Familial idiopathic strio-pallido-dentate calcifications with late onset extrapyramidal syndrome

Primary familial brain calcification: Genetic analysis and clinical spectrum

BACKGROUND

Primary familial brain calcification (PFBC) is a rare autosomal dominant disorder with bilateral calcification of basal ganglia and other cerebral regions, movement disorders, and neuropsychiatric disturbances. So far, three causative genes have been discovered: SLC20A2, PDGFRB and PDGFB, accounting for approximately 50% of cases.

METHODS

Seven unrelated families with primary brain calcification were recruited to undergo clinical and genetic analysis, including Sanger sequencing of SLC20A2, PDGFRB, and PDGFB, and copy number analysis of SLC20A2.

RESULTS

Mutations in SLC20A2 have been detected in three families: p.Glu368Glyfs*46, p.Ser434Trp, and p.Thr595Met. Intrafamilial phenotype variability has been observed. In spite of this, we found similar neuroimaging pattern among members of the same family.

CONCLUSIONS

This molecular analysis expands the mutational spectrum of SLC20A2, which remains the major causative gene of primary familial brain calcification, and suggests the existence of disease-causing mutations in at least another, still unknown gene.

Identification of neural targets for the treatment of psychiatric disorders: the role of functional neuroimaging

Neurosurgical treatment of psychiatric disorders has been influenced by evolving neurobiological models of symptom generation. The advent of functional neuroimaging and advances in the neurosciences have revolutionized understanding of the functional neuroanatomy of psychiatric disorders. This article reviews neuroimaging studies of depression from the last 3 decades and describes an emerging neurocircuitry model of mood disorders, focusing on critical circuits of cognition and emotion, particularly those networks involved in the regulation of evaluative, expressive and experiential aspects of emotion. The relevance of this model for neurotherapeutics is discussed, as well as the role of functional neuroimaging of psychiatric disorders.

Strio-pallido-dentate calcinosis: a diagnostic approach in adult patients

Familial idiopathic bilateral strio-pallido-dentate calcinosis is a rare autosomal dominant disorder characterized by massive symmetric calcification, detectable by CT, into the globus pallidus and striatum, with or without the involvement of the dentate nucleus, thalamus and white matter in the absence of alterations of calcium metabolism. Clinically, it has been associated with movement and/or neuropsychiatric disorders with age at onset typically in the fourth or fifth decade. Other sporadic or familial diseases can be responsible for brain calcifications with a similar anatomic strio-pallidal or strio-pallido-dentate pattern and, a restricted number of them, for neurological symptoms with onset in adulthood. Moreover, physiological age-related basal ganglia calcifications are often incidentally found, although with a far different CT aspect, in elderly patients with movement disorders. Indentifying familial and idiopathic cases may offer the opportunity to study the molecular mechanisms underlying this minerals deposition.

Cortico-basal ganglia circuitry: a review of key research and implications for functional connectivity studies of mood and anxiety disorders

There is considerable evidence that dysfunction of the cortico-basal ganglia circuits may be associated with several mood and anxiety disorders. However, it is unclear whether circuit abnormalities contribute directly either to the neurobiology of these conditions or to the manifestation of symptoms. Understanding the role of these pathways in psychiatric illness has been limited by an incomplete characterization of normal function. In recent years, studies using animal models and human functional imaging have greatly expanded the literature describing normal cortico-basal ganglia circuit function. In this paper, recent key studies of circuit function using human and animal models are reviewed and integrated with findings from other studies conducted over the previous decades. The literature suggests several hypotheses of cortico-basal ganglia circuitry function in mood and anxiety disorders that warrant further exploration. Hypotheses are proposed herein based upon the cortico-basal ganglia mechanisms of: (1) feedforward and feedback control, (2) circuit integration and (3) emotional control. These are presented as models of circuit function, which may be particularly relevant to future investigations using neuroimaging and functional connectivity analyses.

Neurosteroid hormone vitamin D and its utility in clinical nutrition

PURPOSE OF REVIEW

Vitamin D is a seco-steroid hormone with multiple functions in the nervous system. We discuss clinical and experimental evidence of the role of vitamin D in normal and pathological brain functions, and analyze the relative importance of vitamin D-modulated brain mechanisms at different stages of life. We also outline perspectives for the use of vitamin D in clinical nutrition to prevent or treat various brain disorders.

