Progressive myoclonus and epilepsy with dentatorubral degeneration: a clinicopathological study of the Ramsay Hunt syndrome.

Abstract

SUMMARY Ramsay Hunt's progressive myoclonus and epilepsy associated with dentatorubral degeneration is a rare disorder. We report a 19 year old woman with this clinical syndrome wlho also has a more mildly affected brother. Neuropathological examination of the young woman showed spinocerebellar and cerebral cortical degeneration in addition to dentatorubral involvement. The evidence suggests that this is a distinctive hereditary disorder producing neuronal degeneration at several levels in the central nervous system.Progressive myoclonic cerebellar dyssynergia with epilepsy is an uncommon clinical syndrome with multiple causes. Harriman and Millar (1955) divide progressive familial myoclonic epilepsy into three categories. The first is a relatively uniform group associated with intracellular inclusions (Lafora bodies), and the second is associated with various cerebral lipidoses. The third category is a heterogeneous group of nonspecific degenerative diseases which include dyssynergia cerebellaris myoclonica of Ramsay Hunt. This syndrome has also been called dentatorubral degeneration based on the postmortem findings of the case reported by Hunt (1921). Subsequent reports of Ramsay Hunt's dentatorubral degeneration with pathological confirmation are scarce. We have evaluated a patient who seems to belong to this variety of progressive myoclonic epilepsy. The rarity and unusual nature of the syndrome justify documentation of the clinical and pathological details of this patient. In addition, other members of her family have possibly associated neurological findings which will also be described. Clinical summaryThe patient had a normal birth and development, and was an average student. At age 15 years she developed an awkward gait, clumsy hand coordination, and deteriorating school work. She soon developed nocturnal seizure activity, and an EEG revealed irregular runs of 4-5 Hz moderate voltage activity over the occipital areas, with bilateral spike discharges in these same regions. She was placed on anticonvulsant drugs and six months later began to complain of dull frontal headache.Neurological examination at this time showed marked horizontal nystagmus on lateral gaze to either side, dysarthria, slight dysmetria on fingerto-nose and heel-to-shin testing, poor rapid alternating movements with the left hand, ataxic gait, and a fine tremor of the head and hands. Deep tendon reflexes were normal and plantar responses were downgoing. Unusually high arched feet were noted.Cerebrospinal fluid contained 11.2 g/l protein, 3.3 mmol/l (60 mg/dl) sugar, one mononuclear cell per mm3, and negative VDRL. Skull radiographs, pneumoencephalogram, and brain scan were normal. She was treated with a combination of mephobarbitone, diphenylhydantoin, and ethosuximide.Three months later deep tendon reflexes were 140

3p14 deletion is a rare contiguous gene syndrome: Report of 2 new patients and an overview of 14 patients

“…The phenotype was variable depending on the deletion size and its extent either in telomeric or centromeric direction, thus suggesting a contiguous gene etiology. A few genes within the 3p14p12 deletion seem to be dosage sensitive and merit attention as plausible candidates implicated in the cranio‐facial features, hearing impairment, eye abnormalities, and global developmental delay in affected individuals [Bird and Show, ; Sundaresan et al, ; Hannula‐Jouppi et al, ; Andrews et al, ; Lu et al, ; Schwarzbraun et al, ; Young et al, ; Bertoli‐Avella et al, ; Garden and La Spada, ; Carr et al, ; Hamdan et al, ; Horn et al, ; Tao et al, ].…”

Maternally inherited mitochondrial myopathy and myoclonic epilepsy

“…Gliosis, neuronal loss, spongiform encephalopathy, leukoencephalopathy, and vascular proliferation have been noted by previous authors IS, 14, 281. There are no published reports of the electrophysiological characteristics of myoclonic epilepsy associated with mitochondrial myopathy in such a wide clinical spectrum of disease. In other reports of inherited myoclonic epilepsies, EEGs typically showed generalized spike-and-wave, polyspike activity, distinct photic sensitivity, and slow background activity [3,27). EEGs over many years are said to show increasing amounts of abnormal spike activity {27}.…”

Ramsay hunt syndrome and coeliac disease: A new association?

“…One of the known causes of the Ramsay Hunt syndrome is an underlying spinocerebellar degeneration, as described in the original report (1) and in some other patients (2)(3)(6)(7)(8)(9)(10)(11)(12). It is possible that the present two patients have a cerebellar degeneration (of unknown cause), similar to that previously described in association with coeliac disease.…”

“…In the right-hand panel, the back average (n = 44) of EEG activity preceding spontaneous jerks in the left tibialis anterior (TA) is shown. A positive wave was recorded some 40 ms before the onset of the muscle jerks (normal latency 2 1 SD on electrical stimulation of the motor cortex to TA is 29.2 2 1.2 ms) (vertical broken lines). This waveform was maximal over the vertex and its topography corresponds to the leg area of the somatosensory cortex, in contrast to that of the potential preceding the jerks in APB (see above A), which were largest laterally over the hand area of the sensorimotor cortex.…”