A rare case of combined syndrome of inappropriate antidiuretic hormone secretion and Fanconi syndrome in an elderly woman.
An 83-year-old Japanese woman was admitted to our hospital with severe hyponatremia (sodium, 108 mEq/L [108 mmol/L]), hypokalemia, hypochloridemia, hypocalcemia, hypophosphatemia, and hypouricemia. Despite low plasma osmolarity (232 mOsm/kg [232 mmol/kg]), urine osmolarity (320 mOsm/kg) was greater than that of plasma, and she had increased urinary sodium excretion (88 mEq/L [88 mmol/L]) and an unsuppressed high plasma level of antidiuretic hormone (ADH; 5.5 pg/mL [5.1 pmol/L]). These findings indicated that she had syndrome of inappropriate ADH secretion (SIADH). In addition, she had a generalized reabsorption defect of the proximal tubules, including decreased tubular reabsorption of phosphate, increased fractional excretion of uric acid, glycosuria despite a normal blood glucose level, and panaminoaciduria. Thus, combined SIADH and Fanconi syndrome was diagnosed. The cause was thought to be the antidepressant paroxetine, which is a selective serotonin reuptake inhibitor (SSRI). Several of the abnormal values resolved within 1 week after discontinuation of this drug. Although the precise mechanism responsible was not elucidated, we report an extremely rare case of combined SIADH and Fanconi syndrome, probably caused by short-term SSRI therapy.
Ishii
Tomoko
T
Department of Nephrology and the Kidney and Dialysis Center, Shonan Kamakura General Hospital, Yamazaki, Kamakura, Japan.
Ohtake
Takayasu
T
Yasu
Takeo
T
Kadotani
Yasuhiro
Y
Hayashi
Shuji
S
Oka
Machiko
M
Maesato
Kyoko
K
Mano
Tsutomu
T
Ikee
Ryota
R
Moriya
Hidekazu
H
Kobayashi
Shuzo
S
D000368:Aged; D000369:Aged, 80 and over; D005198:Fanconi Syndrome / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000209:etiology* / Q000473:pathology; D017374:Paroxetine / Q000009:adverse effects* / Q000627:therapeutic use; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use
D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors