Canine C-Reactive Protein Measurements in Cerebrospinal Fluid by a Time-Resolved Immunofluorimetric Assay

Abstract

Abstract. In the current study, the quantification of C-reactive protein (CRP) in cerebrospinal fluid (CSF) of dogs using an adapted time-resolved immunofluorimetric assay (TR-IFMA) was investigated, as well as whether the assay could be used to detect the range of CRP concentrations found in different clinical situations. Intra-and interassay coefficients of variation were below 15% in all cases. The TR-IFMA measured the CRP values in a proportional and linear manner (r 5 0.99); also CRP concentrations measured in CSF and in serum were significantly correlated (r 5 0.80, P 5 0.003). The limit of detection of the method was 7.1 3 10 26 mg/l. The assay was able to detect differences in CRP concentrations in CSF of dogs with inflammatory disorders compared with dogs with spinal cord compression or idiopathic epilepsy. In conclusion, TR-IFMA constitutes a very sensitive, precise, and accurate method for the measurement of CRP concentrations in CSF.

Fibrinolytic Activity in Cerebrospinal Fluid of Dogs with Different Neurological Disorders

“…For this reason, CRP was also measured in CSF and blood samples of the same patients to assess the relationship between inflammation and coagulation. In our study, CRP was detected in 182/183 CSF samples, which demonstrates the high sensitivity of the TR‐IFMA method compared with that of other techniques previously reported . Our study showed that CRP is present in the CSF of healthy dogs, a fact that has not been previously reported.…”

“…C‐reactive protein was measured in blood and CSF samples, as previously described, using a TR‐IFMA method . k Results were reported in mg/L.…”

“…Time‐resolved immunofluorimetric assay (TR‐IFMA) has been recently validated in canine CSF samples to measure CRP concentrations. TR‐IMFA has been shown to have a high sensitivity, so very small amounts of CRP can be detected in canine CSF samples …”

Utility of C‐reactive protein and serum amyloid A in the diagnosis of equine protozoal myeloencephalitis

“…subarachnoid hemorrhage6 or vasculitis due to sepsis17); intrathecal production of CRP18 and disruption of glymphatic circulation may also contribute to a lesser extent 19. Even when the blood–brain barrier is intact CRP level in the CSF is directly related to serum CRP because this protein flows from blood into the cerebrospinal space,20 but determination of a CRP index along with IgG index has been proposed in cases of canine Steroid Responsive Meningitis‐Arteritis (SRMA)6 and may also be helpful in cases of blood–brain barrier disruption in equine neurological disease.…”

“…No studies have evaluated the stability of CRP in frozen equine serum and spinal fluid, but human serum has been stored up to 11 years at −80°C without any significant change 24. Canine CRP studies have also routinely stored serum and CSF frozen (−20°C) prior to assay 6, 7, 20…”