Paroxysmal tonic upgaze presenting as a clinical isolated syndrome

Paroxysmal tonic upgaze accompanied by occipital discharge on electroencephalography: a case report and literature review

Background

Paroxysmal tonic upgaze (PTU) is an infantile-onset paroxysmal neurological disorder that is characterized by episodes of sustained conjugate upward eye deviation. The paroxysmal abnormal eye movements need to be differentiated from seizures. We report a case of PTU with occipital discharge on electroencephalography (EEG), which made the diagnosis more complicated.

Case presentation

A 6-month-old girl presented with paroxysmal upward deviation or left strabismus of the eyes, with a bowed head, lowered jaw, raised eyebrows, closed lips, and slight grin. Each episode lasted for a few seconds, and episodes occurred multiple times per day. EEG showed spike waves in the right occipital region, and the girl was initially misdiagnosed with epilepsy. After further analysis using video EEG, we corrected her diagnosis as PTU and stopped the administration of an antiepileptic drug.

Conclusion

PTU accompanied by discharge on EEG may lead to a misdiagnosis. Video EEG monitoring, and especially the analysis of EEG traces synchronized with attacks, can provide evidence to distinguish between seizures and non-epileptic events.

Identification of Two de novo Variants of CACNA1A in Pediatric Chinese Patients With Paroxysmal Tonic Upgaze

Objective: Investigate the clinical manifestations and genotypes of paroxysmal tonic upgaze (PTU) in Chinese children. Patients and Methods: We report the clinical manifestations and genetic test results of four pediatric PTU patients in China. Recent articles on PTU cases are also summarized and analyzed. Results: The onset age of all four cases was at early infancy, and they presented as episodic binocular upward gaze with mild growth retardation. Two patients each carried a novel de novo variant in the CACNA1A gene, c.4046C>T (p.R1349X), and c.4415C>T (p.S1472L). Conclusion: Patients with infantile-onset paroxysmal binocular upward gaze should be considered to diagnose as PTU.

Paroxysmal tonic upgaze: A heterogeneous clinical condition responsive to carbonic anhydrase inhibition

BACKGROUND

Paroxysmal tonic upgaze (PTU), defined as an involuntary upward movement of the eyes, has been considered as a benign phenomenon but may also be associated with ataxia and developmental delay.

METHODS

We report eight children with PTU; six of them also exhibiting symptoms of ataxia and/or developmental delay. Treatment with carbonic anhydrase inhibition was offered to children with persisting and/or severe forms.

RESULTS

Whole-exome sequencing and genome-wide array analysis (n = 7) did not reveal mutations in the three known genes associated with PTU (CACNA1A, GRID2, SEPSECS), whereas by MLPA a heterozygous deletion of exon 31 of the CACNA1A gene could be detected in one patient, her mother and two further family members. Further exome and array analysis showed no recurrent variants in potentially novel PTU-related genes in more than one patient. A de novo variant at a highly conserved position in the SIM1 gene was detected in one patient, for which a pathogenic effect could be speculated. Carbonic anhydrase inhibition was started in five children and proved at least partially effective in all of them.

CONCLUSION

Irrespective of the clinical background and the molecular basic mechanism of PTU, therapeutic carbonic anhydrase inhibition was effective in all five children (acetazolamide, n = 3; sultiame, n = 2) who received this treatment.

Transient benign paroxysmal movement disorders in infancy

This review summarizes the current empirical and clinical literature on benign paroxysmal movement disorders in infancy most relevant to practitioners. Paroxysmal benign movement disorders are a heterogeneous group of movement disorders characterized by their favourable outcome. We pay special attention to the recognition and management of these abnormal motor conditions strongly suggestive of epileptic disorders. They include: neonatal jitteriness; benign neonatal sleep myoclonus; benign paroxysmal tonic upgaze; paroxysmal tonic downgaze, benign paroxysmal torticollis and benign polymorphous movement disorder of infancy.

Paroxysmal tonic upgaze in normal children: a case series and a review of the literature

The purpose of this review was to update the clinical characteristics of paroxysmal tonic upgaze in neurodevelopmentally normal children. We made the diagnosis (between 2008 and 2010) in 8 infants referred to us with suspected epilepsy. We found 38 further cases in the literature. In the 46 children (29 boys and 17 girls) tonic upward ocular deviation was first noticed between the age of 2 weeks and 90 months (median: 9 months). This tendency persisted for between 1 and 48 months (median: 7 months). The duration of paroxysmal events was highly variable: brief events lasted between 3 s and 10 min in 50% of the cases, intermediate events between 5 s and 30 min and long events between 10 s and 2 h. The frequency ranged from one every 3 months to 10 per day. In 15 children the episodes of upward deviation of the eyes were associated with an impaired movement coordination. In 2 further children an impaired movement coordination was noted during febrile illnesses. The results of this review in normal children characterize the entity as follows: onset under 2 years of age, a small predilection for the male gender, eventual improvement and recovery, and impaired movement coordination.

Idiopathic paroxysmal tonic upward gaze

Paroxysmal tonic upward gaze constitutes a neuro-ophthalmologic syndrome characterized by episodes of sustained conjugate upward deviation of the eyes, normal horizontal gaze, and ataxia. Its pathogenesis is unknown, and the etiology is heterogeneous. The prognosis is variable. We present a case of "idiopathic paroxysmal tonic upward gaze" with a positive clinical course and spontaneous remission.