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Vol 33, No 61 (2023)
Review paper
Published online: 2024-03-28

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Unraveling the complexities of CDKL5 deficiency disorder: Is an emerging treatment on the horizon?

Klaudia Bartoszewicz1, Barbara Steinborn21
DOI: 10.5603/cne.98938
Neurol Dziec 2023;33(61):35-40.


Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a developmental and epileptic encephalopathy in which epilepsy and impaired development are prominent features. Previously, CDD was considered a variant of Rett syndrome (Hanefeld variant). However, it is now recognized as an independent clinical entity. It is characterized by early-onset epilepsy, typically occurring within 3 months of age in majority of cases and presenting with polymorphic seizures. Severely impaired development leads to only a small percentage of affected patients achieving independent walking. Other notable clinical features include cortical visual impairment, sleep disturbances, stereotypical hand movements, hypotonia, gastrointestinal problems, scoliosis and respiratory tract infections.  The management of epilepsy in CDD is highly demanding due to its refractory nature. The results of conventional antiseizure management have been disappointing, exhibiting minimal or transient clinical effects. Alternative treatments like the ketogenic diet and vagus nerve stimulation have shown limited efficacy. However, new treatment options, such as ganaxolone are emerging and the results seem promising. Further research is needed to explore the potential of other treatments such as soticlestat, fenfluramine and cannabidiol, particularly in larger cohorts.             CDD is a multifaceted disorder and its underlying mechanisms remain incompletely elucidated. Further research is needed to better understand the pathological processes of the disorder and to develop more effective treatments for individuals with CDD.  Healthcare professionals should be aware of the clinical symptoms and challenges associated with CDD to provide appropriate care and support to individuals affected by this complex disorder.

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