UNASSIGNED: Landau-Kleffner syndrome (LKS) is a rare epileptic encephalopathy characterized by language regression and abnormal electroencephalogram (EEG) patterns. This case report highlights the importance of early recognition and intervention in LKS, as well as the challenges in diagnosis and management due to its varied clinical manifestations.
UNASSIGNED: An 8-year-old girl presented with delayed speech, suspected hearing loss, and regression in language skills. Diagnostic tests revealed mild sensorineural hearing loss and EEG abnormalities consistent with LKS. The patient underwent speech therapy and received pharmacological treatment with valproic acid, resulting in significant improvements in language function.
UNASSIGNED: This case report provides insights into the typical features of LKS, including language regression and EEG abnormalities. It also highlights uncommon findings such as sensorineural hearing loss and mild intellectual delay. The multidisciplinary approach involving neurology, audiology, speech therapy, and education is crucial in the diagnosis and management of LKS.
UNASSIGNED: Early recognition and intervention, along with tailored pharmacological approaches and a multidisciplinary care approach, are essential in managing LKS. Further research is needed to better understand the pathophysiology, natural history, and optimal treatment of LKS, aiming to improve long-term outcomes for affected children and their families.

BACKGROUND: Most children with Benign epilepsy with centro-temporal spikes (BECTS) undergo remission during late adolescence and do not require treatment. In a small group of patients, the condition may evolve to encephalopathic syndromes including epileptic encephalopathy with continuous spike-and-wave during sleep (ECSWS), or Landau-Kleffner Syndrome (LKS). Development of prediction models for early identification of at-risk children is of utmost importance.
OBJECTIVE: To develop a predictive model of encephalopathic transformation using data-driven approaches, reveal complex interactions to identify potential risk factors.
METHODS: Data were collected from a cohort of 91 patients diagnosed with BECTS treated between the years 2005-2017 at a pediatric neurology institute. Data on the initial presentation was collected based on a novel BECTS ontology and used to discover potential risk factors and to build a predictive model. Statistical and machine learning methods were compared.
RESULTS: A subgroup of 18 children had encephalopathic transformation. The least absolute shrinkage and selection operator (LASSO) regression Model with Elastic Net was able to successfully detect children with ECSWS or LKS. Sensitivity and specificity were 0.83 and 0.44. The most notable risk factors were fronto-temporal and temporo-parietal localization of epileptic foci, semiology of seizure involving dysarthria or somatosensory auras.
CONCLUSIONS: Novel prediction model for early identification of patients with BECTS at risk for ECSWS or LKS. This model can be used as a screening tool and assist physicians to consider special management for children predicted at high-risk. Clinical application of machine learning methods opens new frontiers of personalized patient care and treatment.

OBJECTIVE: We aimed to determine the incidence and prevalence of LKS in Japanese children.
METHODS: A questionnaire was sent to all 3004 Japanese hospitals that have a department of pediatrics. The questionnaire asked for the number of first-visit LKS patients and LKS patients who were followed up at or visited their clinic during the past one year Vital statistics of the same year (2008) published by Ministry of Health, Labor and Welfare, Japan were referenced to calculate the estimated incidence and prevalence of LKS among Japanese children.
RESULTS: Chiefs of 1562 pediatric departments answered our inquiry (51.9% of returns). Six chiefs had one new LKS patient, aged 6-14 years. Thirty two patients with LKS were followed in the same period. The number of children with LKS less than 20 years of age who needed medical care was at least 23 and at most 31. Vital statistics of Japan 2009 revealed that the population of children aged 5-14 years was 11,861,464 and that aged 5-19 years was 18,007,968.
CONCLUSIONS: The number of the first-visit LKS patients was 6 in a year. We estimated the incidence of LKS in the 5- to 14-years-old Japanese population as about 1 in 978,000. The number of LKS patients aged 5-19 was estimated to range from 44.2 to 59.6 among a population of 18,007,968. This means the prevalence of LKS under medical care is roughly one in 302,147-407,420 children aged 5-19. This study is the first epidemiological estimation of the incidence and prevalence of children with LKS in Japan or, for that matter, in any other area.
CONCLUSIONS: (1) Incidence of children with LKS aged 5-14 years was about 1 in a million in Japan. (2) Prevalence of children with LKS aged 5-19 and under medical care was one in about 300,000-410,000 in Japan. (3) This study constitutes the first epidemiological estimation of LKS in Japan.