Charles Bonnet syndrome and vitamin B12 deficiency: a case report.

The Charles Bonnet syndrome (CBS) is a condition associated with complex visual hallucinations occurring in the elderly in patients with visual impairment and normal mental health. Here, we report the case of a 78-year-old woman who has a limited visual acuity with a CBS that we postulated to be in relationship to a vitamin B12 deficiency. This case is the first report of vitamin B12 deficiency-associated CBS.

The role of coagulation marker fibrin D-dimer in early diagnosis of catatonia.

Catatonia is a common but under-diagnosed neuropsychiatric syndrome characterized by the occurrence in a single patient of concomitant affective, motor and behavioral symptoms with a hazardous outcome (called lethal catatonia: LC). Deaths by thromboembolic disease have been previously reported in LC. A 2-year prospective study was carried out to examine D-dimer levels, an early and sensitive coagulation marker, in patients with catatonic disorders. Twenty-five acute catatonic patients and 50 psychiatric control patients - matched on age, gender, psychiatric diagnosis, general psychopathology and neuroleptic medication matched - were investigated and considered in relation to D-dimer blood levels and other biological variables (serum iron, creatine phosphokinase, leukocytosis). All catatonic patients had high D-dimer levels and mean levels were significantly higher in catatonics than in non-catatonic patients, independently of age, gender, immobility, comorbid diagnosis, general psychopathology and neuroleptic medication. No significant association was observed with other biological parameters investigated. These preliminary and exploratory results suggest that catatonia is associated with early coagulation activation.

No pathogenic rearrangement within the DISC 1 gene in psychosis.

A translocation disrupting the DISC 1 gene segregates with schizophrenia and related psychiatric disorders in a large Scottish family. Mutation screening of this gene by routine PCR-based methods has remained largely negative. We sought to detect rearrangements affecting DISC 1 in 347 individuals meeting the DSM3R criteria for schizophrenia or schizoaffective disorder, 70 subjects with bipolar disorder and 377 psychiatrically healthy controls, but failed to detect any pathological rearrangement.

P50 inhibitory gating deficit is correlated with the negative symptomatology of schizophrenia.

Abnormal sensory gating in schizophrenia has frequently been reported. The strength of central inhibitory pathways was measured using the P50 component of the auditory evoked potential in a conditioning-testing paradigm. The relationships between a relative decrease in P50 amplitude to repeated auditory stimuli and clinical symptoms remain controversial. Using the Positive and Negative Syndrome Scale, we studied the P50 auditory conditioning-testing paradigm in 81 schizophrenic subjects, categorized into subgroups with and without prominent negative symptoms, in comparison with 88 control subjects. We found increased ratios of testing stimuli to conditioning stimuli in both schizophrenic subgroups relative to findings in the control group. In addition, we found significantly increased mean latencies of the P50 responses to conditioning (C) and testing (T) stimuli and significantly increased T/C ratios in the subgroup with negative symptoms compared with the subgroup with non-negative symptoms.

PRODH mutations and hyperprolinemia in a subset of schizophrenic patients.

The increased prevalence of schizophrenia among patients with the 22q11 interstitial deletion associated with DiGeorge syndrome has suggested the existence of a susceptibility gene for schizophrenia within the DiGeorge syndrome chromosomal region (DGCR) on 22q11. Screening for genomic rearrangements of 23 genes within or at the boundaries of the DGCR in 63 unrelated schizophrenic patients and 68 unaffected controls, using quantitative multiplex PCR of short fluorescent fragments (QMPSF), led us to identify, in a family including two schizophrenic subjects, a heterozygous deletion of the entire PRODH gene encoding proline dehydrogenase. This deletion was associated with hyperprolinemia in the schizophrenic patients. In addition, two heterozygous PRODH missense mutations (L441P and L289M), detected in 3 of 63 schizophrenic patients but in none among 68 controls, were also associated with increased plasma proline levels. Segregation analysis within the two families harboring respectively the PRODH deletion and the L441P mutation showed that the presence of a second PRODH nucleotide variation resulted in higher levels of prolinemia. In two unrelated patients suffering from severe type I hyperprolinemia with neurological manifestations, we identified a homozygous L441P PRODH mutation, associated with a heterozygous R453C substitution in one patient. These observations demonstrate that type I hyperprolinemia is present in a subset of schizophrenic patients, and suggest that the genetic determinism of type I hyperprolinemia is complex, the severity of hyperprolinemia depending on the nature and number of hits affecting the PRODH locus.