Yasunori Enomoto1, Yutaro Nakamura1, Noriyuki Enomoto1, Tomoyuki Fujisawa1, Naoki Inui2, Takafumi Suda3. 1. Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Japan. 2. Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Japan; Department of Clinical Pharmacology and Therapeutics, Hamamatsu University School of Medicine, Japan. 3. Second Division, Department of Internal Medicine, Hamamatsu University School of Medicine, Japan. Electronic address: suda@hama-med.ac.jp.
Abstract
BACKGROUND: The number of reports concerning Japanese herbal medicine (JHM)-induced pneumonitis has increased. However, comprehensive data are lacking in this regard, and the clinical characteristics of the disease remain unclear. METHODS: A literature review was performed using PubMed and Ichushi-Web-the database of the Japan Medical Abstracts Society-to identify articles published between 1996 and 2015 describing patients with JHM-induced pneumonitis. The final cohort included 73 patients in 59 articles (7 in English; 52 in Japanese). RESULTS: Among the various JHMs reported, sho-saiko-to was the most frequently used drug (26%), followed by sairei-to (16%), seishin-renshi-in (8%), and bofu-tsusyo-san (8%). These drugs commonly contain ougon (skullcap) and kanzo (liquorice). The mean age at pneumonitis diagnosis was 63.2 ± 15.5 years (range: 7-89 years). The male/female ratio was 44/29. Sixty-five patients (89%) developed pneumonitis within 3 months of beginning JHM treatment. Bilateral ground-glass attenuations on chest computed tomography, as well as lymphocytosis with a low CD4/CD8 T-cell ratio in bronchoalveolar lavage fluid, were common findings. Twenty-six patients (36%) recovered from the pneumonitis after simply discontinuing the causative JHM. However, the remainder required immunosuppressive therapy, and 13 patients (18%) received mechanical ventilation. Importantly, three patients (4%) did not survive, with two showing pathological diffuse alveolar damage upon autopsy. CONCLUSIONS: Clinicians should be cautious regarding JHM-induced pneumonitis, particularly when using drugs/ingredients known to cause this complication, and during the early treatment period. Although most events are non-severe, critical cases should be recognized.
BACKGROUND: The number of reports concerning Japanese herbal medicine (JHM)-induced pneumonitis has increased. However, comprehensive data are lacking in this regard, and the clinical characteristics of the disease remain unclear. METHODS: A literature review was performed using PubMed and Ichushi-Web-the database of the Japan Medical Abstracts Society-to identify articles published between 1996 and 2015 describing patients with JHM-induced pneumonitis. The final cohort included 73 patients in 59 articles (7 in English; 52 in Japanese). RESULTS: Among the various JHMs reported, sho-saiko-to was the most frequently used drug (26%), followed by sairei-to (16%), seishin-renshi-in (8%), and bofu-tsusyo-san (8%). These drugs commonly contain ougon (skullcap) and kanzo (liquorice). The mean age at pneumonitis diagnosis was 63.2 ± 15.5 years (range: 7-89 years). The male/female ratio was 44/29. Sixty-five patients (89%) developed pneumonitis within 3 months of beginning JHM treatment. Bilateral ground-glass attenuations on chest computed tomography, as well as lymphocytosis with a low CD4/CD8 T-cell ratio in bronchoalveolar lavage fluid, were common findings. Twenty-six patients (36%) recovered from the pneumonitis after simply discontinuing the causative JHM. However, the remainder required immunosuppressive therapy, and 13 patients (18%) received mechanical ventilation. Importantly, three patients (4%) did not survive, with two showing pathological diffuse alveolar damage upon autopsy. CONCLUSIONS: Clinicians should be cautious regarding JHM-induced pneumonitis, particularly when using drugs/ingredients known to cause this complication, and during the early treatment period. Although most events are non-severe, critical cases should be recognized.