Pediatric Toxocariasis

Pediatric Toxocariasis

No Results

No Results


Toxocariasis is caused by Toxocara canis (T. canis) and, less frequently, Toxocara catis (T. catis), which are intestinal nematodes (roundworms) found in dogs and cats, respectively. In humans, toxocariasis is considered an aberrant infection because humans are incidental hosts, as the parasites cannot successfully reach full maturity in the human body. Instead, the invasive larvae migrate for months through different organs until they are overcome by the human inflammatory reaction and die. The larvae can survive in tissues for at least 9 years and, possibly, for the entire life of the host.

Three clinical forms of toxocariasis are traditionally described; these are visceral larva migrans (VLM), ocular larva migrans (OLM), and covert toxocariasis (common toxocariasis). [1] A constellation of differing disease manifestations have been attributed to each of these clinical forms. [2]

Diagnosis is based on clinical and serologic findings. In addition to enzyme-linked immunosorbent assay (ELISA), polymerase chain reaction (PCR) is being researched as a possible diagnostic tool. Stool examination for Toxocara larvae is not a helpful diagnostic test for toxocariasis. Whether or not the infection should be treated and, if so, when and how it should be treated is controversial. The anthelmintic agents, mebendazole, thiabendazole, albendazole, and diethylcarbamazine, are medication options used in treatment. Corticosteroids also have a significant role in therapy. See the images below.

Most frequently, human toxocariasis is caused by T. canis, a nematode roundworm of the family Ascaridae. Adult T. canis female worms are usually found in young puppies and lactating female dogs. The adult T. canis female worms can excrete as many as 200,000 eggs per day. These eggs require about 2 to 5 weeks of optimal environmental conditions (temperatures of 10-35°C, high soil humidity) to develop from a noninfective unembryonated form to an infective embryonated egg. Embryonated eggs are resistant to freezing, moisture, and extreme pH levels.

When a dog ingests infective eggs, the eggs hatch into larvae in the proximal small intestine. The larvae then penetrate the intestinal wall, and gain access to the blood and lymphatic circulation. The larvae invade the dog’s liver, lungs, and other tissues. In most dogs, the larval maturation process is arrested in most tissues. However in the pregnant female, T. canis continues developing and migrates across the placenta, infecting canine fetuses. After the birth of the puppies, the larvae continue to mature migrating from the lungs to the gastrointestinal tract via the trachea. The larvae reach maturity in the puppies’ intestinal tracts. Post-partum, the lactating female dog is re-infected while caring for her young. Therefore, the primary sources of T. canis eggs are puppies less than 3 months old and lactating female dogs.

Humans are paratenic hosts for T. canis. Paratenic hosts are transport hosts in which the larvae never mature into adult worms. The infection is acquired through ingestion of soil containing infective T. canis eggs. Theseeggs are found in areas where dogs defecate, such as playgrounds, outdoor public areas and dog parks. As much as 20-30% of soil samples from public parks and children’s sandboxes are contaminated with Toxocara eggs. Infections acquired through ingestion of raw snails and raw lamb have also been reported.

The cat roundworm, T. catis, has a similar life cycle to T. canis. A noted difference is that vertical transmission is due to lactation more than transplacental transmission. Humans are paratenic hosts; however, there have been some cases reported of mature worm T. catis intestinal infections in children. Overall, T. catis causes fewer cases of human infection than T. canis, probably due to the defecation patterns of cats, which make environmental infestation less frequent. As such, this article focuses on T. canis infections.

Tissue damage in Toxocariasis is due to the host inflammatory reaction more than the infection itself. The larvae produce glycosylated proteins, usually referred to as Toxocara excretory-secretory (TES) antigens. These antigens induce a Th2-type CD4+ T-cell immune response characterized by production of interleukin 4 (IL-4) that promotes the switching of B-cell isotypes to the production of immunoglobulin E (IgE) and interleukin 5 (IL-5). These, in turn, promote eosinophil differentiation and vascular adhesion.

Although Toxocara organisms are the most common causes of visceral larva migrans (VLM) syndrome, case reports have cited other zoonotic nematodes that cause VLM, including Ascaris suum, [3] Baylisascaris procyonis (raccoon ascarid), and Lagochilascaris minor (opossum ascarid).

T. canis infections occur in canine animals throughout the world, as confirmed by seroepidemiologic studies. The prevalence of seropositivity varies not only from country to country but also in different regions within a country. [4] The real prevalence of toxocariasis is difficult to estimate because serologic diagnostic tests are performed only when the diagnosis is suspected, and most human Toxocara infections are asymptomatic.

