Severe childhood encephalopathy with dyskinesia and prolonged cognitive disturbances: evidence for anti-N-methyl-D-aspartate receptor encephalitis.

AIM: We report four cases of acquired severe encephalopathy with massive hyperkinesia, marked neurological and cognitive regression, sleep disturbance, prolonged mutism, and a remarkably delayed recovery (time to full recovery between 5 and 18mo) with an overall good outcome, and its association with anti-N-methyl-d-aspartate (anti-NMDA) receptor antibodies. METHOD: We reviewed the four cases retrospectively and we also reviewed the literature. RESULTS: Anti-NMDA receptor antibodies (without ovarian teratoma detected so far) were found in the two children tested in this study. INTERPRETATION: The clinical features are similar to those first reported in 1992 by Sebire et al.,(1) and rarely recognized since. Sleep disturbance was not emphasized as part of the disorder, but appears to be an important feature, whereas coma is less certain and difficult to evaluate in this setting. The combination of symptoms, evolution (mainly seizures at onset), severity, paucity of abnormal laboratory findings, very slow recovery, and difficult management justify its recognition as a specific entity. The neuropathological substrate may be anatomically close to that involved in encephalitis lethargica, in which the same target functions (sleep and movement) are affected but in reverse, with hypersomnolence and bradykinesia. This syndrome closely resembles anti-NMDA receptor encephalitis, which has been reported in adults and is often paraneoplastic.

Is benign myoclonic epilepsy of infancy truly idiopathic and generalized?

Benign myoclonic epilepsy of infancy is recognized as a generalized and idiopathic epilepsy by the International League Against Epilepsy. Unprovoked and reflex seizures have been reported in these patients. We describe a child diagnosed with benign myoclonic epilepsy of infancy, whose strictly unilateral and localized reflex myoclonias broaden the clinical spectrum of this idiopathic and generalized epileptic syndrome, and raise interrogations about its underlying pathophysiological mechanisms. [Published with video sequences].

Alexander disease: early presence of cerebral MRI criteria.

Alexander disease is a rare neurodegenerative disorder. Its most frequent subtype, the infantile form, is characterized by an early onset and a rapid neurological deterioration during the first months of life. Since the publication of cerebral radiological criteria in 2001, the disease has often been recognized by magnetic resonance imaging (MRI) findings. We report the case of a girl who at the age of 3 months presented with partial seizures and a normal neurological examination. MRI revealed the presence of a periventricular rim, extensive frontal white matter abnormalities, abnormalities of the basal ganglia and thalami and contrast enhancement involving optic chiasm, fornix, hypothalamus and mamillary bodies, corresponding to four of the five reported MRI criteria for Alexander disease. Additional MRI abnormalities not described so far were also observed. The diagnosis was confirmed by genetic analysis. This case illustrates that diagnostic MRI abnormalities of Alexander disease may be present at a very young age, long before the appearance of characteristic clinical signs. Early diagnosis by MRI allows prompt counselling of families.

Association of multiple vertebral hemangiomas and severe paraparesis in a patient with a PTEN hamartoma tumor syndrome. Case report.

The PTEN hamartoma tumor syndrome, manifestations of which include Cowden disease and Bannayan-Riley-Ruvalcaba syndrome, is caused by various mutations of the PTEN gene located at 10q23. Its major criteria are macrocephaly and a propensity to develop breast and thyroid cancers as well as endometrial carcinoma. Minor diagnostic criteria include hamartomatous intestinal polyps, lipomas, fibrocystic disease of the breasts, and fibromas. Mutations of PTEN can also be found in patients with Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum). The authors report the case of a 17-year-old girl who had a severe cyanotic cardiac malformation for which surgery was not advised and a heterozygous missense mutation (c.406T>C) in exon 5 of PTEN resulting in the substitution of cysteine for arginine (p.Cysl36Arg) in the protein, which was also found in her mother and sister. The patient presented in the pediatric emergency department with severe spastic paraparesis. A magnetic resonance imaging study of the spine showed vertebral hemangiomas at multiple levels, but stenosis and compression were maximal at level T5-6. An emergency T5-6 laminectomy was performed. The decompression was extremely hemorrhagic because the rapid onset of paraparesis necessitated prompt treatment, and there was no time to perform preoperative embolization. The patient's postoperative course was uneventful with gradual recovery. This represents the first report of an association of a PTEN mutation and multiple vertebral angiomas. The authors did not treat the remaining angiomas because surgical treatment was contraindicated without previous embolization, which in itself would present considerable risk in this patient with congenital cyanotic heart disease.

MECP2 mutant allele in a boy with Rett syndrome and his unaffected heterozygous mother.

Rett syndrome is a severe neurodevelopmental disorder affecting principally females and characterized by a normal postnatal development followed by stagnation and regression of acquired skills. We report a 4-year-old boy with a Rett syndrome phenotype and his unaffected mother both carrying a 44 bp truncating deletion mutation (c.1158del44 or p.388X) in the MECP2 gene. The presence of a skewed X inactivation in the mother provides a possible explanation for the absence of penetrance. The finding of a MECP2 mutation in an unaffected female complicates genetic counseling and further confirms that it is essential to look for mutations in the mothers of all patients with MECP2 mutations.

