory (BPES) antigen-based enzyme-linked immunosorbent assay (ELISA) and a Western blot assay are useful in the immunodiagnosis of this infection, cross-reactivity remains a major problem. Recently, a recombinant B. procyonis antigen, BpRAG1, was reported for use in the development of improved serological assays for the diagnosis of Baylisascaris larva migrans. In this study, we tested a total of 384 human patient serum samples in a BpRAG1 ELISA, including samples from 20 patients with clinical Baylisascaris larva migrans, 137 patients with other parasitic infections (8 helminth and 4 protozoan), and 227 individuals with unknown/suspected parasitic infections. A sensitivity of 85% and a specificity of 86.9% were observed with the BpRAG1 ELISA, compared to only 39.4% specificity with the BPES ELISA. In addition, the BpRAG1 ELISA had a low degree of cross-reactivity with antibodies to Toxocara infection (25%), while the BPES antigen showed 90.6% cross-reactivity. Based on these results, the BpRAG1 antigen has a high degree of sensitivity and specificity and should be very useful and reliable in the diagnosis and seroepidemiology of Baylisascaris larva migrans by ELISA.
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molecular cloning of an immunogenic protein of Baylisascaris procyonis and expression in escherichia coli for use in developing improved serodiagnostic assays
Clinical and Vaccine Immunology, 2010Co-Authors: Sriveny Dangoudoubiyam, Ramesh Vemulapalli, Kathy Hancock, Kevin R KazacosAbstract:Larva migrans caused by Baylisascaris procyonis is an important zoonotic disease. Current serological diagnostic assays for this disease depend on the use of the parasite's larval excretory-secretory (ES) antigens. In order to identify genes encoding ES antigens and to generate recombinant antigens for use in diagnostic assays, construction and immunoscreening of a B. procyonis third-stage larva cDNA expression library was performed and resulted in identification of a partial-length cDNA clone encoding an ES antigen, designated repeat antigen 1 (RAG1). The full-length rag1 cDNA contained a 753-bp open reading frame that encoded a protein of 250 amino acids with 12 tandem repeats of a 12-amino-acid long sequence. The rag1 genomic DNA revealed a single intron of 837 bp that separated the 753-bp coding sequence into two exons delimited by canonical splice sites. No nucleotide or amino acid sequences present in the GenBank databases had significant similarity with those of RAG1. We have cloned, expressed, and purified the recombinant RAG1 (rRAG1) and analyzed its diagnostic potential by enzyme-linked immunosorbent assay. Anti-Baylisascaris species-specific rabbit serum showed strong reactivity to rRAG1, while only minimal to no reactivity was observed with sera against the related ascarids Toxocara canis and Ascaris suum, strongly suggesting the specificity of rRAG1. On the basis of these results, the identified RAG1 appears to be a promising diagnostic antigen for the development of serological assays for specific detection of B. procyonis larva migrans.
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Evaluation of a molecular beacon real-time PCR assay for detection of Baylisascaris procyonis in different soil types and water samples
Parasitology Research, 2009Co-Authors: Rachel R. Gatcombe, Kevin R Kazacos, Sriveny Dangoudoubiyam, Narayanan Jothikumar, Vincent R. HillAbstract:Baylisascaris procyonis is a helminth parasite commonly found in North American raccoons ( Procyon lotor ) that is a cause of clinical neural, ocular, and visceral larva migrans in humans when infective eggs are ingested. Rapid detection of B. procyonis eggs in contaminated soil and water would assist public health analysts in evaluating risks associated with public exposure to areas of known raccoon activity. In this study, a molecular beacon probe-based real-time polymerase chain reaction (PCR) assay was developed to enable rapid and specific detection of eggs of Baylisascaris spp. The molecular beacon assay targeted the cytochrome oxidase subunit 2 (cox-2) gene of B. procyonis . To determine method sensitivity, experiments testing various egg levels (250, 25, and five eggs) were performed by seeding into 0.5-g soil samples or 0.5-mL water samples. Different soil sample types were extracted using a commercial nucleic acid extraction kit. Specificity testing using previously characterized helminth tissue specimens indicated that the assay was specific to Baylisascaris spp. Little real-time PCR inhibition was observed for most of the soil and water samples. A seed level of 250 eggs was detected for all soil types, and two seed levels (25 and five eggs) were detected for surface water samples. These results demonstrate that the reported real-time PCR assay was effective for the sensitive detection of B. procyonis in a wide range of soil types, and should be a useful tool for investigations of soil or water potentially contaminated with eggs of this parasite.
