Juvenile Gaucher's disease with horizontal gaze palsy in three siblings

Eye movement biomarkers allow for the definition of phenotypes in Gaucher Disease

BACKGROUND

Neurological forms of Gaucher disease, the inherited disorder of β-Glucosylceramidase caused by bi-allelic variants in GBA1, is a progressive disorder which lacks a disease-modifying therapy. Systemic manifestations of disease are effectively treated with enzyme replacement therapy, however, molecules which cross the blood-brain barrier are still under investigation. Clinical trials of such therapeutics require robust, reproducible clinical endpoints to demonstrate efficacy and clear phenotypic definitions to identify suitable patients for inclusion in trials. The single consistent clinical feature in all patients with neuronopathic disease is the presence of a supranuclear saccadic gaze palsy, in the presence of Gaucher disease this finding serves as diagnostic of 'type 3' Gaucher disease.

METHODS

We undertook a study to evaluate saccadic eye movements in Gaucher patients and to assess the role of the EyeSeeCam in measuring saccades. The EyeSeeCam is a video-oculography device which was used to run a protocol of saccade measures. We studied 39 patients with non-neurological Gaucher disease (type 1), 21 patients with type 3 (neurological) disease and a series of 35 healthy controls. Mean saccade parameters were compared across disease subgroups.

RESULTS

We confirmed the saccadic abnormality in patients with type 3 Gaucher disease and identified an unexpected subgroup of patients with type 1 Gaucher disease who demonstrated significant saccade parameter abnormalities. These patients also showed subtle neurological findings and shared a GBA1 variant.

CONCLUSIONS

This striking novel finding of a potentially attenuated type 3 Gaucher phenotype associated with a specific GBA1 variant and detectable saccadic abnormality prompts review of current disease classification. Further, this finding highlights the broad spectrum of neuronopathic Gaucher phenotypes relevant when designing inclusion criteria for clinical trials.

Ophthalmic manifestations of Gaucher disease: the most common lysosomal storage disorder

Gaucher disease (GD) results from a deficiency of glucocerebrosidase activity and the subsequent accumulation of the enzyme's metabolites, principally glucosylsphingosine and glucosylceramide. There are three principal forms: Type I, which is the most common, is usually considered non-neuronopathic. Type II, III and IIIc manifest earlier and have neurological sequelae due to markedly reduced enzyme activity. Gaucher's can be associated with ophthalmological sequelae but these have not been systematically reviewed. We therefore performed a comprehensive literature review of all such ophthalmic abnormalities associated with the different types of Gaucher disease. We systematically searched the literature (1950 - present) for functional and structural ocular abnormalities arising in patients with Gaucher disease and found that all subtypes can be associated with ophthalmic abnormalities; these range from recently described intraocular lesions to disease involving the adnexae, peripheral nerves and brain. In summary, Gaucher can affect most parts of the eye. Rarely is it sight-threatening; some but not all manifestations are amenable to treatment, including with enzyme replacement and substrate reduction therapy. Retinal involvement is rare but patients with ocular manifestations should be monitored and treated early to reduce the risk of progression and further complications. As Gaucher disease is also associated with Parkinsons disease and may also confer an increased risk of malignancy (particularly haematological forms and melanoma), any ocular abnormalities should be fully investigated to exclude these potential underlying conditions.

Eye movement impairment recovery in a Gaucher patient treated with miglustat

In Gaucher Disease (GD) the enzyme (imiglucerase) replacement therapy (ERT) is not able to stop the progression of the neurological involvement, while the substrate reduction therapy (SRT), performed by N-Butyldeoxynojirimycin (miglustat), is an alternative that should be evaluated. Two sisters, presenting the same genotype (R353G/R353G), were diagnosed as suffering from GD; one of them later developed neurological alterations identified by quantitative saccadic eye movements analysis. The aim of the study was to quantitatively measure the miglustat effects in this GD neurological patient. Eye movement analysis during subsequent controls was performed by estimating the characteristic parameters of saccadic main sequence. The study demonstrates that the SRT alone can be effective in GD3. Moreover, it confirms that quantitative eye movement analysis is able to precociously identify also slight neurological alterations, permitting more accurate GD classification.

