Clinical Biochemistry of Domestic Animals (Sixth Edition) - UMK ...

VIII. Characteristics of CSF Associated with Specific Diseases
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neurons in the brain stem nuclei or degeneration of brain stem
white matter tracts. Inflammation is not evident. Lumbosacral
CSF from both animals was normal ( Morin et al. , 1994 ).
3 . Equine Motor Neuron Disease
The CSF of horses with this ( Loscher and Schwartz-
Porsche, 1986 ) disorder is either normal or has albuminocytological
dissociation ( Cummings et al. , 1990 ; Divers et al. ,
1994 ; Morin et al. , 1994 ). In a study of 28 cases ( Divers
et al. , 1994 ), 9 of 26 horses had elevated CSF protein. The
albumin quotient was abnormal in only 2 of 19 horses.
The IgG index was increased in 8 of 16 horses. The abnormalities
in total protein and IgG index did not appear to
be associated with the duration or severity of clinical signs.
The increased protein and IgG index in these horses suggest
that intrathecal immunoglobulin production occurs.
Blood-brain barrier damage and intrathecal IgG production
also occur in people with motor neuron disease ( Apostolski
et al. , 1991 ).
B . Idiopathic Diseases
1 . Granulomatous Meningoencephalomyelitis
The CSF associated with granulomatous meningoencephalomyelitis
(GME) is usually abnormal. The fluid may be
clear or hazy and is generally colorless. The total white
blood cell count is moderately to markedly elevated, as
is the total protein. The white blood cell differential is
variable, but typically lymphocytes predominate, with
monocytes/macrophages and neutrophils comprising the
remainder in about equal percentages ( Bailey and Higgins,
1986a ; Braund, 1994 ; Sarfaty et al. , 1986 ; Thomas and
Eger, 1989 ; Tipold, 1995 ). A 15% to 30% neutrophilic
component suggests GME, but the white blood cell differential
can range from 95% neutrophils ( Sorjonen, 1990 )
to 100% mononuclear cells. Plasma cells, cells undergoing
mitosis, and large, mononuclear cells with abundant
foamy cytoplasm are occasionally present ( Bailey
and Higgins, 1986a ; Braund, 1994 ). Lumbar fluid is also
abnormal, although it generally has fewer cells and less
protein than cerebellomedullary fluid ( Bailey and Higgins,
1986a ). Electrophoresis of CSF suggests blood-brain barrier
dysfunction is present in the acute stage of disease;
intrathecal IgG production with resolution of the barrier
dysfunction occurs in chronic disease ( Sorjonen, 1990 ).
The albumin quota is elevated ( Sorjonen, 1987 ), and the
IgG index is usually elevated ( Bichsel et al. , 1984b ; Tipold
et al. , 1993b, 1994 ). If barrier dysfunction is severe, with
marked transudation of protein, the IgG index may be normal
because the amount of intrathecally produced IgG is
small in comparison to the amount of transudated serum
IgG ( Bichsel et al. , 1984b ; Fishman, 1992 ).
2 . Necrotizing Encephalitis of Pug Dogs, Maltese Dogs,
and Yorkshire Terriers
A necrotizing encephalitis (NE) of unknown cause is recognized
in pug dogs ( Cordy and Holliday, 1989 ; de Lahunta,
1983 ), Maltese dogs ( Stalis et al. , 1995 ), and Yorkshire terriers
( Ducote et al. , 1999 ; Jull et al. , 1997 ; Kuwamura et al. ,
2002 ; Tipold et al. , 1993a ). The lesions are similar in each
breed, although the distribution of lesions in the pug and
Maltese dogs (large, diffuse, cerebral) is different from that
in the Yorkshire terriers (well-defined multifocal brain stem).
The CSF associated with the pug and Maltese dog diseases
has a moderate to marked, predominantly lymphocytic,
increased white blood cell count (although one Maltese had
62% neutrophils) and moderate to marked elevation in total
protein ( Bradley, 1991 ; Cordy and Holliday, 1989 ; Stalis
et al. , 1995 ). The CSF of the Yorkshire terriers has mild to
moderate increases in white blood cells and protein, with
a predominantly mononuclear differential count ( Ducote
et al. , 1999 ; Tipold, 1995 ; Tipold et al. , 1993a ). Seizures are
a consistent clinical sign for the pugs and the Maltese dogs
but not the Yorkshire terriers.
An autoantibody against canine astrocytes has been
detected in the CSF of dogs with NE ( Matsuki et al. , 2004 ;
Uchida et al. , 1999 ). This autoantibody, which recognizes
glial fibrillary acidic protein, has also been detected in
the CSF of dogs with GME and with intracranial tumors
( Matsuki et al. , 2004 ); therefore, it is not a specific finding
in dogs with NE. It is unknown if the presence of this
antibody is a primary or secondary phenomenon. Further
research is necessary to determine the clinical utility of the
presence of this autoantibody in CSF.
C . Immune-Mediated Diseases
1 . Acute Idiopathic Polyradiculoneuritis/Coonhound
Paralysis
Acute idiopathic polyradiculoneuritis is one of the most
common canine polyneuropathies, and coonhound paralysis
is the most common form. The disorder resembles Guillain-
Barre syndrome of people. In affected dogs, the classical
CSF abnormality is albuminocytological dissociation. The
abnormality is more obvious in lumbar CSF than in cerebellomedullary
CSF ( Cuddon, 1990 ; Cummings et al. ,
1982 ). The CSF IgG level and IgG index may also be
increased, indicating intrathecal immunoglobulin production
( Cuddon, 1990 ; Tipold et al. , 1993b ).
2 . Equine Cauda Equina Neuritis
This disease is thought to be an autoimmune polyneuritis.
The CSF of affected horses may be xanthochromic and
typically has a prominent, usually lymphocytic pleocytosis
(at least in the chronic stage) and moderately elevated