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differentiation of larva migrans caused by Baylisascaris procyonis and toxocara species by western blotting
Clinical and Vaccine Immunology, 2009Co-Authors: Sriveny Dangoudoubiyam, Kevin R KazacosAbstract:Baylisascaris procyonis and Toxocara species are two important causes of larva migrans in humans. Larva migrans caused by Toxocara spp. is well known and is diagnosed serologically by enzyme immunoassay. Over a dozen cases of larva migrans and associated eosinophilic encephalitis caused by B. procyonis have also been reported, and at least a dozen additional cases are known. An enzyme-linked immunosorbent assay (ELISA) using the excretory-secretory (ES) antigen of B. procyonis larvae is currently being used in our laboratory as an aid in the diagnosis of this infection in humans. Clinically affected individuals show very high reactivity (measured as the optical density) on this ELISA; however, a one-way cross-reactivity with Toxocara spp. has been observed. As an approach to differentiate these two infections based on serology, we performed Western blots, wherein the B. procyonis ES antigen was reacted with serum samples from individuals known to be positive for either Toxocara spp. or B. procyonis larva migrans. Western blot results showed that B. procyonis antigens of between 30 and 45 kDa were specifically identified only by the sera from individuals with Baylisascaris larva migrans, thus allowing for differentiation between the two infections. This included human patient serum samples submitted for serologic testing, as well as sera from rabbits experimentally infected with B. procyonis. When used in conjunction with the ELISA, Western blotting could be an efficient tool for diagnosis of this infection in humans.
O G W Berlin - One of the best experts on this subject based on the ideXlab platform.
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Baylisascaris procyonis in california
Emerging Infectious Diseases, 2004Co-Authors: Laurel Moore, Frank Sorvillo, O G W BerlinAbstract:To the Editor: We read with interest the article of Roussere et al. on the distribution of Baylisascaris procyonis eggs in northern California communities (1). The widespread dissemination and high density of raccoon latrines in residential areas clearly pose potential health risks, particularly to young children. While California has reported more cases of baylisascariasis than any other state, few published studies have reported on the distribution and prevalence of this helminth in the region. In 2001, we conducted a study to determine the presence of B. procyonis in the Santa Barbara area by examining roadkill raccoons recovered by animal control staff and stored in a refrigerated facility. On examination, the digestive tract from the stomach to the rectum was removed and tested for B. procyonis worms and eggs. Of 26 raccoons examined, 24 (92%, 95% confidence interval 75%–99%) were positive for B. procyonis infection. B. procyonis worms were found in 85% of the animals examined and eggs were found in 73%. Pet food was frequently found (43%) in the stomach contents of examined raccoons, indicating that such food was made accessible to these animals, either intentionally or inadvertently by residents. B. procyonis has been identified along the central coast of California, which expands the known range of this helminthic zoonotic agent. This finding, coupled with other published studies, indicates that Baylisascaris may be prevalent throughout the state (1,2). Although our study was based on a small sample of selected raccoons, the high infection rate is cause for concern and indicates the potential for human exposure. A presumptive case of B. procyonis infection in an 11-month-old child was reported in Santa Barbara in 2003 (1). Determining the distribution and prevalence of B. procyonis is necessary to inform local healthcare providers, public health authorities, and the public of the potential risk. Using road-kill raccoons is a relatively easy method for quickly assessing the presence of B. procyonis in a community. Also, this approach avoids trapping and handling live animals and allows stomach contents to be examined to determine where raccoons are feeding. Data from such assessments must be interpreted with caution, since they may not represent all raccoons in an area.
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Baylisascaris procyonis an emerging helminthic zoonosis
Emerging Infectious Diseases, 2002Co-Authors: Frank Sorvillo, O G W Berlin, Stephen A MorseAbstract:Baylisascaris procyonis, a roundworm infection of raccoons, is emerging as an important helminthic zoonosis, principally affecting young children. Raccoons have increasingly become peridomestic animals living in close proximity to human residences. When B. procyonis eggs are ingested by a host other than a raccoon, migration of larvae through tissue, termed larval migrans, ensues. This larval infection can invade the brain and eye, causing severe disease and death. The prevalence of B. procyonis infection in raccoons is often high, and infected animals can shed enormous numbers of eggs in their feces. These eggs can survive in the environment for extended periods of time, and the infectious dose of B. procyonis is relatively low. Therefore, the risk for human exposure and infection may be greater than is currently recognized.
