title: A case series of histoplasmosis patients with elevated serum soluble interleukin-2 receptor levels.
abstract: Histoplasmosis is a common endemic mycosis that is usually asymptomatic but occasionally results in severe illness. Histoplasmosis and its causative agent, Histoplasma capsulatum, are found worldwide but rarely in Japan. In recent years, however, the number of histoplasmosis patients in Japan has increased. In addition, to our knowledge, there are no previous reports of increased serum soluble interleukin-2 receptor (sIL-2R) levels in patients with histoplasmosis. We report a case series of histoplasmosis in three Japanese temporary workers in Manzanillo, Mexico. All three patients developed a persistent high fever and general fatigue. Laboratory tests showed increased C-reactive protein levels and mild liver dysfunction. All patients also showed increased soluble interleukin-2 receptor (sIL-2R) levels. Chest computed tomography revealed multiple nodules in both lung fields. All patients were positive for serum anti-Histoplasma antibodies, and two patients were positive for Histoplasma on polymerase chain reaction tests. After treatment that included antifungals, their conditions gradually improved and laboratory data normalized. Although one patient developed respiratory failure, this patient recovered with antifungal therapy in combination with methylprednisolone. Serum sIL-2R levels in all patients gradually declined to normal levels, indicating their recovery from Histoplasma infection. From our experience with these patients, sIL-2R levels may be a useful biomarker for patients with histoplasmosis.
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Hirayama
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan. Electronic address: takahiro-takazono@nagasaki-u.ac.jp.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Takazono
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Kazuma
authors.initials: K
authors.lastname: Iwata
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Senju
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Takaharu
authors.initials: T
authors.lastname: Shimazaki
authors.affiliation: Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; Infection Control and Education Center, Nagasaki University Hospital, Nagasaki, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Tashiro
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Tomomi
authors.initials: T
authors.lastname: Saijo
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tanaka
authors.affiliation: Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Nakamura
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Imamura
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Kojiro
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Taiga
authors.initials: T
authors.lastname: Miyazaki
authors.affiliation: Infection Control and Education Center, Nagasaki University Hospital, Nagasaki, Japan.
authors.forename: Misuzu
authors.initials: M
authors.lastname: Tsukamoto
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Division of Infectious Diseases Department of Internal Medicine Nagasaki Rosai Hospital, Nagasaki, Japan.
authors.forename: Akitsugu
authors.initials: A
authors.lastname: Furumoto
authors.affiliation: Department of Infectious Diseases, Nagasaki University Hospital, Nagasaki, Japan; Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan.
authors.forename: Konosuke
authors.initials: K
authors.lastname: Morimoto
authors.affiliation: Medical Mycology Research Center, Chiba University, Chiba, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Muraosa
authors.affiliation: Juko Memorial Nagasaki Hospital, Nagasaki, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Matsubara
authors.affiliation: Department of Laboratory Medicine, Nagasaki University Hospital, Nagasaki, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Yanagihara
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan; Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mukae
authors.affiliation: Medical Mycology Research Center, Chiba University, Chiba, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Kamei
authors.affiliation: Second Department of Internal Medicine, Nagasaki University Hospital, Nagasaki, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kohno
authors.affiliation: Department of Infectious Diseases, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; Infection Control and Education Center, Nagasaki University Hospital, Nagasaki, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Izumikawa
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism; D006660:Histoplasmosis / Q000097:blood* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007564:Japan / Q000208:ethnology; D008297:Male; D008800:Mexico; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000097:blood*; D000076082:Travel-Related Illness
chemical_list: D015415:Biomarkers; D015375:Receptors, Interleukin-2; D002097:C-Reactive Protein
keywords: Histoplasmosis; Japan; Soluble interleukin-2 receptor (sIL-2R)