RESUMO
BACKGROUND: Vancomycin is used on a large scale in medical practice, mostly for the treatment of serious gram-positive bacterial infection. Many adverse effects have been linked to vancomycin use with nephrotoxicity being one of its most prevalent side effects. CASE REPORT: We present the case of an 81 years-old woman who had sustained vancomycin-induced hypokalemia while treating an infected surgical wound. She was under chronic use of losartan for high blood pressure but she was not diabetic. Potassium in serum reached critically low levels during the use of this antibiotic - despite intravenous reposition - and returned to normal right after the drug was stopped, in two different occasions. Elevated urinary potassium levels indicated renal potassium wasting, though serum creatinine levels remained within the normal range throughout hospitalization. CONCLUSIONS: Vancomycin must be considered as a possible cause for hypokalemia of unknown etiology and physicians should be aware of this potential severe adverse effect.