United States

Toxocariasis is a public health problem. The prevalence of infection in different communities is directly proportional to the infection rates among canines and the free access of dogs to public places. Obviously, the higher the rate of infected dogs and the easier their access to public places, the more easily humans are exposed to infective eggs. Because eggs need weeks in the soil to become infective, direct contact with young puppies is not a risk factor for acquiring disease. Young children are at higher risk because of their play habits and their tendency to have oral behaviors such as putting their fingers in their mouths. Children with geophagic pica (the compulsion to consume earth, soil, or clay), children who have contact with puppy litters, and children who are mentally challenged with abnormal oral behaviors are particularly at risk. In tropical climates, clay soil types, warm temperature and humidity favor the embryonization and viability of Toxocara eggs.

In the United States, the seroprevalence of children, as measured with enzyme-linked immunosorbent assay (ELISA) that employs TES antigens, varies from 4-8%. Seroprevalence is higher in Puerto Rico and the southeastern states and then in the western, mid-western and mid-Atlantic states. Black and Latino peoples have rates of 16-30%. Prevalence is also higher in underserved urban areas of the United States. [5] Immigrants from Latin America are also at risk for VLM. [6]


The prevalence of human toxocariasis in tropical regions of the world is higher than in the United States. [7, 8, 9, 10, 11, 12] The highest seroprevalence ever recorded was in a village of Santa Lucia, West Indies. Here, the prevalence was 86% in children aged 6 months to 6 years. This community had an extraordinarily high rate of T. canis infection explained by peridomestic areas contaminated with canine waste and geophagic pica behavior among children. Serologic surveys in different countries reveal seropositivity rates of 19% in the Netherlands, 2.5% in Germany, 39% in Brazil, 5.8-36% in the Czech Republic, 0-37% in Spain, 5.2% in Cuba, [13, 14] 10.9 % in Jordan, 47.5% in Colombia, 81% in Nepal, and 13% in the Slovak Republic. [15]

A study conducted in a tropical region of Venezuela illustrates the greater risk for disadvantaged sectors of society in acquiring this infection. [16] In this study, only 1.8% of middle-class urban subjects had positive findings, compared with 20% of urban-slum dwellers, 25% of rural farmers, and 35% of Amazon Indians. In Bolivia, toxocariasis was thought to be a significant cause of epilepsy, particularly partial epilepsy.

In an epidemiological, cross-sectional study in 252 schoolchildren (ages 1-12 years old) in Brazil, seroprevalence of IgG anti-Toxocara antibodies was found to be 15.5%. An ELISA test based on TES antigens was used to determine outcomes. Geophagic pica was associated with increased prevalence. Thorough hand-washing before meals was associated with decreased seroprevalence. [17]

Although sudden death due to T. canis infestation has been reported, mortality is unusual. The major morbid condition is decreased visual acuity caused by ocular larva migrans (OLM). Evidence suggests that toxocariasis may be a causative factor for allergic asthma.

Boys usually have higher seroprevalence than girls. This is probably related to differences in play behavior.

Individuals of all ages are at risk. VLM associated with severe symptoms occurs mainly in young children, age 18 months to 3 years old. Children within this age group who engage in geophagic pica have greater risk in an environment contaminated with Toxocara eggs. The infective worm burden along with the host response, determines the level of infestation and disease severity. [18] Overall, VLM is diagnosed primarily in children, age 1-7 years. OLM occurs more often in older children, adolescents and young adults.

Mazur-Melewska K, Mania A, Figlerowicz M, Kemnitz P, Sluzewski W, Michalak M. The influence of age on a clinical presentation of Toxocara spp. infection in children. Ann Agric Environ Med. 2012. 19(2):233-6. [Medline].

Knopp S, Steinmann P, Keiser J, Utzinger J. Nematode infections: soil-transmitted helminths and trichinella. Infect Dis Clin North Am. 2012 Jun. 26(2):341-58. [Medline].

Maruyama H, Nawa Y, Noda S, et al. An outbreak of visceral larva migrans due to Ascaris suum in Kyushu, Japan. Lancet. 1996 Jun 22. 347(9017):1766-7. [Medline].

Congdon P, Lloyd P. Toxocara infection in the United States: the relevance of poverty, geography and demography as risk factors, and implications for estimating county prevalence. Int J Public Health. 2011 Feb. 56(1):15-24. [Medline].

Red Book. Toxocariasis. 2009 Report of the Committee on Infectious Diseases. 28th ed. American Academy of Pediatrics. 2009. 666-67.

Turrientes MC, Perez de Ayala A, Norman F, Navarro M, Perez-Molina JA, Rodriquez-Ferrer M, et al. Visceral larva migrans in immigrants from latin america. Emerg Infect Dis. 2011 Jul. 17(7):1263-5. [Medline].

