A retrospective multicenter chart review was conducted with the objective of evaluating the hypothesis that certain cases diagnosed as tension-type headache (TTH) in pediatric neurology are not stress-related or central sensitization-related conditions but may mimic an autoimmune disorder of the dura mater. Of the 29,642 patient charts reviewed, 12,424 charts (42%) were excluded because of incomplete data and 17,218 cases were analyzed. For all the 29,642 charts, TTH or chronic daily headaches were diagnosed in 29.2% of cases. Among the 17,218 cases subjected to detailed diagnostic procedures, TTH was diagnosed in only 5%. In 7,044 cases, the initial diagnosis of TTH was changed to headache attributed to infection (87.4%), which was supported by the presence of meningeal signs, high antistreptolysin-O titers, and, in 46% of cases, magnetic resonance imaging (MRI)-detected thickening of the cranial dura mater. The initial diagnosis of migraine was confirmed in 87.7% of cases (8,034/9,162). In some cases of treatment-resistant pediatric recurrent headaches, which are initially diagnosed as TTH, a secondary type of headache may be suspected as the underlying cause. Usually this type of headache has streptococcal infection-related laboratory findings, the meninges as the site of the lesion, and meningism as the clinical presentation.