Abstract
In the Japanese Pediatric Guideline for the Treatment and Management of Asthma (JPGL), asthma occurring in infants under two years of age is defined as infantile asthma. The reason why asthma occurring in infants under two years of age is defined as infantile asthma is that airway narrowing can occur easily in 1 year old infants as well as infants under 1 year of age because of the anatomical and physiological characteristics of the respiratory system at this age. In addition, 60% of children with asthma develop asthma by their second birthdays. Therefore, in order to obtain a good prognosis, treatments and managements, including early intervention based on appropriate diagnosis at an early stage of the disease, are important. Towards this end, it is useful, for selecting the most appropriate treatment strategy, to classify infantile asthma into phenotypes such as allergen-induced asthma and virus-induced asthma. If "good" control can be maintained for three months or more by long-term management, step-down can be considered. However, earlier step-down can be considered for children generally diagnosed as having asthma, because the period after onset of asthma is short in infantile asthma and an early diagnosis is not always easy, with the possibility of over diagnosis. Furthermore, questionnaires, such as the Japanese Pediatric Asthma Control Program (JPAC) and a nighttime sleep diary are useful tools for long-term asthma management.
