“Cytology of the normal and abnormal choroid plexi in selected domestic mammals, wildlife species, and man.”

Avina et al.

JVDI 2004.

Four different morphologic cell types were consistently found in all the species studied. The first 3 types were arbitrarily named alpha (with deeply basophilic cytoplasm), beta (with neutral to weakly acidophilic cytoplasm), and gamma or vesicle-bearing cells. The third type, gamma, was a cell bearing unique inclusions (vesicles) filled with many tiny light tan to pale pink granules. The fourth type was the Kolmer cell found in very low numbers. Immature lymphocytes were found in all of 3 newborn foals, in 1 pig, and in the only stillborn calf and deer studied. The results suggest that the choroid plexi contain more than 1 epithelial cell type and that knowledge of their morphology is far from complete because other unusual cells and structures are also present in small numbers. Imprints are excellent for studying the choroid plexi, especially for tiny changes that are too subtle to be seen in hematoxylin and eosin sections.

“Inflammatory cerebrospinal fluid analysis in cats: clinical diagnosis and outcome.”

Singh et al.

JFMS 2005.

The medical records of 62 cats with clinical signs of central nervous system disease and accompanying inflammatory cerebrospinal fluid (CSF) analysis were examined retrospectively to determine if signalment, clinical signs, CSF analysis and ancillary testing could accurately predict the type of central nervous system disease that was present. An inflammatory CSF was defined as one in which a total nucleated cell count was greater than 5 cells/ml or one in which the total nucleated cell count was normal but the nucleated cell differential count was abnormal. Sex, degree of CSF inflammation, neuroanatomical location and systemic signs provided little contributory information to the final diagnosis. In 63% of the cases a presumptive diagnosis could be made based on a combination of clinical signs, clinicopathological data and ancillary diagnostic tests. CSF analysis alone was useful only in the diagnosis of cats with feline infectious peritonitis, Cryptococcus species infection, lymphoma and trauma. Overall, despite extensive diagnostic evaluation, a specific diagnosis could not be made in 37% of cats. The prognosis for cats with inflammatory CSF was poor with 77% of cats surviving less than 1 year.

“Composition of cerebrospinal fluid in clinically normal adult ferrets.”

Platt et al.

AJVR 2005.

Results—Total WBC counts (range, 0 to 8 cells/μL; mean, 1.59 cells/μL) in CSF of ferrets were similar to reference range values obtained for CSF from other species. Twenty-seven CSF samples had < 100 RBCs/μL (mean, 20.3 RBCs/μL). A small but significant effect of blood contamination on WBC counts was found between the 27 CSF samples with < 100 RBCs/μL and the remaining samples. Protein concentrations in CSF of ferrets (range, 28.0 to 68.0 mg/dL; mean, 31.4 mg/dL) were higher than has been reported for the CSF of dogs and cats. A significant effect of blood contamination on the CSF protein concentration was not found.

“An inexpensive sedimentation chamber for the preparation of cytologic specimens of cerebrospinal fluid.”

Avina et al.

JVDI 2005.

“High Resolution Protein Electrophoresis of 100 Paired Canine Cerebrospinal Fluid and Serum.”

Behr et al.

JVIM 2006.

This study was performed to investigate the diagnostic relevance of cerebrospinal fluid (CSF) high resolution electrophoresis. The laboratory technique was applied to 100 paired samples of canine CSF and serum, with paired samples tested during the same analytical run, as recommended in human medicine. Ninety four of the dogs had a neurological disease and 6 healthy dogs served as a control group. A strong linear correlation between CSF total protein concentration and the albumin quota (AQ) was found in the control group and in the inflammatory (infectious or noninfectious), neoplastic, and miscellaneous groups: AQ 5 0.015 CSF total protein 2 0.102, r 5 0.990. This correlation suggests that an increased CSF total protein concentration can be an indicator of blood brain barrier dysfunction. The highest median AQ value was found in the aseptic suppurative meningitis group, but no statistical differences were found between this and the other groups. The AQ, calculated with this technique, did not provide any additional information. Moreover, although unexpected, the electrophoretic profiles were not characteristic of any particular disease. In conclusion, this study did not confirm high resolution electrophoresis of paired CSF and serum samples to be a valuable ancillary diagnostic tool for canine neurological diseases.

*A high Ig index is usually consistent with an intrathecal Ig synthesis, whereas a high AQ is considered an indicator of BBB impairment