Nkouawa A, Sako Y, Itoh S, et al. Serological studies of neurologic helminthic infections in rural areas of southwest cameroon: toxocariasis, cysticercosis and paragonimiasis. PLoS Negl Trop Dis. 2010 Jul 6. 4(7):e732. [Medline]. [Full Text].

Colli CM, Rubinsky-Elefant G, Paludo ML, et al. Serological, clinical and epidemiological evaluation of toxocariasis in urban areas of south Brazil. Rev Inst Med Trop Sao Paulo. 2010 Apr. 52(2):69-74. [Medline].

Espinoza YA, Huapaya PE, Roldan WH, et al. Seroprevalence of human toxocariasis in Andean communities from the Northeast of Lima, Peru. Rev Inst Med Trop Sao Paulo. 2010 Feb. 52(1):31-6. [Medline].

Liao CW, Sukati H, D’Lamini P, et al. Seroprevalence of Toxocara canis infection among children in Swaziland, southern Africa. Ann Trop Med Parasitol. 2010 Jan. 104(1):73-80. [Medline].

Akdemir C. Visceral larva migrans among children in Kütahya (Turkey) and an evaluation of playgrounds for T. canis eggs. Turk J Pediatr. 2010 Mar-Apr. 52(2):158-62. [Medline].

Elshazly AM, Attia G, El-Ghareeb AS, Belal US. Clinical varieties of Toxocariasis canis in Children’s Hospital, Mansoura University: is it an underestimated problem?. J Egypt Soc Parasitol. 2011 Aug. 41(2):263-74. [Medline].

Kanobana K, Vereecken K, Junco Diaz R, Sariego I, Rojas L, Bonet Gorbea M, et al. Toxocara seropositivity, atopy and asthma: a study in Cuban schoolchildren. Trop Med Int Health. 2013 Feb 8. [Medline].

Sariego I, Kanobana K, Junco R, Vereecken K, Núñez FA, Polman K, et al. Frequency of antibodies to Toxocara in Cuban schoolchildren. Trop Med Int Health. 2012 Jun. 17(6):711-4. [Medline].

Pinelli E, Herremans T, Harms MG, Hoek D, Kortbeek LM. Toxocara and Ascaris seropositivity among patients suspected of visceral and ocular larva migrans in the Netherlands: trends from 1998 to 2009. Eur J Clin Microbiol Infect Dis. 2011 Jul. 30(7):873-9. [Medline].

Lynch NR, Eddy K, Hodgen AN, et al. Seroprevalence of Toxocara canis infection in tropical Venezuela. Trans R Soc Trop Med Hyg. 1988. 82(2):275-81. [Medline].

Cassenote AJ, Lima AR, Pinto Neto JM, Rubinsky-Elefant G. Seroprevalence and modifiable risk factors for Toxocara spp. in Brazilian schoolchildren. PLoS Negl Trop Dis. 2014 May. 8(5):e2830. [Medline]. [Full Text].

Oski FA, et al. Protozoan Parasites. Toxocariasis. Principles and Practices of Pediatrics. 2nd edition. Philadelphia, PA: JB Lippincott; 1994. 1405-08.

Hurni MA, Gerbig AW, Braathen LR, Hunziker T. Toxocariasis and Wells’ syndrome: a causal relationship?. Dermatology. 1997. 195(4):325-8. [Medline].

Wolfrom E, Chene G, Lejoly-Boisseau H, Beylot C, Geniaux M, Taieb A. [Chronic urticaria and toxocara canis infection. A case-control study]. Ann Dermatol Venereol. 1996. 123(4):240-6. [Medline].

Bachmeyer C, Lamarque G, Morariu R, et al. Visceral larva migrans mimicking lymphoma. Chest. 2003 Apr. 123(4):1296-7. [Medline].

Amir J, Harel L, Eidlitz-Markus T, Varsano I. Lymphedema as a presenting sign of toxocariasis. Infection. 1995 Nov-Dec. 23(6):389-90. [Medline].

Cruz AT, Franklin GY, Kaplan SL. Toxocariasis Causing Eosinophilic Ascites. Pediatr Infect Dis J. 2008 Apr 23. 27(6):563-4. [Medline].

Hamidou MA, Gueglio B, Cassagneau E, et al. Henoch-Schonlein purpura associated with Toxocara canis infection. J Rheumatol. 1999 Feb. 26(2):443-5. [Medline].

De Cock C, Lemaitre J, Deuvaert FE. Loeffler endomyocarditis: a clinical presentation as right ventricular tumor. J Heart Valve Dis. 1998 Nov. 7(6):668-71. [Medline].

Herry I, Philippe B, Hennequin C, et al. Acute life-threatening toxocaral tamponade. Chest. 1997 Dec. 112(6):1692-3. [Medline]. [Full Text].

