developmental and epileptic encephalopathy, 18

Developmental and epileptic encephalopathy, 18 is a neurological condition that primarily affects brain development and is characterized by profound global developmental delay and seizures. Pathogenic variants in the SZT2 gene underlie the disorder, impairing the normal function of proteins important for neurological health. Typically, affected individuals present in infancy with motor challenges such as hypotonia and significant developmental impairment. Precise prevalence figures are not well established, reflecting the rarity and complexity of this condition.

Individuals with this condition almost universally exhibit profound global developmental delay and hypotonia, underscoring its significant impact on cognitive and motor functions. Seizures, including tonic seizures, bilateral tonic-clonic seizures with focal onset, and atypical absence seizures, are common and contribute to the overall clinical picture. Additional features reported in some cases include absent speech, as well as non-neurological findings such as oligohydramnios, polyhydramnios, and certain cardiac anomalies like aortic regurgitation and atrial septal defect. Not all individuals experience all these features, and severity varies considerably.

The condition arises from pathogenic variants in the SZT2 gene, which is expressed in the brain and plays a crucial role in normal neurological function. Disruption of this gene’s function leads to the developmental and epileptic features observed in affected individuals. It is inherited in an autosomal recessive pattern, meaning that an affected child inherits one altered copy of the gene from each carrier parent. Families are encouraged to consult genetic counseling to understand the implications and recurrence risks associated with this mode of inheritance.

Currently, management centers on supportive care and symptom control, with treatment plans tailored to the individual's unique needs. A multidisciplinary team is typically involved to address developmental delays, seizure management, and the monitoring of other clinical issues such as cardiac anomalies. In the absence of targeted treatments, patients are advised to work closely with their healthcare providers and pursue genetic counseling to explore all available supportive therapies.

Developmental and epileptic encephalopathy, 18 is a lifelong condition with a highly variable course. With current standards of care, many individuals benefit from periods of stabilization following early challenges, although the overall trajectory can vary widely. Outcomes described in medical literature continue to evolve as standards of care improve, and individual experiences differ depending on symptom severity and access to specialized services. Families often find it helpful to connect with genetic counselors and support groups for ongoing guidance and community connection.

Clinical trials are underway exploring new treatment approaches. Individuals interested in clinical trials can search ClinicalTrials.gov or consult their care team about eligibility.