The HIHARS-AA phenomenon – a rare state of consciousness induced by hyperventilation, a “mask” of absence epilepsy: literature review with a case report

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Abstract

HIHARS-AA (hyperventilation-induced high-amplitude rhythmic slowing with altered awareness) is a non-epileptic, age-dependent condition that can coexist with childhood absence epilepsy, clinically indistinguishably mimicking absence seizures. Without video-electroencephalographic monitoring, misinterpretation of this phenomenon leads to diagnostic errors and unnecessary polytherapy, whereas correct verification of the phenomenon allows for optimized treatment and seizure control. The authors present a literature review with a case report.

About the authors

A. A. Nurgaleeva

N.I.Pirogov Russian National Research Medical University, Ministry of Health of Russia

Email: Abramov-m-o@yandex.ru
Russian Federation, 1 Ostrovityanova St., Moscow 117997

V. M. Menshenin

I.M. Sechenov First Moscow State Medical University, Ministry of Health of Russia (Sechenovskiy University)

Email: Abramov-m-o@yandex.ru
Russian Federation, Build. 2, 8 Trubetskaya St., Moscow 119048

Mikhail O. Abramov

Svt. Luka’s Institute of Child and Adult Neurology and Epilepsy

Author for correspondence.
Email: Abramov-m-o@yandex.ru
ORCID iD: 0000-0001-5215-9548
Russian Federation, 9 Akademika Anokhina St., Moscow 119571

A. S. Petrukhin

N.I.Pirogov Russian National Research Medical University, Ministry of Health of Russia; Svt. Luka’s Institute of Child and Adult Neurology and Epilepsy

Email: Abramov-m-o@yandex.ru
ORCID iD: 0000-0001-9961-0199
Russian Federation, 1 Ostrovityanova St., Moscow 117997; 9 Akademika Anokhina St., Moscow 119571

References

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