title: Yield of workup for patients with idiopathic presentation of the syndrome of inappropriate antidiuretic hormone secretion.
abstract: OBJECTIVE
  To determine the proportion of patients for whom the syndrome of inappropriate antidiuretic hormone secretion (SIADH) is the presenting symptom of an underlying disorder, to describe the yield of different diagnostic modalities for patients with SIADH and an unknown etiology, and to define patients for whom such a workup is indicated.
  
  
  METHODS
  A single center retrospective study including all patients diagnosed with SIADH without an apparent etiology in a large community hospital and tertiary center between 1.1.07 and 1.1.13. Two physicians reviewed every patient's medical file for predetermined relevant clinical data.
  
  
  RESULTS
  Eleven of the 99 patients without an apparent etiology for SIADH at presentation were found to have an underlying cause on workup. Yield of performed workup was low, with a pathology demonstrated on 0%-30.8% of tests according to the different modalities used. Patients with presumed idiopathic SIADH at presentation who were later found to have a specific etiology were younger than patients with true idiopathic SIADH, had a significantly shorter duration of hyponatremia prior to SIADH diagnosis, had higher urine osmolality and a clinical presentation suggestive of an undiagnosed disorder.
  
  
  CONCLUSIONS
  Our findings support a clinically-based approach to patients with idiopathic SIADH, rather than an extensive routine workup for all patients.
authors.affiliation: Medicine A, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address: Shepshelovich@yahoo.com.
authors.forename: Daniel
authors.initials: D
authors.lastname: Shepshelovich
authors.affiliation: Medicine A, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Chiya
authors.initials: C
authors.lastname: Leibovitch
authors.affiliation: Medicine A, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Alina
authors.initials: A
authors.lastname: Klein
authors.affiliation: Medicine A, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Shirit
authors.initials: S
authors.lastname: Zoldan
authors.affiliation: Statistical Consulting Unit, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Tzippy
authors.initials: T
authors.lastname: Shochat
authors.affiliation: Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Nephrology and Hypertension, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: Hefziba
authors.initials: H
authors.lastname: Green
authors.affiliation: Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Nephrology and Hypertension, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: Benaya
authors.initials: B
authors.lastname: Rozen-Zvi
authors.affiliation: Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Institute of Hematology, Davidoff Center, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Meir
authors.initials: M
authors.lastname: Lahav
authors.affiliation: Medicine A, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Institute of Hematology, Davidoff Center, Beilinson Hospital, Rabin Medical Center, Petach Tikva, Israel.
authors.forename: Anat
authors.initials: A
authors.lastname: Gafter-Gvili
mesh_terms: D000038:Abscess / Q000150:complications* / Q000175:diagnosis; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001650:Bile Duct Neoplasms / Q000150:complications / Q000175:diagnosis; D001927:Brain Diseases / Q000150:complications* / Q000175:diagnosis; D002277:Carcinoma / Q000150:complications / Q000175:diagnosis; D018288:Carcinoma, Small Cell / Q000150:complications / Q000175:diagnosis; D018281:Cholangiocarcinoma / Q000150:complications / Q000175:diagnosis; D003110:Colonic Neoplasms / Q000150:complications / Q000175:diagnosis; D005260:Female; D020042:Histiocytic Necrotizing Lymphadenitis / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000175:diagnosis / Q000209:etiology* / Q000378:metabolism; D016015:Logistic Models; D008171:Lung Diseases / Q000150:complications / Q000175:diagnosis; D008175:Lung Neoplasms / Q000150:complications / Q000175:diagnosis; D008223:Lymphoma / Q000150:complications / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009369:Neoplasms / Q000150:complications* / Q000175:diagnosis; D012189:Retrospective Studies; D014397:Tuberculosis, Pulmonary / Q000150:complications* / Q000175:diagnosis; D014625:Vaginal Neoplasms / Q000150:complications / Q000175:diagnosis
keywords: Idiopathic; SIADH; Workup