RECENT FINDINGS

Numerous brain dysfunctions are linked to vitamin D deficits and/or dysfunctions of its receptors. In both animals and humans, vitamin D serves as an important endogenous and/or exogenous regulator of neuroprotection, antiepileptic and anticalcification effects, neuro-immunomodulation, interplay with neurotransmitters and hormones, modulation of behaviors, brain ageing, and some other, less-explored, brain processes.

SUMMARY

Vitamin D emerges as an important neurosteroid hormone in the brain, with a strong potential for age-specific applications in clinical nutrition.

Thalamic calcification in vitamin D receptor knockout mice

Vitamin D is a steroid hormone with many important functions in the brain, mediated through the nuclear vitamin D receptor. Here, we report that aging nuclear vitamin D receptor knockout mice demonstrate a symmetric thalamic calcification with numerous Ca/P-containing laminated bodies. These results are consistent with clinical findings showing brain calcification in patients with vitamin D deficiency. Our results suggest that nuclear vitamin D receptor deficiency leads to brain mineralization in vitamin D receptor knockout mice, which may represent an experimental model of intracranial calcification.

Basal ganglia volumetric studies in affective disorder: what did we learn in the last 15 years?

Until today, morphometric neuroimaging studies on affective disorders concentrate on the limbic system, especially the hippocampus, amygdala, and anterior cingulate. In most of the studies and reviews available today, the basal ganglia are of secondary interest. It seems that the basal ganglia are interest of neurologist, whereas the limbic system is reserved for psychiatric neuroimaging studies. We follow a different approach in this review, studying all available papers on MRI research of the basal ganglia in unipolar depression and bipolar disorder. We found a possibly larger neostriatum in bipolar and possibly smaller one in unipolar patients. None of the unipolar studies found any larger basal ganglion, and only one out of 12 bipolar studies found smaller basal ganglia. Both findings seemed to depend on age (tendency toward smaller volumes in unipolar and bipolar with older age), sex (men tending to pathology in both disorders) and bipolar patients show a possible influence of medication, which is not assessed so far in unipolar depression. We conclude that several methodological shortcomings in volumetric MRI research on the basal ganglia in affective disorders make it necessary to imply more research in this area. We suggest (a) better MRI methods (we do not have a single volumetric 3 Tesla study in this patient group); (b) studies of medication-naïve patients (thus ruling out the medication effect); (c) Studies that directly compare unipolar depressed and bipolar patients are needed to determine whether these apparent differences in morphometric abnormalities, as observed through the mediating comparison with healthy subjects, are real.

What is and what is not 'Fahr's disease'

Bilateral almost symmetric calcification involving striatum, pallidum with or without deposits in dentate nucleus, thalamus and white matter is reported from asymptomatic individuals to a variety of neurological conditions including autosomal dominant inheritance to pseudo-pseudohypoparathyroidism. While bilateral striopallidodentate calcinosis is commonly referred to as 'Fahr's disease' (a misnomer), there are 35 additional names used in the literature for the same condition. Secondary bilateral calcification is also reported in a variety of genetic, developmental, metabolic, infectious and other conditions. In autosomal dominant or sporadic bilateral striopallidodentate calcinosis no known calcium metabolism abnormalities are known to date. Clinically, parkinsonism or other movement disorders appear to be the most common presentation, followed by cognitive impairment and ataxia. When presence of movement disorder, cognitive impairment and ataxia are present, a computed tomography scan of the head should be considered to rule-in or rule-out calcium deposits. Calcium and other mineral deposits cannot be linked to a single chromosomal locus. Further genetic studies to identify the chromosomal locus for the disease are in progress.

Genetics of parkinsonism

Parkinson's disease (PD) was noted to have a familial component as early as 1880 (Leroux, 1880). More recently, the discovery of several genetic factors influencing parkinsonism has emphasized the importance of heredity in PD. The clinical spectrum of familial parkinsonism is wide; it includes not only PD, but also dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP), essential tremor, and other disorders. In the general population, it is likely that PD results from combined genetic and environmental factors, most of which are not yet known. The discovery of causal mutations in the gene for alpha-synuclein, parkin, and of genetic linkages to chromosomes 2p4, 4p5, and three loci on 1q6-8 have revolutionized PD research. This review focuses on recent progress in the Mendelian genetics of PD and those diseases in which parkinsonism is a prominent feature, and considers how these discoveries modify our beliefs regarding the etiology and pathogenesis of these disorders.

