Rapid in‐house method of CSF analysis utilising sedimentation direct from the spinal needle

Abstract

Objectives To establish the utility of a novel in‐house method of CSF analysis using sedimentation cytology direct from the spinal needle for the detection of laboratory‐defined pleocytosis. Materials and Methods In dogs and cats undergoing routine CSF analysis for investigation of neurological signs, an additional preparation was made at the patient's side by inverting the spinal needle on a slide and sedimenting for at least 1 hour. Nucleated cellularity and differential counts were assessed and compared with “gold‐standard” analysis. Variability of cell counts between observers and within slides using the new method was evaluated to optimise the procedure. Results Using a ×50 objective, at least 10 fields and an average of more than five cells per field were considered appropriate guidelines to achieve correct classification of samples (normal or pleocytosis). The new method had high sensitivity (89%) and specificity (100%) for the detection of laboratory‐defined pleocytosis. Agreement on the type of pleocytosis was good. Clinical Significance Clinically useful information can be obtained from CSF samples in a patient‐side setting without additional equipment. This technique may be of benefit if little fluid is available or if logistical constraints limit the availability of rapid specialist results.

Polysystemic autoimmune disease in a Cocker Spaniel with neurological and cardiac manifestations

“…Secondary assessment with rapid inhouse method of CSF analysis utilising direct sedimentation from the spinal needle was used. This documented an average of 5.4 non-degenerate neutrophils per x50 high power field, consistent with neutrophilic pleocytosis (89% sensitivity, 100% specificity), 8 despite mild haemodilution of the samples.…”

Evaluation of a Manual Cytocentrifuge versus the Standard Automated Cytocentrifuge in the Analysis of Canine Cerebrospinal Fluid: A Case Series of 55 Dogs

“…Many of these methods are complicated, making their use in clinical practice difficult [9]. Various inexpensive cell concentration techniques have been proposed, including membrane filtration [10], sedimentation chambers [3,[9][10][11], the sedimentation of CSF direct from the needle [12], the line smear technique [13] and manual cytocentrifugation [14]. The most common techniques are cytocentrifugation and sedimentation [3,[9][10][11].…”