Aberrant extradural spinal migration of Spirocerca lupi: four dogs

Abstract

Spirocerca lupi is a nematode mainly affecting dogs but has been found in other animals, particularly carnivores. Anatomical areas of typical and aberrant migration vary. This report describes four cases of Spirocerca lupi causing neurological symptoms, similar to thoracolumbar disc syndrome, as a result of aberrant migration of the nematode into the spinal canal. In two of the cases, the nematode could be demonstrated intraoperatively. The third was discovered on post-mortem examination, while the fourth case displayed compelling evidence of Spirocerca lupi involvement. Surgical removal of the Spirocerca lupi nematode would be the treatment of choice in cases of spinal migration, with therapeutic and preventive treatment with doramectin instituted to treat remote sites and prevent re-infection. In areas endemic for spirocercosis, Spirocerca lupi should be considered as an important differential diagnosis in cases that are presented with clinical signs suggestive of a spinal cord lesion.

Nematode eggs observed in cytology of cerebrospinal fluid diagnostic for intramedullary Spirocerca lupi spinal cord migration

“…In the esophagus, they mature to adults, induce fibrous tissue nodule formation, sexually reproduce, and shed eggs into the esophageal lumen and the feces . Aberrant worm migration has been well‐documented and can occur in many other organs, including the spinal cord …”

“…Intramedullary spirocercosis results in dramatic clinical signs, including acute severe back pain, which is shortly followed by nonsymmetrical paraparesis or tetraparesis or paralysis. The neurologic manifestation depends on the location and extent of damage induced by migrating nematodes through the spinal cord . Such aberrant spinal cord migration is more often only tentatively diagnosed based on the typical presentation, which occurs mostly in large‐breed dogs, and the presence of CSF eosinophilic or mixed‐eosinophilic pleocytosis.…”

“…Such dogs may or may not have concurrent esophageal spirocercosis, aortic aneurysms, or thoracic spinal vertebral spondylosis and spondylitis, which is characteristic of typical spirocercosis cases . So far, the definitive diagnosis of spinal spirocercosis is made by postmortem gross and microscopic examinations, or can be found as an incidental finding during spinal cord surgery …”

Spirocerca lupi granulomatous pneumonia in two free-ranging maned wolves (Chrysocyon brachyurus) from central Brazil

“…16,21 Aberrant migration to the vertebral canal affecting spinal cord in dogs has only been rarely reported. 8,20 In dogs, S. lupi granulomatous lesions can frequently develop into sarcomas. 9,19 No neoplastic lesions were observed in either wolf from the current report.…”

The Efficacy of a Topically Applied Imidacloprid 10 % / Moxidectin 2.5 % Formulation (Advocate®, Advantage® Multi, Bayer) against Immature and Adult Spirocerca lupi Worms in Experimentally Infected Dogs

“…The aortic aneurysms, considered pathognomonic for S. lupi infections, are frequently the cause for acute death due to aortic rupture and fatal haemorrhage (Bailey 1963(Bailey , 1972. Subclinical infections aside, antemortal clinical signs in dogs infected with Spirocerca are varied and may include coughing, regurgitation, anorexia, weight loss, vomiting, dysphagia, salivation, inhalation pneumonia, paraparesis, back pain, melaena, anaemia and central nervous system involvement (Dvir et al 2001;Du Plessis et al 2007;van der Merwe et al 2008). A diagnosis of spirocercosis in the dog may be aided by the presence of various combinations of the above-mentioned symptoms as well as the presence of S. lupi eggs in the stool, demonstrated by a modified faecal flotation technique (Markovics and Medinski 1996), reported to increase the diagnostic sensitivity of the test.…”