Tobin EH, Zhang J, Maton B. Meningoencephalitis and visceral larva migrans in a woman with intense exposure to cats. Infect Dis Clin Pract. May, 2011. 19(3):221-2.

Salvador S, Ribeiro R, Winckler MI, Ohlweiler L, Riesgo R. Pediatric neurotoxocariasis with concomitant cerebral, cerebellar, and peripheral nervous system involvement: case report and review of the literature. J Pediatr (Rio J). 2010 Nov-Dec. 86(6):531-4. [Medline].

Centers for Disease Control and Prevention. Ocular toxocariasis–United States, 2009-2010. MMWR Morb Mortal Wkly Rep. 2011 Jun 10. 60(22):734-6. [Medline].

Ocular toxocariasis–United States, 2009-2010. MMWR Morb Mortal Wkly Rep. 2011 Jun 10. 60(22):734-6. [Medline].

Oski FA, et al. Ambulatory Pediatrics. Endophthalmitis. Principles and Practices of Pediatrics. 2nd edition. Philadelphia, PA: JB Lippincott; 1994. 888.

Stewart JM, Cubillan LD, Cunningham ET. Prevalence, clinical features, and causes of vision loss among patients with ocular toxocariasis. Retina. 2005 Dec. 25(8):1005-13. [Medline].

Woodhall D. Neglected Parasitic Infections: Toxocariasis. Centers for Disease Control and Prevention. Available at Accessed: February 4, 2015.

Abo-Shehada MN, Sharif L, el-Sukhon SN, et al. Seroprevalence of Toxocara canis antibodies in humans in northern Jordan. J Helminthol. 1992 Mar. 66(1):75-8. [Medline].

Agudelo C, Villareal E, Caceres E, et al. Human and dogs Toxocara canis infection in a poor neighborhood in Bogota. Mem Inst Oswaldo Cruz. 1990 Jan-Mar. 85(1):75-8. [Medline].

Akao N, Ohta N. Toxocariasis in Japan. Parasitol Int. 2007 Jun. 56(2):87-93. [Medline].

Altcheh J, Nallar M, Conca M, et al. [Toxocariasis: clinical and laboratory features in 54 patients]. An Pediatr (Barc). 2003 May. 58(5):425-31. [Medline].

American Academy of Pediatrics. Toxocariasis (Visceral Larva Migrans, Ocular Larva Migrans). Red Book: 2009 Report of the Committee on Infectious Diseases. 28th. Elk Grove Village, IL: American Academy of Pediatrics; 2009. 666-7.

Arango CA. Visceral larva migrans and the hypereosinophilia syndrome. South Med J. 1998 Sep. 91(9):882-3. [Medline].

Arpino C, Gattinara GC, Piergili D, Curatolo P. Toxocara infection and epilepsy in children: a case-control study. Epilepsia. 1990 Jan-Feb. 31(1):33-6. [Medline].

Ashwath ML, Robinson DR, Katner HP. A presumptive case of toxocariasis associated with eosinophilic pleural effusion: case report and literature review. Am J Trop Med Hyg. 2004 Dec. 71(6):764. [Medline]. [Full Text].

Toxocariasis. Spector JM, Gibson TE. Atlas of Pediatrics in the Tropics and Resource-Limited Settings. Elk Grove Village, IL: American Academy of Pediatrics; 2009. 249-251.

Baldisserotto M, Conchin CF, Soares Mda G, et al. Ultrasound findings in children with toxocariasis: report on 18 cases. Pediatr Radiol. 1999 May. 29(5):316-9. [Medline].

Bass JL, Mehta KA, Glickman LT, et al. Asymptomatic toxocariasis in children. A prospective study and treatment trial. Clin Pediatr (Phila). 1987 Sep. 26(9):441-6. [Medline].

Bede O, Szénási Z, Danka J, Gyurkovits K, Nagy D. Toxocariasis associated with chronic cough in childhood: a longitudinal study in Hungary. J Helminthol. 2008 Dec. 82(4):357-63. [Medline].

Beiran I, Cochavi O, Miller B. “Silent” ocular toxocariasis. Eur J Ophthalmol. 1998 Jul-Sep. 8(3):195-6. [Medline].

Buijs J, Borsboom G, van Gemund JJ, et al. Toxocara seroprevalence in 5-year-old elementary schoolchildren: relation with allergic asthma. Am J Epidemiol. 1994 Nov 1. 140(9):839-47. [Medline].

Carvalho EA, Rocha RL. Toxocariasis: visceral larva migrans in children. J Pediatr (Rio J). 2011 Mar-Apr. 87(2):100-10. [Medline].

Chang S, Lim JH, Choi D, et al. Hepatic visceral larva migrans of Toxocara canis: CT and sonographic findings. AJR Am J Roentgenol. 2006 Dec. 187(6):W622-9. [Medline].

