When Baby’s giggles are not funny: seven years overlooked diagnosis in a case of gelastic seizures

L aughter actually has positive emotional effect. However, it could be pathologic when laughter is not related to emotion and occurs independent of a stimulus in the environment. We reported a 7-year-6-month old Thai boy who presented with ‘early giggles’ since the age of 2 months. Despite parental concerns, the symptoms were overlooked until seven years of age, when he developed complex partial seizures. An MRI study of the brain revealed a small ill defined lesion within the tuber cinereum that was compatible with hypothalamic hamartoma. We also reviewed and emphasized the characteristics of the pathologic laughing in infancy that should not have been ignored. Early diagnosis leads to appropriate counseling and proper seizure management. Common comorbidity such as precocious puberty and cognitive impairment or behavioral impediment should be followed up closely in long-term care.