loading page

Ten years' experience of pediatric idiopathic interstitial pneumonia registration system in Japan.
  • Naotaka Tamai,
  • Goro Koinuma,
  • Kuniyuki Okada
Naotaka Tamai
National Center for Child Health and Development

Corresponding Author:[email protected]

Author Profile
Goro Koinuma
National Center for Child Health and Development
Author Profile
Kuniyuki Okada
Okada Children’s Clinic
Author Profile


Background: Pediatric idiopathic interstitial pneumonia (IIP) is a rare disease with no established diagnostic or therapeutic guidelines. Hydroxychloroquine (HCQ) has no indication for this disease and is contraindicated in patients under 6 years of age. The aim of this study was to evaluate the diagnostic procedure, and efficacy and safety of IIP treatment in Japan. Methods: The Japanese Society of Pediatric Pulmonology (JSPP) implemented a registration system from April 2010 to March 2020. The enrollment criteria were posted on the JSPP website, and e-mail requests for enrollment from physicians were accepted. Questionnaires were sent to investigate symptoms, laboratory findings, treatment effects, and outcomes. Results: Thirty-four patients were collected in a 10-year period. The age at onset ranged from 0 to 8 years. Genetic testing was performed in 29 cases, and mutations were found in 17 cases. Lung biopsies were performed in 16 patients, with nonspecific interstitial pneumonia being the most common cause. Twenty-eight patients received HCQ, 27 of whom were under 6 years of age at the start of treatment. The duration of HCQ treatment ranged from 1 month to 13 years, with no reports of retinopathy. Eighteen patients showed a good course of treatment with monotherapy with either steroids, HCQ, or a combination of both. Lung transplantation was reported in three cases. Six patients had died. Conclusion: This study demonstrated that half of the IIP patients were diagnosed by genetic testing. HCQ was used safely, including in patients under 6 years of age, with attention being paid to hypoglycemia.