Unsuccessful treatment with levodopa of a parkinsonian patient with calcification of the basal ganglia

Fahr's syndrome due to hypoparathyroidism revisited: A case of parkinsonism and a review of all published cases

INTRODUCTION

Fahr's syndrome due to hypoparathyroidism refers to bilateral basal ganglia (BG) calcifications and manifests with movement disorders, seizures, cognitive and behavioral symptoms.

CASE PRESENTATION

We report a case of a 74-year-old woman, who presented with parkinsonism due to post-surgical hypoparathyroidism and normal DaT scan, despite extensive calcifications of the BG, periventricular white matter, and cerebellum.

METHODS

A comprehensive literature review of all reported cases of Fahr's syndrome due to hypoparathyroidism was conducted in the electronic databases PubMed and Web of science. Moreover, demographic and clinical characteristics of the patients overall were calculated and associated with radiological findings.

RESULTS

We reviewed a total of 223 cases with Fahr's syndrome due to hypoparathyroidism (124 female, 99 male). Mean age on presentation was 44.6 ± 17.7 years. Thirty nine percent of patients had idiopathic hypoparathyroidism, 35.4 % acquired and 25.6 % pseudohypoparathyroidism. Almost half of the patients had tetany, seizures or a movement disorder and approximately 40 % neuropsychiatric symptoms. The patients with a movement disorder had a 2.23 likelihood of having neuropsychiatric symptoms as well (OR 2.23, 95 % CI 1.29-3.87). Moreover, there was a statistically significant association between the phenotype severity (i.e. the presence of more than one symptom) and the extent of brain calcifications (χ² = 32.383, p = 0.009).

CONCLUSION

Fahr's syndrome is a rare disorder, which nonetheless manifests with several neurological symptoms. A head CT should be considered for patients with hypoparathyroidism and neurological symptoms. More studies using DaT scan are needed to elucidate the effects of calcifications on the dopaminergic function of the BG.

Bilateral strio-pallido-dentate calcinosis (Fahr's disease): report of seven cases and revision of literature

BACKGROUND

Fahr's disease is rare a neurodegenerative idiopathic condition characterized by symmetric and bilateral calcifications of basal ganglia, usually associated with progressive neuropsychiatric dysfunctions and movement disorders. The term "Fahr's syndrome" is used in presence of calcifications secondary to a specific cause, but the variability of etiology, pathogenesis, and clinical picture underlying this condition have raised the question of the real existence of a syndrome. Several classifications based on the etiology, the location of brain calcifications and the clinical presentation have been proposed. Here we describe seven clinical cases of basal ganglia calcifications, in order to search for pathognomonic features and correlations between clinical picture and imaging findings.

CASES PRESENTATION

The patients came to our attention for different reasons (most of them for memory/behavior disturbances); all underwent neuro-psychologic evaluation and neuro-imaging. All patients showed variable degrees of deterioration in cognitive function; anxiety and depression were frequent too, and resistant to treatment in all cases. Less frequent, but severe if present, were psychotic symptoms, with different grade of structure and emotional involvement, and always resistant to treatment. We observed only few cases of extrapyramidal disorders related to the disease itself; anyway, mild extrapyramidal syndrome occurred quite frequently after treatment with antipsychotics.

CONCLUSION

Based on these findings we discourage the use of the term "Fahr's syndrome", and suggest to refer to Idiopathic or Secondary basal ganglia calcification. Unlike early onset forms (idiopathic or inherited), the clinical presentation of late onset form and Secondary basal ganglia calcification seems to be really heterogeneous. Case-control studies are necessary to determine the actual significance of basal ganglia calcification in the adult population and in the elderly, in cognitive, physical and emotional terms.

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.

Mineralization of the basal ganglia: implications for neuropsychiatry, pathology and neuroimaging

This article examines the evidence for and against the existence of basal ganglia mineralization as a defined clinico-pathological entity. In reviewing the literature on basal ganglia mineralization, this article emphasizes evidence derived from different neuroimaging modalities, genetics, metabolic studies, postmortem series and their possible neuropsychiatric correlates. Relevant articles were collected through Medline and Index Medicus searches. Researchers have encountered multiple difficulties in accepting basal ganglia mineralization as a distinct entity. This syndrome lacks set clinical criteria or a unique etiology; not surprisingly, numerous articles have applied varied definitions. Because many of the reported cases have not been examined postmortem, both the extent and nature of their mineralization remains uncertain. Furthermore, researchers have considered small foci of basal ganglia mineralization a normal phenomenon of aging. However, when brain deposits are extensive, they are associated with a set of age-dependent, progressive clinical symptoms. They include cognitive impairment, extrapyramidal symptoms and psychosis. Most cases are related to abnormalities of calcium metabolism, but rare familial cases of idiopathic origin have been reported. Overabundant mineralization of the brain is judged pathological based on its amount, distribution and accompanying clinical symptoms. Although its relation with calcium dysregulation is well known, modern studies have emphasized abnormalities of iron and dopamine metabolism. The authors suggest that these metabolic abnormalities may link basal ganglia mineralization to psychotic symptomatology.

