# Syndrome of inappropriate antidiuretic hormone secretion following extensively drug-resistant Klebsiella pneumoniae associated with complicated urinary tract infection: a case report

## TL;DR

An elderly man with severe, treatment-resistant low sodium levels was found to have a rare, drug-resistant urinary tract infection linked to a hormone disorder.

## Contribution

This case report highlights a previously unrecognized link between XDRKP infection and SIADH.

## Key findings

- Refractory hyponatremia resolved after treating XDRKP infection with tigecycline.
- XDRKP may be a cause of SIADH in patients unresponsive to standard treatments.
- Antimicrobial therapy is crucial for managing electrolyte disorders from drug-resistant UTIs.

## Abstract

Hyponatremia is strongly associated with syndrome of inappropriate antidiuretic hormone secretion (SIADH). We present an 82-year-old male with refractory hyponatremia unresponsive to the discontinuation of hydrochlorothiazide and comprehensive treatment (fluid restriction, sodium supplementation, and tolvaptan). Two consecutive urine cultures identified extensively drug-resistant Klebsiella pneumoniae (XDRKP). After tigecycline treatment, serum sodium returned to normal and remained stable during one-year follow-up. This case suggests a close relationship between XDRKP infection and SIADH, highlighting the need to evaluate drug-resistant pathogens in patients with refractory hyponatremia and the importance of antimicrobial therapy in the management of electrolyte disorders secondary to drug-resistant urinary tract infections.