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Toxocariasis of the Nervous System

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Abstract

Purpose

Toxocariasis is a helminthozoonosis caused by the infection of a human host by the larva of Toxocara spp., predominately involving Toxocara canis and Toxocara cati, which are common nematodes in dogs and cats, respectively. Human transmission occurs through contact with animals or by consumption of food contaminated with parasite’s eggs. The purpose of this article is to review the current knowledge regarding human neurotoxocariasis.

Methods

We conducted a systematic review of the existing literature concerning toxocariasis of the nervous system.

Results

Clinical spectrum of human toxocariasis varies widely from a subclinical course to significant organ morbidity. Clinical course depends on parasitic load, the migration route of the larvae and host response. Human neurotoxocariasis is a relatively rare entity yet associated with severe sequelae. Manifestations include meningitis (usually eosinophilic), encephalitis, myelitis, cerebellar vasculitis, space-occupying lesion, behavioral abnormalities, and optic neuritis. Even though valid diagnostic criteria are lacking, neurotoxocariasis should be suspected in patients with neurologic symptoms and cerebrospinal fluid (CSF) pleocytosis with eosinophilia, positive serology for anti-Toxocara antibodies, in serum and/or CSF, sterile CSF and clinical improvement after antihelminthic treatment. Neurotoxocariasis is treated by benzimidazole components, most frequently albendazole, corticosteroids, or diethylcarbamazine.

Conclusion

Parasite larvae migrate through tissues and are able to reach the nervous system causing neurotoxocariasis. Its clinical spectrum varies and includes myelitis, meningoencephalitis, brain abscess, and vasculitis. Neurotoxocariasis should always be suspected in patients with neurologic symptoms accompanied by eosinophilia in blood and/or CSF. Early diagnosis and treatment could prevent long-term neurologic impairment.

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References

  1. Garcia HH, Modi M (2008) Helminthic parasites and seizures. Epilepsia 49(Suppl 6):25–32

    PubMed  Google Scholar 

  2. Musso C, Lemos EM, Tsanaclis AM et al (2006) Toxocara infection is not associated with viral or bacterial central nervous system infection in children. Neuropediatrics 37(3):126–129

    CAS  PubMed  Google Scholar 

  3. Walker MD, Zunt JR (2005) Neuroparasitic infections: nematodes. Semin Neurol 25(3):252–261

    CAS  PubMed  PubMed Central  Google Scholar 

  4. Ural S, Özer B, Gelal F et al (2016) Transverse myelitis associated with toxocariasis and the importance of locally produced antibodies for diagnosis. Mikrobiyol Bul 50(3):478–483

    PubMed  Google Scholar 

  5. Uspenskiĭ AV, Peshkov RA, Gorokhov VV et al (2011) Toxocariasis under the present conditions. Med Parazitol (Mosk) 2:3–6

    Google Scholar 

  6. Abo-Shehada MN, Herbert IV (1984) The migration of larval Toxocara canis in mice. II. Post-intestinal migration in primary infections. Vet Parasitol 17:75–83

    CAS  PubMed  Google Scholar 

  7. Mitamura M, Fukuoka M, Haruta Y et al (2007) A case of visceral larva migrans due to Toxocara canis showing varied manifestations. Kansenshogaku Zasshi 81(3):305–308

    PubMed  Google Scholar 

  8. Sánchez SS, García HH, Nicoletti A (2018) Clinical and magnetic resonance imaging findings of neurotoxocariasis. Front Neurol 9:53

    PubMed  PubMed Central  Google Scholar 

  9. Dubinský P, Havasiová-Reiterová K, Petko B et al (1995) Role of small mammals in the epidemiology of toxocariasis. Parasitology 110(Pt 2):187–193

