Oddball neurologic disorders: dogs (Proceedings)


Oddball neurologic disorders: dogs (Proceedings)

Oct 01, 2008

Canine Epileptoid Cramping Syndrome (Spike's disease)

This is a poorly characterized problem in Border Terriers that may be a metabolic, neurological or muscle disorder! It may previously have been confused with canine epilepsy. Owners or breeders of the affected dogs have indicated that many affected dogs become asymptomatic through dietary changes. One factor that has contributed to the obscurity of this problem is that some of the cases involved only one or a few episodes.

Signs have varied: staggering, dizziness, exaggerated stretching, unusually slow and/or methodical posturing or walking, trembling, abdominal and lumbar muscle contractions, borborygmus and apparent intestinal pain, falling over, struggling to rise but unable to do so. Dogs are cognizant, responsive to stimuli.

Age of onset: Apparently any. But 2-6 years seems to be the average.

Frequency of episodes: varies from 1-2 x during the animal's lifetime to several times per week. In some dogs, signs are progressive in frequency and duration.

Dancing Doberman Disease

Dancing Doberman syndrome is poorly understood, but it is probably a peripheral neuropathy. The etiology is unknown. Thus far, it has only been described in Doberman pinschers with an age range of 6 months to 7 years. Signs are first observed in one hind limb and consist of flexion of the limb while standing. Similar signs then usually develop in the other hind limb, resulting in "bicycle" type motions when dog is standing: one hind leg flexes, is put down, and the other one flexes. Pain is not present. Oddly enough, pelvic limb spinal reflexes are often increased, rather than decreased, as one would expect for a peripheral neuropathy. Over months to years, clinical signs usually continue to progress to encompass proprioceptive deficits and paraparesis. In one case that was followed for 5 years, quadriparesis developed suggesting that the disease may progress to the thoracic limbs as well.

Needle electromyography is abnormal with positive waves, fibrillation potentials, and complex repetitive discharges (bizarre high frequency discharges) in the gastrocnemius muscle. Electromyographic changes also develop in front limb muscles. Muscle biopsy results have shown mild myofiber atrophy.

There is no treatment and signs do not resolve.

Sleep-associated Movements

Alternating phases of brain activity occur during sleep. The first stage of sleep is characterized by low frequency electrical activity, i.e. slow wave sleep. This is followed by rapid eye movement (REM) sleep. In people, REM sleep is characterized by rapid eye movements, irregular breathing, increased blood pressure, and loss of muscle tone. However, the brain is highly active, and the electrical activity recorded in the brain by EEG during REM sleep is similar to that recorded during wakefulness. REM sleep is usually associated with dreaming in people. Slow wave sleep alternates with REM sleep in cycles lasting about 20 minutes.

During REM sleep, animals will often groan or whimper slightly and move or twitch their limbs or face. This may occasionally be confused with a seizure or other abnormality. If the movements are sleep related the dog will wake up normally when it is awakened.

In some animals, the movements during sleep are abnormally excessive, even violent. Some dogs or cats may lift their head and propel themselves across the floor. Some have excessive running movements of the limbs. Some may attack inanimate objects or whatever is in their path if they are moving forward. In contrast to a seizure, dogs can be aroused during these episodes and awake with no confusion or incoordination. We think that these signs are similar to a sleep disorder in people called REM behavior disorder. Clonazepam is often successful at reducing the problem in affected dogs and people.