title: A case of sarcoidosis with interstitial lung disease mimicking clinically amyopathic dermatomyositis and rapidly progressive interstitial lung disease.
abstract: Here, we report a patient with sarcoidosis who developed edematous erythema and interstitial lung disease. At the initial visit, clinically amyopathic dermatomyositis (CADM) with rapidly progressive interstitial lung disease (RP-ILD) was suspected because he had progressive dyspnea but no muscle weakness. The presence of anti-CADM-140/MDA5 autoantibodies was immediately assessed to facilitate a precise diagnosis, with negative results. Thereafter, skin and transbronchial lung biopsies revealed noncaseating granuloma with Langhans giant cells in both specimens, leading to a diagnosis of sarcoidosis. In this case, clinical features of skin and lung were unable to distinguish DM (including CADM) from sarcoidosis, but the lack of anti-CADM-140/MDA5 antibody was useful for differentiating CADM with RP-ILD mimicking sarcoidosis from bona fide sarcoidosis.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Shinji
authors.identifier: 0000-0002-6338-7367
authors.initials: S
authors.lastname: Sato
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Nogi
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Sasaki
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Naofumi
authors.initials: N
authors.lastname: Chinen
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Kiri
authors.initials: K
authors.lastname: Honda
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Eiko
authors.initials: E
authors.lastname: Saito
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Wakabayashi
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Chiho
authors.initials: C
authors.lastname: Yamada
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Tokai University School of Medicine, 142 Shimokasuya, Isehara 259-1193, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Suzuki