Epilepsin, 33(6):1047-1050, 1992
Raven Press, Ltd., New York
0 International League Against Epilepsy

Adult Postanoxic “Erratic” Status Epilepticus
E. Bortone, G. Bettoni, C. Giorgi, A. Murgese, “M. Stocchetti, and D. Mancia
Neurological Institute und “Intensive Cure Unit, University of Parma, Parmu, Italy

Summary: A 66-year-old woman with posttraumatic anoxic coma after diffuse cerebral fat embolism had continuous alternating-side myoclonic jerks. Usually, this kind
of myoclonic status epilepticus (SE) occurs in newborn
infants. We postulate the unusual combination of diffuse

cerebral anoxia plus commissural fiber damage as a possible explanation. Key Words: Head injuries-Cerebral
anoxia-Cerebral hemorrhage-Status epilepticusMyoclonus-Fat embolism-Electroencephalography.

~

“Erratic” status epilepticus (SE), observed almost exclusively in newborn infants, is clinically
characterized by seizures involving localized segments on either side of the body anarchically. It is a
variant of unilateral alternating SE (Vigevano and
Gregory, 1987) caused by severe acute encephalopathy.
Consistent with the alternating appearance of
myoclonic jerks, the EEG epileptic discharges wander within and between the cerebral hemispheres.
CASE REPORT

A 66-year-old woman, without past o r family history of seizures, was admitted April 6 , 1990 to a
rural hospital after being involved in a car accident.
She had retrograde amnesia, a lacerated left frontoparietal skull wound, multiple leg bone fractures,
and hypovolemic shock. Brain computed tomography (CT) scan was normal. The following day, her
general condition worsened and she was transferred
to the Parma University Hospital intensive care
unit.
At that time, she was in a state of deep coma,
unresponsive to painful stimuli, with midriatic pupils unreactive to light. Brain CT scan showed a
small right parietal hemorrhagic lesion without
mass effect on the ventricular system. Operation
was performed.

Received April 1992; revision accepted June 1992.
Address correspondence and reprint requests t o Dr. E.
Bortone at Istituto di Neurologia Universiti di Parma, via del
Quartiere 4, 43100 Parma, Italy.

On April 10, clonic jerks were observed involving
the right hemiface o r right hand and, less frequently, left shoulder, forearm, or hemiface in a
completely independent and asynchronous fashion.
Mean duration of rnyoclonic jerks was -40 s, appearing at 5-min intervals. Treatment with intravenous (i.v.) phenytoin was started (initially 1 g followed by 500 mg daily), with progressive reduction
of seizure frequency and duration and complete
cessation on April 12. The patient’s general condition worsened progressively, however, and she died
on April 18 of pulmonary disease.
Four EEGs of a30 min were performed (Neurofax, Nihon-Kohden, Tokyo, Japan, 14 channels).
Needle electrodes were positioned according to the
International 10-20 system with bipolar montages;
simultaneous recording from the mylohyoideus
muscle was performed with a concentric needleelectrode.
Interictal EEG (Fig. 1A) showed suppression
burst activity completely asynchronous in either
hemisphere, whereas ictal EEG was characterized
by spikes and atypical spike wave or polyspike
wave complexes, with an alternating distribution on
either hemisphere. Electromyogram recording from
the mylohyoideus muscle showed short bursts of
interference pattern, corresponding to the myoclonic jerks (Fig. 1B and C).
Brain postmortem examination showed disseminated petechiae in the white and gray matter of the
cerebral and cerebellar hemispheres, brainstem,
and corpus callosum. In the right frontoparietal
white matter, was a confluent single area of hemorrhagic softening (2 X 1.5 cm). The anatomic diagnosis was disseminated hemorrhagic encephalopa1047

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Epilepsia, Vol. 33, N o . 6 , 1992

E. BORTONE ET AL.

“ERRATIC” SE

g

1049

C

‘

___---

-- -..