    PubMed  Google Scholar 

  10. Hotez PJ (1993) Visceral and ocular larva migrans. Semin Neurol 13(2):175–179

    CAS  PubMed  Google Scholar 

  11. Washburn TC, Medearis DN, Childs B (1965) Sex differences in susceptibility to infection. Pediatrics 35:57–62

    CAS  PubMed  Google Scholar 

  12. Castro SE, Medawar PB, Hamilton DNH (1973) Orchidectomy as a method of immunopotentiation in mice. In: Wolstenholme GEW, Knight J (eds) Immunopotentiation. CIBA Foundation Symposium (18 new series). Associated Scientific, Amsterdam, pp 258–273

    Google Scholar 

  13. Abo-Shehada MN, Herbert IV (1989) Variations in innate resistance to experimental Toxocara canis infection in two strains of mice. Vet Parasitol 33:297–307

    CAS  PubMed  Google Scholar 

  14. Van Den Broucke S, Kanobana K, Polman K et al (2015) Toxocariasis diagnosed in international travelers at the Institute of Tropical Medicine, Antwerp, Belgium, from 2000 to 2013. PLoS Negl Trop Dis 9(3):e0003559

    Google Scholar 

  15. Abir B, Malek M, Ridha M (2017) Toxocariasis of the central nervous system: with report of two cases. Clin Neurol Neurosurg 154:94–97

    PubMed  Google Scholar 

  16. Nicoletti A (2013) Toxocariasis. Handb Clin Neurol 114:217–228

    PubMed  Google Scholar 

  17. Magnaval JF, Galindo V, Glickman LT et al (1997) Human Toxocara infection of the central nervous system and neurological disorders: a case-control study. Parasitology 115(Pt 5):537–543

    PubMed  Google Scholar 

  18. Deshayes S, Bonhomme J, de La Blanchardière A (2016) Neurotoxocariasis: a systematic literature review. Infection 44(5):565–574

    CAS  PubMed  Google Scholar 

  19. Capo I, Rokvić N (2009) Neuropathology of experimental toxocariasis in Syrian golden hamsters. Med Pregl 62(11–12):603–607

    PubMed  Google Scholar 

  20. Rubinsky-Elefant G, Hirata CE, Yamamoto JH et al (2010) Human toxocariasis: diagnosis, worldwide seroprevalences and clinical expression of the systemic and ocular forms. Ann Trop Med Parasitol 104(1):3–23

    CAS  PubMed  Google Scholar 

  21. Jung JK, Jung JT, Lee CH et al (2007) A case of hepatic abscess caused by toxocara. Korean J Hepatol 13(3):409–413

    PubMed  Google Scholar 

  22. Allahdin S, Khademvatan S, Rafiei A et al (2015) Frequency of Toxoplasma and Toxocara Sp antibodies in epileptic patients, in South Western Iran. Iran J Child Neurol 9(4):32–40

    PubMed  PubMed Central  Google Scholar 

  23. Bächli H, Minet JC, Gratzl O (2004) Cerebral toxocariasis: a possible cause of epileptic seizure in children. Childs Nerv Syst 20(7):468–472

    PubMed  Google Scholar 

  24. Hoffmeister B, Glaeser S, Flick H et al (2007) Cerebral toxocariasis after consumption of raw duck liver. Am J Trop Med Hyg 76(3):600–602

    PubMed  Google Scholar 

  25. Hamilton CM, Stafford P, Pinelli E, Holland CV (2006) A murine model for cerebral toxocariasis: characterization of host susceptibility and behaviour. Parasitology 132(Pt 6):791–801

    CAS  PubMed  Google Scholar 

  26. Othman AA, Abdel-Aleem GA, Saied EM et al (2010) Biochemical and immunopathological changes in experimental neurotoxocariasis. Mol Biochem Parasitol 172(1):1–8

    CAS  PubMed  Google Scholar 

  27. Hamilton CM, Brandes S, Holland CV et al (2008) Cytokine expression in the brains of Toxocara canis-infected mice. Parasite Immunol 30(3):181–185

