title: A case of vildagliptin-induced interstitial pneumonia.
abstract: A 65-year-old Japanese male with type 2 diabetes mellitus was admitted to our hospital with a productive cough and worsening dyspnea. He had started receiving vildagliptin, which is one of the dipeptideylpeptidase-4 (DPP-4) inhibitors, several days before the appearance of his symptoms. Laboratory findings revealed markedly elevated levels of immunoglobulin E and Krebs von den Lungen-6. Chest computed tomography revealed ground-glass opacity with irregular reticulation throughout both lungs. Biopsy specimens by transbronchial lung biopsy showed subacute interstitial pneumonia and an organizing pneumonia pattern with acute alveolar injury. The drug lymphocyte stimulation test showed a positive result for vildagliptin. Withdrawal of vildagliptin and administration of glucocorticoid treatment improved his respiratory condition and radiological findings. Therefore, we diagnosed the patient with vildagliptin-induced interstitial pneumonia based on both his clinical course and pathological findings. Interstitial pneumonia as a side effect of vildagliptin is rare. It may be necessary to monitor the respiratory condition of patients upon administration of DPP-4 inhibitors until further evidence is obtained.
authors.affiliation: Division of Pulmonary Medicine, Tokyo Metropolitan Hiroo Hospital, 2-34-10 Ebisu Shibuya-ku, Tokyo, 150-0013, Japan; Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan.
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Kuse
authors.affiliation: Division of Pulmonary Medicine, Tokyo Metropolitan Hiroo Hospital, 2-34-10 Ebisu Shibuya-ku, Tokyo, 150-0013, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Abe
authors.affiliation: Division of Pulmonary Medicine, Tokyo Metropolitan Hiroo Hospital, 2-34-10 Ebisu Shibuya-ku, Tokyo, 150-0013, Japan.
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Kuribayashi
authors.affiliation: Division of Pulmonary Medicine, Tokyo Metropolitan Hiroo Hospital, 2-34-10 Ebisu Shibuya-ku, Tokyo, 150-0013, Japan.
authors.forename: Minoru
authors.initials: M
authors.lastname: Inomata
authors.affiliation: Division of Pulmonary Medicine, Tokyo Metropolitan Hiroo Hospital, 2-34-10 Ebisu Shibuya-ku, Tokyo, 150-0013, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Saito
authors.affiliation: Division of Diagnostic Pathology, Itabashi Chuo Medical Center, 2-12-7 Azusawa Itabashi-ku, Tokyo, 174-0051, Japan.
authors.forename: Yuh
authors.initials: Y
authors.lastname: Fukuda
authors.affiliation: Department of Pulmonary Medicine and Oncology, Graduate School of Medicine, Nippon Medical School, 1-1-5 Sendagi Bunkyo-ku, Tokyo, 113-8602, Japan.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Gemma
keywords: BAL, bronchoalveolar lavage; CT, computed tomography; DLST, drug lymphocyte stimulation tests; DPP-4 inhibitor; DPP-4, dipeptideylpeptidase-4; Drug-induced lung injury; FVC, forced vital capacity; IPAF, interstitial pneumonia with autoimmune features; IgE, immunoglobulin E; KL-6, Krebs von den Lungen-6; PFT, pulmonary function testing; T2DM, type 2 diabetes mellitus; TBLB, transbronchial lung biopsy; Vildagliptin