Anti-NMDA-receptor antibody detected in encephalitis, schizophrenia, and narcolepsy with psychotic features.

BACKGROUND: Causative role of encephalitis in major psychotic features, dyskinesias (particularly orofacial), seizures, and autonomic and respiratory changes has been recently emphasized. These symptoms often occur in young females with ovarian teratomas and are frequently associated with serum and CSF autoantibodies to the NMDA receptor (NMDAR). METHODS: The study included a total of 61 patients from age 15 to 61 and was carried out between January 1, 2005, and Dec 31, 2010. The patients were divided into the following three clinical groups for comparison. Group A; Patients with typical clinical characteristics of anti-NMDAR encephalitis. Group B; Patients with narcolepsy with severe psychosis. Group C; Patients with schizophrenia or schizo-affective disorders. RESULTS: Ten out of 61 cases were anti-NMDAR antibody positive in typical encephalitis cases (group A: 3 of 5 cases) and cases in a broader range of psychiatric disorders including narcolepsy (group B: 3 of 5 cases) and schizophrenia (group C: 4 of 51 cases). CONCLUSION: In addition to 3 typical cases, we found 7 cases with anti-NMDAR antibody associated with various psychotic and sleep symptoms, which lack any noticeable clinical signs of encephalitis (seizures and autonomic symptoms) throughout the course of the disease episodes; this result suggest that further discussion on the nosology and pathophysiology of autoimmune-mediated atypical psychosis and sleep disorders is required.

[Patient with limbic encephalitis associated with anti-voltage-gated potassium channel antibodies who presented with insomnia and hand tremor].

A 65-year-old man presented with bilateral postural hand tremor (3 Hz) followed by memory impairment, which improved spontaneously after admission to our hospital. Two weeks after admission, he had another bout of memory impairment and complained of insomnia. Brain magnetic resonance imaging (MRI) showed a signal intensity change in the medial part of the right temporal lobe, which suggested limbic encephalitis (LE). Serum hyponatremia and absence of cerebrospinal fluid pleocytosis suggested the possibility of anti-voltage-gated potassium channel (VGKC) antibody-associated LE. Serum hyponatremia and hand tremor showed immediate improvement after steroid pulse therapy, and memory impairment and insomnia showed gradual improvement. Brain MRI on day 110 of admission showed partial resolution of medial temporal signal abnormalities with mild bilateral hippocampal atrophy. Serological tests confirmed the clinical diagnosis of anti-VGKC antibody-associated LE. This report may expand the phenotypic profile of anti-VGKC antibody-associated LE, which is characterized by remission and relapse of disease course, insomnia, and hand tremor.

The circulating level of leptin and blood pressure in patients with multiple system atrophy.

Patients with multiple system atrophy (MSA) frequently exhibit orthostatic hypotension (OH). Leptin, an adipose-derived hormone, contributes to the sympathetic control of blood pressure (BP), and loss of leptin may cause OH. We aimed to clarify the relationship between leptin and OH in MSA. Serum leptin levels were measured in 36 patients with MSA, 25 patients with other atypical parkinsonian disorders (APDs), including progressive supranuclear palsy-Richardson syndrome and corticobasal syndrome, and 26 control subjects. Blood samples were obtained after fasting for 12h. In MSA patients, baseline BP was measured in the recumbent position after a 3-min rest, and orthostatic changes in BP were evaluated after 0-3 min of standing. Serum leptin levels did not differ significantly between MSA patients (5.9 ± 0.8 ng/ml), other APD patients (5.2 ± 0.8 ng/ml), and controls (6.1 ± 1.3 ng/ml; P=0.8). In MSA patients, serum leptin levels correlated significantly with body mass index (P=0.01), but not baseline BPs (systolic BP, P=0.20; diastolic BP, P=0.44) or orthostatic drop in BP (systolic BP, P=0.13; diastolic BP, P=0.58). Our observations indicated that the circulating level of leptin was preserved, and OH occurred independent of the leptin level in MSA patients.

Abnormal ghrelin secretion contributes to gastrointestinal symptoms in multiple system atrophy patients.

Patients with multiple system atrophy (MSA) often have evidence of compromised gastrointestinal motility. Ghrelin is a gut hormone that influences gastrointestinal motility in humans. The aim of this study was to determine whether ghrelin secretion is affected in MSA patients, and to investigate the relation between ghrelin secretion and gastrointestinal symptoms. Plasma levels of active ghrelin and unacylated ghrelin were measured in patients with MSA (n = 30), other atypical parkinsonian disorders including progressive supranuclear palsy-Richardson syndrome and corticobasal syndrome (n = 24), and control subjects (n = 24) using enzyme-linked immunosorbent assays. Gastrointestinal symptoms were quantified in all subjects using a self-report questionnaire. The ratio of active ghrelin to total ghrelin in the plasma (active ghrelin ratio) was lower in patients with MSA (mean: 8.0 %) than in patients with other atypical parkinsonian disorders (mean: 13.7 %, P = 0.001) and control subjects (mean: 13.9 %, P = 0.001). The active ghrelin ratio was correlated with the severity of gastrointestinal symptoms in MSA (r = -0.5, P = 0.004). Our observations indicate that ghrelin secretion is affected in patients with MSA. The low active ghrelin ratio may contribute to gastrointestinal symptoms in MSA.