A case of Kleine-Levin syndrome examined with SPECT and neuropsychological testing

Abstract

A case of Kleine-Levin syndrome with typical periodic hypersomnia and bulimia was diagnosed. On examination with single photo emission tomography (SPECT) (CERETEC) during a relapse period and 2 weeks later there was marked cortical hypoperfusion of the frontal and temporal lobes, especially on the left side as well as in the right parietal lobe. Neuropsychological testing performed 1 week after a relapse showed a reduction in encoding to memory function of verbal learning indicating neocortical damage of the left fronto-temporal region. A follow-up 2 months later after the patient had spontaneously recovered showed only a slight left fronto-temporal disturbance. CT and MRI of the brain were normal although the MRI showed a large and asymmetric mamillary body. Neuropsychological testing 6 years after recovery showed pronounced reduction in short-time verbal and visual memory. Seven years after recovery SPECT demonstrated a normalized frontal perfusion but still a slight hypoperfusion in the left temporal lobe. Our results correlate to autopsy findings in two cases described previously.

Persistent deficits of visual recall in Kleine–Levin syndrome

“…[8][9][10] Recently, deficits of visual and verbal short-term memory during remission were reported in four patients with KLS. 6,7 One patient re-tested 6 years after spontaneous recovery showed pronounced reduction in short-term memory capacity along with persisting hypoperfusion of left temporal regions. 6 Persisting hypoperfusion in fronto-temporal regions even during asymptomatic intervals could be replicated by another group 4 leading to the hypothesis that patients with KLS may exhibit subtle or even progressive cognitive disturbances resulting from neocortical damage of fronto-temporal regions increasing proportionally with the number of episodes.…”

Kleine-Levin Syndrome Treated With Clarithromycin

“…Excitatory monoamines are either increased 4 or within normal limits in the CSF of KLS patients, 5 explaining the limited effectiveness of stimulants, which increase CSF monoamines, in treating this syndrome. This lack of monoaminergic involvement suggests a pathogenesis rooted in naturally occurring excess GABAergic signaling.…”

Kleine–Levin Syndrome

“…Neuropathological examinations have been carried out in three cases of typical KLS [26][27][28] and in one case of KLS, secondary to a presumptive brain tumor [29]: There were intense signs of inflammatory responses within the hypothalamus in two patients [26,28], mild inflammation in one patient [29], and none in the last patient [27]. More recently, single-photon emission computed tomography (SPECT) studies performed during symptomatic periods and asymptomatic intervals have shown decreased tracer perfusion in several regions, such as basal ganglia, thalamus, hypothalamus, and frontal, parietal, temporal, or occipital lobes [30][31][32][33][34][35]. A decrease of cerebrospinal fluid (CSF) hypocretin-1 from a normal level during an asymptomatic interval to a low normal level during a symptomatic period has been demonstrated in one case [36].…”