Longterm follow-up of electroencephalographic and clinical findings of a case with Gaucher's disease type 3a

Among three recognised clinical phenotypes, type 3a Gaucher's disease is characterised by mild to severe systemic disease, neurological manifestations and myoclonic seizures. We report the long term clinical and electrophysiological follow-up of a 27-year old man with a diagnosis of type 3a Gaucher's disease, which was confirmed by bone marrow biopsy examination and leukocyte glucocerebrosidase level measurement. His neurological examination was normal throughout the follow-up period. EEG examination, recorded five days after the first seizure, revealed generalised nonrhythmic paroxysmal rapid spikes with occipital predominance increased by photic stimulation and normal background activity. The frequency of seizures increased from 3-4/year to 1-2/month within a follow-up period of 12 years and a repeat EEG examination on the eight year of diagnosis revealed additional background slowing. A giant potential was obtained in somatosensory evoked potential (SEP) examination. EEG findings of this case demonstrate a specific pattern with rapid spike activity, photosensitivity, eye closure sensitivity and gradual background slowing.

Congenital ocular motor apraxia associated with myopathy, external hydrocephalus and NADH dehydrogenase deficiency

Congenital ocular motor apraxia (COMA), first described by Cogan [Trans Am Acad Ophthalmol Otolaryngol 1952;56:853-862], is a rare disorder characterized by impairment of voluntary and optically induced horizontal eye movements and compensatory head thrust. The causes and pathogenesis of COMA are poorly understood. It frequently occurs in association with other neurologic abnormalities including non-progressive congenital disorders of the central nervous system (CNS), various systemic diseases and chromosomal alterations. Here, we report the case of a 6-month-old girl with psychomotor retardation, myopathy and clinical features of COMA, associated with external hydrocephalus and mitochondrial dysfunction (partial deficiency of the respiratory-chain enzyme NADH dehydrogenase). In view of this finding, we recommend that tests to characterize patients with COMA should include determination of blood levels of lactic and pyruvic acid.

Intermittent horizontal saccade failure ('ocular motor apraxia') in children

BACKGROUND

Ocular motor apraxia (OMA) in childhood is a poorly understood condition involving a failure of horizontal saccades. OMA is thought to be rare but the literature indicates wide clinical associations. OMA is often identified by abnormal head movements, but failure of reflexive quick phases has been reported in all but a few patients. The extent of this oculomotor disorder was examined in a large group of children with diverse clinical backgrounds.

METHODS

The degree of quick phase failure during horizontal vestibular and optokinetic nystagmus was measured using DC electro-oculography and video in 74 affected children, aged 17 days to 14 years.

RESULTS

All children showed an intermittent failure of nystagmic quick phases, except for total failure in one case. Other visuomotor abnormalities were common including saccadic hypometria (85%), low gain smooth pursuit (70%), neurological nystagmus (28%), strabismus (22%), and vertical abnormalities (11%). Non-ocular abnormalities were common including infantile hypotonia (61%), motor delay (77%), and speech delay (87%). There was a wide range of clinical associations including agenesis of the corpus callosum, Joubert syndrome, Dandy-Walker malformation, microcephaly, hydrocephalus, vermis hypoplasia, porencephalic cyst, megalocephaly, Krabbe leucodystrophy, Pelizaeus Merzbacher disease, infantile Gaucher disease, GM1 gangliosidosis, infantile Refsum's disease, propionic acidaemia, ataxia telangiectasia, Bardet-Biedl syndrome, vermis astrocytoma, vermis cyst, carotid fibromuscular hypoplasia, Cornelia de Lange syndrome, and microphthalmos. Perinatal and postnatal problems were found in 15% including perinatal hypoxia, meningitis, periventricular leucomalacia, athetoid cerebral palsy, perinatal septicaemia and anaemia, herpes encephalitis, and epilepsy. Only 27% were idiopathic.

