What is your diagnosis? Cerebrospinal fluid from a dog

Abstract

A 6-year-old spayed female Boxer dog was presented to the Louisiana State University Veterinary Teaching Hospital with a 3-week history of ataxia, walking sideways, crossing over of limbs, and dragging her hind feet. She had a repair of her left cranial cruciate ligament approximately 4 months previously with uneventful recovery. There was no history of diarrhea or vomiting. Results of a CBC and urinalysis were unremarkable. The only abnormality noted on serum biochemical profile was mild hypercholesterolemia (296 mg/dL, reference interval [RI] 150-240 mg/dL). Cutaneous and mucosal lesions were not present. Age-related changes were seen on thoracic radiographs. Neurologic examination revealed severe ataxia, worse on the left side, and a left head tilt. She had delayed hopping in the forelimbs and fell when hopped in the rear. No abnormalities were observed on computed tomographic scan of the brain. Magnetic resonance imaging of the brain revealed a lesion involving approximately 50% of the left side of the pons and medulla and extending dorsally to the 4th ventricle. Cerebrospinal fluid (CSF) collected from the atlanto-occipital cistern revealed a total nucleated cell count of 2000/mL (RI o 5/mL) and a total protein of 1898 mg/dL (RI o 30 mg/dL). A cytocentrifuged preparation of CSF was stained with Wright-Giemsa and examined (Figure 1). Figure 1. Cytocentrifuged preparation of cerebrospinal fluid from a dog. Wright-Giemsa, Â 100 objective.

Disseminated protothecosis diagnosed by evaluation of CSF in a dog

“…To our knowledge, identification of organisms by cytologic examination of CSF has been reported previously only twice . Surprisingly, CSF changes are rarely described in cases of canine protothecosis despite the relatively frequent occurrence of neurologic signs . Eosinophilic pleocytosis has been reported previously in 3 cases (nucleated cell counts ranged 2000–6182/μL with 65–85% eosinophils), and in 2 of those dogs organisms were isolated by culture of CSF despite not being identified by cytologic examination of CSF .…”

“…They have thin non‐staining cell walls, basophilic granular cytoplasm, and small centrally placed nuclei and reproduce by endosporulation. To our knowledge, identification of organisms by cytologic examination of CSF has been reported previously only twice . Surprisingly, CSF changes are rarely described in cases of canine protothecosis despite the relatively frequent occurrence of neurologic signs .…”

“…16,18 Surprisingly, CSF changes are rarely described in cases of canine protothecosis despite the relatively frequent occurrence of neurologic signs. 6,8,16,18 Eosinophilic pleocytosis has been reported previously in 3 cases (nucleated cell counts ranged 2000-6182/lL with 65-85% eosinophils), 6,8,18 and in 2 of those dogs organisms were isolated by culture of CSF despite not being identified by cytologic examination of CSF. 6,8 In an additional dog with eosinophilic pleocytosis (49% eosinophils, but nucleated cell counts not reported), Prototheca organisms were identified on cytologic examination of CSF.…”

Use of posaconazole for treatment of disseminated protothecosis in a dog

“…Previous reports of CSF analysis in dogs with CNS protothecosis have described the presence of an eosinophilic pleocytosis (Gupta and others 2011, Lane and others 2012). Though eosinophils were present in increased numbers in the CSF in this case, the inflammation consisted predominantly of small and large lymphocytes, with the presence of atypical large granulated mononuclear cells.…”

The Central Nervous System

“…Eosinophilic CSF pleocytosis is rare. Sometimes, migrating internal parasites, such as Baylisascaris procyonis (Windsor et al, 2009) or Angiostrongylus cantonensis (Lunn et al, 2012), or infectious agents, such as Prototheca infection (Gupta et al, 2011;Lane et al, 2012), canine distemper virus infection, or rabies, may cause eosinophilic pleocytosis (Chrisman, 1992). 14-10A&B) and neosporosis or Cryptococcus (Windsor et al, 2009) infection.…”