Cytological, immunocytochemical and biochemical cerebrospinal fluid investigations in selected central nervous system disorders of dogs.

Cerebrospinal fluid (CSF) obtained from 20 clinically healthy dogs and from 15 dogs affected by neurological disorders were examined for total and differential cell counts, immunocytochemistry for canine distemper virus antigen, total protein concentration and electrophoretic separation, and glucose and enzyme determination. Dogs affected by canine distemper showed an increase in macrophages, presence of specific inclusion bodies, and an increase in total protein concentration and gamma-globulin fraction. In bacterial meningoencephalomyelitis pleocytosis, increase of total proteins with special regard to high molecular weight proteins, elevated levels of lactate dehydrogenase (LDH), alterations of LDH isoenzyme profile, and decrease in glucose levels were detected; inflammatory disorders were more often characterized by an increase in LDH level, while in non-inflammatory disorders (hydrocephalus and spinal cord neoplasia) no variation in LDH levels was detected. Analysis of CSF in dogs appears relatively easy to perform and may help in establishing the condition of the blood-brain barrier as well as in the diagnosis of neurological disorders.