CONCLUSION

Quick phase failure is a constant feature of OMA, whereas abnormal head movements were detected in only about half, depending on the underlying diagnosis. This oculomotor sign is better described as an intermittent saccade failure rather than as a true apraxia. It indicates central nervous system involvement, has wide clinical associations, but it is not a diagnosis.

Clinical diagnosis and diagnostic criteria of progressive supranuclear palsy (Steele-Richardson-Olszewski syndrome)

Progressive supranuclear palsy (PSP) is characterized clinically by supranuclear gaze palsy, neck dystonia, parkinsonism, pseudobulbar palsy, gait imbalance with frequent falls and frontal lobe-type dementia. In the advanced typical case, when supranuclear gaze palsy and other main features are present diagnosis is relatively easy. Diagnostic problems, though, are frequent in the early stages due to the variable clinical presentation and in those atypical cases in which gaze palsy does not develop or that present as a severe dementia disorder or as an isolated akinetic-rigid syndrome. In this review we summarize the clinical features of PSP and emphasize those aspects helpful in the differential diagnosis with Parkinson's disease and other motor and cognitive disorders that can pose difficult diagnostic problems. Clinical diagnostic criteria are also discussed and modifications of those currently in used are proposed.

Hydrocephalus, corneal opacities, deafness, valvular heart disease, deformed toes and leptomeningeal fibrous thickening in adult siblings: a new syndrome associated with beta-glucocerebrosidase deficiency and a mosaic population of storage cells

We describe three adult siblings with communicating hydrocephalus, corneal opacities, deafness, valvular heart disease, and deformed toes associated with glucosylceramide (glc-cer)-beta-glucosidase deficiency. The common manifestations of Gaucher disease were not evident. Supranuclear gaze palsies characteristic of type 3 were noted from early childhood, although the major signs were undeveloped until early adult life. Autopsy disclosed thickened leptomeninges with perivascular fibrosis, non-rheumatic calcified aortic and mitral stenosis with marked fibrosis, and mild infiltration of Gaucher cells in the reticuloendothelial organs. In contrast to the slight accumulation of glc-cer in the liver and spleen, the activity of glc-cer-beta-glucosidase was markedly decreased in the tissues, as much as in a patient with type 2 Gaucher disease. Common mutations were not found in the glucocerebrosidase gene.

Gaucher patients with oculomotor abnormalities do not have a unique genotype

Sixteen non-Ashkenazic American children with Gaucher disease who demonstrate slowing of the horizontal saccades are described. Attempts to correlate this specific clinical phenotype with a unique genotype were unsuccessful. Focusing on the three most common mutations, at least five different genotypes were present in these patients. Children with this isolated oculomotor abnormality generally had a diffusely slowed background on EEG, but an otherwise normal neurologic examination, and exhibited earlier and more severe systemic manifestations and mortality. This study emphasizes the need for careful sequential neuro-ophthalmologic examinations in Gaucher patients and the need for caution in attempting to make clinical predictions regarding the course of Gaucher disease on the basis of current DNA mutational analysis.

Late-infantile Gaucher disease in a child with myoclonus and bulbar signs: neuropathological and neurochemical findings

Clinical, neurochemical and neuropathological findings on a case of late-infantile Gaucher disease with oculomotor apraxia, progressive myoclonus and prominent bulbar signs are reported. There was a marked increase in glucosylceramide in cerebral cortex and cerebellum; the increase was more in the range of that seen in the Norrbottnian type III than in type II Gaucher disease. Cerebral cortical changes were characterized by a band-like intraparenchymal accumulation of Gaucher cells in lamina IV with an accompanying astrogliosis. In the cerebellum, a focal severe loss of granule cells and a global loss of dentate nucleus neurons was recorded. Milder changes were seen in thalamus and brain stem where perivascular accumulation of Gaucher cells was present in all regions. The cerebral cortical changes resembled those seen in type II Gaucher disease and was much more marked than in the Norrbottnian type III, whereas the changes in the dentate nucleus were more severe than in both type II and type III. The phenotypic variability with different patterns of clinical symptoms and neuropathological changes in neuronopathic Gaucher disease is discussed.