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.

Bilateral striopallidodentate calcinosis: cerebrospinal fluid, imaging, and electrophysiological studies

We report the genetic, clinical, electrophysiological, and imaging studies in a family with bilateral striopallidodentate calcinosis (Fahr's disease). The intracerebral calcium deposits occurred before onset of the symptoms in the third decade of life. Progressive neurological deterioration occurred in the fifth decade of life in the proband. Cerebrospinal fluid homocarnosine, a central nervous system-specific peptide, was increased twofold in patients with autosomal dominant bilateral stripallidodentate calcinosis; in sporadic cases, there was no detectable homocarnosine and a decreased level of histidine. With advancing age, the amount of calcification increases, but it has not been determined if a critical amount must be reached before symptoms occur. Computerized tomography is superior to magnetic resonance imaging for radiological diagnosis. Despite diffuse striatal calcification, striatal 6-[18F]fluoro-L-dopa uptake did not reveal any difference between patients and control subjects, from which we infer persisting integrity of the nigrostriatal dopaminergic pathway.

Basal ganglia calcifications in postoperative hypoparathyroidism: a case with unusual characteristics

A patient is described with post-thyroidectomy hypoparathyroidism and basal ganglia calcifications. The patient presented with a tonic-clonic seizure. The calcifications shown on CT scan were extensive in the basal ganglia, the bifrontal periventricular white matter and even in the brainstem. The white matter with calcifications displayed a high signal intensity on MRI, probably due to a different stage of the calcifying process in the white matter than in the basal ganglia. A severe dystonic reaction was observed after phenothiazine therapy and is discussed.

Contribution of CT scan to the diagnosis of Fahr's syndrome

Of 7040 patients who were examined with CT scan for various reasons, 72 (1.02%) showed symmetrical intracranial calcifications. On the basis of the extent of the calcifications, the patients were divided into 3 groups of which the first (10 cases), with extensive calcifications, showed clear findings of hypoparathyroidism; the second (4 cases), with less extensive calcifications, showed borderline laboratory findings and the third (58 cases), with calcifications only in the internal part of the globus pallidus, had no relation to any disturbance of the parathyroid function. The limited percentage (4.2%) of calcifications detected by ordinary cranial X-rays was discussed as compared to those diagnosed by CT scan; this is due to the weakening of the relationship which existed in the past between hypoparathyroidism and calcifications. Patients with extensive calcifications do not seem to have a significantly higher proportion of neurological impairment (35.8%) than patients who showed limited calcifications (34.5%). On the other hand, patients with extensive calcifications showed more frequent mental disorders (50%) compared to those who showed limited calcifications (34.5%). The proportion of mental disorders is still higher in patients with dilatation of the subarachnoid spaces (56.7%) compared to those who do not show dilatation (23.8%). Finally, of the 72 patients with calcifications, 15 (20.8%) showed extrapyramidal syndrome, possibly due to calcium salt deposits in the metasynaptic dopamine receptors while 13 (18%) were taking anticonvulsant drugs which, apart from influencing the metabolism of calcium, also influence the activity of alkaline phosphatase and are involved in the creation of calcifications.

Intracranial bilateral symmetrical calcification on CT-scanning. A case report and a review of the literature

The case of a 57-year-old woman with idiopathic hypoparathyroidism is presented. A CT-scan showed extensive bilateral symmetrical calcification in the region of the basal ganglia, nuclei of the cerebellum and the cerebral and cerebellar white matter. A review of the literature showed that bilateral symmetrical calcification detected by CT is usually small in extent and is most often confined to the globus pallidus. It is most commonly found in patients older than 50 years, who only rarely have symptoms associated with it. The finding is, though, non-specific and may occur in a variety of pathological conditions both with and without an aetiological relationship. Further study of the cerebral parathormone responsive adenylate cyclase enzyme proves hopeful to elucidate the aetiology of idiopathic bilateral symmetrical calcification.

Calcification of the basal ganglia following carbon monoxide poisoning

Minor calcification of the basal ganglia was demonstrated by computed tomography in a woman, aged 66, who had survived carbon monoxide poisoning 48 years earlier. Extensive neuropathological investigations have demonstrated calcified lesions of the basal ganglia in a number of conditions, but their frequency and topographic distribution in vivo remain to be elucidated, by means of CT.