A retrospective case series of clinical signs in 28 Beagles with Lafora disease

Abstract

Background Clinical signs and their progression in Beagles with Lafora disease are poorly described. Objectives To describe clinical signs in Beagles with Lafora disease. Animals Twenty‐eight Beagles with Lafora disease confirmed by genetic testing or histopathology. Methods Retrospective multicenter case series. Data regarding signalment, clinical signs, diagnostic tests and treatment were retrieved from hospital data files. A questionnaire was sent to owners asking about neurological deficits, changes in cognitive functions, behavioral changes, response to treatment and survival time. Results Onset of clinical signs was 8.3 years (mean; range, 6.3‐13.3). All dogs had myoclonic episodes as an initial clinical sign with tonic‐clonic seizures in n = 11/28 (39%) and n = 12/28 (43%) later developing tonic‐clonic seizures. Deficits of coordination (n = 21/25; 84%), impaired vision (n = 15/26; 58%), and impaired hearing (n = 13/26; 50%) developed later. Mental decline was observed as loss of house training (urination; n = 8/25; 32%), difficulties performing learned tasks (n = 9/25; 36%), and difficulties learning new tasks (n = 7/23; 30%). Common behavioral changes were: increased photosensitivity (n = 20/26; 77%), staring into space (n = 16/25; 64%), reduced stress resistance (n = 15/26; 58%), increased noise sensitivity (n = 14/26; 54%), and separation anxiety (n = 11/25; 44%). Twenty‐one dogs were alive (median age 11.9 years; range, 9.8‐18.6), and 7 dogs were dead (mean age 12.1 years; SD: 1.3; range, 10.5‐12.6) at time of writing. Conclusions and Clinical Importance Lafora disease in Beagles causes significant behavioral changes, and mental decline as well as neurological deficits in addition to myoclonic episodes and generalized tonic‐clonic seizures. Nevertheless, a relatively normal life span can be expected.

Polyglucosan body disease in an aged chimpanzee (Pan troglodytes)

“…Various types of PGBs have been identified in diverse animal species 3,24–44,69,70 . Although they share some ultrastructural and compositional features with PGBs in humans, PGBs in non‐human species can also differ in important ways 1 .…”

“…Hence, it is sometimes uncertain whether the PGBs in non‐human species correspond to corpora amylacea or Lafora‐type bodies or whether they are different lesions altogether. In some instances, the PGBs were not associated with detectable clinical disease in animals, although in other cases there was a clear link to neurologic dysfunction, e.g 6,24–26,33,34,40,44,69,70 …”

“…Various types of PGBs have been identified in diverse animal species. 3,69,70 Although they share some ultrastructural and compositional features with PGBs in humans, PGBs in non-human species can also differ in important ways. 1 Hence, it is sometimes uncertain whether the PGBs in non-human species correspond to corpora amylacea or Lafora-type bodies or whether they are different lesions altogether.…”

Dogs as a Natural Animal Model of Epilepsy

“…In addition to Beagles, PME has been described in several other breeds including the Basset hound, Chihuahua, French Bulldog, Pointer, Miniature Poodle, Miniature Dachshund, and Welsh Corgi (49,265). More recently, PME in Beagle dogs has been characterized in more detail (266). In a large series of analyses in 68 epileptic Beagle dogs in an epilepsy-prone colony, the most common areas of neuronal damage were the hippocampus, amygdala, piriform cortex, cerebral cortex, basal nuclei, claustrum, septal nuclei, and dorsal thalamic nuclei (152).…”

“…In addition to Beagles, PME has been described in several other breeds including the Basset hound, Chihuahua, French Bulldog, Pointer, Miniature Poodle, Miniature Dachshund, and Welsh Corgi ( 49 , 265 ). More recently, PME in Beagle dogs has been characterized in more detail ( 266 ).…”