Intermittent vertical supranuclear ophthalmoplegia and ataxia

A 6-year-old girl is described with a history of episodes of severe ataxia precipitated by fever since the age of 11 months and in whom mental and physical development was otherwise normal. The ataxia was associated with a complete vertical supranuclear ophthalmoplegia and normal horizontal eye movements. After resolution of the attack she had no abnormal movement of her limbs or clinical evidence of ophthalmoplegia, though electro-oculograms showed a persistent mild deficit of vertical saccades. In between the attacks hyperglycinuria, an elevated plasma glycine level (687 mumol L(-1], and negative screening for organic aciduria suggest that she may have nonketotic hyperglycinaemia. To our knowledge, intermittent vertical supranuclear ophthalmoplegia and ataxia in a normally developing child has not been reported previously.

Oculomotor apraxia: the presenting sign of Gaucher disease

Oculomotor apraxia may be idiopathic or a symptom of a variety of diseases. In Gaucher disease, oculomotor deficit is characterized by a failure of volitional horizontal gaze with preservation of vertical movements. We present 2 sisters, 6 1/2 and 5 1/2 years of age, in whom the presenting sign was oculomotor apraxia. Oculomotor apraxia has not been previously reported as the presenting manifestation of Gaucher disease.

Congenital ocular motor apraxia. Case reports and literature review

Two children with congenital ocular motor apraxia (C-OMA) associated with congenital malformations of the central nervous system (CNS) are presented, and the literature is reviewed. C-OMA is an abnormality of ocular motility characterized by defective or absent voluntary horizontal gaze, associated with a characteristic head thrust. Although not rare, it is infrequently recognized. C-OMA is not a specific disease entity, but a sign. It may be associated with other static congenital CNS disorders and must be distinguished from acquired ocular motor apraxias (A-OMA) seen in progressive brain disorders and in certain serious systemic diseases. Therefore, when movements typical of C-OMA are observed, a careful systemic and neurologic examination should be performed, including immunoglobulin screening, cranial computerized tomography scanning, and adequate follow-up. Close relatives also should be examined.

Gaucher disease--Norrbottnian type. Ocular abnormalities

Ocular abnormalities in 22 patients with the Norrbottnian type of Gaucher disease are reported. During their first 10 years of life 10 patients had a horizontal gaze abnormality simulating congenital ocular motor apraxia. Examination showed signs of supranuclear oculomotor disturbances in several of them. Thirteen patients had squint secondary to weakness of the abductor muscles; 8/21 examined patients exhibited white retinal infiltrates, which mostly appeared after splenectomy; 8/19 examined patients had myopia. Except for the retinal changes, no connection was found between the abnormalities and the severity of the disease.

Gaucher disease--Norrbottnian type. I. General clinical description

We report follow-up studies of 22 cases of the Norrbottnian type of Gaucher disease ("type III"). The series was divided into 2 main groups of families depending on their birth province (Norrbotten, Västerbotten). The distribution and types of organ manifestations and complications were the same in both groups, each of which was considered to be genotypically homogeneous. The severity of the clinical symptoms and signs and the course of the disease differed markedly not only between families but also between siblings. Splenectomy accelerated deterioration, particularly with regard to skeletal and central nervous system manifestations. On a clinical basis it is concluded that the Norrbottnian type of Gaucher disease, which has now been diagnosed in about 40 cases, is probably due to a unique mutation which may have happened several hundred of years ago in northern Sweden.