Cianferoni A, Schneider L, Schantz PM, et al. Visceral larva migrans associated with earthworm ingestion: clinical evolution in an adolescent patient. Pediatrics. 2006 Feb. 117(2):e336-9. [Medline].

Cilla G, Perez-Trallero E, Gutierrez C, et al. Seroprevalence of Toxocara infection in middle-class and disadvantaged children in northern Spain (Gipuzkoa, Basque Country). Eur J Epidemiol. 1996 Oct. 12(5):541-3. [Medline].

Dauriac-Le Masson V, Chochon F, Demeret S, Pierrot-Deseilligny C. Toxocara canis meningomyelitis. J Neurol. 2005 Oct. 252(10):1267-8. [Medline].

Despommier D. Toxocariasis: clinical aspects, epidemiology, medical ecology, and molecular aspects. Clin Microbiol Rev. 2003 Apr. 16(2):265-72. [Medline].

Eberhard ML, Alfano E. Adult Toxocara cati infections in U.S. children: report of four cases. Am J Trop Med Hyg. 1998 Sep. 59(3):404-6. [Medline]. [Full Text].

Eberhardt O, Bialek R, Nagele T, Dichgans J. Eosinophilic meningomyelitis in toxocariasis: case report and review of the literature. Clin Neurol Neurosurg. 2005 Aug. 107(5):432-8. [Medline].

Elefant GR, Shimizu SH, Sanchez MC, et al. A serological follow-up of toxocariasis patients after chemotherapy based on the detection of IgG, IgA, and IgE antibodies by enzyme-linked immunosorbent assay. J Clin Lab Anal. 20(4):164-72. [Medline].

Fenoy S, Cuellar C, Guillen JL. Serological evidence of toxocariasis in patients from Spain with a clinical suspicion of visceral larva migrans. J Helminthol. 1997 Mar. 71(1):9-12. [Medline].

Fenoy S, Cuellar C, Guillen JL. Seroprevalence of toxocariasis in children and adults in Madrid and Tenerife, Spain. J Helminthol. 1996 Jun. 70(2):109-13. [Medline].

Fortenberry JD, Kenney RD, Younger J. Visceral larva migrans producing static encephalopathy in an infant. Pediatr Infect Dis J. 1991 May. 10(5):403-6. [Medline].

Frazier M, Anderson ML, Sophocleous S. Treatment of ocular toxocariasis with albendezole: a case report. Optometry. 2009 Apr. 80(4):175-80. [Medline].

Gavignet B, Piarroux R, Aubin F, Millon L, Humbert P. Cutaneous manifestations of human toxocariasis. J Am Acad Dermatol. 2008 Dec. 59(6):1031-42. [Medline].

Glickman LT, Schantz PM. Epidemiology and pathogenesis of zoonotic toxocariasis. Epidemiol Rev. 1981. 3:230-50. [Medline].

Good B, Holland CV, Taylor MR, et al. Ocular toxocariasis in schoolchildren. Clin Infect Dis. 2004 Jul 15. 39(2):173-8. [Medline].

Gotistein B, Piarroux R. Current trends in tissue-affecting helminths. Parasite. 2008 Sep. 15(3):291-8. [Medline].

Gould IM, Newell S, Green SH, George RH. Toxocariasis and eosinophilic meningitis. Br Med J (Clin Res Ed). 1985 Nov 2. 291(6504):1239-40. [Medline].

Graeff-Teixeira C, da Silva AC, Yoshimura K. Update on eosinophilic meningoencephalitis and its clinical relevance. Clin Microbiol Rev. 2009 Apr. 22(2):322-48, Table of Contents. [Medline].

Guneratne R, Mendis D, Bandara T, Fernando SD. Toxoplasma, toxocara and tuberculosis co-infection in a four year old child. BMC Pediatr. 2011 May 26. 11:44. [Medline]. [Full Text].

Havasiova K, Dubinsky P, Stefancikova A. A seroepidemiological study of human Toxocara infection in the Slovak Republic. J Helminthol. 1993 Dec. 67(4):291-6. [Medline].

Hayashi K, Tahara H, Yamashita K, et al. Hepatic imaging studies on patients with visceral larva migrans due to probable Ascaris suum infection. Abdom Imaging. 1999 Sep-Oct. 24(5):465-9. [Medline].

Heldrich FJ, Garg PP. Eosinophilic meningitis. Md Med J. 1988 Feb. 37(2):138-40. [Medline].

Hill IR, Denham DA, Scholtz CL. Toxocara canis larvae in the brain of a British child. Trans R Soc Trop Med Hyg. 1985. 79(3):351-4. [Medline].

Humbert P, Niezborala M, Salembier R, et al. Skin manifestations associated with toxocariasis: a case-control study. Dermatology. 2000. 201(3):230-4. [Medline].

