Age / Sex : 53 / M

Chief complaint :

tingling sensation, left arm (O: 2WA)

What is your diagnosis?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).

Courtesy : Kang Woo Young, Chungbuk National University Hospital

Discussion

Answer:  

spinal visceral larva migrans of Toxocara canis

Findings:

T2-weighted sagittal and axial images show patchy high signal intensity and swelling of spinal cord at C5 level. Postcontrast T1-weighted sagittal and axial images show focal nodular enhancement in the left posterolateral segment of spinal cord at C5 level.

Toxocariasis (ELISA, IgG antibody): positive.

CBC 5,070-15.4-43K (Eosinophil: 4.2%, normal range).

Differential Diagnosis:

spinal visceral larva migrans of Toxocara canis

nontumorous myelopathy such as transeverse myelitis

Discussion:

Toxocara canis is a parasite commonly found in dogs. It can infect humans when soil contaminated with embryonated eggs, or raw liver or meat containing its larvae, is ingested. Ingested larvae penetrate the host tissues using the systemic circulation and trigger eosinophilia and hyper-IgE-emia by inducing the immune-mediated hypersensitivity reaction. Myelopathy is secondary to hematogenous infestation of the spinal cord with visceral larva migrans. There may be migration from pulmonary lesions.

The diagnosis of toxocariasis relies on the detection of antibodies directed against the larval excretory-secretory antigens. The most commonly used immunodiagnostic technique is ELISA, with a test sensitivity ranging between 73% and 90%.

Typical MR findings are single lesion, focal nodular enhancement on posterior or posterolateral segment of spinal cord, relatively short segmental involvement of T2 hyperintensity with mild cord swelling and migration of lesion. In addition, the reluctant response to the treatment may be characteristic of spinal visceral larva migrans of Toxocara canis.

Albendazole treatment, with or without steroids, improved the patients’ symptoms and the MRI findings.

References:

Lee IH, Kim ST, Oh DK, et al. MRI findings of spinal visceral larva migrans of Toxocara canis. European journal of radiology. 2010;75(2):236-40.

Jabbour RA, Kanj SS, Sawaya RA, Awar GN, Hourani MH, Atweh SF. Toxocara canis myelitis: clinical features, magnetic resonance imaging (MRI) findings, and treatment outcome in 17 patients. Medicine. 2011;90(5):337-43

Park KH, Kim YS, Kim SK, et al. Toxocara canis-Associated Myelitis with Eosinophilic Pneumonia. Experimental neurobiology. 2016;25(3):139-4