Feline Dysautonomia (The Key‐gaskell Syndrome): An Ultra Structural Study of Autonomic Ganglia and Nerves

Abstract

Recently a feline dysautonomia of unknown aetiology, the Key-Gaskell syndrome, has caused widespread morbidity in the UK. This report describes the ultrastructural appearances of the autonomic ganglia and axons of the sympathetic chain in this condition. Nuclei of affected neurones were eccentric and abnormally crenated. Nucleolar abnormalities such as increased electron density (due to loss of the intranucleolar vacuoles), nucleolar segregation and ring nucleoli were observed in a proportion of neurones. There was marked loss of ribosomes, both bound and unbound, and cisternae of the rough endoplasmic reticulum were distended with a floccular electron dense material. Numerous smooth-walled cisternae were also present and complex stacks of smooth semi-parallel membranes were observed, probably derived from the smooth endoplasmic reticulum or Golgi apparatus. No normal Golgi formations were seen. Frequent autophagic vacuoles and membranous dense bodies were present in some cells. Many unmyelinated fibres in the sympathetic chain were swollen and contained vesiculo-tubular profiles, disordered neurotubules and filaments and various degenerating membranous organelles. Myelinated fibres within the sympathetic chain were also degenerating. These studies indicate that the organelles involved with protein biosynthesis are severely affected by the disease.

Feline dysautonomia in the Midwestern United States: A retrospective study of nine cases

“…Dorsal root ganglia and the ganglia of cranial nerves may also be affected. Enteric and central nervous system lesions have been reported in cats, as well as in dogs and horses, with dysautonomia (Sharp et al 1984, Griffiths et al 1985, Pollin and Sullivan 1986, Prethus and Bjerkas 1987, Edney et al 1987, Pollin and Griffiths 1992, Longshore et al 1996, Schulze et al 1997, Harkin et al 2002. Two of the cats examined in this study had neuronal degeneration seen in the myenteric plexus.…”

“…However, definitive diagnosis of feline dysautonomia is based upon demonstration of characteristic histological lesions in the autonomic ganglia. Descriptions of the gross and microscopic pathology of dysautonomia have been extensively reviewed elsewhere (Sharp et al 1984, Griffiths et al 1985, Edney et al 1987, Pollin and Griffiths 1992. Generally, both parasympathetic and sympathetic ganglia are usually affected to the same degree, although disease chronicity may alter the pattern and degree of neuronal loss.…”

Abomasal Emptying Defect of Sheep may be an Acquired Form of Dysautonomia

“…7,9 Although usually sporadic, small outbreaks of grass sickness have occurred 23 and may even be associated with a similar disease in hares on the same premises. 3,23 Forms of dysautonomia also occur in dogs 12,15,24 and cats, 2,11,17,18 and there has been one report of an affected llama. 4 Both sporadic and familial forms of dysautonomia affect humans 20,25 and may occur more frequently in certain ethnic groups.…”

Prospects for vaccination against equine grass sickness

“…Dysautonomic diseases are also recognised in man, cats (Key and Gaskell 1982;Griffiths et al 1985), dogs (Berghaus et al 2001(Berghaus et al , 2002Harkin et al 2002) and hind-gut fermentors such as wild hares (Whitwell 1991;Griffiths and Whitwell 1993;Hahn et al 2001) and domestic and wild rabbits (Whitwell and Needham 1996). In all cases, the aetiology is unknown but pathological features are very similar.…”