Iddawela RD, Rajapakse RP, Perera NA, Agatsuma T. Characterization of a Toxocara canis species-specific excretory-secretory antigen (TcES-57) and development of a double sandwich ELISA for diagnosis of visceral larva migrans. Korean J Parasitol. 2007 Mar. 45(1):19-26. [Medline].

Inan M, Sakru N, Vatansever U, Bilgi S. Visceral larva migrans presenting as acute abdomen in a child. J Pediatr Surg. 41(3):e7-9. [Medline].

Inatomi Y, Murakami T, Tokunaga M, et al. Encephalopathy caused by visceral larva migrans due to Ascaris suum. J Neurol Sci. 1999 Apr 1. 164(2):195-9. [Medline].

Jain R, Sawhney S, Bhargava DK, et al. Hepatic granulomas due to visceral larva migrans in adults: appearance on US and MRI. Abdom Imaging. 1994 May-Jun. 19(3):253-6. [Medline].

Jeanfaivre T, Cimon B, Tolstuchow N, et al. Pleural effusion and toxocariasis. Thorax. 1996 Jan. 51(1):106-7. [Medline].

Kaushik SP, Hurwitz M, McDonald C, Pavli P. Toxocara canis infection and granulomatous hepatitis. Am J Gastroenterol. 1997 Jul. 92(7):1223-5. [Medline].

Kayes SG. Human toxocariasis and the visceral larva migrans syndrome: correlative immunopathology. Chem Immunol. 1997. 66:99-124. [Medline].

Kraus A, Valencia X, Cabral AR, de la Vega G. Visceral larva migrans mimicking rheumatic diseases. J Rheumatol. 1995 Mar. 22(3):497-500. [Medline].

Krcmery V Jr, Gould I, Sobota K, Spanik S. Two cases of disseminated toxocariasis in compromised hosts successfully treated with mebendazole. Chemotherapy. 1992. 38(5):367-8. [Medline].

Kumar J, Kimm J. MR in Toxocara canis myelopathy. AJNR Am J Neuroradiol. 1994 Nov. 15(10):1918-20. [Medline].

Lassmann B, Tsigrelis C, Virk A. 33-year-old woman with marked eosinophilia. Mayo Clin Proc. 2007 Jan. 82(1):103-6. [Medline].

Li MW, Lin RQ, Song HQ, Wu XY, Zhu XQ. The complete mitochondrial genomes for three Toxocara species of human and animal health significance. BMC Genomics. 2008 May 16. 9:224. [Medline].

Lim JH. Toxocariasis of the liver: visceral larva migrans. Abdom Imaging. 2008 Mar-Apr. 33(2):151-6. [Medline].

Ljungstrom I. Toxocara canis. Akuffo H, Linder E, Ljungstrom I, Wahlgren M. Parasites of the Colder Climates. London and New York: Taylor & Francis; 2003. 187-194.

Magnaval JF, Galindo V, Glickman LT, Clanet M. Human Toxocara infection of the central nervous system and neurological disorders: a case-control study. Parasitology. 1997 Nov. 115(Pt 5):537-43. [Medline].

Matos M de F, Militao DN, Brum MA, et al. Presence of anti-Toxocara antibodies in children selected at Hospital Universitario, Campo Grande, MS, Brazil. Rev Inst Med Trop Sao Paulo. 1997 Jan-Feb. 39(1):49-50. [Medline].

Matsuki Y, Fujii T, Nakamura-Uchiyama F, et al. Toxocariasis presenting with multiple effusions in the pericardial space, thoracic cavity, and Morrison’s pouch. Intern Med. 2007. 46(12):913-4. [Medline].

Mikhael NZ, Montpetit VJ, Orizaga M, et al. Toxocara canis infestation with encephalitis. Can J Neurol Sci. 1974 May. 1(2):114-20. [Medline].

Mimoso MG, Pereira MC, Estevao MH, et al. Eosinophilic meningoencephalitis due to Toxocara canis. Eur J Pediatr. 1993 Sep. 152(9):783-4. [Medline].

Moiyadi A, Mahadevan A, Anandh B, et al. Visceral larva migrans presenting as multiple intracranial and intraspinal abscesses. Neuropathology. 2007 Aug. 27(4):371-4. [Medline].

Monsel G, Caumes E. Recent developments in dermatological syndromes in returning travelers. Curr Opin Infect Dis. 2008 Oct. 21(5):495-9. [Medline].

Montalvo AM, Espino AM, Escalante G, Finlay CM. [Study of the seroprevalence of toxocariasis in an infantile population in the City of Havana]. Rev Cubana Med Trop. 1994. 46(3):156-8. [Medline].

