Background: Gatifloxacin is a widely used fluoroquinolone antibiotic. Several case reports have described hyperglycemia that is related to gatifloxacin use.
Objective: Our goal was to report a new case of gatifloxacin-related hyperglycemia in a nondiabetic patient with acute renal dysfunction. Also summarized are data from existing case reports.
Case summary: A 71-year-old man with a history of coronary artery disease was admitted for saphenous vein harvest site infection, atrial fibrillation, postoperative Dressler's syndrome, and resolving acute renal failure after coronary artery bypass graft 10 days prior. His history was notable for the absence of diabetes mellitus. Four days after initiating gatifloxacin 400 mg/d for a wound infection and 3 days after an increase in serum creatinine to 2.8 mg/dL, his fasting serum glucose level was elevated to 209 mg/dL on routine laboratory evaluation. Standard dose sliding scale insulin was begun to control the patient's blood glucose, and his gatifloxacin dose was lowered to 200 mg/d due to his diminished renal function. The patient's blood glucose levels normalized rapidly after his course of gatifloxacin was completed.
Discussion: Thirteen cases of gatifloxacin-related hyperglycemia have been reported in the medical literature, 10 of which were in nondiabetic patients and at least 9 of which were in patients with creatinine clearance levels <50 mL/min. Although the mechanism for the adverse effect is poorly understood, it appears to be dose dependent and more likely to occur in patients with renal insufficiency.
Conclusion: In this patient with impaired renal function, gatifloxacin was probably associated with hyperglycemia.