    CAS  PubMed  Google Scholar 

  28. Good B, Holland CV, Stafford P (2001) The influence of inoculum size and time post-infection on the number and position of Toxocara canis larvae recovered from the brains of outbred CD1 mice. J Helminthol 75(2):175–181

    CAS  PubMed  Google Scholar 

  29. Skerrett H, Holland CV (1997) Variation in the larval recovery of Toxocara canis from the murine brain: implications for behavioural studies. J Helminthol 71(3):253–255

    CAS  PubMed  Google Scholar 

  30. Camparoto ML, Fulan B, Colli CM et al (2008) Initial stage of development and migratory behavior of Toxocara canis larvae in BALB/c mouse experimental model. Genet Mol Res 7(2):444–450

    CAS  PubMed  Google Scholar 

  31. Aldawek AM, Levkut M, Revajová V et al (2002) Larval toxocarosis in sheep: the immunohistochemical characterization of lesions in some affected organs. Vet Parasitol 105(3):207–214

    CAS  PubMed  Google Scholar 

  32. Liao CW, Cho WL, Kao TC et al (2008) Blood–brain barrier impairment with enhanced SP, NK-1R, GFAP and claudin-5 expressions in experimental cerebral toxocariasis. Parasite Immunol 30(10):525–534

    CAS  PubMed  Google Scholar 

  33. Liao CW, Fan CK, Kao TC et al (2008) Brain injury-associated biomarkers of TGF-beta1, S100B, GFAP, NF-L, tTG, AbetaPP, and tau were concomitantly enhanced and the UPS was impaired during acute brain injury caused by Toxocara canis in mice. BMC Infect Dis 8:84

    PubMed  PubMed Central  Google Scholar 

  34. Zachariah SB, Zachariah B, Varghese R (1994) Neuroimaging studies of cerebral "visceral larva migrans" syndrome. J Neuroimaging 4(1):39–40

    CAS  PubMed  Google Scholar 

  35. Gargili A, Demirci C, Kandil A et al (2004) In vivo inhibition of inducible nitric oxide and evaluation of the brain tissue damage induced by Toxocara canis larvae in experimentally infected mice. Chin J Physiol 47(4):189–196

    CAS  PubMed  Google Scholar 

  36. Lai SC, Chen KM, Chen HC et al (2005) Induction of matrix metalloproteinase-9 in mice during Toxocara canis larvae migration. Parasitol Res 95(3):193–200

    CAS  PubMed  Google Scholar 

  37. Abo-Shehada MN, AI-Zubaidy BA, Herbert IV (1991) Acquired immunity to Toxocara canis infection in mice. Vet Parasitol 38:289–298

    CAS  PubMed  Google Scholar 

  38. Ollero MD, Fenoy S, Cuéllar C et al (2008) Experimental toxocariosis in BALB/c mice: effect of the inoculation dose on brain and eye involvement. Acta Trop 105(2):124–130

    CAS  PubMed  Google Scholar 

  39. Hayashi E, Akao N, Fujita K (2003) Evidence for the involvement of the optic nerve as a migration route for larvae in ocular toxocariasis of Mongolian gerbils. J Helminthol 77(4):311–315

    CAS  PubMed  Google Scholar 

  40. Fortenberry JD, Kenney RD, Younger J (1991) Visceral larva migrans producing static encephalopathy in an infant. Pediatr Infect Dis J 10(5):403–406

    CAS  PubMed  Google Scholar 

  41. Mok CH (1968) Visceral larva migrans. A discussion based on review of the literature. Clin Pediatr (Phila) 7(9):565–573

    CAS  Google Scholar 

  42. Summers B, Cypess RH, Dolinsky ZS et al (1983) Neuropathological studies of experimental toxocariasis in lead exposed mice. Brain Res Bull 10(4):547–550

    CAS  PubMed  Google Scholar 

  43. Cardillo N, Rosa A, Ribicich M et al (2009) Experimental infection with Toxocara cati in BALB/c mice, migratory behaviour and pathological changes. Zoonoses Public Health 56(4):198–205