‘,”v”L1 Sec
FIG. 1. lnterictal EEG: Suppression burst activity asynchronous in either hemisphere (A). lctal EEG: Spikes and atypical
spike-wave or polyspike-wave complexes in right B and left hemisphere (C). Electromyogram recording from mylohyoideus (myl)
muscle.

thy (purpura cerebri) owing to multiple fat embolism (Fig. 2).
DISCUSSION
Cerebral anoxia is a most frequent cause of myoclonic SE (Lance and Adams, 1963). Celesia et al.
(1988) have hypothesized that myoclonic SE is a
“fragment” of tonic-clonic generalized seizures.
During anoxic encephalopathy , a peculiar combination of damage occurs, both in the cerebral structures responsible for propagation and generalization
of epileptic activity (cortex and thalamus) and in
those responsible for normal tonic inhibitory function (basal ganglia and cerebellum).
Although myoclonic seizures are frequently observed in the course of postanoxic coma, adult electroclinical “alternating” myoclonic seizures are
rather unusual. A similar type of alternating seizures, originating from either hemisphere and characterized by localized and asynchronous myoclonic
jerks in distinct muscular segments, is &served in
newborn infants (e.g., early myoclonic encephalop-

FIG. 2. Coronal section through the basal ganglia with disseminated petechiae, predominant in the white matter, basal
ganglia, and corpus callosum.
Epilepsia, Vol. 33, No. 6 , 1992

E. BORTONE ET AL.

1050

athy). In these cases, immaturity of cerebral structures could play a fundamental role in determining
the peculiar semiology of seizures.
Alternating seizures have also been described in
the course of malformation syndromes, such as the
“split-brain’’ of Aicardi’s syndrome (Aicardi et al.,
1969).That the spike discharges emanating from the
left and right hemispheres appear to be out of phase
would lend some support to the hypothesis that a
relation exists with the corpus callosum as occurs in
Aicardi’s syndrome.
In our case, the damage to the callosal fibers
could justify independent electrical activity of right
and left hemisphere. We postulate that the unusual
combination of diffuse cerebral anoxia plus commissural fiber damage is the necessary requisite to
produce this type of erratic SE in adults.
REFERENCES
Aicardi J, Chevrie JJ, Rousselie F . Le syndrome spasmes en
flexion, agCnCsie calleuse, lacunes choriorktiniennes. Arch Fr
Pediatr 1969;26:1103.
Celesia GG, Grigg MM, Ross E. Generalized status myoclonicus
in acute anoxic and toxic-metabolic encephalopathies. Arch
Neurol 1988;45:7814.

Epilepsia, Vol. 33, NO. 6, 1992

Lance JW, Adams RD. The syndrome of intention or action
myoclonus as a sequel to hypoxic encephalopathy. Brain
1963;86:1 1 1-36.
Vigevano F, Gregory S. Status epilepticus in the paediatric age.
J Pediatr Neurosci 1987;3:213-4.

RESUME
Les auteurs rapportent l’observation d’une femme Bgee de 66
ans, prtsentant un coma anoxique post-traumatique resultant
d’une embolie graisseuse cCrCbrale diffuse, avec des secousses
myocloniques continues alternant d’un cBtC a I’autre. Ce type
d’Ctat de ma1 myoclonique est habituellement constate chez les
nouveaux-nCs. Les auteurs emettent l’hypoth8se que ce tableau
clinique pourrait &re expliquk par la combinaison inhabituelle
d’une anoxie ctrebrale diffuse et d’une atteinte des fibres commissiirales.
(P. Genton, Marseille)

ZUSAMMENFASSUNC
Eine 66 Jahre alte Frau mti posttraumatischem anoxischem
Koma nach diffusen cerebralen Fettembolien bot kontinuierliche
seitenwechselnde myoklonische Zuckungen. In der Regel wird
diese Art von myoklonischem Status epilepticus nur beim Neugeborenen beobachtet. Als mogliche Erklarung nehmen wir ein
ungewohnliches Zusammentreffen von diffuser cerebraler Anoxie und Schadigung der Kommisurenfasern an.
(C. G. Lipinski, HeidelherglNeckurgemund)