ACUTE ATAXIA, TAKING PLACE AFTER ACUTE RESPIRATORY VIRAL INFECTION IN 2 Y. O. GIRL, AS A DEBUT NEUROLOGIC SIGN OF THE ANGELMAN SYNDROME

Abstract

Angleman syndrome (АS) – is a chromosomal syndrome, which is manifested through atypical autism with feeble minding, epilepsy, outrage of the speech development, movement disorders, ataxia, as well as special (happy) behavior of patients, combined with outbursts of laugh. The disease is caused by the mutation of 15q11.2–13 maternal locus or by the gene of UBE3A ubiquitinated complex. Such genes regulate the functional activity of hippocampus neurons, of olfactory bulbs, of the parastriate cortex, of the tentorium. We demonstrate the atypical AS case, which clinical presentation developed after acute respiratory viral infection with febrile temperature. The disease started with episodes of acute ataxia, interrupting daily activities of the child. Step by step the speech development was regressing – several words have fallen out, leaving the space for babbling sounds. Also appeared stereotypic movements of upper extremities (bending of arms in elbow joints, its retraction and joggling of hands), unmotivated laugh. Due to the nonrelevant starting presentation in the acute period following conditions were differentially diagnosed: 1) opsoclonus-myoclonus syndrome; 2) cerebral circulation diseases; 3) epilepsy with absences and atonic attacks; 4) paroxysmal dyskenisias and ataxias; 5) start of the neurodegenerative disease; 6) early childhood autism. Results of laboratory research allowed to exclude opsoclonus-myoclonus, the magnetic and resonance tomography and vessels research allowed to exclude the cerebrovascular pathology. Changes, revealed in the course of the videoelectroencephalographic monitoring, as well as anamnesis data (clinical symptoms after fever) allowed to narrow the diagnostic search; AS suspected. Provided the combination of ataxia with movement disorders, it was decided to carry out not molecular & genetic, but also micromatrix analysis, in order to exclude the channelopathy, as well as other genetic reasons. The method of polymerase chain reaction did not reveal changes, typical for AS. Anyway, the micromatrix analysis has revealed that the molecular karyotype has got spots with lost heterozygosis of locuses, containing genes, referred to the imprinting phenomena (UBE3A). In such a way, AS was confirmed.