2019 Volume 65 Issue 5 Pages 371-375
Localized herpes zoster is a disease with vesicular lesion formation in a circumscribed area of the body, caused by reactivation of varicella-zoster virus. The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is one of the causes of hyponatremia, an electrolyte abnormality that occurs when blood sodium level drops to less than 135 mEq/L, but reportedly, localized herpes zoster is rarely accompanied by SIADH.
An 87-year-old woman with a diagnosis of herpes zoster of the third division of the left trigeminal nerve received intravenous acyclovir on an inpatient basis in our department. Despite an improvement in symptoms, the blood sodium level decreased to 114 mEq/L after intravenous infusions of acyclovir for 6 days. Test results confirmed a diagnosis of SIADH, and treatment with physiological saline and the restriction of fluid intake helped improve the blood sodium level.
Our search for localized herpes zoster accompanied by SIADH resulted in 14 cases including the above one (average number of days until onset: 7.38 days, average blood sodium level at onset: 114.1 mEq/L). Treatment with physiological saline and the restriction of fluid intake were effective in all cases. It is important to confirm complications of SIADH by regularly testing blood sodium levels when localized herpes zoster is treated.