Parkinsonism associated with autosomal dominant bilateral striopallidodentate calcinosis

Bilateral striopallidodentate calcinosis (BSPDC, also known as Fahr's disease, a misnomer), is a rare disorder where bilateral, almost symmetric, calcium and other mineral deposits occur in subcortical nuclei and white matter. Neurological manifestations vary but movement disorders are the most common. Of the movement disorders, parkinsonism predominates. We describe 6 patients with BSPDC associated with parkinsonism. Of the 6 patients, one patient from an autosomal dominantly inherited family who responded to levodopa, showed Lewy bodies in substantia nigra neurons and changes consistent with BSPDC. Another patient, from the same family with clinical evidence of parkinsonism and radiological and neuropathological evidence of BSPDC, did not show Lewy bodies. Ten patients with BSPDC and parkinsonism (without evidence of parathyroid dysfunction) were found in the literature. When parkinsonism is associated with dementia and cerebellar signs, obtaining a CT scan may be helpful as BSPDC often presents with the above three conditions.

Anatomical MRI study of basal ganglia in bipolar disorder patients

This study examined possible anatomical abnormalities in basal ganglia structures in bipolar disorder patients. Caudate and putamen gray matter volumes, and globus pallidus total volume were measured with magnetic resonance imaging (MRI) in 22 DSM-IV bipolar patients (age+/-S.D.=36+/-10 years; eight drug-free and 14 lithium monotherapy patients) and 22 matched healthy control subjects (age+/-S.D.=38+/-10 years). No significant differences were found between bipolar patients and healthy control subjects for any of the basal ganglia measures (t-tests, P>0.05). Age was inversely correlated with left putamen volumes in patients (R=-0.44, P=0.04), but not in healthy control subjects (R=-0.33, P=0.14). Older patients (>36 years old) had a significantly larger left globus pallidus than younger ones (< or =36 years old) (ANOVA, P=0.01). In a multiple regression analysis, after entering age as independent variable, the length of illness predicted smaller left putamen volumes, explaining 10.4% of the variance (F=4.07, d.f.=2, P=0.03). No significant effects of episode type, number of prior episodes, or gender were found in any basal ganglia measurements (ANOVA, P>0.05). In conclusion, our findings indicate that the basal ganglia may be anatomically preserved in bipolar patients. This is in contrast to available findings for unipolar disorder. However, our findings also suggest that age and length of illness may have significant effects on basal ganglia structures in bipolar patients, which may be more pronounced among bipolar I patients, and of relevance for the pathophysiology of the disorder.

Bilateral striopallidodentate calcinosis: clinical characteristics of patients seen in a registry

Clinical features in bilateral striopallidodentate calcinosis (BSPDC), popularly referred to as Fahr's disease (five autosomal dominant families and eight sporadic cases, n = 38), recruited through a registry, are reported. Applying uniform criteria, cases reported in the literature (n = 61) were combined for detailed analysis. The mean (+/- S.D.) age of Registry patients was 43 +/- 21 and that of literature was 38 +/- 17. In combined data set (n = 99), 67 were symptomatic and 32 were asymptomatic. Of the symptomatic, the incidence among men was higher compared with women (45:22). Movement disorders accounted for 55% of the total symptomatic patients. Of the movement disorders, parkinsonism accounted for 57%, chorea 19%, tremor 8%, dystonia 8%, athetosis 5%, and orofacial dyskinesia 3%. Overlap of signs referable to different areas of central nervous system (CNS) was common. Other neurologic manifestations included: cognitive impairment, cerebellar signs, speech disorder, pyramidal signs, psychiatric features, gait disorders, sensory changes, and pain. We measured the total volume of calcification using an Electronic Planimeter and Coordinate Digitizer. Results suggest a significantly greater amount of calcification in symptomatic patients compared to asymptomatic patients. This study suggests that movement disorders are the most common manifestations of BSPDC, and among movement disorders, parkinsonism outnumber others.