    CAS  PubMed  Google Scholar 

  44. Oryan A, Sadjjadi SM, Azizi S (2010) Longevity of Toxocara cati larvae and pathology in tissues of experimentally infected chickens. Korean J Parasitol 48(1):79–80

    PubMed  PubMed Central  Google Scholar 

  45. Erdem Kivrak E, Sıpahi OR, Korkmaz M et al (2014) A rarely seen cause of brain abscess: neurotoxocariasis. Mikrobiyol Bul 48(3):507–511

    PubMed  Google Scholar 

  46. Finsterer J, Auer H (2007) Neurotoxocarosis. Rev Inst Med Trop Sao Paulo 49(5):279–287

    PubMed  Google Scholar 

  47. Dolinsky ZS, Burright RG, Donovick PJ et al (1981) Behavioral effects of lead and toxocara canis in mice. Science, New Series 213(4512):1142–1144

    CAS  Google Scholar 

  48. Dolinsky ZS, Hardy CA, Burright RG et al (1985) The progression of behavioral and pathological effects of the parasite Toxocara canis in the mouse. Physiol Behav 35(1):33–42

    CAS  PubMed  Google Scholar 

  49. Donovick P, Dolinsky ZS, Perdue PV et al (1981) Toxocara canis and lead alter consummatory behavior in mice. Brain Res Bull 7:317–323

    CAS  PubMed  Google Scholar 

  50. Donovick P, Burright R (1987) The consequences of parasitic infection for the behavior of the mammalian host. Environ Health Perspect 73:247–250

    CAS  PubMed  PubMed Central  Google Scholar 

  51. Moreira-Silva SF, Rodrigues MG, Pimenta JL et al (2004) Toxocariasis of the central nervous system: with report of two cases. Rev Soc Bras Med Trop 37(2):169–174

    PubMed  Google Scholar 

  52. Strupp M, Pfister HW, Eichenlaub S et al (1999) Meningomyelitis in a case of toxocariasis with markedly isolated CSF eosinophilia and an MRI-documented thoracic cord lesion. J Neurol 246(8):741–744

    CAS  PubMed  Google Scholar 

  53. Kim DE, Park JY, Ha H et al (2017) Cluster-like headache secondary to focal cervical myelitis. Neurologist 22(4):138–140

    PubMed  Google Scholar 

  54. Fukae J, Kawanabe T, Akao N et al (2012) Longitudinal myelitis caused by visceral larva migrans associated with Toxocara cati infection: case report. Clin Neurol Neurosurg 114(7):1091–1094

    PubMed  Google Scholar 

  55. Singer OC, Conrad F, Jahnke K et al (2011) Severe meningoencephalomyelitis due to CNS-Toxocarosis. J Neurol 258(4):696–698

    PubMed  Google Scholar 

  56. Vidal JE, Sztajnbok J, Seguro AC (2003) Eosinophilic meningoencephalitis due to Toxocara canis: case report and review of the literature. Am J Trop Med Hyg 69(3):341–343

    PubMed  Google Scholar 

  57. Oujamaa L, Sibon I, Vital A et al (2003) Cerebral vasculitis secondary to Toxocara canis and Fasciola hepatica co-infestation. Rev Neurol (Paris) 159(4):447–450

    CAS  Google Scholar 

  58. Ardiles A, Chanqueo L, Reyes V et al (2001) Toxocariasis in an adult manifested as hypereosinophilic syndrome with predominant neurological involvement Clinical case. Rev Med Chil 129(7):780–785

    CAS  PubMed  Google Scholar 

  59. Komiyama A, Hasegawa O, Nakamura S et al (1995) Optic neuritis in cerebral toxocariasis. J Neurol Neurosurg Psychiatry 59(2):197–198

