title: Asymptomatic hyponatremia due to inappropriate secretion of antidiuretic hormone as the first sign of a small cell lung cancer in an elderly man.
abstract: A 72-year-old man was hospitalized with asymptomatic hyponatremia. Despite hyponatremia, urinary sodium excretion with urine osmolality exceeding plasma osmolality persisted. Plasma vasopressin levels were high and independent of plasma osmolality during hypertonic saline infusion. Computed tomography of the chest showed enlarged mediastinal and right hilar lymph nodes. Microscopically, a specimen of lymph nodes obtained by biopsy represented vasopressin-producing small cell lung carcinoma. Chemotherapy plus irradiation improved the hyponatremia. Thus, careful evaluation is necessary to determine the cause of hyponatremia disorders in elderly patients.
authors.affiliation: Department of Internal Medicine, Nagaoka Red Cross Hospital, Niigata.
authors.forename: K
authors.initials: K
authors.lastname: Kamoi
authors.forename: I
authors.initials: I
authors.lastname: Kurokawa
authors.forename: H
authors.initials: H
authors.lastname: Kasai
authors.forename: A
authors.initials: A
authors.lastname: Mizusawa
authors.forename: T
authors.initials: T
authors.lastname: Ebe
authors.forename: H
authors.initials: H
authors.lastname: Sasaki
authors.forename: Y
authors.initials: Y
authors.lastname: Matuzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Seino
authors.forename: M
authors.initials: M
authors.lastname: Takahashi
authors.forename: K
authors.initials: K
authors.lastname: Togashi
authors.forename: H
authors.initials: H
authors.lastname: Miyamura
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
authors.forename: H
authors.initials: H
authors.lastname: Takato
authors.forename: H
authors.initials: H
authors.lastname: Kaneko
mesh_terms: D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000097:blood; D001706:Biopsy; D001999:Bronchoscopy; D018288:Carcinoma, Small Cell / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D005500:Follow-Up Studies; D006801:Humans; D007010:Hyponatremia / Q000209:etiology* / Q000378:metabolism / Q000628:therapy; D007177:Inappropriate ADH Syndrome / Q000150:complications*; D008175:Lung Neoplasms / Q000150:complications / Q000175:diagnosis* / Q000628:therapy; D008279:Magnetic Resonance Imaging; D008297:Male; D009995:Osmosis; D018714:Radiotherapy, Adjuvant; D012964:Sodium / Q000097:blood; D014057:Tomography, X-Ray Computed; D014667:Vasopressins / Q000097:blood / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D014667:Vasopressins; D012964:Sodium