Recurrence of SIADH With Localized Herpes Zoster InfectionCerejo, Russell MD*; Kovacs, Christopher Jr MD†; Hatipoglu, Betul MD‡Infectious Diseases in Clinical Practice: March 2013 - Volume 21 - Issue 2 - p 139–140 doi: 10.1097/IPC.0b013e3182699166 Case Reports Abstract In Brief Author Information Abstract: Localized herpes zoster (HZ) is rarely associated with a concomitant syndrome of inappropriate antidiuretic hormone secretion (SIADH). We present the case of 59-year-old woman being treated for chronic lymphocytic leukemia who had 2 separate episodes of localized HZ complicated by simultaneous SIADH. No other identifiable cause of SIADH was identified. Hyponatremia improved with antiviral therapy, and resolution paralleled improvement in skin lesions in both instances. This represents a unique situation of documented recurrence of SIADH with relapsed HZ. Clinicians should consider the possibility of concomitant SIADH in a patient with localized HZ even in the absence of symptoms. We suggest that the severity of HZ manifestations and the degree of hyponatremia may be positively correlated. Further investigation into the pathophysiologic mechanism for this association is warranted. Cerejo et al. present a 59-year-old female who presented with two separate episodes of localized Herpes Zoster and concomitant SIADH. There were no other identifiable caused of SIADH in this patient during both presentations. This represents a unique situation of documented recurrence of SIADH with relapsed HZ. Clinicians should consider the possibility of concomitant SIADH in a patient with localized HZ, even in the absence of symptoms. From the Departments of *Neurology, †Internal Medicine, and ‡Endocrinology, Diabetes and Metabolism, Cleveland Clinic Foundation, Cleveland, OH. Correspondence to: Russell Cerejo, MD, Department of Neurology, S100c, Cleveland Clinic Foundation, Cleveland, OH 44195. E-mail: firstname.lastname@example.org. The authors have no funding or conflicts of interest to disclose. © 2013 by Lippincott Williams & Wilkins.