    CAS  PubMed  PubMed Central  Google Scholar 

  60. Carod-Artal FJ (2009) Tropical causes of epilepsy. Rev Neurol 49(9):475–482

    CAS  PubMed  Google Scholar 

  61. Graeff-Teixeira C, da Silva AC, Yoshimura K (2009) Update on eosinophilic meningoencephalitis and its clinical relevance. Clin Microbiol Rev 22(2):322–348

    CAS  PubMed  PubMed Central  Google Scholar 

  62. Scheid R, Tina Jentzsch R, Schroeter ML (2008) Cognitive dysfunction, urinary retention, and a lesion in the thalamus—beware of possible toxocariasis of the central nervous system. Clin Neurol Neurosurg 110(10):1054–1057

    PubMed  Google Scholar 

  63. Moiyadi A, Mahadevan A, Anandh B et al (2007) Visceral larva migrans presenting as multiple intracranial and intraspinal abscesses. Neuropathology 27(4):371–374

    PubMed  Google Scholar 

  64. Helbok R, Brenneis C, Engelhardt K et al (2007) A rare case of Toxocara canis cerebral vasculitis. Eur J Neurol 14(1):e49

    CAS  PubMed  Google Scholar 

  65. Choi JH, Cho JW, Lee JH et al (2013) Obstructive hydrocephalus due to CNS toxocariasis. J Neurol Sci 329(1–2):59–61

    PubMed  Google Scholar 

  66. Salvador S, Ribeiro R, Winckler MI et al (2010) Pediatric neurotoxocariasis with concomitant cerebral, cerebellar, and peripheral nervous system involvement: case report and review of the literature. J Pediatr (Rio J) 86(6):531–534

    Google Scholar 

  67. Marx C, Lin J, Masruha MR, Rodrigues MG, da Rocha AJ, Vilanova LC, Gabbai AA (2007) Toxocariasis of the CNS simulating acute disseminated encephalomyelitis. Neurology 69(8):806–807

    CAS  PubMed  Google Scholar 

  68. Maiga Y, Wiertlewski S, Desal H et al (2007) Presentation of cerebral toxocariasis with mental confusion in an adult: case report and review of the literature. Bull Soc Pathol Exot 100(2):101–104

    CAS  PubMed  Google Scholar 

  69. Ota KV, Dimaras H, Héon E et al (2009) Toxocariasis mimicking liver, lung, and spinal cord metastases from retinoblastoma. Pediatr Infect Dis J 28(3):252–254

    PubMed  Google Scholar 

  70. Gorgulu A, Albayrak BS, Gorgulu E et al (2006) Postoperative cerebral abscess formation caused by Toxocara canis in a meningioma cavity. J Neurooncol 77(3):325–326

    PubMed  Google Scholar 

  71. Goffette S, Jeanjean AP, Duprez TP et al (2000) Eosinophilic pleocytosis and myelitis related to Toxocara canis infection. Eur J Neurol 7(6):703–706

    CAS  PubMed  Google Scholar 

  72. Delgado O, Botto C, Mattei R et al (1989) Effect of albendazole in experimental toxocariasis of mice. Ann Trop Med Parasitol 83(6):621–624

    CAS  PubMed  Google Scholar 

  73. Xinou E, Lefkopoulos A, Gelagoti M et al (2003) CT and MR imaging findings in cerebral toxocaral disease. AJNR Am J Neuroradiol 24(4):714–718

    CAS  PubMed  Google Scholar 

  74. Kwon HH (2015) Toxocariasis: a rare cause of multiple cerebral infarction. Infect Chemother 47(2):137–141

    PubMed  PubMed Central  Google Scholar 

  75. Caldera F, Burlone ME, Genchi C et al (2013) Toxocara encephalitis presenting with autonomous nervous system involvement. Infection 41(3):691–694

    CAS  PubMed  Google Scholar 

  76. Lompo LD, Kamdem FK, Revenco E et al (2012) Toxocara canis cerebral vasculitis revealed by iterative strokes. Rev Neurol (Paris) 168(6–7):533–537