[Dizziness, syncope, and other consciousness loss in children]. / Malaises, syncopes et autres pertes de connaissance chez l'enfant.

Episodes of loss of consciousness and dizziness are frequent in children and adolescents. The causes are quite variable, most are harmless, some more worrisome. The correct diagnosis can most often be made by recognition of the characteristic sequence of the clinical symptoms and signs. History taking therefore is the most important diagnostic step, and additional work-up is only rarely required. We will review the clinical entities, whose knowledge is useful for pediatricians and general practitioners, since they belong, together with seizures, head injuries and headaches, to the neurological problems seen frequently in emergency consultations. They will be listed according to the age at which they are most often observed, and not according to frequency or severity. Seizure disorders have been excluded from the discussion, and only few and rare types of migraines have been included, since epilepsy and migraine are topics that will be discussed by other speakers during this symposium.

[How should a muscular disease be studied?]. / Comment investiguer une maladie musculaire?

Muscle diseases are an expanding field, mainly due to the progress in genetics and biochemistry. Evaluation starts with a thorough history of the patient's symptoms and signs. The leading clinical manifestations are weakness, atrophy, myalgia, fatigue, more rarely myotonia and in the child hypotonia or walking difficulty. A detailed family history might give clues to an underlying genetic etiology. Diagnostic workup begins with the measurement of serum creatine kinase. Electroneuromyography is an important investigation procedure which includes motor and sensory nerve conduction studies and concentric needle electromyography. Muscle biopsy is performed in all patients with clinical evidence of myopathy. A fine-needle technique is generally used, more often than a surgical biopsy. Molecular analysis of candidate genes is becoming a major diagnostic tool in many muscle disorders. Muscle imaging, in particular MR, provides diagnostic and follow-up information, especially in dystrophic, metabolic and inflammatory myopathies. Exercise testing can be useful in some metabolic myopathies. There is no standard protocol for the choice and course of investigations which must always be based on a detailed clinical evaluation. It is important to establish a precise diagnosis in order to inform the patient about the nature and the evolution of the disease, the therapeutic options and to propose, when indicated, genetic counseling.

Epileptic falls and gait disturbance in two young children with a sharp wave focus at the vertex: a variant of benign partial epilepsy of childhood?

We describe two young children who presented with frequent falls and myoclonic jerks affecting the trunk and legs associated with a sharp and slow wave epileptic focus at the vertex. The initial neurological examination and brain magnetic resonance imaging were normal. Both patients had a persistent gait dysfunction, sometimes asymmetrical, fluctuating with the intensity of the epilepsy and the electroencephalogram abnormalities. The localization of the epileptic focus at the vertex, corresponding to the motor control of the legs and trunk, can explain this peculiar semiology. The seizures were difficult to treat, but one patient is currently in remission. Although epileptic falls are most often a feature of severe epilepsies of childhood, we think that these two patients present a variant of benign partial epilepsy of childhood.

Early onset and rapidly progressive subacute sclerosing panencephalitis after congenital measles infection.

UNLABELLED: We report an 18-month-old girl with rapidly progressive subacute sclerosing panencephalitis, whose non immunised mother had measles at the time of delivery. The patient presented with repetitive episodes of myoclonic jerks of the head and arms, followed by a drop of head and trunk with frequent falls. EEG, CSF studies and MRI confirmed the diagnosis. Despite therapy with isoprinosine and valproate, seizure activity continued and she became vegetative within 2 months, with severe spasticity and swallowing difficulties, and died at the age of 28 months. Early age of onset and rapid progression were most likely related to haematogenous in utero acquisition of the measles virus prior to delivery, as well as immaturity of neuronal and immune systems. CONCLUSION: this case emphasises the importance of a high measles vaccine coverage in the population in order to prevent the risk of disease in general and, in particular, gestational measles.

A recessive form of central core disease, transiently presenting as multi-minicore disease, is associated with a homozygous mutation in the ryanodine receptor type 1 gene.

Multi-minicore disease is an autosomal recessive congenital myopathy characterized by the presence of multiple, short-length core lesions (minicores) in both muscle fiber types. These lesions being nonspecific and the clinical phenotype being heterogeneous, multi-minicore disease boundaries remain unclear. To identify its genetic basis, we performed a genome-wide screening in a consanguineous Algerian family in which three children presented in infancy with moderate weakness predominant in axial muscles, pelvic girdle and hands, joint hyperlaxity (hand involvement phenotype), and multiple minicores. We mapped the disease to chromosome 19q13 in this family and, subsequently, in three additional families showing a similar phenotype, with a maximum LOD score of 5.19 for D19S570. This locus was excluded in 16 other multi-minicore disease families with predominantly axial weakness, scoliosis, and respiratory insufficiency ("classical" phenotype). In the Algerian family, we identified a novel homozygous missense mutation (P3527S) in the ryanodine receptor type 1 gene, a positional candidate gene responsible for the autosomal dominant congenital myopathy central core disease. New muscle biopsies from the three patients at adulthood demonstrated typical central core disease with rods; no cores were found in the healthy parents. This subgroup of families linked to 19q13 represents the first variant of central core disease with genetically proven recessive inheritance and transient presentation as multi-minicore disease.