Moreira-Silva SF, Leao ME, Mendonca HF, Pereira FE. Prevalence of anti-Toxocara antibodies in a random sample of inpatients at a children’s hospital in Vitoria, Espirito Santo, Brazil. Rev Inst Med Trop Sao Paulo. 1998 Jul-Aug. 40(4):259-61. [Medline].

Murray MG, Bahna SL. Allergy consult for eosinophilia in an infant. Allergy Asthma Proc. 2012 Jul-Aug. 33(4):370-3. [Medline].

Nathwani D, Laing RB, Currie PF. Covert toxocariasis–a cause of recurrent abdominal pain in childhood. Br J Clin Pract. 1992 Winter. 46(4):271. [Medline].

Nelson S, Greene T, Ernhart CB. Toxocara canis infection in preschool age children: risk factors and the cognitive development of preschool children. Neurotoxicol Teratol. 1996 Mar-Apr. 18(2):167-74. [Medline].

Ota KV, Dimaras H, Héon E, Babyn PS, Yau YC, Read S, et al. Toxocariasis mimicking liver, lung, and spinal cord metastases from retinoblastoma. Pediatr Infect Dis J. 2009 Mar. 28(3):252-4. [Medline].

Oteifa NM, Moustafa MA, Elgozamy BM. Toxocariasis as a possible cause of allergic diseases in children. J Egypt Soc Parasitol. 1998 Aug. 28(2):365-72. [Medline].

Patel H, Goldstein D. Pediatric uveitis. Pediatr Clin North Am. 2003 Feb. 50(1):125-36. [Medline].

Petithory JC. [Immunologic diagnosis of ocular larva migrans syndrome]. Ophtalmologie. 1990 May-Jun. 4(3):298-300. [Medline].

Rai SK, Uga S, Ono K, et al. Seroepidemiological study of Toxocara infection in Nepal. Southeast Asian J Trop Med Public Health. 1996 Jun. 27(2):286-90. [Medline].

Rayes AA, Lambertucci JR. Visceral larva migrans and pyogenic liver abscess. Am J Gastroenterol. 1999 Apr. 94(4):1116. [Medline].

Reilly A, Becker J, Meyer J, Rackoff W. Hypereosinophilia [clinical conference]. Med Pediatr Oncol. 1992. 20(3):232-9. [Medline].

Roig J, Romeu J, Riera C, et al. Acute eosinophilic pneumonia due to toxocariasis with bronchoalveolar lavage findings. Chest. 1992 Jul. 102(1):294-6. [Medline].

Roldán WH, Espinoza YA. Evaluation of an enzyme-linked immunoelectrotransfer blot test for the confirmatory serodiagnosis of human toxocariasis. Mem Inst Oswaldo Cruz. 2009 May. 104(3):411-8. [Medline].

Romeu J, Roig J, Bada JL, et al. Adult human toxocariasis acquired by eating raw snails. J Infect Dis. 1991 Aug. 164(2):438. [Medline].

Sabrosa NA, de Souza EC. Nematode infections of the eye: toxocariasis and diffuse unilateral subacute neuroretinitis. Curr Opin Ophthalmol. 2001 Dec. 12(6):450-4. [Medline].

Sabrosa NA, Zajdenweber M. Nematode infections of the eye: toxocariasis, onchocerciasis, diffuse unilateral subacute neuroretinitis, and cysticercosis. Ophthalmol Clin North Am. 2002 Sep. 15(3):351-6. [Medline].

Sakai S, Shida Y, Takahashi N, et al. Pulmonary lesions associated with visceral larva migrans due to Ascaris suum or Toxocara canis: imaging of six cases. AJR Am J Roentgenol. 186(6):1697-702. [Medline].

Sane AC, Barber BA. Pulmonary nodules due to Toxocara canis infection in an immunocompetent adult. South Med J. 1997 Jan. 90(1):78-9. [Medline].

Saporito L, Scarlata F, Colomba C, Infurnari L, Giordano S, Titone L. Human toxocariasis: a report of nine cases. Acta Paediatr. 2008 Sep. 97(9):1301-2. [Medline].

Sharkey JA, McKay PS. Ocular toxocariasis in a patient with repeatedly negative ELISA titre to Toxocara canis. Br J Ophthalmol. 1993 Apr. 77(4):253-4. [Medline].

Small KW, McCuen BW 2d, de Juan E Jr, Machemer R. Surgical management of retinal traction caused by toxocariasis. Am J Ophthalmol. 1989 Jul 15. 108(1):10-4. [Medline].

Sturchler D, Schubarth P, Gualzata M, et al. Thiabendazole vs. albendazole in treatment of toxocariasis: a clinical trial. Ann Trop Med Parasitol. 1989 Oct. 83(5):473-8. [Medline].

