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: K Kamoi, I Kurokawa, H Kasai, A Mizusawa, T Ebe, H Sasaki, Y Matuzuki, Y Seino, M Takahashi, K Togashi, H Miyamura, Y Sato, H Takato, H Kaneko
• Journal: Internal medicine (Tokyo, Japan) (Intern Med) Vol. 37 Issue 11 Pg. 950-4 (Nov 1998) ISSN: 0918-2918 [Print] Japan
• PMID: 9868958 (Publication Type: Case Reports, Journal Article)

Chemical References

• Biomarkers, Tumor
• Vasopressins
• Sodium

Topics

• Aged
• Antineoplastic Combined Chemotherapy Protocols (therapeutic use)
• Biomarkers, Tumor (blood)
• Biopsy
• Bronchoscopy
• Carcinoma, Small Cell (complications, diagnosis, therapy)
• Follow-Up Studies
• Humans
• Hyponatremia (etiology, metabolism, therapy)
• Inappropriate ADH Syndrome (complications)
• Lung Neoplasms (complications, diagnosis, therapy)
• Magnetic Resonance Imaging
• Male
• Osmosis
• Radiotherapy, Adjuvant
• Sodium (blood)
• Tomography, X-Ray Computed
• Vasopressins (blood, metabolism)