Mariani, Christopher L.Christopher L.MarianiNye, Carolyn J.Carolyn J.NyeTokarz, Debra A.Debra A.TokarzGreen, LaurenLaurenGreenLau, JeanieJeanieLauZidan, NataliaNataliaZidanEarly, Peter J.Peter J.EarlyGuevar, Julien JeanJulien JeanGuevarMuñana, Karen R.Karen R.MuñanaOlby, Natasha J.Natasha J.OlbyMiles, SaritaSaritaMiles2024-09-022024-09-022019-11https://boris-portal.unibe.ch/handle/20.500.12422/37395BACKGROUND Cerebrospinal fluid (CSF) lactate is frequently used as a biomarker in humans with inflammatory central nervous system (CNS) disorders including bacterial meningitis and autoimmune disorders such as multiple sclerosis. HYPOTHESIS Cerebrospinal fluid lactate concentrations are increased in a subset of dogs with inflammatory CNS disorders. ANIMALS One hundred two client-owned dogs diagnosed with inflammatory CNS disease. METHODS Case series. Cases were identified both prospectively at the time of diagnosis and retrospectively by review of a CSF biorepository. Cerebrospinal fluid lactate was analyzed with a commercially available, handheld lactate monitor. Subcategories of inflammatory disease were created for comparison (eg, steroid-responsive meningitis arteritis, meningoencephalitis of unknown etiology). RESULTS Cerebrospinal fluid lactate concentrations were above reference range in 47% of dogs (median, 2.5 mmol/L; range, 1.0-11.7 mmol/L). There was no significant difference in lactate concentrations between disease subcategories (P = .48). Significant but weak correlations were noted between CSF lactate concentration and nucleated cell count (r = .33, P < .001), absolute large mononuclear cell count (r = .44, P < .001), absolute small mononuclear cell count (r = .39, P < .001), absolute neutrophil cell count (r = .24, P = .01), and protein (r = .44, P < .001). No correlation was found between CSF lactate concentration and CSF red blood cell count (P = .58). There was no significant association of CSF lactate concentration with survival (P = .27). CONCLUSIONS AND CLINICAL IMPORTANCE Cerebrospinal fluid lactate concentrations could serve as a rapid biomarker of inflammatory CNS disease in dogs.encanine encephalitis meningitis meningo meningoencephalitis myelitis600 - Technology::630 - Agriculturearticle10.7892/boris.1470973154974010.1111/jvim.15606