    Google Scholar 

  77. Feske SK, Goldberg M, Dudzinski DM et al (2015) Case records of the Massachusetts General Hospital. Case 29–2015. A 38-year-old pregnant woman with headache and visual symptoms. N Engl J Med 373(12):1154–1164

    CAS  PubMed  Google Scholar 

  78. Dinić-Uzurov V, Lalosević V, Milosević I et al (2007) Current differential diagnosis of hypereosinophilic syndrome. Med Pregl 60(11–12):581–586

    PubMed  Google Scholar 

  79. Carvalho EA, Rocha RL (2011) Toxocariasis: visceral larva migrans in children. J Pediatr (Rio J) 87(2):100–110

    Google Scholar 

  80. Sarimehmetoğlu HO, Burgu A, Aycicek H et al (2001) Application of western blotting procedure for the immunodiagnosis of visceral larva migrans in mice by using excretory/secretory antigens. Dtsch Tierarztl Wochenschr 108(9):390–392

    PubMed  Google Scholar 

  81. Woodhall DM, Fiore AE (2014) Toxocariasis: a review for pediatricians. J Pediatric Infect Dis Soc 3(2):154–159

    PubMed  Google Scholar 

  82. Ruttinger P, Hadidi H (1991) MRI in cerebral toxocaral disease. J Neurol Neurosurg Psychiatry 54:361–362

    CAS  PubMed  PubMed Central  Google Scholar 

  83. Lee IH, Kim ST, Oh DK et al (2010) MRI findings of spinal visceral larva migrans of Toxocara canis. Eur J Radiol 75(2):236–240

    PubMed  Google Scholar 

  84. Umehara F, Ookatsu H, Hayashi D et al (2006) MRI studies of spinal visceral larva migrans syndrome. J Neurol Sci 249(1):7–12

    PubMed  Google Scholar 

  85. Dymon M, Papir B (2004) Effect of anthelmintic therapy supplemented with glucan in experimental toxocarosis. Wiad Parazytol 50(3):465–470

    PubMed  Google Scholar 

  86. Horiuchi A, Satou T, Akao N et al (2005) The effect of free and polyethylene glycol-liposome-entrapped albendazole on larval mobility and number in Toxocara canis infected mice. Vet Parasitol 129(1–2):83–87

    CAS  PubMed  Google Scholar 

  87. Dvoroznáková E, Borosková Z, Dubinský P et al (1999) Immunomodulative effect of muramyldipeptide in mice with larval toxocarosis. Parasitol Res 85(12):1034–1040

    PubMed  Google Scholar 

  88. Bardón R, Cuéllar C, Guillén JL (1995) Evaluation by larval recovery of mebendazole activity in experimental murine toxocariasis. Int J Parasitol 25(5):587–592

    PubMed  Google Scholar 

  89. Fok E, Kassai T (1998) Toxocara canis infection in the paratenic host: a study on the chemosusceptibility of the somatic larvae in mice. Vet Parasitol 74(2–4):243–259

    CAS  PubMed  Google Scholar 

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Authors and Affiliations

  1. Infectious Diseases Unit, 3rd Department of Internal Medicine, Red Cross Hospital, Athens, Greece

    Maria Meliou

  2. “C.N.S. Alliance” Research Group, Athens, Greece

    Maria Meliou, Ioannis N. Mavridis, Efstratios-Stylianos Pyrgelis & Eleni Agapiou

  3. 1st Department of Neurology, Medical School, “Eginition” Hospital, National and Kapodistrian University of Athens, Athens, Greece

    Efstratios-Stylianos Pyrgelis

  4. Department of Physical Medicine and Rehabilitation, “Asklepieion” General Hospital, Voula, Athens, Greece

    Eleni Agapiou

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  1. Maria Meliou
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Meliou, M., Mavridis, I.N., Pyrgelis, ES. et al. Toxocariasis of the Nervous System. Acta Parasit. 65, 291–299 (2020). https://doi.org/10.2478/s11686-019-00166-1

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