Szczepanski T, Sonta-Jakimczyk D, Janik-Moszant A, Olejnik I. Generalized lymphadenopathy as initial presentation of toxocariasis in a seven-year-old boy. Pediatr Infect Dis J. 1996 Aug. 15(8):717-8. [Medline].

Taylor MR, Keane CT, O’Connor P, Mulvihill E, Holland C. The expanded spectrum of toxocaral disease. Lancet. 1988 Mar 26. 1(8587):692-5. [Medline].

Taylor MR, O’Connor P, Hinson AR, Smith HV. Toxocara titres in maternal and cord blood. J Infect. 1996 May. 32(3):231-3. [Medline].

Torgerson PR, Rosenheim K, Tanner I, Ziadinov I, Grimm F, Brunner M, et al. Echinococcosis, toxocarosis and toxoplasmosis screening in a rural community in eastern Kazakhstan. Trop Med Int Health. 2009 Mar. 14(3):341-8. [Medline].

Uhlikova M, Hubner J. Seroprevalence of Toxocara canis infection in Czech Republic. Cent Eur J Public Health. 1998 Aug. 6(3):195-8. [Medline].

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

Villano M, Cerillo A, Narciso N, et al. A rare case of Toxocara canis arachnoidea. J Neurosurg Sci. 1992 Jan-Mar. 36(1):67-9. [Medline].

Walker MD, Zunt JR. Neuroparasitic infections: nematodes. Semin Neurol. 2005 Sep. 25(3):252-61. [Medline].

Walsh SS, Robson WJ, Hart CA. Acute transient myositis due to Toxocara. Arch Dis Child. 1988 Sep. 63(9):1087-8. [Medline].

Wells DL. Public understanding of toxocariasis. Public Health. 2007 Mar. 121(3):187-8. [Medline].

Wisniewska-Ligier M, Wozniakowska-Gesicka T, Sobolewska-Dryjanska J, Markiewicz-Józwiak A, Wieczorek M. Analysis of the course and treatment of toxocariasis in children-a long-term observation. Parasitol Res. 2012 Jun. 110(6):2363-71. [Medline]. [Full Text].

Wolfrom E, Chene G, Boisseau H, et al. Chronic urticaria and Toxocara canis. Lancet. 1995 Jan 21. 345(8943):196. [Medline].

Xinou E, Lefkopoulos A, Gelagoti M, et al. CT and MR imaging findings in cerebral toxocaral disease. AJNR Am J Neuroradiol. 2003 Apr. 24(4):714-8. [Medline].

Zachariah SB, Zachariah B, Varghese R. Neuroimaging studies of cerebral “visceral larva migrans” syndrome. J Neuroimaging. 1994 Jan. 4(1):39-40. [Medline].

Zygulska-Mach H, Krukar-Baster K, Ziobrowski S. Ocular toxocariasis in children and youth. Doc Ophthalmol. 1993. 84(2):145-54. [Medline].

Germaine L Defendi, MD, MS, FAAP Associate Clinical Professor, Department of Pediatrics, Olive View-UCLA Medical Center

Germaine L Defendi, MD, MS, FAAP is a member of the following medical societies: American Academy of Pediatrics

Disclosure: Nothing to disclose.

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Russell W Steele, MD Clinical Professor, Tulane University School of Medicine; Staff Physician, Ochsner Clinic Foundation

Russell W Steele, MD is a member of the following medical societies: American Academy of Pediatrics, American Association of Immunologists, American Pediatric Society, American Society for Microbiology, Infectious Diseases Society of America, Louisiana State Medical Society, Pediatric Infectious Diseases Society, Society for Pediatric Research, Southern Medical Association

Disclosure: Nothing to disclose.

Ashir Kumar, MD, MBBS FAAP, Professor Emeritus, Department of Pediatrics and Human Development, Michigan State University College of Human Medicine

Ashir Kumar, MD, MBBS is a member of the following medical societies: Infectious Diseases Society of America, American Association of Physicians of Indian Origin

Disclosure: Nothing to disclose.

Leslie L Barton, MD Professor Emerita of Pediatrics, University of Arizona College of Medicine

Leslie L Barton, MD is a member of the following medical societies: American Academy of Pediatrics, Association of Pediatric Program Directors, Infectious Diseases Society of America, and Pediatric Infectious Diseases Society

Disclosure: Nothing to disclose.

Marcelo Laufer, MD Attending Physician, Division of Pediatric Infectious Diseases, Miami Children’s Hospital

Marcelo Laufer, MD is a member of the following medical societies: American Academy of Pediatrics and Pediatric Infectious Diseases Society

Disclosure: Nothing to disclose.

Pediatric Toxocariasis

Research & References of Pediatric Toxocariasis|A&C Accounting And Tax Services