Results suggest that MR imaging may be helpful in the diagnosis and treatment of VD in dogs.

No abstract

The diagnosis of nemaline rod myopathy (NM) is based on the presence of numerous pathognomonic rods within a fresh frozen muscle biopsy specimen. Three forms of congenital NM have been described in humans, and rods have been found to occur in various other conditions. A similar myopathy was described in 1986 in a family of cats. In this report. we describe a case of congenital NM in a 10-month-old Border Collie, an adult-onset NM in an 1 I-year-old Schipperke, and 2 acquired myopathies with nemaline rods in adult dogs associated with hypothyroidism and Cushing's syndrome. Common clinical features included exercise intolerance, abnormal electromyography, and the presence of nemaline rods in fresh, frozen, and glutaraldehyde-fixed biopsies from proximal appendicular limb muscles. Staining of cryostat sections of muscle biopsy specimens by the modified Gomori trichrome technique disclosed numerous rod bodies that were localized to type 1 fibers by the histochemical adenosine triphosphatase reaction. Accumulation of rods also was demonstrated by electron microscopy in 2 of the cases with localized enlargement and streaming of Z lines. Documentation of NM in a young Border Collie and the adult-onset form in the Schipperke alerts clinicians to the existence of this disorder in these breeds.

The post-mortem diagnosis of lysosomal storage diseases can be confounded by the unavailability of suitable material. Here we report the diagnosis of GM1-gangliosidosis in a cross-bred dog, from which only formalin-fixed brain was available, by a combination of electron microscopy and the detection of elevated levels of GM1-ganglioside within the tissue using the novel technique of electrospray ionisation tandem mass spectrometry. Electron microscopic examination of ultrathin sections of resin-embedded tissue revealed cytoplasmic inclusions (membranous cytoplasmic and zebra bodies) in brain stem and cerebellar neurons that were characteristic of a gangliosidosis. Glycolipids were extracted from the fixed tissue and analysed by tandem mass spectrometry. Two major ions were detected, which corresponded to GM1 (d18:1-C18:0) and Gm1 (d20:1-C18:0). Their identity was confirmed by comparison of their fragmentation patterns with those of authentic standards. The concentration of GM1 was approximately sixfold higher on a wet weight basis than in the brain of a normal control dog, confirming the diagnosis of GM1-gangliosidosis.

No abstract

A mixed inflammatory cell pleocytosis was identified in a cytocentrifuged sample of cerebrospinal fluid (CSF) and diagnosis of histoplasmosis was made on the basis of finding Histoplasma capsulatum organisms within macrophages. This dog had disseminated histoplasmosis with multiple organ involvement including the central nervous system (CNS) and eye.